1. A microwave drying method for a honeycomb SCR denitration catalyst is characterized by comprising the following steps:

(1) closely arranging the honeycomb SCR denitration catalyst wet blanks on a conveyor belt, conveying the honeycomb SCR denitration catalyst wet blanks into a microwave box body by the conveyor belt to receive microwave radiation, introducing air flow into the microwave box body at the same time, and drying for 5min to finish a pre-drying process;

(2) keeping the temperature within 30 ℃, drying for 15-30min, and finishing drying shrinkage shaping, wherein the water loss rate is 10-15%;

(3) reducing the humidity of the introduced air to below 50%, increasing the temperature and keeping the temperature within 60 ℃, and drying for 10-15min to finish the drying process.

2. The microwave drying method for the honeycomb SCR denitration catalyst according to claim 1, wherein the distance between two adjacent honeycomb SCR denitration catalyst wet blanks is 7-9 mm.

3. The microwave drying method for the honeycomb SCR denitration catalyst according to claim 1, wherein the temperature of the introduced air is 20-30 ℃, the humidity is 35-100%, and the wind speed is 0-30 m/s.

4. The microwave drying method for the honeycomb SCR denitration catalyst of claim 1, wherein the air flow introduced into the microwave box has a plurality of air flows, and the flow directions of the plurality of air flows are staggered to form a counter flow.

5. The utility model provides a microwave drying device for honeycomb SCR denitration catalyst, its characterized in that, includes microwave box (2) and conveyer belt (5), conveyer belt (5) are sent into the wet base of honeycomb SCR denitration catalyst (1) and are dried inside microwave box (2), be equipped with matrix array pipe (3) on the relative both sides face of microwave box (2), matrix array pipe (3) are through a plurality of connectors (6) and air-supply line (7) and play tuber pipe (8) intercommunication, any side of the relative both sides face of microwave box (2) all communicates has air-supply line (7) and goes out tuber pipe (8), and air-supply line (7) of any side correspond the setting with the play tuber pipe (8) of opposite side.

6. The microwave drying device for the honeycomb SCR denitration catalyst according to claim 5, wherein the air inlet pipe (7) and the air outlet pipe (8) are specifically arranged as follows: on any side of two opposite side surfaces of the microwave box body (2), n air inlet pipes (7) and n air outlet pipes (8) are adjacent and staggered, and n is more than or equal to 1.

7. The microwave drying device for the honeycomb SCR denitration catalyst according to claim 5, wherein the top of the matrix array tube (3) is higher than the top end of the honeycomb SCR denitration catalyst wet blank (1), and the bottom of the matrix array tube (3) is at the same level with the conveyor belt (5) or lower than the conveyor belt (5).

8. The microwave drying device for the honeycomb SCR denitration catalyst according to claim 5, wherein the aperture of the matrix array tube (3) is not more than half wavelength of microwave radiation, and the aperture ratio is more than or equal to 80%.

9. The microwave drying device for the honeycomb SCR denitration catalyst according to claim 5, wherein an expansion box body (4) is further connected to the inlet and outlet of the conveyor belt (5) of the microwave box body (2), and the top of the expansion box body (4) is lower than the top of the microwave box body (2) and higher than the top of the honeycomb SCR denitration catalyst wet blank (1).

10. The microwave drying device for the honeycomb SCR denitration catalyst according to claim 5, wherein a baffle (9) is further arranged in the microwave box body (2), the height of the baffle (9) is higher than the top end of the honeycomb SCR denitration catalyst wet blank (1), and the height of the baffle (9) is above the matrix array tube (3).

Background

The preparation method of the honeycomb denitration catalyst of the vanadium-tungsten-titanium system comprises the following steps: the preparation method comprises the steps of firstly blending, mixing and pugging, extruding into a honeycomb-shaped wet blank, then wrapping the wet blank by a paper box, placing the wet blank in a drying furnace, slowly drying by controlling the temperature and the humidity (the drying period is generally 7-11 days), removing the wrapped paper box after the wet blank is shaped, exposing the blank to carry out convection drying, and calcining the dried honeycomb body to form the final honeycomb-type flue gas denitration catalyst unit.

