A method for efficient startup and activity recovery of nitritation of ammonia nitrogen wastewater based on zeolite adsorption-aerobic biological regeneration

Abstract

The present invention discloses a method for efficient startup and activity recovery of nitrosation of ammonia nitrogen wastewater based on zeolite adsorption-aerobic biological regeneration. When nitrosation of ammonia nitrogen wastewater is carried out by zeolite adsorption-aerobic biological regeneration, ammonia nitrogen wastewater containing calcium and magnesium ions enters the zeolite filter column for a long time, and the filter material thereof will be compacted. At the same time, calcium carbonate scale and the like will be generated inside to block the pores of the filter material, affecting the overall adsorption-regeneration nitrosation effect. The ammonia nitrogen nitrosation conversion rate will drop by more than 80%. The filter column is pickled and soaked with a dilute acid solution, and the pickling pH value is controlled to be 2 to 5, and the soaking time is 1 to 6 hours. After pickling, the pickling liquid is discharged, and the adsorption-aerobic biological regeneration nitrosation effect of the zeolite filter column is rapidly restored, solving the scaling and clogging problem of the zeolite packing column. At the same time, the activity of AOB is recovered faster, making it less affected by pickling, while NOB is eliminated by pickling, and the NAR quickly reaches more than 90%. This method is also suitable for rapid startup of the reactor to wash NOB.

Description

Technical Field

[0001] The present invention belongs to the technical field of environmental engineering wastewater treatment and discloses a method for efficiently starting and restoring the activity of nitrosation of ammonia nitrogen wastewater based on zeolite adsorption-aerobic biological regeneration. Specifically, it relates to a method for restoring the effect of a biofilm method using a zeolite filter column for a long time. The zeolite filter is acid-washed with a dilute acid solution to achieve stable nitrosation of the ammonia nitrogen wastewater. Background Art

[0002] Ammonia nitrogen is one of the main pollutants in water pollution, and the deteriorating water environment and water quality are not optimistic. Intensifying water pollution prevention and control efforts and further developing and applying more advanced wastewater treatment technologies are urgent needs in the water treatment sector.

[0003] Compared to traditional biological denitrification technologies, anaerobic ammonium oxidation (ANAMMOX) technology can save 60% of aeration energy and avoid the use of carbon sources for denitrification, making it a recognized low-carbon, energy-saving biological denitrification technology. This technology relies on the stable nitritation of ammonia-nitrogen wastewater and requires a stable nitrite-to-ammonia nitrogen ratio in the influent at around 1.32. Therefore, to support subsequent ANAMMOX treatment, a nitritation solution is required for subsequent treatment steps.

[0004] Adsorption is a common physicochemical treatment method for ammonia-nitrogen wastewater. It removes ammonia-nitrogen from wastewater by exchanging ions between ammonia-nitrogen adsorbent materials and ammonium ions in water. After adsorption, the adsorbent must be regenerated, either through chemical desorption or biochemical regeneration, to release the adsorbed ammonia-nitrogen and enable its recycling. A report has proposed a method for treating low-concentration ammonia-nitrogen wastewater by combining adsorption with anaerobic ammonium oxidation (Application No. 201711478996.7). In this method, low-concentration ammonia-nitrogen wastewater first undergoes adsorption treatment, achieving Class A discharge standards for ammonia-nitrogen in the effluent. During the desorption and regeneration process, both biological and chemical desorption processes are completed in the same reactor, yielding a regeneration solution containing both nitrite and ammonia-nitrogen. Finally, the regeneration solution undergoes anaerobic ammonium oxidation treatment, achieving low-carbon denitrification. This method has achieved initial success in the laboratory, but numerous challenges have arisen during engineering trials. First, a large amount of filter media is required in the project, and the accumulation of filter media will affect the water distribution effect, resulting in saturated adsorption of some filter media while the adsorption of other filter media has not reached the limit; second, the pH of ammonia nitrogen wastewater will not be ideal. Wastewater usually contains more calcium and magnesium ions. If such wastewater is passed for a long time, calcium and magnesium ions will react with alkalinity to produce calcium carbonate and magnesium bicarbonate scale, which will affect the filter media's adsorption of ammonia nitrogen; third, long-term passage of such wastewater will produce scale, the pore surface of the filter media will be blocked, the biofilm attachment effect will deteriorate, and the maximum efficiency of biosorption cannot be exerted, thereby reducing the nitrite concentration in the biosorption effluent, which is not conducive to the continuous and stable operation of the reactor. Summary of the Invention

