1. A process for improving the quality of a desulfurization solution and obtaining high-quality sulfur, comprising the steps of:

a, filtration: heating the desulfurization waste liquid, or heating sulfur paste and molten sulfur, or heating molten sulfur to convert solid sulfur into liquid sulfur, filtering the heated solution to remove solid ash, and respectively obtaining high-quality sulfur, desulfurization solution without ash and oil, oil and ash after supergravity separation, liquid-sulfur separation and oil-liquid separation of the filtrate;

b, deslagging: at the final stage of filtration, washing the filter with partial hot oily solution, feeding residual liquid sulfur in the filter into a slag discharge tank along with the solution, and feeding discharged materials in the slag discharge tank back to the filter for filtration and separation;

c assisting in the establishment of the filter cake: after the filter is subjected to slag discharge, qualified auxiliary filter cakes are established on filter screens of all filter plates of the filter by adopting auxiliary filter liquor so as to meet the requirement of separation degree of ash residues in the desulfurization waste liquid.

2. The process for improving the quality of desulfurization solution and obtaining high-quality sulfur according to claim 1, wherein said desulfurization waste liquid is derived from a wet oxidation desulfurization system effluent of a hydrogen sulfide-containing gas or a hydrogen sulfide-containing tail gas, and said desulfurization waste liquid contains one or more of solid foam sulfur, salts, ash and oils; the sulfur paste is a filter cake obtained by filtering the desulfurization waste liquid through a plate frame or centrifugal filtration, and the molten sulfur is obtained by melting the desulfurization waste liquid through a sulfur melting kettle.

3. The process for improving the quality of a desulfurization solution and obtaining high-quality sulfur according to claim 1, wherein the step a filtration employs any one of the following;

filtering A1, allowing the desulfurization waste liquid to enter a desulfurization waste liquid heat exchanger to exchange heat with the hot oil-containing solution before entering an oil-liquid separator, and allowing the desulfurization waste liquid after heat exchange to enter a desulfurization waste liquid heater to be heated by steam; the heated desulfurization waste liquid enters a filter for filtering, the filter liquid without ash and slag enters a hypergravity separator for separation, and most of hot oil-containing solution leaves from the top of the hypergravity separator and enters a desulfurization waste liquid heat exchanger; discharging all liquid sulfur and residual oil-containing solution from the bottom of the supergravity separator, feeding the liquid sulfur into a liquid sulfur separator, and obtaining high-quality liquid sulfur at the bottom of the liquid sulfur separator, wherein the purity of the high-quality liquid sulfur is more than or equal to 99.95 wt%, and feeding part of the liquid sulfur into a filter aid tank; the hot oil-containing solution leaving the top of the liquid-sulfur separator also enters a desulfurization waste liquid heat exchanger, part of the cold oil-containing solution after heat exchange with the desulfurization waste liquid in the desulfurization waste liquid heat exchanger is sent into the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest part of the cold oil-containing solution enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to a separated oil recovery device outside a battery compartment; or a desulfurization waste liquid heat exchanger is canceled, namely, part of the hot oil-containing solution directly enters the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest hot oil-containing solution is cooled and then enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to a separated oil recovery device outside the battery limit;

filtering A2, allowing the desulfurization waste liquid to enter a desulfurization waste liquid heat exchanger to exchange heat with the hot oil-containing solution before entering an oil-liquid separator, and allowing the desulfurization waste liquid after heat exchange to enter a desulfurization waste liquid heater to be heated by steam; the heated desulfurization waste liquid enters a filter to be filtered, the filter liquid without ash residues directly enters a liquid sulfur separator, and high-quality liquid sulfur is obtained at the bottom of the liquid sulfur separator, wherein the purity of the high-quality liquid sulfur is more than or equal to 99.95 wt%; the hot oily solution leaving the top of the liquid-sulfur separator enters a desulfurization waste liquid heat exchanger, part of the cold oily solution after heat exchange with the desulfurization waste liquid in the desulfurization waste liquid heat exchanger is sent into the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest part of the cold oily solution enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to a separated oil recovery device outside a battery compartment; sending part of the oil-containing solution in front of the desulfurization waste liquid heat exchanger into a filter aid tank; or a desulfurization waste liquid heat exchanger is canceled, namely, part of the hot oil-containing solution directly enters the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest hot oil-containing solution is cooled and then enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to a separated oil recovery device outside the battery limit; sending part of the hot oil-containing solution into a filter aid tank;

filtering A3, allowing the desulfurization waste liquid to enter a desulfurization waste liquid heat exchanger to exchange heat with the hot oil-containing solution before entering an oil-liquid separator, and allowing the desulfurization waste liquid after heat exchange to enter a desulfurization waste liquid heater to be heated by steam; the heated desulfurization waste liquid directly enters a pre-separator, hot oil-containing solution at the top of the pre-separator enters a desulfurization waste liquid heat exchanger, ash-containing solution in the middle of the pre-separator and liquid sulfur discharged from the bottom of the pre-separator are mixed together and sent into a filter for filtering, filter liquor without ash enters a super-gravity separator for separation, and most of the hot oil-containing solution leaves from the top of the super-gravity separator and enters the desulfurization waste liquid heat exchanger; discharging all liquid sulfur and residual oil-containing solution from the bottom of the supergravity separator, feeding the discharged liquid sulfur and residual oil-containing solution into a liquid sulfur separator, and obtaining high-quality liquid sulfur at the bottom of the liquid sulfur separator, wherein the purity is more than or equal to 99.95 wt%; the hot oil-containing solution leaving the top of the liquid-sulfur separator also enters a desulfurization waste liquid heat exchanger, part of the cold oil-containing solution after heat exchange with the desulfurization waste liquid in the desulfurization waste liquid heat exchanger is sent into the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest part of the cold oil-containing solution enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to an oil separation and recovery device outside the battery compartment; sending part of hot oil-containing solution before heat exchange of the desulfurization waste liquid into a filter aid tank; or a desulfurization waste liquid heat exchanger is canceled, namely, part of the hot oil-containing solution directly enters the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest hot oil-containing solution is cooled and then enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to a separated oil recovery device outside the battery limit; sending part of the hot oil-containing solution into a filter aid tank;

filtering A4, allowing the desulfurization waste liquid to enter a desulfurization waste liquid heat exchanger to exchange heat with the hot oil-containing solution before entering an oil-liquid separator, and allowing the desulfurization waste liquid after heat exchange to enter a desulfurization waste liquid heater to be heated by steam; the heated desulfurization waste liquid directly enters a pre-separator, hot oil-containing solution at the top of the pre-separator enters a desulfurization waste liquid heat exchanger, ash-containing solution in the middle of the pre-separator and liquid sulfur discharged from the bottom of the pre-separator can be sent into a filter together for filtering or respectively sent into different filters for filtering, filter liquor with ash removed is mixed and enters a liquid sulfur separator for separation, high-quality liquid sulfur is obtained at the bottom of the liquid sulfur separator, the purity is more than or equal to 99.95 wt%, and part of the liquid sulfur is sent into a filter aid tank; the hot oily solution leaving the top of the liquid-sulfur separator enters a desulfurization waste liquid heat exchanger, part of the cold oily solution after heat exchange with the desulfurization waste liquid in the desulfurization waste liquid heat exchanger is sent into the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest part of the cold oily solution enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to an oil separation and recovery device outside a battery compartment; or a desulfurization waste liquid heat exchanger is canceled, namely, part of the hot oil-containing solution directly enters the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest hot oil-containing solution is cooled and then enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to a separated oil recovery device outside the battery limit; or the liquid sulfur discharged from the bottom of the pre-separator is filtered in a filter to directly obtain filtrate, namely high-quality liquid sulfur, the purity of the high-quality liquid sulfur is more than or equal to 99.95 wt%, and the filtrate can not enter the liquid sulfur separator;

filtering A5, wherein molten sulfur enters from a hopper chute at the top of a pre-separator and is indirectly heated and molten, a solution containing ash and slag at the middle upper part of the pre-separator and liquid sulfur discharged from the bottom of the pre-separator are mixed and sent into a filter together for filtering or respectively sent into different filters for filtering, the filtrate is high-quality liquid sulfur, the purity is more than or equal to 99.95 wt%, and part of the liquid sulfur is sent into a filter aid tank; before part of the liquid sulfur is sent into the filter, the liquid sulfur is mixed with the ash-containing solution to be filtered and the liquid sulfur discharged from the bottom of the pre-separator;

filtering A6, sulfur paste, or sulfur paste and molten sulfur enter from a hopper chute at the top of a pre-separator and are indirectly heated and melted, hot oil-containing solution on the side surface of the upper part of the pre-separator enters a cooler, ash-containing solution in the middle of the pre-separator and liquid sulfur discharged from the bottom of the pre-separator are respectively sent to different filters for filtering, filtrate from which ash is removed is mixed and enters a liquid sulfur separator for separation, high-quality liquid sulfur is obtained at the bottom of the liquid sulfur separator, and the purity of the high-quality liquid sulfur is more than or equal to 99.95 wt%; the hot oily solution leaving the top of the liquid-sulfur separator also enters a cooler, the oily solution cooled in the cooler by cooling water enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to an oil separation and recovery device outside a battery compartment; the hot oil-containing solution part in front of the cooler is sent to the front of the filter; the hot oil-containing solution part in front of the cooler is sent into a filtrate assisting tank; or the liquid sulfur discharged from the bottom of the pre-separator is sent into a filter for filtering, and the directly obtained filtrate is the high-quality liquid sulfur, the purity is more than or equal to 99.95 wt%, and the filtrate can not enter the liquid sulfur separator.

4. The process for improving the quality of desulfurization solution and obtaining high-quality sulfur according to claim 1, wherein said step B of discharging slag comprises the steps of: before opening a slag discharge valve or a machine shell of the filter to discharge slag, residual liquid in the filter needs to be discharged into a discharge groove, and the filter is flushed by partial hot oil-containing solution in front of a desulfurization waste liquid heat exchanger or partial hot oil-containing solution in front of a cooler, so that the sulfur content in ash slag is less than 0.1 wt%; after qualified auxiliary filter cakes are established on the filter screens of all the filter plates in the filter, all the discharged materials in the discharge groove are sent back to the filter by the discharge pump for filtering.

