On-site sewage and odor treatment equipment in sewage treatment plants

Abstract

The present invention discloses an in-situ sewage and odor treatment device for a sewage treatment plant, which is mainly composed of an odor collection system, an odor delivery system, and an odor treatment system; the odor collection system is composed of an air collecting hood, an air duct, and a first fan; the odor delivery system is composed of a pipeline and a second fan; the odor treatment system uses a partition to separate the anoxic tank, which is divided into a front selection tank area and a rear anoxic tank area, wherein the front selection tank has three different structures, and suitable schemes can be adopted for different situations to dissolve the odor, and then the nitrate-containing sewage and sulfur-containing and ammonia-containing odor are treated in situ through the synchronous denitrification and desulfurization and anaerobic ammonia oxidation reaction mechanism. The scheme of the present invention is simple, low in cost, and novel in concept. While removing the odor of the urban sewage treatment plant, the sulfide and ammonia therein are used to reduce nitrates, thereby meeting the requirements of denitrification in sewage, achieving waste treatment with waste, and reducing the carbon source input and residual sludge output, and having good ecological benefits.

Description

Technical Field

[0001] The invention relates to an in-situ sewage and odor treatment device for a sewage treatment plant, belonging to the technical field of wastewater biological treatment. Background Art

[0002] At present, most of the urban domestic sewage is treated by traditional biological nitrification / denitrification process (A 2 / O, A / O process), while in the denitrification process, an organic carbon source is required as an electron donor to convert NO X - -N is reduced to N2, but the C / N ratio of urban domestic sewage in my country is generally low. The lack of carbon source in domestic sewage leads to low denitrification efficiency and excessive total nitrogen in the effluent, which cannot meet the Class A emission standard of "Pollutant Discharge Standard for Urban Sewage Treatment Plants" (GB18918-2002). After treatment with this process, a large amount of residual sludge will be generated, and the disposal of the residual sludge has gradually become a major problem.

[0003] During the urban sewage treatment process, a large amount of malodorous gases will be released into the external environment, which will cause potential harm to people's living environment and health. At present, occupational diseases are frequent among the workers in urban sewage treatment plants, and there is a lack of relevant standards for gas release in urban sewage treatment plants. Therefore, the release of malodorous gases during sewage treatment has become an urgent problem to be solved. At the same time, studies have shown that the inorganic components in these malodorous gases are mainly volatile substances containing sulfur and nitrogen elements, which are very important for the use of A 2 / O process wastewater and sludge treatment process, the possible sources of gas release were detected and it was found that the screen, lift pump room, primary sedimentation tank, anaerobic zone, anoxic zone, secondary sedimentation tank, sludge thickening tank and sludge dewatering room would produce a large amount of malodorous gases mainly composed of H2S and NH3.

[0004] The simultaneous denitrification and desulfurization process and the anaerobic ammonium oxidation process have been the focus of research on autotrophic denitrification of wastewater in recent years. The simultaneous denitrification and desulfurization process refers to the autotrophic denitrification process in which certain obligate inorganic chemoautotrophic Thiobacillus species use reducing sulfur-containing compounds (such as sulfide, etc.) as electron donors to reduce nitrate nitrogen to N2 in an anaerobic or anoxic environment. The simultaneous denitrification and desulfurization process has the characteristics of no need to add carbon source, carbon footprint consumption, low sludge production, and low energy consumption. Anaerobic ammonium oxidation refers to the production of N2 under anaerobic or anoxic conditions, using ammonium salts as electron donors and nitrite / nitrate as electron acceptors under the action of anaerobic ammonium-oxidizing bacteria; compared with traditional biological denitrification processes, the anaerobic ammonium oxidation process has the advantages of saving energy, no need for external carbon sources, and low sludge production.

[0005] For biological processes using denitrification functions (such as A 2 / O, A / O process) sewage treatment plants, industrial wastewater treatment plants or domestic sewage treatment plants, the present invention utilizes the reducing sulfide and ammonia in the odor as electron donors, through the simultaneous denitrification and desulfurization and anaerobic ammonia oxidation process, without the need for external odor treatment equipment, based on the original anoxic tank for transformation, the nitrate in the sewage and the sulfide and ammonia in the odor can be treated in situ, and the problems of insufficient carbon source, nitrogen pollution and large sludge production in the sewage treatment process can be solved, and the present invention has broad application prospects and ecological benefits. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies of the prior art and provide an in-situ sewage and odor treatment device for a sewage treatment plant.