[0005] In order to solve the related problems, the purpose of the present invention is to provide a method for efficient startup and activity recovery of nitritation of ammonia nitrogen wastewater based on zeolite adsorption-aerobic biological regeneration.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A method for efficient startup and activity recovery of nitritation of ammonia nitrogen wastewater based on zeolite adsorption-aerobic biological regeneration, comprising the following steps:

[0008] S1. Treat ammonia nitrogen wastewater using an adsorption-aerobic biological regeneration method, select zeolite as the adsorption-aerobic biological regeneration filter material, use a diluted acid solution to clean the adsorption-regeneration filter material column, and control the pH value to 2-5 without filtering the filter material. The soaking time is 1-6 hours; start the circulating aeration at an aeration frequency of 20-50 Hz; discharge the acid wash solution, and start the nitrosation effect of the adsorption-regeneration filter material column;

[0009] S2. Ammonia nitrogen wastewater is introduced into the adsorption-regeneration filter column. As adsorption proceeds, when the ammonia nitrogen concentration in the effluent reaches the ammonia nitrogen concentration limit specified in the sewage discharge standard, water inlet is stopped. After water inlet is stopped, aeration is introduced into the adsorption-regeneration filter column to perform internal circulation aerobic aeration biodesorption. At the same time, alkalinity is added to cause a nitrification reaction to convert ammonia nitrogen into nitrite. The obtained nitrite wastewater is supplied to the short-cut nitrification, denitrification, and anaerobic ammonium oxidation sections.

[0010] S3, repeat step S2, when the filter material is found to be caking, the ammonia nitrogen concentration in the effluent is higher than the ammonia nitrogen concentration limit in the sewage discharge standard, and the converted nitrite concentration is lower than the average value, use dilute acid to clean the adsorption-regeneration filter material column, the dilute acid does not filter the filter material, control the pH value to be 2-5, and soak for 1-6 hours; start the circulation aeration, the aeration frequency is 20-50Hz; discharge the acid wash liquid, the adsorption-regeneration filter material column adsorption-regeneration nitrosation effect is restored, and then continue to repeat step S2. The reason for the decrease in the nitrosation conversion rate of ammonia nitrogen is that the ammonia nitrogen wastewater introduced usually contains a large amount of calcium and magnesium ions. If such wastewater is introduced for a long time, the calcium and magnesium ions react with the alkalinity to produce calcium carbonate and magnesium bicarbonate scale, the filter material will become caking, and it is impossible to evenly distribute water, and its adsorption effect will be greatly reduced. At the same time, calcium carbonate scale and the like are generated inside to block the pores of the filter material, affecting the overall adsorption-regeneration nitrosation effect, and its ammonia nitrogen conversion effect also deteriorates sharply, and the nitrosation conversion rate of ammonia nitrogen will decrease by more than 80%.

[0011] Furthermore, the acid solution in steps S1 and S3 is any one or more of hydrochloric acid, sulfamic acid, and citric acid.

[0012] Furthermore, the zeolite in steps S1 and S3 is a natural zeolite or an artificial zeolite having the ability to adsorb ammonia nitrogen.

[0013] Furthermore, the zeolite in steps S1 and S3 is 40±10 mesh.

[0014] Furthermore, the ammonia nitrogen concentration of the ammonia nitrogen wastewater described in step S2 is 90-120 mg / L, the nitrate nitrogen concentration of the inlet is 40-60 mg / L, and the pH is 8.5-9.5.

[0015] Furthermore, the alkalinity in step S2 is any one of sodium carbonate, sodium hydroxide, and potassium hydroxide, and the dosage is 0.6 to 1 g / L.

[0016] Furthermore, the aeration conditions in step S2 are: dissolved oxygen concentration 5.0±1 mg / L, and time 12±4 h.