5. The process for improving the quality of desulfurization solution and obtaining high-quality sulfur according to claim 1, wherein said step C for assisting in the establishment of filter cake comprises the steps of: respectively sending liquid sulfur and a filter aid into a filtrate-assisting tank, sending the filtrate in the filtrate-assisting tank into a filter by a filtrate-assisting pump, and establishing qualified auxiliary filter cakes on filter screens of all filter plates in the filter; hot oily solutions may also be used in place of liquid sulphur.

6. A system for improving the quality of a desulfurization solution and obtaining high-quality sulfur is characterized by comprising a filter unit, a supergravity separator and a preseparator; a filtrate outlet of a filter of the filter unit is connected with a filtrate inlet of the supergravity separator; the ash-containing solution outlet and the bottom liquid sulfur outlet of the pre-separator are mixed together and connected with the inlets of the filters or respectively connected with the inlets of different filters.

7. The system for improving the quality of the desulfurization solution and obtaining high-quality sulfur according to claim 6, wherein the filter unit comprises a filter, a filtrate-assisting tank, a filtrate-assisting pump, a discharge tank and a discharge pump, an overflow outlet of the filter is connected with an overflow inlet of the filtrate-assisting tank, a filtrate outlet of the filter is connected with an overflow inlet of the filtrate-assisting tank, and a filtrate-assisting outlet of the filtrate-assisting tank is connected with a filtrate inlet to be filtered of the filter through the filtrate-assisting pump; a discharge outlet of the discharge groove is connected with a liquid inlet to be filtered of the filter through a discharge pump; the discharge outlet of the filter is connected with the discharge inlet of the discharge groove.

8. The system for improving the quality of desulfurization solution and obtaining high-quality sulfur according to claim 7, wherein said filter is a vertical filter or a horizontal filter; the vertical filter is of a vertical cylindrical structure and a lower conical structure, the upper shell is provided with a connecting flange, and the bottom of the vertical filter is provided with a slag discharge valve; the horizontal filter is of a horizontal cylindrical structure, a hydraulic fastening flange is arranged on the front shell, and the shell at the rear part of the flange is pushed backwards horizontally by hydraulic pressure to discharge slag; the shell of the filter is insulated by a steam jacket;

a plurality of filter plates are arranged in the filter in parallel, the filter plates are circular or rectangular, the filter plates are of hollow structures, filter screens are arranged on two sides of each filter plate, metal frames are arranged on the periphery of each filter plate, the filter screens are hermetically connected with the metal frames on the periphery of each filter plate, a filtrate outlet interface is arranged at the bottom of each filter plate, and the filtrate outlet interface of each filter plate is hermetically connected with a filtrate collecting outlet pipe; the auxiliary filter cake completely covers the surfaces of the filter screens at the two sides of each filter plate;

when the ash content in the desulfurization waste liquid is low, a horizontal bed filter can be adopted to filter the heated desulfurization waste liquid.

9. The system for improving the quality of the desulfurization solution and obtaining high-quality sulfur according to claim 6, wherein the hypergravity separator is of a vertical cylindrical structure, and a plurality of micro cyclone separation tubes are arranged inside the hypergravity separator; the lateral surface of the hypergravity separator is provided with a filtrate inlet, the top and the bottom of the hypergravity separator are respectively provided with an outlet, and the hypergravity separator is divided into three closed cavities from top to bottom by the three interfaces, namely an overflow cavity positioned at a top outlet area, a feeding cavity positioned at a middle feeding area and a bottom flow cavity positioned at a bottom outlet area.

10. The system for improving the quality of desulfurization solution and obtaining high-quality sulfur according to claim 6, wherein said preseparator has a vertical cylindrical structure and can be fed with one or more of the following three materials:

the preseparator is suitable for feeding and is desulfurization waste liquid: the side surface of the pre-separator is provided with a desulfurization waste liquid inlet and an ash-containing solution outlet, the top of the pre-separator is provided with a hot oil-containing solution outlet, the bottom of the pre-separator is provided with a liquid sulfur outlet, the pre-separator is divided into three areas from top to bottom according to different densities, the top of the pre-separator is an oil-containing solution outlet area, the middle of the pre-separator is a desulfurization waste liquid feeding area and an ash-containing solution pumping area, and the bottom of the pre-separator is a liquid sulfur outlet area; the diameter of the liquid sulfur area is about 30-100% of the diameter of the upper area; the desulfurization waste liquid inlet and the area below the desulfurization waste liquid inlet are insulated by a steam jacket, and the steam jacket is provided with a steam inlet and a condensate outlet; the ash-containing liquid outlet is a horizontal pipe outlet pipeline or a pipe section which is horizontal and then vertical;

or, a preseparator suitable for feeding sulfur paste and molten sulfur: the side surface of the pre-separator is provided with a hot oil-containing solution outlet and an ash-containing solution outlet, the top of the pre-separator is provided with a feed inlet, the bottom of the pre-separator is provided with a liquid sulfur outlet, the pre-separator is divided into four areas from top to bottom by the four interfaces, the top of the pre-separator is a feed area, the upper part of the side surface is an oil-containing solution outlet area, the middle part of the pre-separator is an ash-containing solution extraction area; the diameter of the liquid sulfur area is about 30-100% of the diameter of the upper area; the feed inlet and the area below the feed inlet are insulated by a steam jacket, and a steam inlet and a condensate outlet are arranged on the steam jacket; the ash-containing liquid outlet is a horizontal pipe outlet pipeline or a pipe section which is horizontal and then vertical.

Or, a preseparator suitable for feeding molten sulfur: the side surface of the pre-separator is provided with an ash-containing solution outlet, the top of the pre-separator is provided with a feed inlet, the bottom of the pre-separator is provided with a liquid sulfur outlet, the pre-separator is divided into three areas from top to bottom by the three interfaces, the top of the pre-separator is a feed area, the middle upper part of the pre-separator is an ash-containing solution extraction area, and the bottom of the pre-separator is a liquid sulfur outlet area; the diameter of the liquid sulfur area is about 30-100% of the diameter of the upper area; the feed inlet and the area below the feed inlet are insulated by a steam jacket, and a steam inlet and a condensate outlet are arranged on the steam jacket; the ash-containing liquid outlet is a horizontal pipe outlet pipeline or a pipe section which is horizontal and then vertical.

Background

At present, two modes of filtration (plate frame or centrifugation) or sulfur melting in a sulfur melting kettle are mostly adopted for treating the desulfurization waste liquid of wet oxidation desulfurization in China.

The desulfurization waste liquid contains one or more of solid foam sulfur, salts, ash residues and oil, the solid foam sulfur adsorbs the ash residues and the oil, the sulfur paste obtained by filtering or called sulfur paste and the molten sulfur obtained by melting sulfur in a sulfur melting kettle have poor quality and low purity and are difficult to sell.

Disclosure of Invention

The invention aims to provide a process for improving the quality of a desulfurization solution and obtaining high-quality sulfur aiming at various problems in the treatment of the desulfurization waste liquid by a wet oxidation method, the process can obtain high-quality liquid sulfur (hereinafter referred to as liquid sulfur) from the desulfurization waste liquid containing solid foam sulfur, salts, ash and oil, or sulfur paste and molten sulfur, or molten sulfur, the purity of the high-quality liquid sulfur is more than or equal to 99.95 wt%, ash and oil in the desulfurization solution are removed, the quality of the desulfurization solution of a desulfurization system is improved, and the sulfur content in the ash and slag is less than 0.1 wt%.

In order to achieve the purpose, the invention adopts the technical scheme that: a process for improving the quality of a desulfurization solution and obtaining high-quality sulfur comprises the following steps:

a, filtration: heating the desulfurization waste liquid, or heating sulfur paste and molten sulfur, or heating molten sulfur to convert solid sulfur into liquid sulfur, filtering the heated solution to remove solid ash, and respectively obtaining high-quality sulfur, desulfurization solution without ash and oil, oil and ash after supergravity separation, liquid-sulfur separation and oil-liquid separation of the filtrate; the supergravity separation can be selected according to the material state; in the case of molten sulfur as the raw material, liquid sulfur separation and oil-liquid separation are not required.

B, deslagging: in the final stage of filtration, the final stage of filtration means that the filter stops filtering and feeding materials, before slag is discharged, the filter is flushed by partial hot oil-containing solution, residual liquid sulfur in the filter enters a slag discharge groove along with the solution, and discharged materials in the slag discharge groove are returned to the filter for filtering and separation, so that the sulfur content in slag discharge ash is reduced, and the sulfur yield is improved;

c assisting in the establishment of the filter cake: after the filter is subjected to slag discharge, qualified auxiliary filter cakes are established on filter screens of all filter plates of the filter by adopting auxiliary filter liquor so as to meet the requirement of separation degree of ash residues in the desulfurization waste liquid; the qualified auxiliary filter cake is established by filtering the filter aid liquid entering the filter by the filter, wherein the ash content in the filter liquid is less than 0.05 wt%.

Further, the desulfurization waste liquid is discharged from a wet oxidation desulfurization system of hydrogen sulfide-containing gas or hydrogen sulfide-containing tail gas, the desulfurization waste liquid contains one or more of solid foam sulfur, salts, ash and oils, and the desulfurization waste liquid contains the following components: 0.1-15 wt% of sulfur (solid suspended sulfur), 0.01-3 wt% of ash, 0.1-30 g/L of oil, soluble salts and water; the ash and oil in the desulfurization waste liquid come from a desulfurization system. The sulfur paste or the sulfur paste is a filter cake obtained by plate-frame filtration or centrifugal filtration of the desulfurization waste liquid, and the water content of the filter cake is 20-60%; the molten sulfur is obtained by melting the desulfurization waste liquid in a sulfur melting kettle indirectly heated by steam, and the molten sulfur is solid.