[0007] The object of the present invention is achieved through the following technical solutions: an in-situ sewage and odor treatment device for a sewage treatment plant, the device mainly consists of an odor collection system, an odor delivery system, and an odor treatment system;

[0008] The odor collection system is composed of an air collection hood, an air duct, and a first fan; the air collection hood is used to collect odor in the sewage treatment plant and transport it to the odor transport system through the air duct, and the first fan is connected to the air duct to extract the odor from the air collection hood;

[0009] The odor transport system is composed of a pipeline and a second fan; the pipeline is connected to the air duct in the odor collection system to transport the odor to the odor treatment system, and the second fan is connected to the pipeline to extract the odor in the pipeline;

[0010] The odor treatment system is obtained by in-situ transformation of the anoxic tank. The anoxic tank is separated by a partition to form a front selection tank area and a rear anoxic tank area. The partition is a perforated plate with an overflow port on the upper part of the partition. The front selection tank can be transformed in three ways, namely:

[0011] a. The front selection pool consists of three parts: a water pump, a circulation pipeline, and a pool body. The pool body is divided into an air distribution layer, an aeration layer, a filler layer, and a spray layer from bottom to top. The air distribution layer has a gas inlet, and the spray layer has a water inlet and a spray device. The gas inlet of the air distribution layer is connected to the pipeline in the odor delivery system to transport the odor to the front selection pool. The circulation pipeline connects the water inlet of the front selection pool and the water outlet of the rear anoxic pool through a water pump to circulate water in the anoxic pool. Modification method a is suitable for the case where water needs to flow continuously through the filler and the H2S in the odor to be treated is ≥500g / m 3 ;

[0012] b. The front selection tank consists of three parts: a humidifier, a circulation pipeline, a water pump, and a tank body. The tank body is divided into an air distribution layer, an aeration layer, and a packing layer from bottom to top, and there is a water inlet on the top of the tank body; the humidifier is connected to the pipeline in the odor transport system to humidify the odor, and the air distribution layer has a gas inlet connected to the humidifier to transport the moistened odor to the front selection tank; the circulation pipeline connects the humidifier of the front selection tank and the water outlet of the rear anoxic tank through a water pump to humidify the odor; modification method b is suitable for the mass concentration of organic matter in the intake air is 600-5000mg / m 3 The amount of odor to be treated ranges from 1000 to 150000m 3 / h;

[0013] c. The front selection pool is composed of three parts: a water pump, a circulation pipeline, and a pool body. The pool body is divided into an air distribution layer and an aeration layer from bottom to top, and a water inlet is set on the top of the pool body. The circulation pipeline connects the water inlet of the front selection pool and the water outlet of the rear anoxic pool through a water pump to circulate water in the anoxic pool. Modification method c is suitable for odor transport speeds of 20m 3 / (m 2 . h) the following;

[0014] In the three schemes a, b and c, the water from the front selection tank flows into the rear anoxic tank through the baffle. When the water level is too high, it can flow into the rear anoxic tank through the overflow port. No changes are made to the equipment in the rear anoxic tank area, and enriched microorganisms with simultaneous denitrification, desulfurization and anaerobic ammonia oxidation functions are added to the anoxic tank.

[0015] Furthermore, the air collecting hood is made of stainless steel frame + solar panel or stainless steel frame + fiberglass panel, and the air collecting method is suction type or blowing-suction type; the air duct adopts dry pipe configuration, the branch pipe wind speed is ≤6m / s, and the main pipe wind speed is ≤12m / s.

[0016] Furthermore, the partition is placed at 1 / 10-1 / 3 of the entire anoxic pool near the water inlet side, the partition is set 5-10 cm lower than the front selection pool water inlet and the rear anoxic pool outlet, and the width is the same as the anoxic pool.

[0017] Furthermore, the height of the aeration layer in the front selection pool is 0.2-0.8m higher than the pool bottom, and the aeration volume of the aeration layer is determined according to the odor air volume.

