1. A high-efficiency biological method for treating organic wastewater is characterized by comprising the following steps:

(1) culturing the drogue et drogue: planting drooping umbellate grasses with roots in a water-permeable container basin, standing in a humid environment, and obtaining the cultured drooping umbellate grasses after the roots of the drooping umbellate grasses grow out;

(2) the array design of the drogue grasses: the method comprises the steps of determining the area of an array and determining the number of the cultivated droguella; the array area is S ═ alpha_COD)^1.3400; the number of the cultivated droughhaired stems is N ═ S.rho;

(3) and (3) installing the drogue grasses in an array: selecting a corresponding field as a treatment pool according to the calculated array area, installing an overflow port and a circulating pump at the tail part of the treatment pool, and fixing the cultured drogue pennywort herb in the treatment pool to finish the installation;

(4) and (3) organic wastewater treatment: introducing the organic wastewater into the head of the treatment tank, starting a circulating pump until the standard treatment is completed and discharging.

2. The efficient biological method for treating organic wastewater according to claim 1, wherein in the step (1), through holes are formed in the periphery and the bottom of the water-permeable container basin, and the diameter of each through hole is 0.8-1 cm.

3. The high efficiency biological method for treating organic wastewater according to claim 1, wherein in the step (1), the water permeable container basin is filled with graded sand, river mud or pond mud and introduction materials; and 4/5 filled into the volume of the water permeable container basin and submerges the roots of the droughtonite parasol by 3-5 cm.

4. The efficient biological method for treating organic wastewater according to claim 1, wherein in the step (1), the standing time or the clean water curing time is 7-10 d, and then the organic wastewater is introduced into the treatment tank.

5. The efficient biological method for treating organic wastewater according to claim 1, wherein in the step (3), the bottom of the treatment tank is subjected to anti-seepage treatment, and 30-50 cm-grade sand and stone, river mud or pond mud and introduction materials are paved in the treatment tank; or ridge ridges are formed in the treatment tank by using the same materials and are used for planting the droughhaired groundsel herb.

6. The high efficiency biological method for treating organic wastewater according to claim 1, wherein in the step (3), the length-width ratio of the treatment tank is more than or equal to 20, and a 'ditch' shape is formed, so that the organic wastewater is ensured to slowly flow through the root area of the drogue opening grass and is completely treated.

7. The efficient biological method for treating organic wastewater according to claim 4, wherein the design value of daily treatment capacity is 1 to 1000L/m²·d。

8. The efficient biological method for treating organic wastewater according to claim 1, further comprising a mowing step of drogue grasses, specifically comprising: and (5) cutting when the drooping cymbidium herbs grow to 1.5-1.6 m.

9. The efficient biological method for treating organic wastewater according to claim 1, further comprising a mowing step of drogue grasses, specifically comprising: and (3) cutting the drooping bevel grass once every month in the period of 5-10 months of vigorous growth of the drooping bevel grass every year.

10. The efficient biological method for treating organic wastewater according to claim 1, further comprising the growth temperature control requirement of the droughhaired bevel herb, wherein the water temperature is controlled to be 20-30 ℃.

Background

At present, no technical method for directly treating high-concentration organic wastewater (COD is 1000-5000 mg/L) and realizing standard discharge in one step exists.

The existing method is to carry out anaerobic fermentation after pretreatment of higher concentration organic wastewater (such as cow dung urine, pig dung water, chicken manure, flushing water, slaughter sewage, human dung urine, municipal domestic sewage and the like) and straw sawdust. The produced biogas is used for life production; after the generated byproduct biogas residues and biogas slurry are separated, the biogas residues can be further used for producing organic fertilizer. After anaerobic fermentation, the COD concentration of the biogas slurry can be reduced to below 2000mg/L, but the COD concentration can be reduced to below 300mg/L only by long-time multiple aeration or dilution, and then the biogas slurry can be used for farmland irrigation; if the discharge is required to reach the standard, the COD concentration is required to be further reduced to be below 100mg/L or 50 mg/L.