Further, the step A filtration adopts any one of the following;

filtering A1, allowing the desulfurization waste liquid to enter a desulfurization waste liquid heat exchanger to exchange heat with the hot oil-containing solution before entering an oil-liquid separator, and allowing the desulfurization waste liquid after heat exchange to enter a desulfurization waste liquid heater to be heated by steam; the heated desulfurization waste liquid enters a filter for filtering, the filter liquid without ash and slag enters a hypergravity separator for separation, and most of hot oil-containing solution leaves from the top of the hypergravity separator and enters a desulfurization waste liquid heat exchanger; discharging all liquid sulfur and residual oil-containing solution from the bottom of the supergravity separator, feeding the liquid sulfur into a liquid sulfur separator, and obtaining high-quality liquid sulfur at the bottom of the liquid sulfur separator, wherein the purity of the high-quality liquid sulfur is more than or equal to 99.95 wt%, and feeding part of the liquid sulfur into a filter aid tank; the hot oil-containing solution leaving the top of the liquid-sulfur separator also enters a desulfurization waste liquid heat exchanger, part of the cold oil-containing solution after heat exchange with the desulfurization waste liquid in the desulfurization waste liquid heat exchanger is sent into the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest part of the cold oil-containing solution enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system so as to supplement the lost liquid of the desulfurization system and reduce the consumption of a desulfurization catalyst, and the separated oil is sent to a separated oil recovery device outside a battery compartment; or a desulfurization waste liquid heat exchanger is canceled, namely, part of the hot oil-containing solution directly enters the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest hot oil-containing solution is cooled and then enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to a separated oil recovery device outside the battery limit;

filtering A2, allowing the desulfurization waste liquid to enter a desulfurization waste liquid heat exchanger to exchange heat with the hot oil-containing solution before entering an oil-liquid separator, and allowing the desulfurization waste liquid after heat exchange to enter a desulfurization waste liquid heater to be heated by steam; the heated desulfurization waste liquid enters a filter to be filtered, the filter liquid without ash residues directly enters a liquid sulfur separator, and high-quality liquid sulfur is obtained at the bottom of the liquid sulfur separator, wherein the purity of the high-quality liquid sulfur is more than or equal to 99.95 wt%; the hot oily solution leaving the top of the liquid-sulfur separator enters a desulfurization waste liquid heat exchanger, part of the cold oily solution after heat exchange with the desulfurization waste liquid in the desulfurization waste liquid heat exchanger is sent into the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest part of the cold oily solution enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system so as to supplement the lost liquid of the desulfurization system and reduce the consumption of a desulfurization catalyst, and the separated oil is sent to a separated oil recovery device outside a battery limit; sending part of the oil-containing solution in front of the desulfurization waste liquid heat exchanger into a filter aid tank; or a desulfurization waste liquid heat exchanger is canceled, namely, part of the hot oil-containing solution directly enters the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest hot oil-containing solution is cooled and then enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to a separated oil recovery device outside the battery limit; sending part of the hot oil-containing solution into a filter aid tank;

filtering A3, allowing the desulfurization waste liquid to enter a desulfurization waste liquid heat exchanger to exchange heat with the hot oil-containing solution before entering an oil-liquid separator, and allowing the desulfurization waste liquid after heat exchange to enter a desulfurization waste liquid heater to be heated by steam; the heated desulfurization waste liquid directly enters a pre-separator, hot oil-containing solution at the top of the pre-separator enters a desulfurization waste liquid heat exchanger, ash-containing solution (also containing partial liquid sulfur, the same below) in the middle of the pre-separator and liquid sulfur discharged from the bottom of the pre-separator are mixed together and sent into a filter for filtering, filtrate with ash removed enters a super-gravity separator for separation, and most of the hot oil-containing solution leaves from the top of the super-gravity separator and enters the desulfurization waste liquid heat exchanger; discharging all liquid sulfur and residual oil-containing solution from the bottom of the supergravity separator, feeding the discharged liquid sulfur and residual oil-containing solution into a liquid sulfur separator, and obtaining high-quality liquid sulfur at the bottom of the liquid sulfur separator, wherein the purity is more than or equal to 99.95 wt%; the hot oil-containing solution leaving the top of the liquid-sulfur separator also enters a desulfurization waste liquid heat exchanger, part of the cold oil-containing solution after heat exchange with the desulfurization waste liquid in the desulfurization waste liquid heat exchanger is sent into the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest part of the cold oil-containing solution enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system so as to supplement the lost liquid of the desulfurization system and reduce the consumption of a desulfurization catalyst, and the separated oil is sent to a separation oil recovery device outside the battery limits; sending part of hot oil-containing solution before heat exchange of the desulfurization waste liquid into a filter aid tank; or a desulfurization waste liquid heat exchanger is canceled, namely, part of the hot oil-containing solution directly enters the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest hot oil-containing solution is cooled and then enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to a separated oil recovery device outside the battery limit; sending part of the hot oil-containing solution into a filter aid tank;

filtering A4, allowing the desulfurization waste liquid to enter a desulfurization waste liquid heat exchanger to exchange heat with the hot oil-containing solution before entering an oil-liquid separator, and allowing the desulfurization waste liquid after heat exchange to enter a desulfurization waste liquid heater to be heated by steam; the heated desulfurization waste liquid directly enters a pre-separator, hot oil-containing solution at the top of the pre-separator enters a desulfurization waste liquid heat exchanger, ash-containing solution in the middle of the pre-separator and liquid sulfur discharged from the bottom of the pre-separator can be sent into a filter together for filtering or respectively sent into different filters for filtering, filter liquor with ash removed is mixed and enters a liquid sulfur separator for separation, high-quality liquid sulfur is obtained at the bottom of the liquid sulfur separator, the purity is more than or equal to 99.95 wt%, and part of the liquid sulfur is sent into a filter aid tank; the hot oil-containing solution leaving the top of the liquid-sulfur separator enters a desulfurization waste liquid heat exchanger, part of the cold oil-containing solution after heat exchange with the desulfurization waste liquid in the desulfurization waste liquid heat exchanger is sent into the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest part of the cold oil-containing solution enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system so as to supplement the lost liquid of the desulfurization system and reduce the consumption of a desulfurization catalyst, and the separated oil is sent to an oil separation recovery device outside a battery compartment; or a desulfurization waste liquid heat exchanger is canceled, namely, part of the hot oil-containing solution directly enters the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, the rest hot oil-containing solution is cooled and then enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to a separated oil recovery device outside the battery limit; or the liquid sulfur discharged from the bottom of the pre-separator is filtered in a filter to directly obtain filtrate, namely high-quality liquid sulfur, the purity of the high-quality liquid sulfur is more than or equal to 99.95 wt%, and the filtrate can not enter the liquid sulfur separator;

filtering A5, wherein molten sulfur enters from a hopper chute at the top of a pre-separator and is indirectly heated and molten, a solution containing ash and slag at the middle upper part of the pre-separator (the solution is liquid sulfur, the same applies below) and liquid sulfur discharged from the bottom of the pre-separator are mixed together and sent into a filter to be filtered or respectively sent into different filters to be filtered, the filtrate is high-quality liquid sulfur, the purity of the high-quality liquid sulfur is more than or equal to 99.95 wt%, and part of the liquid sulfur is sent into a filter aid tank; before part of the liquid sulfur is sent into the filter, the liquid sulfur is mixed with the ash-containing solution to be filtered and the liquid sulfur discharged from the bottom of the pre-separator;

filtering A6, sulfur paste, or sulfur paste and molten sulfur enter from a hopper chute at the top of a pre-separator and are indirectly heated and melted, hot oil-containing solution on the side surface of the upper part of the pre-separator enters a cooler, ash-containing solution (also containing partial liquid sulfur, the same applies below) in the middle of the pre-separator and liquid sulfur discharged from the bottom of the pre-separator are respectively sent to different filters for filtering, filtrate for removing ash is mixed together and enters a liquid sulfur separator for separation, high-quality liquid sulfur is obtained at the bottom of the liquid sulfur separator, and the purity of the high-quality liquid sulfur is more than or equal to 99.95 wt%; the hot oil-containing solution leaving the top of the liquid-sulfur separator also enters a cooler, the oil-containing solution cooled in the cooler by cooling water enters an oil-liquid separator, the separated desulfurization solution without ash and oil returns to a desulfurization system to supplement the lost liquid of the desulfurization system and reduce the consumption of a desulfurization catalyst, and the separated oil is sent to an oil separation recovery device outside the battery limits; the hot oil-containing solution part in front of the cooler is sent to the front of the filter; the hot oil-containing solution part in front of the cooler is sent into a filtrate assisting tank; or the liquid sulfur discharged from the bottom of the pre-separator is sent into a filter for filtering, and the directly obtained filtrate is the high-quality liquid sulfur, the purity is more than or equal to 99.95 wt%, and the filtrate can not enter the liquid sulfur separator.

Further, the step B comprises the following steps: before opening a slag discharge valve or a shell of the filter to discharge slag, residual liquid in the filter needs to be discharged into a discharge groove, and a part of hot oil-containing solution in front of a desulfurization waste liquid heat exchanger or a part of hot oil-containing solution in front of a cooler is adopted to flush the filter, so that the sulfur content in ash slag is less than 0.1 wt%, and the flushing liquid is discharged into the discharge groove; after qualified auxiliary filter cakes are established on the filter screens of all the filter plates in the filter, all the discharged materials in the discharge tank are sent back to the filter by the discharge pump for filtering; the hot oil-containing solution is adopted to flush the filter, thereby quickening the discharge of the liquid sulfur into the discharge tank and shortening the deslagging period of the filter.

Further, the step C assists in the establishment of the filter cake comprising the steps of: respectively sending liquid sulfur and a filter aid into a filtrate-assisting tank, sending the filtrate in the filtrate-assisting tank into a filter by a filtrate-assisting pump, and establishing qualified auxiliary filter cakes on filter screens of all filter plates in the filter; hot oily solutions may also be used in place of liquid sulphur.