[0018] For transformation method a, the velocity of odor in the aeration layer is 1.5-6m / s, and the residence time is between 20-30s.

[0019] For transformation method b, the velocity of odor in the aeration layer is 0.3-1.5m / s, the pressure drop is 0.15-0.6kPa / m filler, and the liquid-gas ratio is 0.5-2.0kg / kg.

[0020] For transformation method c, the rate of odor in the aeration layer is 1-2.5m / s, and the liquid flow rate is calculated based on the cross section of the aeration layer to be 1.5-3.8m 3 / (m 2 . h).

[0021] Furthermore, the filler layer in the front selection tank has a specific surface area of ​​1-100cm 2 / g, 60% of the filler particles in the packing layer have a diameter greater than 4mm, and the filling height of all fillers in the packing layer is 0.5-2m.

[0022] Furthermore, the water inflow of the spray layer of the front selection pool is 1 / 4-1 / 3 of the odor air volume, and the spray intensity is 10m 3 / (m 2 . h) or above.

[0023] Furthermore, the amount of reflux water in the circulation pipeline of the front selection tank is 10%-40% of the amount of inlet water.

[0024] Furthermore, the sludge concentration of the post-anoxic tank MLSS is 3000-5000 mg / L, the pH is controlled at 6.5-7.5, the dissolved oxygen is ≤0.5 mg / L, and the HRT is 2.5-10h.

[0025] Furthermore, the added microorganisms having simultaneous denitrification and desulfurization and anaerobic ammonium oxidation functions after enrichment are obtained by respectively adding sludge having simultaneous denitrification and desulfurization functions [VSS is 10-15 g / L, and the specific sludge activity is 0.8-1.5 g TS / (gVSS·d)] and sludge having anaerobic ammonium oxidation functions [VSS is 10-15 g / L, and the specific sludge activity is 1.2-1.9 g TN / (gVSS·d)] to the anoxic tank sludge, and the addition ratios (volume ratios) of the two sludges are 2.4-5.2% and 2-4%, respectively.

[0026] The present invention has the beneficial effects:

[0027] 1. No need to build external odor treatment equipment, the sewage and odor in the sewage treatment plant can be treated in situ.

[0028] 2. Solve the problem of insufficient carbon source in the process of biological denitrification of sewage.

[0029] 3. Reduce the generation of sludge and the cost of sludge treatment and disposal. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the anoxic pool transformation scheme a of the present invention;

[0031] Figure 2 This is a schematic diagram of the anoxic pool transformation scheme b of the present invention;

[0032] Figure 3 It is a schematic diagram of the anoxic pool transformation scheme c of the present invention;

[0033] Figure 4 It is a bar graph of the removal rates of nitrate, sulfide and ammonia nitrogen at different nitrate concentrations;

[0034] Figure 5 It is a bar graph of the removal rates of nitrate, sulfide and ammonia nitrogen during long-term operation.

[0035] Among them: 1. Odor inlet; 2. Fan; 3. Air distribution layer; 4. Aeration layer; 5. Filling layer; 6. Selection tank; 7. Spray layer; 8. Water inlet; 9. Purified gas outlet; 10. Partition; 11. Overflow port; 12. Agitator; 13. Water outlet; 14. Circulating water flow meter; 15. Water pump; 16. Anoxic tank; 17. Humidifier drain outlet; 18. Humidifier. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] An in-situ sewage and odor treatment device for a sewage treatment plant, the device mainly comprises an odor collection system, an odor transport system, and an odor treatment system;

[0038] The odor collection system consists of an air collecting hood, an air duct, and a first fan; the air collecting hood is used to collect odor in the sewage treatment plant and transport it to the odor transport system through the air duct, and the first fan is connected to the air duct to extract the odor from the air collecting hood; the air collecting hood is made of a stainless steel frame + a polycarbonate plate or a stainless steel frame + a fiberglass plate, and the air collection method is suction or blowing and suction; the air duct adopts a dry pipe configuration method, the branch pipe wind speed is ≤6m / s, and the main pipe wind speed is ≤12m / s.