In the method, the defects of complex fermentation process, large equipment investment, high energy consumption of aeration operation, large wetland treatment area, sewage infiltration, torrential rain overflow and the like or the risk of secondary pollution exist. Therefore, a simple and direct treatment method which is energy-saving, economical, efficient, ecological, cyclic and sustainable in utilization is urgently needed.

Based on the technical scheme, the invention is provided.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a high-efficiency biological method for treating organic wastewater. The method for treating the organic wastewater has the capability of quickly, efficiently and directly treating the organic wastewater with higher concentration, and the drooping cymbidium has high growth speed, large biomass and high conversion efficiency, and is not possessed by other submerged plants (such as the watermifoil), floating plants (such as the water hyacinth and the like), emergent aquatic plants (such as the reed, the wild rice stem, the calamus and the like) and hygrophytes (such as the polygonum hydropiper and the like).

The inventor finds that the drooping umbrella grass has the capability of resisting higher organic wastewater load through observation tests and literature reference. During the test, the pig farm biogas slurry which is not subjected to solid-liquid separation is directly introduced (the COD of the test biogas slurry reaches 2013mg/L), the normal growth of the pig farm biogas slurry is not influenced, and the pig farm biogas slurry can rapidly grow in the temperature environment above 20 ℃. The drooping mushroom grass has rich nutrition and good palatability, and is suitable for being used as green feed or silage of pigs, cattle and sheep. In order to fully exert the characteristic of the droughhaired bevel herb, the proposal of the invention is to provide a high-efficiency biological method for treating organic wastewater, which comprises the following steps:

(1) culturing the drogue et drogue: planting drooping umbellate grasses with roots in a water-permeable container basin, standing in a humid environment, and obtaining the cultured drooping umbellate grasses after the roots of the drooping umbellate grasses grow out;

(2) the array design of the drogue grasses: the method comprises the steps of determining the area of an array and determining the number of the cultivated droguella; the array area is S ═ alpha_COD)^1.3400; the number of the cultivated droughhaired stems is N ═ S.rho;

(3) and (3) installing the drogue grasses in an array: selecting a corresponding field as a treatment pool according to the calculated array area, installing an overflow port and a circulating pump at the tail part of the treatment pool, and fixing the cultured drogue pennywort herb in the treatment pool to finish the installation;

(4) and (3) organic wastewater treatment: introducing the organic wastewater into the head of the treatment tank, starting a circulating pump until the standard treatment is completed and discharging.

It is emphasized that in an emergency situation, the circulating pump is started to recirculate the organic wastewater which is not treated to reach the standard to the water inlet until the quality of tail water reaches the standard. The device is a protection design and is used for emergency guarantee under the conditions of rainstorm and sewage concentration mutation, and organic sewage in the device is prevented from being discharged due to substandard treatment.

In the stage of culturing the drooping umbrella grass, selecting the vigorous drooping umbrella grass (the plant height is 50-100 cm), planting the vigorous drooping umbrella grass into a water-permeable container basin (such as a gardening basin, the periphery and the bottom of the water-permeable container basin are perforated, the aperture is 0.8-1 cm, and the perforated area proportion is 10-20%) with the depth of 25-30 cm and the diameter of 25-30 cm or the side length is 25cm, filling graded sandstone, river mud or pond mud and a seeding material to 20-24 cm, enabling the graded sandstone, the river mud or pond mud to submerge 3-5 cm of the drooping umbrella grass root, standing the water in the basin side or ditch for 7-10 days, keeping the water moist, and obtaining the cultured drooping umbrella grass after the drooping umbrella grass root grows out of the basin hole through the hole, wherein the cultured drooping umbrella grass can be used for subsequent installation and use, and then introducing organic wastewater into a treatment pool.