Further, the temperature of the desulfurization waste liquid after the heater is 119-159 ℃. The preferred temperature is 130-140 ℃; the filter unit, supergravity separator, liquid-sulfur separator, oil-liquid separator, preseparator and pipeline are also operated at this temperature.

Furthermore, the part of the oil-containing solution directly enters the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, or the part of the hot oil-containing solution directly enters the desulfurization waste liquid before the desulfurization waste liquid heater, or the part of the filtered liquid sulfur enters the liquid to be filtered before the filter, so that the operation of the filter is stable and reliable and the filtering period of a single filter is prolonged; the stable and reliable operation index of the filter is that the flow of the liquid to be filtered of each square meter of the filter screen is 0.1-1.5 m³Per h, the preferred operating index is to have a filter screen per square meterThe flow rate of the filtrate is 0.5-1.0 m³/h。

The invention also discloses a system for improving the quality of the desulfurization solution and obtaining high-quality sulfur, which has a reasonable structure, is effective and reliable, separates sulfur, ash and oil from the desulfurization waste liquid to respectively obtain high-quality liquid sulfur with the purity of more than or equal to 99.95 wt%; ash with sulphur content less than 0.1 wt%; oils and ash and oil free desulfurization solutions.

In order to achieve the purpose, the invention adopts the technical scheme that: a system for improving the quality of a desulfurization solution and obtaining high quality sulfur comprising: the system comprises a filter unit, a supergravity separator and a preseparator; a filtrate outlet of a filter of the filter unit is connected with a filtrate inlet of the supergravity separator; the ash-containing solution outlet and the bottom liquid sulfur outlet of the pre-separator are mixed together and connected with the inlets of the filters or respectively connected with the inlets of different filters.

Furthermore, the filter unit comprises a filter, a filtrate assisting tank, a filtrate assisting pump, a discharge tank and a discharge pump, wherein an overflow outlet of the filter is connected with an overflow inlet of the filtrate assisting tank, a filtrate outlet of the filter is connected with an overflow inlet of the filtrate assisting tank, and a filtrate assisting outlet of the filtrate assisting tank is connected with a to-be-filtered liquid inlet of the filter through the filtrate assisting pump; a discharge outlet of the discharge groove is connected with a liquid inlet to be filtered of the filter through a discharge pump; the discharge outlet of the filter is connected with the discharge inlet of the discharge groove.

Further, the filter is a vertical filter or a horizontal filter; the vertical filter is of a vertical cylindrical structure and a lower conical structure, the upper shell is provided with a connecting flange, the bottom of the vertical filter is provided with a slag discharge valve, and the flange of the upper shell of the vertical filter is connected so as to be convenient for the maintenance of a filter plate in the filter; the horizontal filter is of a horizontal cylindrical structure, the front shell is provided with a hydraulic fastening flange, and the rear shell of the flange is pushed backwards through hydraulic pressure to discharge slag, so that the structural form is convenient for overhauling and maintenance of the filter plate in the filter after slag discharge; the shell of the filter adopts a steam jacket for heat preservation.

Furthermore, a plurality of filter plates are arranged in parallel in the filter, the filter plates are circular or rectangular, the filter plates are of a hollow structure, filter screens are arranged on two sides of the filter plates, metal frames are arranged on the periphery of the filter plates, the filter screens are hermetically connected with the peripheral metal frames, a filtrate outlet interface is arranged at the bottom of each filter plate, and the filtrate outlet interface of each filter plate is hermetically connected with a filtrate collecting outlet pipe; the auxiliary filter cake completely covers the screen surfaces on both sides of each filter plate. The heated liquid to be filtered enters the filter machine and flows between the filter plates, the filtrate (one or more of liquid sulfur, oil, soluble salts and water) enters the inner space of the filter plates through the auxiliary filter cake and the filter screen, enters the filtrate outlet manifold through the filtrate outlet interface and then leaves the filter machine, and the ash and slag are intercepted on the auxiliary filter cake, so that the removal of the ash and slag in the desulfurization waste liquid is realized.

Furthermore, the filter is provided with a to-be-filtered liquid inlet, a filtrate outlet, a discharge outlet, a slag discharge outlet (the outlet is only arranged on the vertical filter), an overflow outlet, a compressed air vibration slag discharge interface, a steam inlet of a steam jacket and a steam condensate outlet.

Furthermore, the number of the filter machines is multiple, a plurality of filter machines are connected in parallel for operation, and continuous filtration can be realized by configuring the plurality of filter machines; when the filter is a single filter, an intermediate storage tank is required to be arranged for the liquid to be filtered because continuous and uninterrupted filtration cannot be realized.

Further, when the filters are used for series operation, liquid sulfur with higher purity can be produced, and the use requirements of different market segments are met.

When the ash content in the desulfurization waste liquid is low (generally lower than 0.1 wt%), a conventional horizontal bed filter available in the market can be adopted to filter the heated desulfurization waste liquid; the horizontal bed filter has simple structure, small filtering area and short filtering period.

Further, the filtering period of the single filter is operated according to the sequence period of qualified auxiliary filter cake establishment → filtering → deslagging → qualified filter cake establishment; when the qualified auxiliary filter cake is established, a to-be-filtered liquid inlet in front of the filter is closed through a pipeline valve, a filtrate inlet of a supergravity separator or a filtrate inlet of a liquid-sulfur separator is connected with a discharge tank and a discharge pump through the pipeline valve, discharge flushing is closed through the pipeline valve, a filtrate outlet of the filter is closed and is connected with an overflow inlet of a filtrate assisting tank, the filtrate assisting liquid is sent into the filter by a filtrate assisting pump, when the to-be-filtered liquid returns to the filtrate assisting tank from the overflow inlet of the filtrate assisting tank through an overflow outlet of the filter, the overflow outlet of the filter is closed and is connected with the overflow inlet of the filtrate assisting tank, the filtrate outlet of the filter is opened and is connected with the overflow inlet of the filtrate assisting tank, and the qualified filter cake is established until the ash content in the filtrate is less than 0.05 wt%; when the single filter is used for filtering, the single filter is closed through a pipeline valve and is connected with a filtrate assisting tank, a filtrate assisting pump, a discharge tank and a discharge pump, the discharge flushing is closed through the pipeline valve, and the filtrate to be filtered flows through a filtrate inlet and a filtrate outlet of the filter to realize the filtering; when the filter is used for discharging slag, a to-be-filtered liquid inlet in front of the filter is closed through a pipeline valve, a filtrate inlet of a supergravity separator or a filtrate inlet of a liquid-sulfur separator are closed through the pipeline valve and are connected with a filtrate assisting tank and a filtrate assisting pump, the pipeline valve is used for opening discharge materials and flushing, liquid sulfur flows into a discharge tank along with flushing liquid, after qualified filter cakes of the filter are built, the discharge materials in the discharge tank are discharged, and then the discharge pumps send the discharged materials back to the filter for filtering.

Furthermore, the upper part of the filtrate assisting tank is in a vertical cylinder shape, the lower part of the filtrate assisting tank is in a conical shape, a stirring paddle is arranged in the filtrate assisting tank and is driven by a motor, a filter aid filling port is arranged at the top of the filtrate assisting tank, a liquid sulfur inlet (or hot oil-containing solution) and an overflow inlet are arranged on the side surface of the filtrate assisting tank, and a filtrate assisting outlet is arranged at the bottom of the filtrate assisting tank; the filtrate-assisting tank is insulated by a steam jacket, and a steam inlet and a condensate outlet are arranged on the steam jacket; when the hot oil-containing solution is used for replacing solid sulfur or liquid sulfur in the filtrate assisting tank, a stirring paddle is not needed, and the solution in the filtrate assisting tank, the filter aid and the active carbon are uniformly stirred in a circulating manner by using a filter aid pump. The filter aid tank can also be added with solid sulfur to replace liquid sulfur, and the solid sulfur is filled through a filter aid filling port.

Furthermore, the filter aid consists of sulfur or solution, a filter aid and activated carbon powder (black), wherein the filter aid is diatomite powder or clay powder and is prepared by mixing different grades (particle sizes), and the activated carbon powder (black) with the specific selection of the particle size is used for representing the particle size of typical ash to be separated in the liquid to be filtered.

Furthermore, the upper part of the discharge groove is in a vertical cylindrical shape, the lower part of the discharge groove is in a conical shape, a stirring paddle is arranged in the discharge groove, the stirring paddle is driven by a motor, a discharge inlet is formed in the side surface of the stirring paddle, and a discharge outlet is formed in the bottom of the stirring paddle; the discharging groove is insulated by a steam jacket, and a steam inlet and a condensate outlet are arranged on the steam jacket. The discharge groove can adopt a structure completely the same as the filtrate assisting groove, and the two are mutually standby.

Furthermore, the supergravity separator is of a vertical cylindrical structure, and a plurality of micro cyclone separation pipes are arranged inside the supergravity separator; the side surface of the hypergravity separator is provided with a filtrate inlet, the top and the bottom of the hypergravity separator are respectively provided with an outlet, and the hypergravity separator is divided into three closed cavities from top to bottom by the three interfaces (the filtrate inlet, the top outlet and the bottom outlet), namely an overflow cavity positioned in a top outlet area, a feeding cavity positioned in a middle feeding area and a bottom flow cavity positioned in a bottom outlet area. Filtrate enters the middle feeding cavity and then tangentially enters the micro cyclone separation tubes through the guide tube, under the action of strong centrifugal force (supergravity), the filtrate in each micro cyclone separation tube forms a downward outer cyclone and an upward inner cyclone, liquid sulfur with high density enters the outer cyclone, flows out from the bottom outlet of each micro cyclone separation tube after being converged and enters the underflow cavity, and all the converged liquid sulfur and a small amount of oil-containing solution are discharged from the bottom underflow cavity outlet; and the residual oil-containing solution with low density enters the inner cyclone, enters the overflow cavity from the overflow port at the top of each micro cyclone separation pipe, and all the collected residual oil-containing solution is discharged from the outlet of the overflow cavity at the top. The supergravity separator is arranged in front of the liquid sulfur separator, so that the specification of the low liquid sulfur separator can be reduced.