[0039] The odor transport system is composed of a pipeline and a second fan; the pipeline is connected to the air duct in the odor collection system to transport the odor to the odor treatment system, and the second fan is connected to the pipeline to extract the odor in the pipeline;

[0040] The odor treatment system is obtained by in-situ transformation of the anoxic tank. The anoxic tank is separated by a partition, which is divided into a front selection tank area and a rear anoxic tank area. The partition is a perforated plate with an overflow port on the upper part of the partition. The partition is placed at 1 / 10-1 / 3 of the entire anoxic tank near the water inlet. The height of the partition is 5-10 cm lower than the front selection tank inlet and the rear anoxic tank outlet, and the width is the same as the width of the anoxic tank. The height of the air distribution layer in the front selection tank is 0.2-0.8 m higher than the bottom of the tank, and the aeration volume of the aeration layer is determined according to the odor air volume. The filler layer in the front selection tank is selected with a specific surface area of ​​1-100 cm 2 / g, 60% of the filler particles in the packing layer are larger than 4mm in diameter, and the filling height of all fillers in the packing layer is 0.5-2m. The water inflow of the spray layer of the front selection pool is 1 / 4-1 / 3 of the odor air volume, and the spray intensity is 10m 3 / (m 2 . h) or more. The return water volume in the circulation pipeline of the front selection tank is 10%-40% of the inlet water volume. The front selection tank can be transformed in three ways, namely:

[0041] like Figure 1 As shown, the in-situ sewage and odor treatment device of the sewage treatment plant provided by the present invention is a reconstruction scheme a for the in-situ reconstruction of the anoxic tank part. The anoxic tank after the reconstruction is divided into a selection tank 6 and anoxic tank 16 from left to right. The selection tank 6 and the anoxic tank 16 are separated by a partition 10. The odor first enters the fan 2 through the odor inlet 1, passes into the air distribution layer 3 through the fan, and then is exposed to the tank body through the aeration head of the aeration layer 4. The sewage in the anaerobic tank flows into the spray layer through the water inlet 8, and water is distributed into the tank body by the spray head. When the moist odor passes through the packing layer, H2S and NH3 in the odor are fully dissolved in water, so as to achieve the purpose of purifying the gas. The purified gas is discharged through the gas discharge port 9. The water in the selection tank 6 flows into the anoxic tank through the partition 10. In the oxygen tank 16, the water circulating back from the aerobic tank is fully mixed under the action of the agitator 12, and the enriched microorganisms (sludge) with the functions of simultaneous denitrification, desulfurization and anaerobic ammonia oxidation are added to the anoxic tank. Under the action of the simultaneous denitrification and desulfurization sludge and anaerobic ammonia oxidation bacteria in the anoxic tank 16, simultaneous denitrification, desulfurization and anaerobic ammonia oxidation reactions are carried out in situ, sulfide reacts with nitrite / nitrate to be oxidized into sulfate or elemental sulfur, and ammonia nitrogen reacts with nitrite / nitrate to generate N2. The sewage after the reaction flows into the aerobic tank through the outlet 13, and a certain proportion of the effluent is refluxed at the same time. The reflux flow is controlled by the flow meter 14, and a part of the effluent is refluxed to the water inlet 8 by the water pump 15 for further treatment. Modification method a is suitable for the case where water needs to flow continuously through the filler and the odor to be treated contains H2S ≥ 500g / m 3For transformation method a, the velocity of odor in the aeration layer is 1.5-6m / s, and the residence time is between 20-30s.