The microwave drying technology is widely used in the fields of light industry, food, chemical industry and agriculture, and is successfully applied to the industries of ceramic and cordierite honeycomb carriers, but the honeycomb ceramic and cordierite material and the smoke denitration catalyst of the vanadium-tungsten-titanium system have essential difference on the absorption of microwave radiation in the aspects of material and shape. Firstly, the ceramic and cordierite materials belong to wave-transparent materials, the endurable temperature is higher, and water in a wet blank absorbs all microwaves in the microwave drying process. TiO in vanadium-tungsten-titanium honeycomb denitration catalyst material₂TiO content over 75%₂The material belongs to a semiconductor material and is a material capable of absorbing microwaves, and due to the fact that the mud material contains inflammable organic matters, the highest temperature is about 60 ℃ generally when a conventional packaging carton is slowly dried, when microwave drying is used, heat is easy to accumulate inside a pore channel of a honeycomb denitration catalyst wet blank, an energy accumulation effect is generated, the temperature is continuously increased, cracking of the catalyst is easy to occur, and burning is caused under the serious condition.

In addition, due to TiO₂Is microwave absorbing material, and is heated by microwaveUneven water loss can be caused in the drying process, the front surface receiving microwave radiation loses water first and begins to shrink, the whole drying process is carried out layer by layer along the direction of the microwave radiation, synchronous drying cannot be realized, and unsynchronized drying and water loss and inconsistent blank body shrinkage are caused to cause blank body cracking.

Secondly, as shown in fig. 1, the honeycomb SCR denitration catalyst wet blank is cuboid, the end face is square, has edges and edges, is different from a cylindrical ceramic honeycomb, has a circular cross section, is more uniform in all directions when receiving microwave radiation, and has no place for intensively receiving microwave radiation on the surface; the honeycomb denitration catalyst with the square cross section receives microwave radiation in all directions at four corners and is relatively concentrated, the dielectric loss degree of the honeycomb denitration catalyst is higher than that of other places, the honeycomb denitration catalyst is easy to dry at the places fast, and the drying at other places is relatively slow, so that the corners are cracked.

It is due to the above problems that the doped metal oxide V is limited₂O₅、WO₃、MO_X(M is rare earth elements such as Ce, Mo, Mn and the like) and semiconductor material TiO₂Based on the above background, we provide a microwave drying method for honeycomb SCR denitration catalyst and a device used in microwave drying to solve the above problems.

Disclosure of Invention

The invention aims to: the microwave drying method and the microwave drying device for the honeycomb SCR denitration catalyst can shorten the drying time from 7-11 days to 1 hour, greatly improve the drying efficiency, shorten the drying time, ensure more uniform drying, avoid the phenomenon that a catalyst wet blank is easy to generate stress fracture, have less occupied area of the whole equipment, have high energy utilization rate, and are more energy-saving and environment-friendly.

The technical scheme adopted by the invention is as follows:

in order to achieve the above object, the present invention provides a microwave drying method for a honeycomb SCR denitration catalyst, comprising the steps of:

(1) closely arranging the honeycomb SCR denitration catalyst wet blanks on a conveyor belt, conveying the honeycomb SCR denitration catalyst wet blanks into a microwave box body by the conveyor belt to receive microwave radiation, introducing air flow into the microwave box body at the same time, and drying for 5min to finish a pre-drying process;

(2) keeping the temperature within 30 ℃, drying for 15-30min, and finishing drying shrinkage shaping, wherein the water loss rate is 10-15%;

(3) reducing the humidity of the introduced air to below 50%, increasing the temperature and keeping the temperature within 60 ℃, and drying for 10-15min to finish the drying process.

Preferably, the distance between the two adjacent honeycomb SCR denitration catalyst wet blanks is 7-9 mm.

Preferably, the temperature of the introduced air is 20-30 ℃, the humidity is 35-100%, and the wind speed is 0-30 m/s.

Preferably, the air flow introduced into the microwave oven body has a plurality of air flows, and the flow directions of the plurality of air flows are staggered to form a counter flow.

The invention also provides a microwave drying device for the honeycomb SCR denitration catalyst, which comprises a microwave box body and a conveyor belt, wherein the conveyor belt conveys a honeycomb SCR denitration catalyst wet blank into the microwave box body for drying, two opposite side surfaces of the microwave box body are provided with matrix array pipes, the matrix array pipes are communicated with an air inlet pipe and an air outlet pipe through a plurality of connectors, any one side of the two opposite side surfaces of the microwave box body is communicated with the air inlet pipe and the air outlet pipe, and the air inlet pipe on any one side is arranged corresponding to the air outlet pipe on the opposite side.