[0017] Furthermore, after adding alkalinity in step S2, the pH is adjusted to 8.5-9.5.

[0018] Furthermore, the ammonia nitrogen concentration of the ammonia nitrogen wastewater described in step S2 is 90-120 mg / L, the nitrate nitrogen concentration of the inlet is 40-60 mg / L, and the pH is 8.5-9.5.

[0019] An adsorption-regeneration ammonia nitrogen wastewater nitrification device, the device comprising an ammonia nitrogen wastewater inlet pool 1, an adsorption-regeneration filter material reactor 4, an adsorption outlet pool 7, a nitrification liquid storage pool 8, an alkali solution dosing tank 12, and a dilute acid solution dosing tank 15;

[0020] The ammonia nitrogen wastewater inlet pool 1 enters the adsorption-regeneration filter material reactor 4 through the water inlet pump 2. The adsorption-regeneration filter material column reactor 4 is provided with a water inlet and a water outlet. The water inlet is fed with actual ammonia nitrogen wastewater. The connected pipeline is provided with a water inlet pump 2 and a water inlet valve 3. The adsorption effluent is discharged into the adsorption effluent pool 7, and the desorption effluent is discharged into the nitrite liquid storage tank 8.

[0021] The adsorption water outlet pool 7 pipeline is provided with a water outlet valve 6;

[0022] The nitrite liquid storage tank 8 is provided with a desorption water outlet valve 9;

[0023] The adsorption-regeneration filter column reactor 4 is filled with zeolite 5, and the bottom is connected to an aeration fan 11. The alkalinity dosing tank 12 and the diluted acid dosing tank 15 are connected to the adsorption-regeneration filter column reactor 4 through pipes.

[0024] The aeration blower 11 is connected to the adsorption-regeneration filter column reactor 4 through a pipeline, and an aeration valve 10 is provided on the pipeline.

[0025] The alkalinity dosing tank 12 is connected to the adsorption-regeneration filter column reactor 4 through a pipeline, and the alkali solution is pumped into the adsorption-regeneration filter column reactor 4 through a dosing pump 13, and a dosing valve 14 is provided for regulation;

[0026] The dilute acid solution adding barrel 15 is connected to the adsorption-regeneration filter column reactor 4 through a pipeline for adding the dilute acid solution.

[0027] The method for using the above-mentioned adsorption-regeneration ammonia nitrogen wastewater nitrification device comprises the following steps:

[0028] (1) Adding diluted acid to the diluted acid dosing tank 15, using the diluted acid to clean the filter material in the adsorption-regeneration filter column reactor 4, the diluted acid does not filter the filter material, controlling the pH value to 2-5, and soaking for 1-6 hours; starting the circulating aeration, the aeration frequency is 20-50 Hz; discharging the acid wash solution, and starting the nitrosation effect of the adsorption-regeneration filter column;

[0029] (2) Operate the equipment according to the adsorption-aerobic biological regeneration method; when the filter media agglomerates, the ammonia nitrogen concentration in the effluent is higher than the ammonia nitrogen concentration limit in the sewage discharge standard, and the converted nitrite concentration is lower than the average value, stop the operation, add diluted acid to the diluted acid dosing tank 15, and use the diluted acid to clean the filter media in the adsorption-regeneration filter media column reactor 4. The diluted acid does not filter the filter media, and the pH value is controlled to be 2-5, and the soaking time is 1-6 hours; start the circulating aeration, and the aeration frequency is 20-50Hz; discharge the acid wash liquid, and the nitrification effect of the adsorption-regeneration filter media column is restored, and then continue to operate the equipment according to the adsorption-aerobic biological regeneration method.