Further, the pre-separator is of a vertical cylindrical structure and can adopt one or more of the following three feeding materials:

the preseparator is suitable for feeding and is desulfurization waste liquid: the side surface of the pre-separator is provided with a desulfurization waste liquid inlet and an ash-containing solution outlet, the top of the pre-separator is provided with a hot oil-containing solution outlet, the bottom of the pre-separator is provided with a liquid sulfur outlet, the four interfaces (the desulfurization waste liquid inlet, the ash-containing solution outlet, the hot oil-containing solution outlet and the liquid sulfur outlet) divide the pre-separator into three areas from top to bottom according to different densities, the top of the pre-separator is an oil-containing solution outlet area, the middle of the pre-separator is a desulfurization waste liquid feeding area and an ash-containing solution extracting area, and the bottom of the pre-separator is a liquid sulfur outlet area; the diameter of the liquid sulfur area is about 30-100% of the diameter of the upper area; the desulfurization waste liquid inlet and the area below the desulfurization waste liquid inlet are insulated by a steam jacket, and the steam jacket is provided with a steam inlet and a condensate outlet; the ash-containing liquid outlet is a horizontal pipe outlet pipeline or a pipe section which is horizontal and then vertical. The submerged filter pump is arranged on the vertical pipe section which is horizontal and vertical, so that the length of the ash residue pipeline is shortened.

Or, a preseparator suitable for feeding sulfur paste and molten sulfur: the side surface of the pre-separator is provided with a hot oil-containing solution outlet and an ash-containing solution outlet, the top of the pre-separator is provided with a feed inlet, the bottom of the pre-separator is provided with a liquid sulfur outlet, the pre-separator is divided into four areas from top to bottom by the four interfaces, the top of the pre-separator is a feed area, the upper part of the side surface is an oil-containing solution outlet area, the middle part of the pre-separator is an ash-containing solution extraction area, and the bottom of the pre-separator is a liquid sulfur outlet area; the diameter of the liquid sulfur area is about 30-100% of the diameter of the upper area; the feed inlet and the area below the feed inlet are insulated by a steam jacket, and a steam inlet and a condensate outlet are arranged on the steam jacket; the ash-containing liquid outlet is a horizontal pipe outlet pipeline or a pipe section which is horizontal and then vertical. The submerged filter pump is arranged on the vertical pipe section which is horizontal and vertical, so that the length of the ash residue pipeline is shortened.

Or, a preseparator suitable for feeding molten sulfur: the side surface of the pre-separator is provided with an ash-containing solution outlet, the top of the pre-separator is provided with a feed inlet, the bottom of the pre-separator is provided with a liquid sulfur outlet, the pre-separator is divided into three areas from top to bottom by the three interfaces, the top of the pre-separator is a feed area, the middle upper part of the pre-separator is an ash-containing solution extraction area, and the bottom of the pre-separator is a liquid sulfur outlet area; the diameter of the liquid sulfur area is about 30-100% of the diameter of the upper area; the feed inlet and the area below the feed inlet are insulated by a steam jacket, and a steam inlet and a condensate outlet are arranged on the steam jacket; the ash-containing liquid outlet is a horizontal pipe outlet pipeline or a pipe section which is horizontal and then vertical. The submerged filter pump is arranged on the vertical pipe section which is horizontal and vertical, so that the length of the ash residue pipeline is shortened.

Furthermore, the liquid sulfur discharged from the bottom of the pre-separator can be independently sent into a filter for filtering, so that high-quality liquid sulfur can be directly obtained, and the liquid sulfur can also not enter a supergravity separator and/or a liquid sulfur separator.

Furthermore, the preseparator can adopt a plurality of parallel operation, thereby being convenient for adapting to different raw materials; for example, one of the two parallel operations may be used to feed the desulfurization waste liquid, one may be used to feed the sulfur paste and/or the solid molten sulfur, or three parallel operations may be used to feed the desulfurization waste liquid, one may be used to feed the sulfur paste, and one may be used to feed the solid molten sulfur.

Further, when treating a desulfurization waste liquid or a sulfur paste using different desulfurization catalysts, it is preferable to separately heat, filter, and separate the desulfurization waste liquid or the sulfur paste, and solutions containing different catalysts should not be mixed.

The invention relates to a process and a system for improving the quality of a desulfurization solution and obtaining high-quality sulfur, wherein the process is continuous, stable and reliable, and compared with the prior art, the process has the following advantages:

1) the invention can obtain high-quality liquid sulfur (liquid sulfur for short) with the purity of more than or equal to 99.95 wt%.

Heating the desulfurization waste liquid, then filtering the desulfurization waste liquid in a filter, separating filtrate in hypergravity separation after ash residues are removed, separating a solution at an outlet at the top of the hypergravity separation in an oil-liquid separator, separating a solution at an outlet at the bottom of the hypergravity separation in a liquid-sulfur separator, separating the solution at the outlet at the top of the liquid-sulfur separator in the oil-liquid separator, returning a desulfurization solution which is separated by the oil-liquid separator and does not contain ash residues and oils to a desulfurization system, and obtaining high-quality liquid sulfur at the bottom of the liquid-sulfur separator, wherein the purity of the high-quality liquid sulfur is more than or equal to 99.95 wt%; or directly separating the filtrate in a liquid sulfur separator, separating the solution at the outlet of the top of the liquid sulfur separator in an oil-liquid separator, returning the desulfurized solution which is separated by the oil-liquid separator and does not contain ash and oil to a desulfurization system, and obtaining high-quality liquid sulfur at the bottom of the liquid sulfur separator, wherein the purity of the high-quality liquid sulfur is more than or equal to 99.95 wt%.

The desulfurized waste liquid after the desulfurized waste liquid heater can also be fed into a preseparator firstly, the hot oily solution at the top of the preseparator is fed into a desulfurized waste liquid heat exchanger, the ash-containing solution in the middle of the preseparator and the liquid sulfur at the bottom can be mixed together and fed into a filter for filtration or respectively fed into different filters for filtration, so that high-quality liquid sulfur can be obtained, and the purity is more than or equal to 99.95 wt%.

The sulfur paste and the molten sulfur enter the pre-separator through a hopper chute, the hot oil-containing solution on the side surface of the upper part of the pre-separator enters a cooler, the ash-containing solution in the middle of the pre-separator and the liquid sulfur at the bottom can be mixed together and sent into a filter to be filtered or respectively sent into different filters to be filtered, so that high-quality liquid sulfur can be obtained, and the purity is more than or equal to 99.95 wt%.

The molten sulfur enters from the pre-separator through the hopper chute, the ash-containing solution at the upper middle part of the pre-separator and the liquid sulfur at the bottom can be mixed together and sent into the filter for filtering or respectively sent into different filters for filtering, so that high-quality liquid sulfur can be obtained, and the purity is more than or equal to 99.95 wt%.

2) The invention can obtain the desulfurization solution without ash and oil, and the desulfurization solution returns to the desulfurization system to supplement the lost liquid of the desulfurization system and reduce the consumption of the desulfurization catalyst, thereby improving the quality of the desulfurization solution of the desulfurization system.

3) The sulfur content in the filtered ash is less than 0.1 wt%, and the ash is sent to an ash recovery device outside the battery limits.

4) The oil separated by the invention is sent to a separated oil recovery device outside the battery compartment;

5) according to the invention, through the desulfurization waste liquid heat exchanger, the desulfurization waste liquid in front of the desulfurization waste liquid heater indirectly exchanges heat with the hot oil-containing solution in front of the oil-liquid separator, so that heat can be recovered, and energy consumption is reduced; and after heat exchange, the cold oil-containing solution part or the hot oil-containing solution part before the oil-liquid separator is sent into the desulfurization waste liquid before the desulfurization waste liquid heat exchanger, or the hot oil-containing solution part is directly sent into the desulfurization waste liquid before the desulfurization waste liquid heater, or part of liquid sulfur is sent into the to-be-filtered liquid before the filter, so that the reliable long-period operation of the stabilizing device is facilitated.

The solid sulfur, the diatomite powder or the clay powder, the activated carbon powder, the filtrate pump, the discharge pump and the horizontal bed filter are all publicly available in the market.

Drawings

FIG. 1 is a flow chart of a process for improving the quality of a desulfurization solution and obtaining high-quality sulfur in example 1.

FIG. 2 is a flow chart of a process for improving the quality of a desulfurization solution and obtaining high-quality sulfur in example 2.

FIG. 3 is a flow chart of a process for improving the quality of a desulfurization solution and obtaining high-quality sulfur in example 3.

FIG. 4 is a flow chart of a process for improving the quality of a desulfurization solution and obtaining high-quality sulfur according to example 4.

FIG. 5 is a flow chart of a process for improving the quality of a desulfurization solution and obtaining high-quality sulfur in example 5.

Wherein the reference numerals are respectively:

1-desulfurization waste liquid heater, 2-vertical filter, 3-horizontal filter, 4-filtrate-assisting tank, 5-filtrate-assisting pump, 6-discharge tank, 7-discharge pump, 8-hypergravity separator, 9-liquid sulfur separator, 10-oil-liquid separator, 11-preseparator, 12-filter pump, 13-desulfurization waste liquid heat exchanger, 14-filter feed valve, 15-hypergravity separator filtrate feed valve, 16-filtrate-assisting pump outlet valve, 17-filter overflow valve, 18-filtrate-assisting reflux valve, 19-sampling valve, 20-discharge pump outlet valve, 21-filter discharge valve, 22-flushing valve, 23-slag discharge valve, 24-liquid sulfur separator feed valve, 25-cooler.