Preferably, the air inlet pipe and the air outlet pipe are specifically arranged as follows: on any side of two opposite side surfaces of the microwave box body, n air inlet pipes and n air outlet pipes are adjacent and staggered, and n is more than or equal to 1.

Preferably, the top of the matrix array tube is higher than the top of the honeycomb SCR denitration catalyst wet blank, and the bottom of the matrix array tube and the conveyor belt are at the same horizontal plane or lower than the conveyor belt, so that the introduced air flow can effectively enter all pore channels of the honeycomb SCR denitration catalyst wet blank and four surfaces which effectively contact the outer wall after passing through the matrix array tube.

Preferably, the aperture of the matrix array tube is not more than half wavelength of microwave radiation, the aperture ratio is more than or equal to 80%, and the method can ensure that wind introduced into the microwave box body uniformly enters the pore channels of the honeycomb SCR denitration catalyst wet blank, can restrain microwaves in the box body, and does not leak.

Preferably, the inlet and outlet of the conveyor belt of the microwave box body are further connected with an expansion box body, the top of the expansion box body is lower than the top of the microwave box body and higher than the top of the honeycomb SCR denitration catalyst wet blank, so that the honeycomb SCR denitration catalyst wet blank can enter a microwave box body radiation area through the conveyor belt, and the microwave radiation can be effectively prevented from leaking out.

Preferably, the connector comprises a square opening end, a transition section and a round opening end, the round opening end is communicated with the air inlet pipe or the air outlet pipe, the square opening end is communicated with the matrix array pipe, the square opening end is communicated with the round opening end through the transition section, and the diameter of the square opening end is larger than that of the round opening end.

Preferably, a baffle is further arranged in the microwave box body, the height of the baffle is higher than the top end of a wet blank of the honeycomb SCR denitration catalyst, and the height of the baffle is higher than that of the matrix array tube.

In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:

1. according to the invention, a microwave drying and ventilation drying mode is adopted, compared with a common drying mode, the period is shortened to be within 1 hour from 7-11 days, on the basis of microwave drying, heat in the pore channels of the honeycomb SCR denitration catalyst wet blank is effectively taken away through ventilation, and the temperature rise caused by heat concentration in the process of medium loss during microwave drying and the stress rupture in the wet blank structure caused by the heat concentration are eliminated.

2. Because the length and the volume of the honeycomb SCR denitration catalyst wet blank are larger, a certain pressure drop exists in the ventilation process, the wind speed is attenuated to a certain degree when wind enters the pore channel and flows out from the tail of the pore channel, and the temperature and the humidity of the wind flowing out from the tail of the pore channel are higher than those of the wind flowing out from the inlet and have a certain temperature and humidity difference, so that the phenomenon that the drying and water loss rate is reduced gradually is easily generated at the air inlet end along the air outlet end direction of the catalyst wet blank, and the phenomenon that the drying and water loss rate is reduced is uneven in the water loss shrinkage process, so that the blank body is cracked; the invention ensures that wind energy entering the microwave box body can uniformly enter the pore channels of the honeycomb SCR denitration catalyst wet blank by arranging a plurality of strands of air flows in the directions to form cross convection, so that both ends of the catalyst wet blank can be uniformly ventilated, and the process problems that both ends of the blank are easy to crack and deform in the microwave drying process are solved.

3. According to the invention, the expansion box bodies are arranged at the two ends of the microwave box body, so that microwave radiation can be effectively prevented from leaking out while the honeycomb SCR denitration catalyst wet blank can smoothly enter the radiation area of the microwave box body through the conveyor belt.

4. According to the invention, the baffle plate parallel to the plane of the conveyor belt is arranged above the matrix array tube, and the baffle plate can prevent water in the microwave drying process from flowing in the height direction of the microwave box body, so that all lost water flows out of the matrix array tube on one side, the consistency of the water loss of the wet blank in the direction is kept, and the cracking of the upper surface of the honeycomb denitration catalyst wet blank caused by the too fast water loss is prevented.