Wherein, the weight percentage of the introduced substance adopted by the patent is more than 95 percent of coarse grinding powder (granularity is 0.01-1.0 mm) of oyster shells, scallop shells and the like and microbial active bacteria powder in a certain weight ratio. Mainly provides a microorganism source and nutrients (such as Ca element and the like) for the growth of microorganisms for the quick start of the device.

Similarly, the number and the array area of the composition of the cultured droughtonia is also crucial to the treatment effect. The inventor verifies for a long time that the array area (S) and the COD concentration (alpha) of the organic wastewater are found_COD) There is a certain fitting relationship, i.e. S ═ (α)_COD)^1.3/400, and R²1(R denotes data variance). Wherein the unit of the array area S is m²COD concentration of organic wastewater alpha_CODThe unit of (b) is mg/L.

And within the determined array area S, the required number N of the cultured droughhaired parasol grasses is S.rho, wherein rho represents the array density, namely the number of the cultured droughhaired parasol grasses required to be arranged in unit area, and the unit is as follows: per m². In the application of the invention, the array density is the optimum value obtained by the inventor after tests, and rho is 8-12 pieces/m²。

Specifically, assume that α of organic wastewater to be treated_CODThe array area S and the number N of the cultivated drogue mushroom are shown in Table 1 when the array area S is 100mg/L, 1000mg/L and 2000mg/L respectively.

TABLE 1

αCOD(mg/L)	100	1000	2000
				After treatment alphaCOD(mg/L)	≤50	≤50	≤50
S(m2)	1	20	49
				N (pieces)	8～12	160～240	392～588

As can be seen from Table 1, when the organic waste water α to be treated_CODAt 100mg/L, it is only required to be at 1m²8-12 pieces of cultured drooping umbrellas are arranged in the array area, and then the treatment of the organic wastewater can be completed; when the organic wastewater to be treated is alpha_CODAt 1000mg/L, it is only necessary to be at 20m²160-240 pieces of cultured drooping umbrellas are arranged in the array area, and the treatment of the organic wastewater can be completed; when the organic wastewater to be treated is alpha_CODAt 2000mg/L, it is only necessary to be at 49m²392 to 588 pieces of drogue grasses are arranged in the array area, and then the treatment of the organic wastewater can be completed. And the organic wastewater alpha after the practical test of the inventor is treated_CODCan be reduced to below 50 mg/L. The invention is directed to alpha_CODThe organic wastewater with the concentration of 100-5000 mg/L has the treatment capacity. It is emphasized that when the organic waste water load is α_CODWhen the amount exceeds the design value of the apparatus, the solution should be diluted for use.

In the installation process of the paraquat array (pool or ditch), the length-width ratio of each treatment ditch is ensured to be more than or equal to 20 times, and the organic wastewater is ensured to be fully treated.

In the installation process of the arrays (pools or ditches) of the droughtonia, selecting a field which cannot be submerged by rainwater, leveling the land according to the calculated array area, digging to a depth of 30-50 cm, paving an impermeable membrane to prevent organic sewage from permeating underground to cause secondary pollution, and taking the treated land as a treatment pool; bricks or stones are built around the treatment tank, the height is 60cm, the high-concentration sewage is prevented from overflowing, and the heavy rain is prevented from overflowing; graded sand stone (evenly mixed stones and broken bricks), local river mud or pond mud and introduction materials are uniformly paved in the treatment tank, the treatment activity of the drooping cymbidium can be quickly started and cultured, the decomposition of microorganisms on organic matters is realized, the absorption of roots of the drooping cymbidium on decomposed substances is realized, and the rapid growth of the drooping cymbidium is promoted.