Detailed Description

The invention is further illustrated by the following examples:

example 1

The embodiment discloses a process and a system for improving the quality of a desulfurization solution and obtaining high-quality sulfur, and the process and the system are shown in figure 1, and comprise a desulfurization waste liquid heater 1, a horizontal filter 3, a filtrate assisting tank 4, a filtrate assisting pump 5, a discharge tank 6, a discharge pump 7, a supergravity separator 8, a liquid-sulfur separator 9, an oil-liquid separator 10 and a desulfurization waste liquid heat exchanger 13. The filter feed valve 14 is a pipeline valve for connecting a desulfurization waste liquid outlet of a desulfurization waste liquid heater 1 with a desulfurization waste liquid inlet of a horizontal filter 3, the hypergravity separator filtrate feed valve 15 is a pipeline valve for connecting a filtrate outlet of the horizontal filter 3 with a filtrate inlet of a hypergravity separator 8, the filtrate pump outlet valve 16 is a pipeline valve for connecting an outlet of a filtrate pump 5 with the desulfurization waste liquid inlet of the horizontal filter 3, the filter overflow valve 17 is a pipeline valve for connecting an overflow outlet of the horizontal filter 3 with an overflow inlet of a filtrate tank 4, the filtrate reflux valve 18 is a pipeline valve for connecting a filtrate outlet of the horizontal filter 3 with an overflow inlet of the filtrate tank 4, the sampling valve 19 is arranged on a filtrate outlet pipeline of the horizontal filter 3, the discharge pump outlet valve 20 is a pipeline valve for connecting an outlet of a discharge pump 7 with the horizontal filter 3 desulfurization waste liquid inlet, and the discharge valve 21 is a pipeline valve for connecting a discharge outlet of the filter 3 with a discharge tank 6, the flushing valve 22 is a pipeline valve for connecting the front pipeline of the desulfurization waste liquid heat exchanger with the desulfurization waste liquid inlet of the horizontal filter 3.

During filtering, the filter feed valve 14 and the supergravity separator filtrate feed valve 15 are opened, and the filtrate pump outlet valve 16, the filter overflow valve 17, the filtrate return valve 18, the sampling valve 19, the discharge pump outlet valve 20, the filter discharge valve 21 and the flushing valve 22 are closed.

A desulfurized waste stream from a desulfurization system comprising the following components: 2-3 wt% of sulfur (solid suspended sulfur), 0.2-0.4 wt% of ash, 0.2-1.5 g/L of oil, soluble salt and water.

The desulfurization waste liquid sequentially flows through a desulfurization waste liquid heat exchanger 13 and a desulfurization waste liquid heater 1 to enter a horizontal filter 3, and the temperature of the desulfurization waste liquid at the outlet of the desulfurization waste liquid heater 1 is 133-136 ℃; the filtrate leaves the horizontal filter 3 and enters a hypergravity separator 8, all liquid sulfur and a small amount of oil-containing solution are discharged from the bottom of the hypergravity separator 8 and enter a liquid sulfur separator 9, and the residual hot oil-containing solution escapes from the top of the hypergravity separator 8 and enters a desulfurization waste liquid heat exchanger 13; high-quality liquid sulfur is discharged from the bottom of the liquid sulfur separator 9, part of the liquid sulfur enters the filtrate assisting tank 4, and hot oil-containing solution escapes from the top of the liquid sulfur separator 9 and enters the desulfurization waste liquid heat exchanger 13; in the desulfurization waste liquid heat exchanger 13, after the heat exchange between the oil-containing solution and the desulfurization waste liquid, part of the oil-containing solution is sent into the desulfurization waste liquid before the desulfurization waste liquid heat exchanger 13, the rest of the oil-containing solution enters the oil-liquid separator 10, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to an oil separation recovery device outside a battery compartment; the steam heats the desulfurization waste liquid in the desulfurization waste liquid heater 1.

When the qualified auxiliary filter cake is built, closing a filter feed valve 14, a supergravity separator filtrate feed valve 15, a filter aid reflux valve 18, a sampling valve 19, a discharge pump outlet valve 20, a filter discharge valve 21 and a flushing valve 22; respectively feeding the liquid sulfur, kieselguhr powder with different particle sizes and a small amount of activated carbon powder into a filtrate assisting tank 4, and uniformly mixing under the stirring of a stirring paddle; the filtrate in the filtrate assisting tank 4 is sent into the horizontal filter 3 by the filtrate assisting pump 5; after the filtrate is returned to the filtrate-assisting tank 4 from the overflow port of the horizontal filter 3 through the overflow port of the filtrate-assisting tank 4 by the opened overflow valve 17 of the filter, the overflow valve 17 of the filter is closed, the return valve 18 of the filtrate-assisting is opened, so that the filtrate-assisting liquid flows through each filter plate in the horizontal filter 3, the liquid sulfur passes through the filter plate and returns to the filtrate-assisting tank 4, the diatomite and the active carbon are intercepted on the filter plate to form an auxiliary filter cake, the liquid sulfur sample returned to the filtrate-assisting tank 4 is taken by the sampling valve 19 for assay analysis, and the qualified auxiliary filter cake is established until the liquid sulfur contains no active carbon.

When discharging slag, closing the filter feed valve 14, the supergravity separator filtrate feed valve 15, the filtrate pump outlet valve 16, the filter overflow valve 17, the filtrate return valve 18, the sampling valve 19, the discharge pump outlet valve 20 and the flushing valve 22, and opening the filter discharge valve 21. Discharging residual liquid at the bottom of the horizontal filter 3 into a slag discharge groove 6 through a filter discharge valve 21, opening a flushing valve 22, flushing the bottom of the horizontal filter 3 by hot oil-containing solution from the front of the desulfurization waste liquid heat exchanger 13, and closing the filter discharge valve 21 and the flushing valve 22 after flushing is finished; opening a shell at the rear part of the flange of the horizontal filter 3 through a hydraulic mechanism, assisting compressed air to vibrate and discharge slag, and tightly closing the flange shell of the horizontal filter 3 through the hydraulic mechanism after the slag discharge is finished; after the horizontal filter 3 is qualified and the filter cake is built, opening the outlet valve 20 of the discharge pump and the filtrate feed valve 15 of the hypergravity separator, and completely feeding the discharged materials in the slag discharge groove 6 back to the horizontal filter 3 for filtering through the outlet valve 20 of the discharge pump 7; the ash discharged by the horizontal filter 3 is sent to an ash recovery device outside the battery limits.

Example 2

The embodiment discloses a process and a system for improving the quality of a desulfurization solution and obtaining high-quality sulfur, and the process and the system are shown in figure 2, and comprise a desulfurization waste liquid heater 1, a horizontal filter 3, a filtrate assisting tank 4, a filtrate assisting pump 5, a discharge tank 6, a discharge pump 7, a supergravity separator 8, a liquid-sulfur separator 9, an oil-liquid separator 10, a pre-separator 11, a vertical filter pump 12 and a cooler 25. The filter feed valve 14 is a pipeline valve for connecting an ash-containing solution outlet of a filter pump 12 and a liquid sulfur outlet at the bottom of a pre-separator 11 with a to-be-filtered solution inlet of a horizontal filter 3, the hypergravity separator filtrate feed valve 15 is a pipeline valve for connecting a filtrate outlet of the horizontal filter 3 with a filtrate inlet of a hypergravity separator 8, the filtrate pump outlet valve 16 is a pipeline valve for connecting an outlet of a filtrate pump 5 and a to-be-filtered solution inlet of the horizontal filter 3, the filter overflow valve 17 is a pipeline valve for connecting an overflow outlet of the horizontal filter 3 with an overflow inlet of a filtrate tank 4, the filtrate reflux valve 18 is a pipeline valve for connecting a filtrate outlet of the horizontal filter 3 with an overflow inlet of the filtrate tank 4, the sampling valve 19 is an upper valve for a filtrate outlet pipeline of the horizontal filter 3, the discharge pump outlet valve 20 is a pipeline valve for connecting an outlet of a discharge pump 7 and a to-be-filtered solution inlet of the horizontal filter 3, and the discharge valve 21 is a discharge outlet of the filter 3 and a discharge tank 6 inlet, the flushing valve 22 is a pipeline valve for connecting the front pipeline of the cooler 25 with the inlet of the horizontal filter 3 to be filtered.

During filtering, the filter feed valve 14 and the supergravity separator filtrate feed valve 15 are opened, and the filtrate pump outlet valve 16, the filter overflow valve 17, the filtrate return valve 18, the sampling valve 19, the discharge pump outlet valve 20, the filter discharge valve 21 and the flushing valve 22 are closed.

A desulfurized waste stream from a desulfurization system comprising the following components: 5-6 wt% of sulfur (solid suspended sulfur), 0.6-0.8 wt% of ash, 0.3-4 g/L of oil, soluble salt and water.

Enabling the desulfurized waste liquid to flow through a desulfurized waste liquid heater 1 and enter a preseparator 11, wherein the temperature of the desulfurized waste liquid at an outlet of the desulfurized waste liquid heater 1 is 135-137 ℃; the hot oil-containing solution at the top of the pre-separator 11 enters a cooler 25, the ash-containing solution in the middle of the pre-separator 11 and liquid sulfur discharged from the bottom of the pre-separator are sent to a horizontal filter 3 to be filtered, the filtrate leaves the horizontal filter 3 and enters a supergravity separator 8, all the liquid sulfur and a small amount of oil-containing solution are discharged from the bottom of the supergravity separator 8 and enter a liquid sulfur separator 9, and the residual hot oil-containing solution escapes from the top of the supergravity separator 8 and enters the cooler 25; discharging high-quality liquid sulfur from the bottom of the liquid sulfur separator 9, allowing part of the liquid sulfur to enter the filtrate assisting tank 4, and allowing the hot oil-containing solution to escape from the top of the liquid sulfur separator 9 and enter the cooler 25; before the cooler 25, part of the hot oil-containing solution is sent into the desulfurization waste liquid before the desulfurization waste liquid heater 1, the rest hot oil-containing solution is sent into the cooler 25 for cooling, the cold oil-containing solution is sent into the oil-liquid separator 10, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to an oil separation recovery device outside the battery limits; the steam heats the desulfurization waste liquid in the desulfurization waste liquid heater 1.