5. According to the invention, the aperture size of the matrix array tube arranged on the microwave box body is limited within a half wavelength range not exceeding microwave radiation, so that the wind introduced into the microwave box body can be ensured to enter the pore channel of the honeycomb SCR denitration catalyst wet blank more uniformly through the arrangement of the matrix array tube, and the limitation of the aperture size can inhibit microwaves in the box body, thereby avoiding microwave radiation leakage.

6. The existing drying equipment of the conventional honeycomb denitration catalyst is a drying furnace, the heat source of the drying furnace is steam, and the capacity is 8000m³The occupied area of the drying furnace is about 1600m calculated per year²2-3 ten thousand cartons are needed for packaging, and the packaging box is used for circulation and drying, wherein the drying period is generally 7-11 days; with the same productivity of 8000m³The field of the microwave drying equipment is about 400m per year²About, the wet blank drying period of a single honeycomb denitration catalyst can be shortened to be within 1 hour, and the drying period is not requiredThe paper box is wrapped for drying, the energy consumption is only electricity, the heat energy converted by the electromagnetic energy almost completely acts on the wet blank materials, the energy utilization rate is higher, and the energy consumption can be saved by 200 plus 300 yuan/m³Compared with the conventional drying oven which needs to utilize fossil fuel to burn to generate steam, the microwave drying method is more environment-friendly and does not pollute the environment.

Drawings

The invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a schematic structural diagram of a honeycomb SCR denitration catalyst wet blank;

FIG. 2 is a schematic view of a microwave drying apparatus according to the present invention;

FIG. 3 is a schematic structural diagram II of the microwave drying device of the present invention;

FIG. 4 is a schematic structural diagram of the microwave cabinet after being connected with the expansion cabinet and the conveyor belt;

FIG. 5 is a schematic view of the structure of a catalyst wet blank as it travels on a conveyor belt;

fig. 6 is a schematic structural diagram of the connecting head.

Labeled as: 1-honeycomb SCR denitration catalyst wet blank, 2-microwave box, 3-matrix array pipe, 4-expansion box, 5-conveyor belt, 6-connector, 601-square opening end, 602-transition section, 603-round opening end, 7-air inlet pipe, 8-air outlet pipe and 9-baffle.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings, and it is to be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The embodiment provides a microwave drying method for a honeycomb SCR denitration catalyst, which comprises the following steps:

(1) closely arranging the honeycomb SCR denitration catalyst wet blanks on a conveyor belt, conveying the honeycomb SCR denitration catalyst wet blanks into a microwave box body by the conveyor belt to receive microwave radiation, introducing air flow into the microwave box body at the same time, and drying for 5min to finish a pre-drying process;

(2) keeping the temperature within 30 ℃, drying for 15-30min, and finishing drying shrinkage shaping, wherein the water loss rate is 10-15%; specifically, in the drying shrinkage shaping stage, the drying temperature is controlled within 30 ℃ by reducing the microwave power or reducing the ventilation temperature and simultaneously increasing the humidity;

(3) after shrinkage and shaping, the microwave power can be gradually increased, the humidity of the introduced air is reduced to below 50%, the temperature is increased and kept within 60 ℃, and the drying process is finished after 10-15min of drying.

According to the invention, a microwave drying and ventilation drying mode is adopted, compared with a common drying mode, the period is shortened to be within 1 hour from 7-11 days, on the basis of microwave drying, heat in the pore channels of the honeycomb SCR denitration catalyst wet blank is effectively taken away through ventilation, and the temperature rise caused by heat concentration in the process of medium loss during microwave drying and the stress rupture in the wet blank structure caused by the heat concentration are eliminated.

Preferably, the distance between two adjacent honeycomb SCR denitration catalyst wet blanks is 7-9mm, so that the two honeycomb SCR denitration catalyst wet blanks are closely arranged, and the specific use can be determined according to the aperture of the actual catalyst wet blank.

Preferably, the temperature of the introduced air is 20-30 ℃, the humidity is 35-100%, and the wind speed is 0-30 m/s.

Preferably, the air flow introduced into the microwave oven body has a plurality of air flows, and the flow directions of the plurality of air flows are staggered to form a counter flow.