[0042] like Figure 2 As shown, the in-situ sewage and odor treatment device of the sewage treatment plant provided by the present invention is a modification scheme b for the in-situ reconstruction of the anoxic tank part. The anoxic tank after the modification is divided into a selection tank 6 and anoxic tank 16 from left to right. The selection tank 6 and the anoxic tank 16 are separated by a partition 10. The odor first enters the fan 2 through the odor inlet 1, and then passes into the humidifier 18 through the fan. In the humidifier, the water refluxed through the water outlet 13 moistens the odor to remove particulate matter and increase humidity, and then passes into the air distribution layer 3, and is exposed to the tank body through the aeration head of the aeration layer 4. When the moist odor passes through the packing layer 5, the H2S and NH3 in the odor are fully dissolved in water, so as to purify the gas. Purpose: The purified gas is discharged through the gas outlet 9, and the water in the selection pool 6 flows into the anoxic pool 16 through the partition 10, and is fully mixed with the water circulated back from the aerobic pool under the action of the agitator 12. The enriched microorganisms (sludge) with the functions of simultaneous denitrification, desulfurization and anaerobic ammonia oxidation are added to the anoxic pool. Under the action of the simultaneous denitrification and desulfurization sludge and anaerobic ammonia oxidation bacteria in the anoxic pool 16, simultaneous denitrification, desulfurization and anaerobic ammonia oxidation reactions are carried out in situ, and sulfide reacts with nitrite / nitrate to be oxidized into sulfate or elemental sulfur, while ammonia nitrogen reacts with nitrite / nitrate to generate N2. The reacted water flows into the aerobic pool through the outlet 13. Transformation method b is suitable for the mass concentration of organic matter in the intake air is 600-5000mg / m 3 The amount of odor to be treated ranges from 1000 to 150000m 3 / h. For transformation method b, the rate of odor in the aeration layer is 0.3-1.5m / s, the pressure drop is 0.15-0.6kPa / m filler, and the liquid-gas ratio is 0.5-2.0kg / kg.

[0043] like Figure 3As shown, the in-situ sewage and odor treatment device of the sewage treatment plant provided by the present invention is a reconstruction scheme c in which the anoxic tank is partially rebuilt in situ. The anoxic tank after the reconstruction is divided into a selection tank 6 and an anoxic tank 16 from left to right. The selection tank 6 and the anoxic tank 16 are separated by a partition 10. The sewage in the anaerobic tank flows into the selection tank through the water inlet 8, and the odor enters the fan 2 through the odor inlet 1, passes into the air distribution layer 3 through the fan, and then is exposed to the tank body through the aeration head of the aeration layer 4. The exposed gas is directly dispersed into the mixed liquid flowing into the anaerobic tank, and the purified gas is discharged through the gas exhaust port 9. The water in the selection tank flows into the anoxic tank 16 through the partition 10 and is circulated back and forth with the water in the aerobic tank. The incoming water is fully mixed under the action of the agitator 12, and the enriched microorganisms (sludge) with the functions of simultaneous denitrification, desulfurization and anaerobic ammonia oxidation are added to the anoxic tank. Under the action of the simultaneous denitrification and desulfurization sludge and anaerobic ammonia oxidation bacteria in the anoxic tank 16, simultaneous denitrification, desulfurization and anaerobic ammonia oxidation reactions are carried out in situ. Sulfide reacts with nitrite / nitrate to oxidize into sulfate or elemental sulfur, and ammonia nitrogen reacts with nitrite / nitrate to generate N2. The reacted water flows into the aerobic tank through the outlet 11, and a certain proportion of the effluent is refluxed at the same time. The reflux flow is controlled by the flow meter 14, and a part of the effluent is refluxed to the water inlet 8 by the water pump 15 for further treatment. Modification method c is suitable for the odor transport speed of 20m 3 / (m 2 . h) or less. For transformation method c, the rate of odor in the aeration layer is 1-2.5m / s, and the liquid flow rate is calculated based on the cross section of the aeration layer to be 1.5-3.8m 3 / (m 2 . h).

[0044] The added microorganisms with simultaneous denitrification and desulfurization and anaerobic ammonium oxidation functions after enrichment are obtained by respectively adding sludge with simultaneous denitrification and desulfurization functions [VSS is 10-15 g / L, and the specific sludge activity is 0.8-1.5 gTS / (gVSS·d)] and sludge with anaerobic ammonium oxidation functions [VSS is 10-15 g / L, and the specific sludge activity is 1.2-1.9 gTN / (gVSS·d)] to the anoxic tank sludge, and the addition ratios (volume ratio) of the two sludges are 2.4-5.2% and 2-4%, respectively.

[0045] The sludge concentration of the post-anaerobic tank is MLSS 3000-5000 mg / L, the pH is controlled at 6.5-7.5, the dissolved oxygen is ≤0.5 mg / L, and the HRT is 2.5-10h.