When the qualified auxiliary filter cake is built, closing a filter feed valve 14, a supergravity separator filtrate feed valve 15, a filter aid reflux valve 18, a sampling valve 19, a discharge pump outlet valve 20, a filter discharge valve 21 and a flushing valve 22; respectively feeding liquid sulfur, argil powder with different particle sizes and a small amount of activated carbon powder into a filtrate assisting tank 4, and uniformly mixing under the stirring of a stirring paddle; the filtrate in the filtrate assisting tank 4 is sent into the horizontal filter 3 by the filtrate assisting pump 5; after the filtrate is returned to the filtrate-assisting tank 4 from the overflow port of the horizontal filter 3 through the overflow port of the filtrate-assisting tank 4 by the opened overflow valve 17 of the filter, the overflow valve 17 of the filter is closed, the return valve 18 of the filtrate-assisting is opened, so that the filtrate-assisting liquid flows through each filter plate in the horizontal filter 3, the liquid sulfur passes through the filter plate and returns to the filtrate-assisting tank 4, the diatomite and the active carbon are intercepted on the filter plate to form an auxiliary filter cake, the liquid sulfur sample returned to the filtrate-assisting tank 4 is taken by the sampling valve 19 for assay analysis, and the qualified auxiliary filter cake is established until the liquid sulfur contains no active carbon.

When discharging slag, closing the filter feed valve 14, the supergravity separator filtrate feed valve 15, the filtrate pump outlet valve 16, the filter overflow valve 17, the filtrate return valve 18, the sampling valve 19, the discharge pump outlet valve 20 and the flushing valve 22, and opening the filter discharge valve 21. Discharging residual liquid at the bottom of the horizontal filter 3 into a slag discharge groove 6 through a filter discharge valve 21, opening a flushing valve 22, flushing the bottom of the horizontal filter 3 by hot oil-containing solution from the front of a cooler 25, and closing the filter discharge valve 21 and the flushing valve 22 after flushing is finished; opening a shell at the rear part of the flange of the horizontal filter 3 through a hydraulic mechanism, assisting compressed air to vibrate and discharge slag, and tightly closing the shell flange of the horizontal filter 3 through the hydraulic mechanism after the slag discharge is finished; after the horizontal filter 3 is qualified and the filter cake is built, opening the outlet valve 20 of the discharge pump and the filtrate feed valve 15 of the hypergravity separator, and completely feeding the discharged materials in the slag discharge groove 6 back to the horizontal filter 3 for filtering through the outlet valve 20 of the discharge pump 7; the ash discharged by the horizontal filter 3 is sent to an ash recovery device outside the battery limits.

Example 3

The embodiment discloses a process and a system for improving the quality of a desulfurization solution and obtaining high-quality sulfur, and the process and the system are shown in figure 3, and comprise a desulfurization waste liquid heater 1, a vertical filter 2, a filtrate assisting tank 4, a filtrate assisting pump 5, a discharge tank 6, a discharge pump 7, a liquid-sulfur separator 9, an oil-liquid separator 10 and a desulfurization waste liquid heat exchanger 13. The filter feed valve 14 is a pipeline valve for connecting a desulfurization waste liquid outlet of a desulfurization waste liquid heater 1 with a desulfurization waste liquid inlet of a vertical filter 2, the liquid sulfur separator filtrate feed valve 24 is a pipeline valve for connecting a filtrate outlet of the vertical filter 2 with a filtrate inlet of a liquid sulfur separator 9, the filtrate-assisting pump outlet valve 16 is a pipeline valve for connecting an outlet of a filtrate-assisting pump 5 with a desulfurization waste liquid inlet of the vertical filter 2, the filter overflow valve 17 is a pipeline valve for connecting an overflow outlet of the vertical filter 2 with an overflow inlet of a filtrate-assisting tank 4, the filtrate-assisting reflux valve 18 is a pipeline valve for connecting a filtrate outlet of the vertical filter 2 with an overflow inlet of the filtrate-assisting tank 4, the sampling valve 19 is an upper valve for a filtrate outlet pipeline of the vertical filter 2, the discharge pump outlet valve 20 is a pipeline valve for connecting an outlet of a discharge pump 7 with a desulfurization waste liquid inlet of the vertical filter 2, and the discharge valve 21 is a discharge inlet connecting pipeline valve for connecting a discharge outlet of the vertical filter 2 with a discharge tank 6, the flushing valve 22 is a pipeline valve for connecting a hot oil-containing solution pipeline in front of the desulfurization waste liquid heat exchanger with the desulfurization waste liquid inlet of the vertical filter 2, and the slag discharging valve 23 is a slag discharging valve of the vertical filter 2.

During filtering, the filter feed valve 14 and the liquid sulfur separator filtrate feed valve 24 are opened, and the filtrate pump outlet valve 16, the filter overflow valve 17, the filtrate return valve 18, the sampling valve 19, the discharge pump outlet valve 20, the filter discharge valve 21, the flushing valve 22 and the slag discharge valve 23 are closed.

A desulfurized waste stream from a desulfurization system comprising the following components: 8-10 wt% of sulfur (solid suspended sulfur), 0.7-1.1 wt% of ash, 6-8 g/L of oil, soluble salt and water.

The desulfurization waste liquid sequentially flows through a desulfurization waste liquid heat exchanger 13 and a desulfurization waste liquid heater 1 to enter a vertical filter 2, and the temperature of the desulfurization waste liquid at the outlet of the desulfurization waste liquid heater 1 is 136-138 ℃; the filtrate leaves the vertical filter 2 and enters a liquid sulfur separator 9, high-quality liquid sulfur is discharged from the bottom of the liquid sulfur separator 9, part of the liquid sulfur enters a filtrate assisting tank 4, and hot oil-containing solution escapes from the top of the liquid sulfur separator 9 and enters a desulfurization waste liquid heat exchanger 13; in the desulfurization waste liquid heat exchanger 13, after the heat exchange between the hot oil-containing solution and the desulfurization waste liquid, part of the cold oil-containing solution is sent into the desulfurization waste liquid before the desulfurization waste liquid heat exchanger 13, the rest of the cold oil-containing solution enters the oil-liquid separator 10, the separated desulfurization solution without ash and oil returns to the desulfurization system, and the separated oil is sent to an oil separation and recovery device outside the battery limits; the steam heats the desulfurization waste liquid in the desulfurization waste liquid heater 1.

When the qualified auxiliary filter cake is built, closing a filter feed valve 14, a liquid sulfur separator filtrate feed valve 24, a filter aid reflux valve 18, a sampling valve 19, a discharge pump outlet valve 20, a filter discharge valve 21 and a flushing valve 22; respectively feeding the liquid sulfur, kieselguhr powder with different particle sizes and a small amount of activated carbon powder into a filtrate assisting tank 4, and uniformly mixing under the stirring of a stirring paddle; the filtrate in the filtrate assisting tank 4 is sent into the vertical filter 2 by the filtrate assisting pump 5; after the filtrate is returned to the filtrate-assisting tank 4 from the overflow port of the vertical filter 2 through the overflow port of the filtrate-assisting tank 4 by the opened overflow valve 17 of the filter, the overflow valve 17 of the filter is closed, the return valve 18 of the filtrate-assisting is opened, so that the filtrate-assisting liquid flows through each filter plate in the vertical filter 2, the liquid sulfur passes through the filter plate and returns to the filtrate-assisting tank 4, the diatomite and the active carbon are intercepted on the filter plate to form an auxiliary filter cake, the liquid sulfur sample returned to the filtrate-assisting tank 4 is taken by the sampling valve 19 for assay analysis, and the qualified auxiliary filter cake is established until the liquid sulfur contains no active carbon.

When discharging slag, closing the filter feed valve 14, the liquid sulfur separator filtrate feed valve 24, the filtrate pump outlet valve 16, the filter overflow valve 17, the filtrate return valve 18, the sampling valve 19, the discharge pump outlet valve 20 and the flushing valve 22, and opening the filter discharge valve 21. Discharging residual liquid at the bottom of the vertical filter 2 into a slag discharge groove 6 through a filter discharge valve 21, opening a flushing valve 22, flushing the bottom of the vertical filter 2 by hot oil-containing solution from the front of the desulfurization waste liquid heat exchanger 13, and closing the filter discharge valve 21 and the flushing valve 22 after flushing is finished; opening a slag discharge valve 23 of the vertical filter 2, discharging slag by assisting compressed air vibration, and tightly closing the slag discharge valve 23 after finishing slag discharge; after the vertical filter 2 is qualified and the filter cake is built, opening the outlet valve 20 of the discharge pump and the filtrate feed valve 24 of the liquid sulfur separator, and feeding all the discharged materials in the slag discharge groove 6 back to the vertical filter 2 for filtering through the outlet valve 20 of the discharge pump 7; the ash discharged by the vertical filter 2 is sent to an ash recovery device outside the battery limits.

Example 4

The embodiment discloses a process and a system for improving the quality of a desulfurization solution and obtaining high-quality sulfur, and the system comprises a horizontal filter 3, a filtrate tank 4, a filtrate pump 5, a discharge tank 6, a discharge pump 7, a hypergravity separator 8, a liquid-sulfur separator 9, an oil-liquid separator 10, a pre-separator 11, a vertical filter pump 12 and a cooler 25, as shown in figure 4. The filter feed valve 14 is a pipeline valve for connecting an ash-containing solution outlet of a filter pump 12 and a liquid sulfur outlet at the bottom of a pre-separator 11 with a to-be-filtered solution inlet of a horizontal filter 3, the hypergravity separator filtrate feed valve 15 is a pipeline valve for connecting a filtrate outlet of the horizontal filter 3 with a filtrate inlet of a hypergravity separator 8, the filtrate pump outlet valve 16 is a pipeline valve for connecting an outlet of a filtrate pump 5 and a to-be-filtered solution inlet of the horizontal filter 3, the filter overflow valve 17 is a pipeline valve for connecting an overflow outlet of the horizontal filter 3 with an overflow inlet of a filtrate tank 4, the filtrate reflux valve 18 is a pipeline valve for connecting a filtrate outlet of the horizontal filter 3 with an overflow inlet of the filtrate tank 4, the sampling valve 19 is an upper valve for a filtrate outlet pipeline of the horizontal filter 3, the discharge pump outlet valve 20 is a pipeline valve for connecting an outlet of a discharge pump 7 and a to-be-filtered solution inlet of the horizontal filter 3, and the discharge valve 21 is a discharge outlet of the filter 3 and a discharge tank 6 inlet, the flushing valve 22 is a pipeline valve for connecting the hot oil-containing solution pipeline in front of the cooler 25 with the inlet of the horizontal filter 3 to be filtered.