Because the length and the volume of the honeycomb SCR denitration catalyst wet blank are larger, a certain pressure drop exists in the ventilation process, so that the wind speed is attenuated to a certain degree when wind enters the pore channel and flows out from the tail of the pore channel, and the microwave drying and heating effects are added, the temperature and the humidity of the wind flowing out from the tail of the pore channel are higher than those of the wind flowing out from the inlet, and a certain temperature and humidity difference exists, so that the phenomenon that the drying and water loss rate of the catalyst wet blank decreases along the direction of the wind outlet end at the wind inlet end is easily caused, thereby causing the non-uniformity in the water loss shrinkage process and causing the blank body to crack Deformation and the like.

Example 2

The embodiment provides a microwave drying device for a honeycomb SCR denitration catalyst, which comprises a microwave box body 2 and a conveyor belt 5, wherein the microwave box body 2 is of a cuboid structure and made of stainless steel, microwave feed ports can be arranged at the top or the bottom of the microwave box body 2, or the top and the bottom of the microwave feed ports are arranged at the same time, so that a honeycomb denitration catalyst wet blank receives microwave radiation from two surfaces at the same time for heating, and a plurality of feed ports can be arranged according to the size of the box body so as to ensure the uniformity of microwave field distribution; the feeding mode includes, but is not limited to, rotating a waveguide and a slit antenna, and meanwhile, aiming at the length, the number of holes, the specific gravity and the like of different honeycomb catalyst wet blanks, the precise adjustment can be realized by respectively or simultaneously adjusting the microwave power in different microwave feeding directions;

the honeycomb SCR denitration catalyst wet blank 1 is conveyed to the interior of the microwave box body 2 by the conveyor belt 5 for drying, the conveyor belt 5 and the transmission part are made of wave-transparent materials including but not limited to polytetrafluoroethylene, polypropylene, nylon, organic glass and the like, the conveyor belt is driven by a motor, and the moving speed of the conveyor belt 5 is adjusted within the range of 0-1m/min through the frequency of the motor;

the microwave oven is characterized in that two opposite side faces of the microwave oven body 2 are provided with the matrix array pipes 3, the setting width and height of the matrix array pipes 3 are adjusted according to the length of a catalyst wet blank and the size of the microwave oven body 2, the matrix array pipes 3 are communicated with air inlet pipes 7 and air outlet pipes 8 through a plurality of connectors 6, any one side of the two opposite side faces of the microwave oven body 2 is communicated with the air inlet pipes 7 and the air outlet pipes 8, the air inlet pipes 7 on any one side correspond to the air outlet pipes 8 on the opposite side, preferably, on any one side of the two opposite side faces of the microwave oven body 2, the n air inlet pipes 7 and the n air outlet pipes 8 are adjacent and staggered, and n is larger than or equal to 1.

Specifically, when n is equal to 1, as shown in fig. 2, on one side of the microwave cabinet 2, the air inlet pipes 7 and the air outlet pipes 8 are arranged in such a manner that 1 air inlet pipe 7 is adjacent to 1 air outlet pipe 8, while 1 air outlet pipe 8 is adjacent to 1 air inlet pipe 7 on the opposite side, and this is done in sequence, so as to form cross-convection ventilation.

When n is 2, as shown in fig. 3, the air inlet pipes 7 and the air outlet pipes 8 are arranged on one side of the microwave cabinet 2 in such a manner that 2 air inlet pipes 7 are adjacent to 2 air outlet pipes 8, and 2 air outlet pipes 8 are adjacent to 2 air inlet pipes 7 on the opposite side, so that the arrangement is completed in sequence to form cross-convection ventilation; and so on.

The whole set of microwave drying equipment is arranged in a relatively closed room, an air inlet pipe 7 is connected with a fan, the frequency of the fan can be subjected to frequency conversion adjustment within the range of 0-50Hz, air flow with certain temperature and humidity is introduced into the air inlet pipe 7, the temperature can be controlled by an air conditioner or heating and refrigerating equipment, after the temperature of water is controlled by humidity control, the water is introduced into 1 or more nozzles to be atomized and then sprayed into the air inlet pipe 7, the air inlet pipe 7 is connected with a temperature and humidity controller, and the temperature and humidity controller controls the temperature and humidity of the atomized water entering the air inlet pipe 7 by adopting a heating and refrigerating circulator.