[0046] Example 1

[0047] The laboratory simulated the treatment of sewage and odor in the sewage treatment plant, that is, the odor in the sewage treatment plant was dissolved in the nitrate-containing sewage to examine the removal performance of sulfide, nitrate and ammonia nitrogen in the sewage. The sulfide concentration range tested in this experiment was 60mg / L-540mg / L, the nitrate concentration range was 10.5mg / L-94.5mg / L, and the ammonia nitrogen concentration range was 70-80mg / L.

[0048] When the concentrations of sulfide, nitrate and ammonia nitrogen in the influent were 60 mg / L, 10.5 mg / L and 70.9 mg / L respectively, the removal rates of sulfide, nitrate and ammonia nitrogen were 94%, 90% and 13% respectively. As the influent matrix concentration increased further, the removal rates of sulfide, nitrate and ammonia nitrogen remained above 90%, 89% and 21% respectively.

[0049] After many experiments, the average removal rate of sulfide in each group was 97%, the average removal rate of nitrate was 94%, and the average removal rate of ammonia nitrogen was 32%. The removal effect was good and relatively stable. Figure 4 shown.

[0050] This implementation case uses the activated sludge method, the pH value is controlled at 7.0±0.1, and the temperature is controlled at 25-35℃.

[0051] Example 2

[0052] Through the laboratory simulation experiment of sewage treatment plant sewage and odor treatment, that is, simulating the odor in the sewage treatment plant dissolved in nitrate-containing sewage, the removal performance of sulfide, nitrate and ammonia nitrogen in the sewage was examined. This experiment tested the long-term removal performance of the treatment device for sulfide, nitrate and ammonia nitrogen when the influent sulfide concentration was 60mg / L, the nitrate concentration was 10.5mg / L, and the ammonia nitrogen concentration ranged from 72-78mg / L.

[0053] When the influent sulfide concentration is low, the effluent sulfide removal efficiency is stable at more than 90% for many days, and the average removal rate is 94%; the nitrate removal rate is stable at more than 88% for many days, and the average removal rate is 90%; at the same time, it also has a certain removal effect on ammonia nitrogen, and the average ammonia nitrogen removal rate is 14%. The experimental results show that when the in-situ sewage and odor treatment device is operated at a low concentration close to the actual project, the removal effect is good and relatively stable. The experimental results are as follows Figure 5 shown.

[0054] This implementation case uses the activated sludge method, the pH value is controlled at 7.0±0.1, and the temperature is controlled at 25-35℃.

[0055] By conducting simulation experiments on sewage and odor treatment in sewage treatment plants in the laboratory, the experimental results show that the removal effect of sulfide and nitrate in sewage is good, whether in the case of high concentrations of influent sulfide and nitrate, or in the case of low concentrations of influent sulfide and nitrate close to actual engineering. At the same time, there is also a certain removal effect on ammonia nitrogen, indicating that the in-situ sewage and odor treatment equipment of sewage treatment plants can achieve the simultaneous treatment of nitrate-containing sewage and sulfur- and ammonia-containing odor.

[0056] The above embodiments are used to illustrate the present invention rather than to limit the present invention. Any modification and change made to the present invention within the spirit of the present invention and the protection scope of the claims shall fall within the protection scope of the present invention.