[0030] Furthermore, the equipment is operated according to the adsorption-aerobic biological regeneration method, which means that the ammonia nitrogen wastewater in the ammonia nitrogen wastewater inlet pool 1 is continuously pumped into the adsorption-regeneration filter column reactor 4 through the water inlet pump 2. As the adsorption proceeds, the effluent is discharged into the adsorption effluent pool 7. The ammonia nitrogen concentration in the effluent will gradually increase. When the ammonia nitrogen concentration in the effluent reaches the ammonia nitrogen concentration limit in the sewage discharge standard, the water inlet is stopped, and the water inlet valve 3 and the water outlet valve 6 are closed. After the water inlet is stopped, the aeration fan 11 is turned on to introduce aeration into the adsorption-regeneration filter column reactor 4 to carry out internal circulation aeration and biological desorption. Alkalinity is added during aeration at the same time. The alkali solution in the alkalinity dosing tank 12 is pumped into the adsorption-regeneration filter column reactor 4 through the dosing pump 13. A nitrosation reaction occurs to convert ammonia nitrogen into nitrite. When the nitrite concentration of the desorbed water reaches a preset value, the dosing pump 13 is turned off, the dosing valve 14 is closed, the desorption outlet valve 9 is opened, and the desorbed water flows into the nitrite liquid storage tank 8 to obtain nitrite wastewater.

[0031] The principle of this invention is that the stable nitrification of ammonia nitrogen is a key process in the short-range nitrification and denitrification, as well as anaerobic ammonia oxidation, a low-carbon and energy-saving biological denitrification technology. When using zeolite adsorption and aerobic biological regeneration for nitrification of ammonia nitrogen wastewater, the influent often contains high levels of calcium and magnesium hardness. If ammonia nitrogen wastewater containing calcium and magnesium ions is exposed to the zeolite filter media for a long time, the filter media will become compacted, and calcium carbonate scale will form inside the filter media, blocking the filter media pores and affecting the overall adsorption-regeneration nitrification effect. Furthermore, the water cannot be evenly distributed, and the ammonia nitrogen conversion effect will deteriorate sharply, with the ammonia nitrogen nitrification conversion rate decreasing by more than 80%. The filter column is pickled and soaked using sulfamic acid, citric acid, and hydrochloric acid. The pH value of the pickling soaking is controlled to be 2 to 5, and the soaking time is 1 to 6 hours. After pickling, the pickling liquid is discharged, and the adsorption-aerobic biological regeneration nitrosation effect of the zeolite filter column is quickly restored, that is, the scaling and clogging problem of the zeolite filler column is solved. The activity of microbial ammonia oxidizing bacteria (AOB) is restored faster, making it less affected by the pickling, while nitrite oxidizing bacteria (NOB) are eliminated by the pickling, and the nitrite accumulation rate (NAR) quickly reaches more than 90%. This method is also suitable for rapid startup of the reactor to elute NOB. Due to the fast enrichment rate of ammonia oxidizing bacteria (AOB), the reactor quickly eliminates miscellaneous bacteria, retains AOB, and ensures stable nitrosation. The method of the present invention provides a method for efficiently restoring the effect of the biofilm method of long-term use of zeolite filter columns, realizing stable nitrosation and low-carbon and energy-saving treatment of ammonia nitrogen wastewater.

[0032] The present invention has the following advantages and technical effects:

[0033] The present invention ensures that ammonia nitrogen wastewater meets the treatment standards through adsorption treatment, and the adsorbed ammonia nitrogen is converted into nitrite through biological desorption. In actual engineering applications, the zeolite filter column is exposed to ammonia nitrogen wastewater containing calcium and magnesium ions for a long time, causing the filter material to clump and scale, and the adsorption / regeneration filter reactor effect to deteriorate. The nitrosation conversion rate of ammonia nitrogen can be reduced by using this method. The scale ammonia oxidizing bacteria in the filter pores cleaned with diluted acid are less affected by acid washing, and the filter column adsorption-aerobic biological regeneration nitrosation effect is quickly restored. At the same time, it can also achieve the rapid elimination of miscellaneous bacteria in the initial startup of the reactor, retain AOB, and achieve stable nitrosation and low-carbon and energy-saving treatment of ammonia nitrogen wastewater. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the device for implementing the present invention; wherein: 1-ammonia nitrogen wastewater inlet tank; 2-water inlet pump; 3-water inlet valve; 4-adsorption-regeneration filter media reactor; 5-zeolite; 6-water outlet valve; 7-adsorption outlet tank; 8-nitrite liquid storage tank; 9-desorption outlet valve; 10-aeration valve; 11-aeration fan; 12-alkalinity dosing tank; 13-dosing pump; 14-dosing valve; 15-diluted acid dosing tank.