When using, closely arrange honeycomb SCR denitration catalyst wet base 1 and place on conveyer belt 5, send honeycomb SCR denitration catalyst wet base 1 through conveyer belt 5 and send into microwave box 2 inside and receive microwave radiation, at the in-process that carries out microwave drying, the air that lets in has certain temperature, humidity and amount of wind can take away the heat that produces because of receiving microwave radiation in the catalyst wet base pore, has avoided the fracture problem that the heat gathering brought.

Example 3

This embodiment is further preferred on embodiment 2's basis, the top of matrix array pipe 3 is higher than the top of honeycomb SCR denitration catalyst wet base 1, and the bottom of matrix array pipe 3 and conveyer belt 5 are at same horizontal plane or be less than conveyer belt 5 to guarantee that the air current that lets in can effectively get into all tunnels of honeycomb SCR denitration catalyst wet base 1 and four faces of effective contact outer wall behind matrix array pipe 3.

Example 4

In this embodiment, it is further preferable on the basis of embodiment 2 that the aperture of the matrix array tube 3 is not more than half wavelength of microwave radiation, and the aperture ratio is not less than 80%, so that the wind introduced into the microwave box 2 can be ensured to uniformly enter the pore channels of the honeycomb SCR denitration catalyst wet blank 1, and the microwaves can be restrained in the box without leakage.

Example 5

This embodiment is further preferred on embodiment 2's basis, 5 business turn over departments of conveyer belt of microwave box 2 still are connected with an extension box 4, the top of extension box 4 is less than the top of microwave box 2, is higher than the top of honeycomb SCR denitration catalyst wet billet 1 simultaneously, can prevent effectively that the microwave radiation from leaking out when guaranteeing that honeycomb SCR denitration catalyst wet billet 1 can get into microwave box 2 radiation zone through conveyer belt 5 through setting up extension box 4.

Example 6

In this embodiment, it is further preferable that the connector 6 includes a square opening end 601, a transition section 602, and a round opening end 603, the round opening end 603 is communicated with the air inlet pipe 7 or the air outlet pipe 8, the square opening end 601 is communicated with the matrix array pipe 3, the square opening end 601 is communicated with the round opening end 603 through the transition section 602, and the aperture of the square opening end 601 is larger than the aperture of the round opening end 603; can conveniently be connected with air-supply line 7 and play tuber pipe 8 through the setting of round mouth end 603, the setting of square mouth end 601 can conveniently be connected with matrix array pipe 3, the wind that sends air-supply line 7 through connector 6 lets in matrix array pipe 3 from square mouth end 601, let in microwave box 2 evenly, the air current in microwave box 2 also can be evenly in proper order from square mouth end 601 through matrix array pipe 3, changeover portion 602 and round mouth end 603 flow out, get into out tuber pipe 8.

Example 7

In this embodiment, it is further preferable that a baffle 9 is further disposed in the microwave box 2, the height of the baffle 9 is higher than the top end of the wet blank 1 of the honeycomb SCR denitration catalyst, and the height of the baffle 9 is located above the matrix array tube 3; through setting up baffle 9 parallel with conveyer belt 5 plane above matrix array tube 3, the honeycomb catalyst wet base is in the drying process, and the existence of baffle 9 can prevent moisture to the flow of microwave box 2 direction of height to make the whole matrix array tube 3 that flows out of the moisture that looses of one side, keep the moisture of wet base to scatter and disappear in the ascending uniformity of direction, thereby prevent that the upper surface of honeycomb denitration catalyst wet base from because of moisture scatters and splits too fast.

Application example 1

1. Selection of catalyst wet blank: the honeycomb SCR denitration catalyst selected by the embodiment is a wet blank which is just extruded and has the water content of about 25%; 800mm in length, square in cross section, 156mm on a side, 9.2 pitches, 16X 16 holes.

2. Parameter selection and setting: the microwave frequency is 915MHz, and the maximum output power of the microwave source is 60 KW; the width of the conveyor belt is 1000 mm; 2 microwave feed ports are arranged at the top of the microwave box body, are uniformly spaced and symmetrically distributed in the length direction and the width direction of the box body, and feed microwave radiation in a rotary waveguide mode; the conveyor speed was set to 0.2 m/min; the temperature of the ventilated airflow is controlled at 25 ℃, the humidity is set to be 85 percent, and the ventilation is carried out in a ventilation mode shown in figure 2; the whole height of the matrix array tube connected with the air pipe is 170mm, the holes are square, and the side length is 40 mm; a piece of wave-transparent organic glass is flatly laid and arranged in the height direction of the top of the matrix array tube along the width direction of the microwave box body; and 15 variable frequency fans are mounted in total, the maximum power of each fan is 5.5KW, and the fans are connected to the matrix array tube through air pipes.