During filtering, the filter feed valve 14 and the supergravity separator filtrate feed valve 15 are opened, and the filtrate pump outlet valve 16, the filter overflow valve 17, the filtrate return valve 18, the sampling valve 19, the discharge pump outlet valve 20, the filter discharge valve 21 and the flushing valve 22 are closed.

Adding 45-55% of sulfur paste containing water from a hopper chute at the top of the pre-separator 11, wherein the temperature of liquid sulfur at the lower part of the pre-separator 11 is 135-137 ℃; hot oil-containing solution on the side surface of the upper part of the pre-separator 11 enters a cooler 25, ash-containing solution in the middle of the pre-separator 11 is pumped out by a filter pump 12 and is mixed with liquid sulfur discharged from the bottom of the pre-separator to be sent into a horizontal filter 3 for filtering, filtrate leaves the horizontal filter 3 and enters a hypergravity separator 8, all the liquid sulfur and a small amount of oil-containing solution are discharged from the bottom of the hypergravity separator 8 to enter a liquid sulfur separator 9, and the rest hot oil-containing solution escapes from the top of the hypergravity separator 8 and enters the cooler 25; high-quality liquid sulfur is discharged from the bottom of the liquid sulfur separator 9, and hot oil-containing solution escapes from the top of the liquid sulfur separator 9 and enters the cooler 25; part of the hot oil-containing solution in front of the cooler 25 is sent into the liquid to be filtered after the filter pump 12 and in front of the feed valve 14 of the filter 3; in the cooler 25, after part of the hot oil-containing solution is cooled by cooling water, the hot oil-containing solution enters the oil-liquid separator 10, the separated desulfurization solution without ash and oil returns to a desulfurization system, and the separated oil is sent to an oil separation and recovery device outside the battery compartment; part of the hot oily solution before the cooler 25 is sent to the tank 4 for filter aid.

When the qualified auxiliary filter cake is built, closing a filter feed valve 14, a supergravity separator filtrate feed valve 15, a filter aid reflux valve 18, a sampling valve 19, a discharge pump outlet valve 20, a filter discharge valve 21 and a flushing valve 22; part of the hot oil-containing solution in front of the cooler 25, diatomite powder with different particle sizes and a small amount of activated carbon powder are respectively sent into the filtrate assisting tank 4 and are pumped back by the filtrate assisting pump 5 (namely, the tank bottom liquid of the filtrate assisting tank 4 is circularly returned to the filtrate assisting tank 4 by the filtrate assisting pump 5 to be stirred) until the mixture is uniformly mixed; the filtrate in the filtrate assisting tank 4 is sent into the horizontal filter 3 by the filtrate assisting pump 5; after the filtrate is returned to the filtrate-assisting tank 4 from the overflow port of the horizontal filter 3 through the overflow port of the filtrate-assisting tank 4 by the opened overflow valve 17 of the filter, the overflow valve 17 of the filter is closed, the filtrate-assisting return valve 18 is opened, so that the filtrate-assisting liquid flows through each filter plate in the horizontal filter 3, the solution passes through the filter plate and returns to the filtrate-assisting tank 4, the diatomite and the active carbon are intercepted on the filter plate to form an auxiliary filter cake, the solution sample returned to the filtrate-assisting tank 4 is taken by the sampling valve 19 for assay analysis, and the qualified auxiliary filter cake is established until the solution contains no active carbon.

When discharging slag, closing the filter feed valve 14, the supergravity separator filtrate feed valve 15, the filtrate pump outlet valve 16, the filter overflow valve 17, the filtrate return valve 18, the sampling valve 19, the discharge pump outlet valve 20 and the flushing valve 22, and opening the filter discharge valve 21. Discharging residual liquid at the bottom of the horizontal filter 3 into a slag discharge groove 6 through a filter discharge valve 21, opening a flushing valve 22, flushing the bottom of the horizontal filter 3 by hot oil-containing solution from the front of a cooler 25, and closing the filter discharge valve 21 and the flushing valve 22 after flushing is finished; opening a shell at the rear part of the flange of the horizontal filter 3 through a hydraulic mechanism, assisting compressed air to vibrate and discharge slag, and tightly closing the shell flange of the horizontal filter 3 through the hydraulic mechanism after the slag discharge is finished; after the horizontal filter 3 is qualified and the filter cake is built, opening the outlet valve 20 of the discharge pump and the filtrate feed valve 15 of the hypergravity separator, and completely feeding the discharged materials in the slag discharge groove 6 back to the horizontal filter 3 for filtering through the outlet valve 20 of the discharge pump 7; the ash discharged by the horizontal filter 3 is sent to an ash recovery device outside the battery limits.

Example 5

The embodiment discloses a process and a system for improving the quality of a desulfurization solution and obtaining high-quality sulfur, and the system comprises a horizontal filter 3, a filtrate assisting tank 4, a filtrate assisting pump 5, a discharge tank 6, a discharge pump 7, a pre-separator 11 and a vertical filter pump 12, as shown in figure 5. The filter feed valve 14 is a pipeline valve for connecting an ash-containing solution outlet of the filter pump 12 and a liquid sulfur outlet at the bottom of the preseparator 11 with a to-be-filtered liquid inlet of the horizontal filter 3, the filter feed valve 15 is a pipeline valve for connecting a filtrate outlet of the horizontal filter 3, the filtrate outlet valve 16 of the filtrate pump is a pipeline valve for connecting an outlet of the filtrate pump 5 with a to-be-filtered liquid inlet of the horizontal filter 3, the overflow valve 17 of the filter is a pipeline valve for connecting an overflow outlet of the horizontal filter 3 with an overflow inlet of the filtrate tank 4, the filtrate reflux valve 18 of the filtrate pump is a pipeline valve for connecting a filtrate outlet of the horizontal filter 3 with an overflow inlet of the filtrate tank 4, the sampling valve 19 is an upper valve for connecting a filtrate outlet pipeline of the horizontal filter 3, the outlet valve 20 of the discharge pump is a pipeline valve for connecting an outlet of the discharge pump 7 with a to-be-filtered liquid inlet of the horizontal filter 3, and the discharge valve 21 of the filter is a discharge inlet connecting pipeline valve for connecting a discharge outlet of the discharge tank 6 of the filter 3.

During filtering, the feed valve 14 of the filter 3 and the filtrate outlet valve 15 of the filter 3 are opened, and the filtrate pump outlet valve 16, the filter overflow valve 17, the filtrate return valve 18, the sampling valve 19, the discharge pump outlet valve 20 and the filter discharge valve 21 are closed.

Solid molten sulfur is added from a hopper chute at the top of a pre-separator 11, the temperature of liquid sulfur at the lower part of the pre-separator 11 is 138-141 ℃, ash-containing solution (the solution is the liquid sulfur) in the middle of the pre-separator 11 is pumped out by a filter pump 12 and is mixed with the liquid sulfur discharged from the bottom of the pre-separator 11 and then is sent into a horizontal filter 3 for filtering, high-quality liquid sulfur is discharged from a filtrate outlet of the horizontal filter 3, part of the liquid sulfur enters a filtrate assisting tank 4, and part of the liquid sulfur is sent into liquid to be filtered in front of a feed valve 14 of the filter 3. Steam heats the solid molten sulfur in the preseparator 11 jacket.

And when the qualified auxiliary filter cake is built, closing the feed valve 14 of the filter 3, the filtrate outlet valve 15 of the filter 3, the auxiliary filtrate return valve 18, the sampling valve 19, the discharge pump outlet valve 20 and the filter discharge valve 21. Respectively feeding liquid sulfur, argil powder with different particle sizes and a small amount of activated carbon powder into a filtrate assisting tank 4, and uniformly mixing under the stirring of a stirring paddle; the filtrate in the filtrate assisting tank 4 is sent into the horizontal filter 3 by the filtrate assisting pump 5; after the filtrate is returned to the filtrate-assisting tank 4 from the overflow port of the horizontal filter 3 through the overflow port of the filtrate-assisting tank 4 by the opened overflow valve 17 of the filter, the overflow valve 17 of the filter is closed, the return valve 18 of the filtrate-assisting is opened, so that the filtrate-assisting liquid flows through each filter plate in the horizontal filter 3, the liquid sulfur passes through the filter plate and returns to the filtrate-assisting tank 4, the diatomite and the active carbon are intercepted on the filter plate to form an auxiliary filter cake, the liquid sulfur sample returned to the filtrate-assisting tank 4 is taken by the sampling valve 19 for assay analysis, and the qualified auxiliary filter cake is established until the liquid sulfur contains no active carbon.

When discharging slag, the feed valve 14 of the filter 3, the filtrate outlet valve 15 of the filter 3, the outlet valve 16 of the filtrate pump, the overflow valve 17 of the filter, the filtrate return valve 18, the sampling valve 19 and the outlet valve 20 of the discharge pump are closed, and the discharge valve 21 of the filter is opened. Discharging residual liquid at the bottom of the horizontal filter 3 into a discharge tank 6 through a filter discharge valve 21, closing the filter discharge valve 21 after discharging is finished, opening a shell at the rear part of a flange of the horizontal filter 3 through a hydraulic mechanism, discharging slag by assisting compressed air vibration, and tightly closing the shell flange of the horizontal filter 3 through the hydraulic mechanism after discharging slag is finished; after the horizontal filter 3 is qualified and the filter cake is built, opening the outlet valve 20 of the discharge pump and the outlet valve 15 of the filter 3 filtrate, and feeding all the discharged materials in the slag discharge groove 6 back to the horizontal filter 3 for filtering through the discharge pump 7 and the outlet valve 20 of the discharge pump; the ash discharged by the horizontal filter 3 is sent to an ash recovery device outside the battery limits.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.