One end of the treatment tank (ditch) is provided with a header sump for dumping organic wastewater, distributing water and replenishing water; the other end of the treatment tank is provided with a tail water collecting pit, so that the water quality can be observed and monitored conveniently and a circulating water pump can be installed conveniently; an overflow port is arranged at the tail part of the treatment tank, treated water reaching the standard can be naturally discharged or pumped out from the overflow port, and a circulating pump is arranged in a tail water collecting pit and can pump the water in the treatment tank to the head part for circulation. The drogue umbrella grass can be fixedly arranged in the processing pool in a diagonal mode or a parallel mode. Ridge banks (adopting the same graded sand stone, river mud and introduction materials) can be arranged in the pool, drooping cymbidium herbs are planted on the ridges, and sewage can be treated after the drooping cymbidium herbs are rooted.

When organic wastewater is treated, the organic wastewater is firstly drained to the water collecting pit at the head part for storage, so that the organic wastewater is uniformly distributed in the treatment tank and naturally flows towards the tail part under the action of water potential. In order to improve the treatment efficiency of the device, the liquid level in the device needs to be controlled to be less than 5-10 cm away from the surface of a filler in the pot (the root of the drooping bevel grass is not in a full-submerged state). It is emphasized that the adaptation time is required for cultivating the droughhaired bevel herb, and the starting time of 7-10 days is required before the organic wastewater is introduced into the head of the treatment tank, so that the daily treatment capacity reaches the design value (1-1000L/m)²D). The organic wastewater to be treated has wide target, can be biogas slurry obtained after anaerobic fermentation of large-scale farm manure and the like, and can also be raw liquid of pig manure and cow manure, or high-concentration kitchen sewage, percolation water of municipal refuse treatment plants, tail water of large-scale aquaculture and the like. Care must be taken that the initial wastewater COD concentration cannot be too high (above 5000mg/L), needs to be diluted and subjected to acclimatization.

When the cultured drooping bevel grass grows to 1.5-1.6 m, the drooping bevel grass can be mowed; or cradling once every month in the period of 5-10 months every year; and (3) properly reducing the amount of introduced organic wastewater after the drogue pennisetum is cradled for 3-5 days so as to reduce the load. The cut drogue pennywort herb can be used as green feed, green dry feed or silage, enters an animal food chain again, can be bundled to be used as fuel after being dried in the sun, can be woven to be used as a hand product and the like, and can be recycled.

Shading properly in summer to prevent the water temperature from exceeding 30 ℃ for a long time, and preferably 20-30 ℃; when the daily average temperature of the environment is lower than 5 ℃ or the lowest temperature is lower than 0 ℃ in spring, autumn and winter, the device is covered with a plastic film for heat preservation and is prevented from freezing.

The invention has the beneficial effects that:

the method for treating the organic wastewater has the capability of quickly and efficiently directly treating the organic wastewater with higher concentration, and the droguella sinensis has the advantages of high growth speed, large biomass, high conversion efficiency and convenient utilization and is not possessed by other plants.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of the unit area of the array installation of droughtonia indica as described in example 1.

FIG. 2 is a schematic diagram of the unit area of the array installation of the droughtonia umbrellata described in example 2.

Reference numbers in the figures:

1-a water collecting pit; 2-a catchment pit; 3-an overflow port; 4-a circulating pump; 5-culturing the droughtonin.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.

Example 1

The embodiment provides a method for treating organic wastewater, which comprises the following steps:

(1) culturing the drogue et drogue: selecting vigorous droughhaired parasol (plant height 50cm), planting into a permeable gardening pot (with the periphery and bottom perforated and the aperture of 0.8cm) with the depth of 25cm and the diameter of 25cm, filling the pot with graded sand, river mud and introduction materials to 20cm, standing at the edge of a water pool for 7d, keeping the pot moist, and obtaining the cultured droughhaired parasol 5 after the roots of the drohaired parasol grow out from the pot holes;

(2) the array design of the drogue grasses: selecting organic waste water with COD concentration of 100mg/L as treatment object, and using formula S ═ alpha_COD)^1.3The array area S is 1m, as can be seen from/400 and N ═ S · ρ²Culturing 5 pieces of droughhaired-stem-like clover, wherein N is 8-12, and in the embodiment, N is 8;