3. The implementation steps are as follows:

(1) because the microwave drying process can not be carried out in a no-load mode, at the beginning, a finished product obtained after the honeycomb catalyst is calcined and partially soaked is continuously filled in the microwave box body, the conveyor belt is opened, the finished product is conveyed into the microwave box body by using the manipulator stained with the sponge clamping plate, after the finished product is fully paved in the box body, the honeycomb denitration catalyst wet blanks are filled by using the manipulator, the single wet blanks are relatively closely arranged, and the preferred distance is 1 pore diameter (about 8.5 mm).

(2) Pre-drying: the microwave power is set to be 17KW, a microwave power supply is started to carry out microwave transmission, when the microwave power is displayed to be 3-4KW, a fan is started (the frequency of the fan is set to be 16HZ), the temperature of ventilated airflow is controlled to be 25 ℃, the humidity is controlled to be 85%, a conveying belt is started at the same time, and the drying time is 5 min.

(3) Drying, shrinking and shaping: the microwave power is adjusted to 35KW, the fan frequency is adjusted to 20HZ, and after drying time is 30min, the water loss rate of drying shrinkage shaping is measured to be 13%.

(4) And (3) quick drying and dewatering: the microwave power is adjusted to 45KW, the fan frequency is adjusted to 25HZ, the humidity of the introduced air flow is adjusted to 45 percent, the drying time is 15min, and the measured final water content is 4 percent.

Application example 2

1. Selection of catalyst wet blank: the honeycomb SCR denitration catalyst selected by the embodiment is a wet blank which is just extruded and has the water content of about 25%; the length is 1000mm, the section is square, the side length is 156mm, and the pitch is 8.2, namely 18 multiplied by 18 holes.

2. Parameter selection and setting: the microwave frequency is 915MHz, and the maximum output power of the microwave source is 60 KW; the width of the conveyor belt is 1400 mm; 2 microwave feed ports are arranged at the bottom of the microwave box body, are uniformly spaced and symmetrically distributed in the length direction and the width direction of the box body, and feed microwave radiation in a rotary waveguide mode; the conveyor speed was set to 0.3 m/min; the temperature of the ventilated airflow is controlled at 25 ℃, the humidity is set to be 85 percent, and the ventilation is carried out in a ventilation mode shown in figure 2; the whole height of the matrix array tube connected with the air pipe is 170mm, the holes are square, and the side length is 40 mm; a wave-transparent polytetrafluoroethylene plate is flatly laid and arranged in the height direction of the top of the matrix array tube along the width direction of the microwave box body; and 15 variable frequency fans are mounted in total, the maximum power of each fan is 5.5KW, and the fans are connected to the matrix array tube through air pipes.

3. The implementation steps are as follows:

(1) because the microwave drying process can not be carried out in a no-load mode, at the beginning, a finished product obtained after the honeycomb catalyst is calcined and partially soaked is continuously filled in the microwave box body, the conveyor belt is opened, the finished product is conveyed into the microwave box body by using the manipulator stained with the sponge clamping plate, after the finished product is fully paved in the box body, the honeycomb denitration catalyst wet blanks are filled by using the manipulator, the single wet blanks are relatively closely arranged, and the preferred distance is 1 pore diameter (about 7.5 mm).

(2) Pre-drying: the microwave power is set to be 17KW, a microwave power supply is started to carry out microwave transmission, when the microwave power is displayed to be 3-4KW, a fan is started (the frequency of the fan is set to be 17HZ), the temperature of ventilated airflow is controlled to be 25 ℃, the humidity is controlled to be 85%, a conveying belt is started at the same time, and the drying time is 5 min.

(3) Drying, shrinking and shaping: the microwave power is adjusted to 35KW, the fan frequency is adjusted to 20HZ, and after drying time is 30min, the water loss rate of drying shrinkage shaping is measured to be 12%.

(4) And (3) quick drying and dewatering: the microwave power is adjusted to 45KW, the fan frequency is adjusted to 30HZ, the humidity of the introduced air flow is adjusted to 45 percent, the drying time is 15min, and the measured final water content is 5 percent.