Claims

1. An in-situ sewage and odor treatment device in a sewage treatment plant, characterized in that: The device is mainly composed of an odor collection system, an odor delivery system, and an odor treatment system; The odor collection system is composed of an air collection hood, an air duct, and a first fan; the air collection hood is used to collect odor in the sewage treatment plant and transport it to the odor transportation system through the air duct, and the first fan is connected to the air duct to extract the odor from the air collection hood; the air collection hood is made of a stainless steel frame + a sun panel or a stainless steel frame + a fiberglass plate, and the air collection method is suction or blowing and suction; the air duct adopts a dry pipe configuration method, the branch pipe wind speed is ≤6m / s, and the main pipe wind speed is ≤12m / s; The odor transport system is composed of a pipeline and a second fan; the pipeline is connected to the air duct in the odor collection system to transport the odor to the odor treatment system, and the second fan is connected to the pipeline to extract the odor in the pipeline; The odor treatment system is obtained by in-situ transformation of the anoxic pool. The anoxic pool is separated by a partition, and is divided into a front selection pool area and a rear anoxic pool area. The partition is placed at 1 / 10-1 / 3 of the entire anoxic pool near the water inlet. The height of the partition is 5-10 cm lower than the water inlet of the front selection pool and the water outlet of the rear anoxic pool, and the width is the same as the width of the anoxic pool; the height of the air distribution layer in the front selection pool is 0.2-0.8 m higher than the pool bottom, and the aeration volume of the aeration layer is determined according to the odor air volume; the partition is a perforated plate, and an overflow port is provided on the upper part of the partition. There are three transformation methods for the front selection pool, namely: a. Applicable to the case where water needs to flow continuously through the packing and the H2S in the odor to be treated is ≥500g / m 3 :The front selection pool is composed of three parts: a water pump, a circulation pipeline, and a pool body. The pool body is divided into an air distribution layer, an aeration layer, a filler layer, and a spray layer from bottom to top. The air distribution layer has a gas inlet, and the spray layer has a water inlet and a spray device; the gas inlet of the air distribution layer is connected to the pipeline in the odor delivery system to transport the odor to the front selection pool; the rate of the odor in the aeration layer is 1.5-6m / s, and the residence time is between 20-30s; the circulation pipeline connects the water inlet of the front selection pool and the water outlet of the rear anoxic pool through a water pump to circulate water in the anoxic pool; b. Applicable to the mass concentration of organic matter in the inlet air between 600-5000mg / m 3 The amount of odor to be treated ranges from 1000 to 150000m 3 / h: The front selection tank is composed of a humidifier, a circulation pipeline, a water pump and a tank body. The tank body is divided into an air distribution layer, an aeration layer and a filler layer from bottom to top, and a water inlet is provided on the top of the tank body; the humidifier is connected to the pipeline in the odor transport system to humidify the odor, and the air distribution layer has a gas inlet connected to the humidifier to transport the moistened odor to the front selection tank; the rate of the odor in the aeration layer is 0.3-1.5m / s, the pressure drop is 0.15-0.6kPa / m filler, and the liquid-gas ratio is 0.5-2.0kg / kg; the circulation pipeline connects the humidifier of the front selection tank and the water outlet of the rear anoxic tank through a water pump to humidify the odor; c. Applicable to the odor conveying speed of 20m 3 / (m 2 . h) Below: The front selection pool consists of three parts: water pump, circulation pipeline and pool body. The pool body is divided into air distribution layer and aeration layer from bottom to top. The water inlet is set at the top of the pool body. The rate of odor in the aeration layer is 1-2.5m / s, and the liquid flow rate is calculated according to the cross section of the aeration layer to be 1.5-3.8m 3 / (m 2 . h); the circulation pipeline connects the water inlet of the front selection pool and the water outlet of the rear anoxic pool through a water pump to circulate water in the anoxic pool; The filler layer in the front selection tank has a specific surface area of ​​1-100 cm 2 / g, 60% of the filler particles in the packing layer have a diameter greater than 4mm, and the filling height of all fillers in the packing layer is 0.5-2m; the water inflow of the spray layer of the front selection pool is 1 / 4-1 / 3 of the odor air volume, and the spray intensity is 10m 3 / (m 2 . h) or above; the amount of return water in the circulation pipeline of the front selection tank is 10%-40% of the inlet water amount; in the three schemes a, b and c, the water of the front selection tank flows into the rear anoxic tank through the baffle, and when the water level is too high, it can flow into the rear anoxic tank through the overflow port; the device of the rear anoxic tank area is not changed, and enriched microorganisms with synchronous denitrification and desulfurization and anaerobic ammonia oxidation functions are added to the anoxic tank; the sludge concentration of the rear anoxic tank MLSS is 3000-5000 mg / L, the pH is controlled at 6.5-7.5, the dissolved oxygen is ≤0.5 mg / L, and the HRT is 2.5-10h; the added enriched microorganisms with synchronous denitrification and desulfurization and anaerobic ammonia oxidation functions are obtained by adding sludge with synchronous denitrification and desulfurization functions and sludge with anaerobic ammonia oxidation functions to the anoxic tank sludge, and the volume ratios of the two sludges are 2.4-5.2% and 2-4% respectively.

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