(3) and (3) installing the drogue grasses in an array: selecting a place which cannot be submerged by rainwater, and calculating the area (1 m) according to the step (2)²) Leveling the land, digging the land to a depth of 30cm, paving an impermeable membrane to prevent the organic sewage from permeating the underground to cause secondary pollution, and taking the treated soil as a treatment pool; bricks or stones are laid around the treatment tank, the height is 60cm, high-concentration sewage is prevented from overflowing, and rainstorm overflow is prevented; uniformly paving the uniformly stirred stones, broken bricks and introduction materials in the treatment tank, so that the treatment activity of the droughhaired seal herbs 5 can be quickly started and cultured, the decomposition of microorganisms on high-concentration wastewater is realized, the decomposed substances are absorbed by the roots of the droughhaired seal herbs, and the quick growth of droughhaired seal herb plants is promoted; a head water collecting pit 1 (a square with the side length of 100cm, which is dug 30cm deeper than the treatment tank) is arranged at one end of the treatment tank, the tank is 20m long (a baffling mode can be adopted when the field is limited), a tail water collecting pit 2 (a square with the side length of 100cm, which is dug 30cm deeper than the treatment area) is arranged at the other end of the treatment tank, and an impermeable film and bricks are paved on the water collecting pit 1 and the water collecting pit 2 in the same way. An overflow port 3 is arranged in the water collecting pit 2, the treated water reaching the standard can be naturally discharged or pumped out, and a circulating pump 4 is arranged at the tail part, so that the water in the treating tank can be pumped to the head part 1 for circulation.The cultured droughhaired parasol grasses 5 are fixedly arranged in the treatment tank in a diagonal line mode;

(4) and (3) organic wastewater treatment: introducing organic wastewater into a head part 1 of a treatment tank, naturally percolating the wastewater to a tail part under water potential pressure, treating while flowing, and finally obtaining standard treatment to reach a water collecting pit 2; if necessary, starting the circulating pump 4 until the treatment is finished and the water is discharged; after treatment, the organic wastewater alpha_CODReducing the concentration to below 50 mg/L;

(5) maintenance: in the treatment process, when the drooping bevel grass 5 to be cultured grows to 1.5m high, the drooping bevel grass is mowed; within 3d after the drooping cymbidium herbs 5 are cultured and mown, the amount of introduced organic wastewater needs to be properly reduced so as to reduce the load; shading properly in summer to prevent the water temperature from exceeding 30 ℃ for a long time; when the daily average temperature of the environment is lower than 5 ℃ in spring, autumn and winter, plastic films are buckled for heat preservation and freezing is prevented.

Example 2

The embodiment provides a method for treating organic wastewater, which comprises the following steps:

(1) culturing the drogue et drogue: selecting vigorous droughhaired parasol grasses (the plant height is 100cm), planting the vigorous droughhaired parasol grasses into a permeable gardening pot (the periphery and the bottom are perforated and the aperture is 1cm) with the depth of 25cm and the diameter of 25cm, filling the pot with graded sandstone, river mud and introduction substances to 20cm, standing the pot in a ditch for 10 days, keeping the pot moist, and obtaining the cultured droughhaired parasol grasses 5 after the roots of the droughhaired parasol grasses grow out from the pot holes;

(2) the array design of the drogue grasses: selecting organic waste water with COD concentration of 100mg/L as treatment object, and using formula S ═ alpha_COD)^1.3The array area S is 1m, as can be seen from/400 and N ═ S · ρ²Culturing 5 pieces of droughhaired-stem-like clover, wherein N is 8-12, and N is 12 in the embodiment;