Application example 3

1. Selection of catalyst wet blank: the honeycomb SCR denitration catalyst selected by the embodiment is a freshly extruded wet blank with the water content of about 26%; 800mm in length, square in cross-section, 156mm on a side, 7.6 pitches, 20X 20 holes.

2. Parameter selection and setting: the microwave frequency is 915MHz, and the maximum output power of the microwave source is 60 KW; the width of the conveyor belt is 1000 mm; respectively arranging 2 microwave feed ports at the bottom and the top of the microwave box body, and feeding microwave radiation in a rotary waveguide mode; the conveyor speed was set to 0.2 m/min; the temperature of the ventilated airflow is controlled at 25 ℃, the humidity is set to be 85 percent, and the ventilation is carried out in a ventilation mode shown in figure 2; the whole height of the matrix array tube connected with the air pipe is 170mm, the holes are square, and the side length is 40 mm; a wave-transparent polytetrafluoroethylene plate is flatly laid and arranged in the height direction of the top of the matrix array tube along the width direction of the microwave box body; and 15 variable frequency fans are mounted in total, the maximum power of each fan is 5.5KW, and the fans are connected to the matrix array tube through air pipes.

3. The implementation steps are as follows:

(1) because the microwave drying process can not be carried out in a no-load mode, at the beginning, a finished product obtained after the honeycomb catalyst is calcined and partially soaked is continuously filled in the microwave box body, the conveyor belt is opened, the finished product is conveyed into the microwave box body by using the manipulator stained with the sponge clamping plate, after the finished product is fully paved in the box body, the honeycomb denitration catalyst wet blanks are filled by using the manipulator, the single wet blanks are relatively closely arranged, and the preferred distance is 1 pore diameter (about 7 mm).

(2) Pre-drying: the microwave power is set to be 17KW, a microwave power supply is started to carry out microwave transmission, when the microwave power is displayed to be 3-4KW, a fan is started (the frequency of the fan is set to be 17HZ), the temperature of ventilated airflow is controlled to be 25 ℃, the humidity is controlled to be 85%, a conveying belt is started at the same time, and the drying time is 5 min.

(3) Drying, shrinking and shaping: the microwave power is adjusted to 35KW, the fan frequency is adjusted to 21HZ, and after the drying time is 15min, the water loss rate of drying shrinkage shaping is measured to be 15%.

(4) And (3) quick drying and dewatering: the microwave power is adjusted to 45KW, the fan frequency is adjusted to 30HZ, the humidity of introduced air flow is adjusted to 45%, the drying time is 10min, and the final drying water loss rate is 3%.

TABLE 1 drying data of 3 application examples

As can be seen from the table I, the microwave drying method of the invention has short drying time, can complete the whole drying process within one hour, has good drying effect, and does not generate cracking phenomenon on the dried product.

The existing drying equipment for the conventional honeycomb denitration catalyst is a drying furnace, and the heat source of the drying furnace is steam. With a production capacity of 8000m³The occupied area of the drying furnace is about 1600m calculated per year²And 2-3 ten thousand cartons are needed for wrapping the honeycomb catalyst wet blank unit, and the honeycomb catalyst wet blank unit is circulated, used and dried. The drying period is generally 7-11 days; with the same productivity of 8000m³The field of the microwave drying equipment is about 400m per year²And about, the drying period of the wet blank of the single honeycomb denitration catalyst can be shortened to be within 1 hour. And the drying is carried out without paper box wrapping, the energy consumption is only electricity, and the electricity isThe heat energy converted by the magnetic energy almost completely acts on the wet blank materials, the energy utilization rate is higher, and the energy consumption can be saved by 200-³。

The conventional drying oven is slower in heating by using steam, the heating and cooling processes need longer time, the microwave drying heating speed is higher, the power is continuously adjustable, the control is convenient, the microwave power supply can be used immediately, and compared with the conventional drying oven which needs to generate steam by burning fossil fuel, the microwave drying oven is more environment-friendly and does not pollute the environment.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill 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; these modifications and substitutions do not cause the essence of the corresponding technical solution to depart from the scope of the technical solution of the embodiments of the present invention, and are intended to be covered by the claims and the specification of the present invention.