(3) and (3) installing the drogue grasses in an array: selecting a place which cannot be submerged by rainwater, and calculating the area (1 m) according to the step (2)²) Leveling the land, digging 50cm deep, paving an impermeable membrane to prevent the organic sewage from permeating into the ground to cause secondary pollution, and taking the organic sewage as a treatment pool; bricks or stones are laid around the treatment tank, the height is 60cm, high-concentration sewage is prevented from overflowing, and rainstorm overflow is prevented; uniformly paving uniformly-stirred stones, broken bricks and seeds in the treatment tankThe device can quickly start the treatment activity of the cultured drooping umbrella grass 5, realize the decomposition of microorganisms on high-concentration wastewater, realize the absorption of decomposed substances by the roots of the drooping umbrella grass and promote the quick growth of drooping umbrella grass plants; a head water collecting pit 1 (a square with the side length of 100cm, 50cm deeper than the treatment tank) is arranged at one end of the treatment tank, the tank is 20m long (a baffling mode can be adopted when the field is limited), a tail water collecting pit 2 (a square with the side length of 100cm, 50cm deeper than the treatment area) is arranged at the other end of the treatment tank, and an impermeable film and bricks are laid in the water collecting pit 1 and the water collecting pit 2 in the same way. An overflow port 3 is arranged in the water collecting pit 2, the treated water reaching the standard can be naturally discharged or pumped out, and a circulating pump 4 is arranged at the tail part, so that the water in the treating tank can be pumped to the head part 1 for circulation. The cultured droughhaired parasol grasses 5 are fixedly arranged in the processing pool in a parallel mode;

(4) and (3) organic wastewater treatment: introducing organic wastewater into the head part 1 of the treatment tank, naturally percolating the wastewater to the tail part under the water potential pressure, treating while flowing, and finally obtaining standard treatment to reach a water collecting pit; if necessary, starting the circulating pump 4 until the treatment is finished and the water is discharged; after treatment, the organic wastewater alpha_CODReducing the concentration to below 50 mg/L;

(5) maintenance: in the processing process, the mowing is carried out once every month in the period of 5-10 months every year; after 5d of cultivating the drooping umbellate grasses 5 and cutting, properly reducing the amount of introduced organic wastewater so as to reduce the load; shading properly in summer to prevent the water temperature from exceeding 30 ℃ for a long time; when the daily average temperature of the environment is lower than 0 ℃ in spring, autumn and winter, plastic films are buckled for heat preservation and freezing is prevented.

The invention also provides examples 3-5, which are used for respectively treating organic wastewater with COD concentration of 1000mg/L, 2000mg/L and 5000mg/L, the specific operation steps of the examples 3-5 are the same as those of the example 1, and the array design of the drogue et al of the examples 3-5 is shown in Table 2.

TABLE 2

	Example 3	Example 4	Example 5
				Initial alphaCOD(mg/L)	1000	2000	5000
After treatment alphaCOD(mg/L)	≤50	≤50	≤50
				Environmental conditions	23～25℃	23～25℃	23～25℃
S(m2)	20	49	161
				N (pieces)	160	588	1288

Finally, the inventor further tests, and the results are shown in Table 3, wherein 6kg/d biogas slurry is treated for 30 d. Wherein, the width of the test paradise ditch is 0.25m, the length is 10m, the depth is 0.2m, and the environmental temperature is 20-30 ℃.

TABLE 3

	Before treatment	After treatment	Removal case/removal rate
				Biogas slurry state	Black, thin soup-like	Yellowish	/
pH value of biogas slurry	8.8	7.7	Is in alkalescence
				Biogas slurry alphaCOD(mg/L)	2013	43	97.9％
Biogas slurry TN (%)	0.432	0.007	98.4％
				Biogas slurry TP (mg/kg)	252	2.1	99.2％
Growth of drooping bevel grass	30～40cm	150～180cm	/

Note: removal rate (pre-treatment value-post-treatment value)/pre-treatment value × 100%

In conclusion, the high-efficiency biological method for treating the organic wastewater has obvious effect.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.