[0035] Figure 2This is a graph showing the analysis results of microorganisms at the genus level before and after the use of acid. DETAILED DESCRIPTION

[0036] The present invention will be further described below with reference to the accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0037] The present invention belongs to the field of environmental engineering and provides a method for efficiently recovering the nitrosation activity of ammonia nitrogen wastewater based on zeolite adsorption-aerobic biological regeneration. The schematic diagram of the device for realizing the method for recovering the nitrosation activity of ammonia nitrogen wastewater by adsorption-regeneration is shown in FIG. Figure 1 The device comprises an ammonia nitrogen wastewater inlet tank 1, an adsorption-regeneration filter media reactor 4, an adsorption outlet tank 7, a nitrite liquid storage tank 8, an alkali solution dosing tank 12, and a dilute acid solution dosing tank 15.

[0038] The ammonia nitrogen wastewater inlet pool 1 enters the adsorption-regeneration filter material reactor 4 through the water inlet pump (centrifugal pump) 2. The adsorption-regeneration filter material column reactor 4 is provided with a water inlet and a water outlet. The water inlet is introduced into the actual ammonia nitrogen wastewater. The connected pipeline is provided with a water inlet pump 2 and a water inlet valve 3. The adsorption effluent is discharged into the adsorption effluent pool 7, and the desorption effluent is discharged into the nitrite liquid storage tank 8.

[0039] A water outlet valve 6 is provided on the pipe of the adsorption water outlet pool 7 .

[0040] A desorption water outlet valve 9 is provided on the pipeline of the nitrite liquid water storage tank 8 .

[0041] The adsorption-regeneration filter column reactor 4 is filled with zeolite 5 , and the bottom is connected to an aeration fan 11 . The alkalinity dosing tank 12 and the diluted acid dosing tank 15 are connected to pipelines and enter the adsorption-regeneration filter column reactor 4 .

[0042] The aeration blower 11 is connected to the adsorption-regeneration filter column reactor 4 through a pipeline, and an aeration valve 10 is provided on the pipeline.

[0043] The alkalinity dosing barrel 12 is connected to the adsorption-regeneration filter column reactor 4 through a pipeline, and the alkaline solution is pumped into the adsorption-regeneration filter column reactor 4 through a dosing pump (metering pump) 13. A dosing valve 14 is provided for regulation.

[0044] In actual engineering application, the filter media produces caking and scaling, and the effect of the adsorption-regeneration filter media reactor 4 deteriorates. By introducing a diluted acid solution 15 into the adsorption-regeneration filter media column reactor 4, the adsorption-aerobic biological regeneration nitritation effect of the zeolite filter media column is quickly restored, thereby solving the scaling and clogging problem of the zeolite packing column and preventing the biotransformation microorganism ammonia oxidizing bacteria (AOB) from being affected by acid washing.

[0045] The system of the present invention comprises the following steps when applied:

[0046] During the adsorption stage, the ammonia nitrogen wastewater in the ammonia nitrogen wastewater inlet pool 1 is continuously pumped into the adsorption-regeneration filter column reactor 4 through the water inlet pump 2. As the adsorption proceeds, the effluent is discharged into the adsorption effluent pool 7. The ammonia nitrogen concentration in the effluent will gradually increase. When the ammonia nitrogen concentration in the effluent reaches the ammonia nitrogen concentration limit in the sewage discharge standard, the water inlet is stopped, and the water inlet valve 3 and the water outlet valve 6 are closed. After the water inlet is stopped, the aeration fan 11 is turned on to introduce aeration into the adsorption-regeneration filter column reactor 4 for internal circulation aeration, biodesorption and desorption. Alkalinity is added during aeration at the same time. The alkali solution in the alkalinity dosing tank 12 is pumped into the adsorption-regeneration filter column reactor 4 through the dosing pump 13, and a nitrosation reaction occurs to convert ammonia nitrogen into nitrite. Nitrate, when the nitrite concentration of the desorbed water reaches a preset value, the dosing pump 13 is turned off, the dosing valve 14 is closed, the desorption water outlet valve 9 is opened, and the desorbed water flows into the nitrite liquid storage tank 8 to obtain nitrite wastewater; in engineering applications, zeolite adsorption-aerobic biological regeneration of ammonia nitrogen wastewater nitrosation is used, and the influent often contains high hardness such as calcium and magnesium. When ammonia nitrogen wastewater containing calcium and magnesium ions enters the zeolite filter column for a long time, the filter material will become compacted, and calcium carbonate scale will be generated inside to block the pores of the filter material, affecting the overall adsorption-regeneration nitrosation effect; the water cannot be evenly distributed, and the ammonia nitrogen conversion effect will also deteriorate sharply, and the ammonia nitrogen nitrosation conversion rate will drop by more than 80%. Add dilute acid solution to the dilute acid solution dosing barrel 15, and use the dilute acid solution to pickle and soak the zeolite filter material 5. The pH value of the pickling and soaking is controlled to be 2-5, and the soaking time is 1-6 hours. After pickling, the pickling liquid is discharged, and the adsorption-aerobic biological regeneration nitritation effect of the zeolite filter material column is quickly restored, which solves the scaling and clogging problem of the zeolite packing column, and makes the biotransformation microorganisms ammonia oxidizing bacteria (AOB) unaffected by the pickling and NOB is eliminated, and the nitrite accumulation rate (NAR) quickly reaches more than 90%.

[0047] When a reactor needs to quickly start nitrosation, this method can be used to elutriate NOB. Due to the rapid enrichment of ammonia-oxidizing bacteria (AOB), the reactor quickly eliminates contaminants while retaining AOB, ensuring stable nitrosation. Adding appropriate activated sludge for sludge acclimation is a necessary step in starting a nitrosating bioreactor. To enrich the AOB strains required for nitrosation, the addition of dilute acid can effectively eliminate NOB and achieve stable nitrosation.

[0048] Example 1:

[0049] A method for efficiently recovering the nitrosation activity of ammonia nitrogen wastewater based on zeolite adsorption-aerobic biological regeneration, comprising the following steps:

[0050] 1. Fill the adsorption-regeneration filter column reactor with 20 tons of 40-mesh artificial zeolite filler, and the effective volume of the reactor is 30m 3The influent ammonia nitrogen concentration of the ammonia nitrogen wastewater is 90-120 mg / L, the influent nitrate nitrogen concentration is 40-60 mg / L, and the pH is 8.5-9.5. Ammonia nitrogen wastewater is introduced, and after 3 hours of adsorption, when the effluent ammonia nitrogen is close to 15.0 mg / L, the adsorption is stopped; after stopping the adsorption, aeration is turned on, the dissolved oxygen is 5.0 mg / L, and alkali solution is pumped into the reactor, and sodium bicarbonate is added in an amount of 0.6-1 g / L. After 12 hours of aeration operation, the nitrite nitrogen concentration exceeds 100 mg / L, the nitrite nitrogen accumulation rate (NAR) exceeds 90%, and the desorption of the reactor is completed;

[0051] 2. The influent contains high hardness such as calcium and magnesium. When ammonia nitrogen wastewater containing calcium and magnesium ions enters the zeolite filter column for a long time, the filter material will become compacted. At the same time, calcium carbonate scale will be generated inside the filter material to block the pores of the filter material, affecting the overall adsorption-regeneration nitrification effect. After 24 hours of aeration and desorption operation, the nitrite nitrogen concentration was only 33.49 mg / L, and the nitrification conversion rate of ammonia nitrogen dropped by more than 80%, failing to achieve the expected target.

[0052] 3. Use a diluted hydrochloric acid (1 mol / L) solution to remove scale from the reactor filter media. The pH is controlled at 2, and the soaking time is 1 hour. The diluted acid solution does not filter the filter media. During this period, cyclic aeration is turned on at an aeration frequency of 50 Hz. The diluted acid solution is affected by aeration to flush the filter media surface, improving the compaction of the filter media. The scale in the filter media pores floats on the surface of the water body and is discharged with the water flow, and the nitrification effect of the reactor is quickly restored. After acid washing, the next cycle is biological desorption. After 20 hours of operation, the nitrite nitrogen concentration in the desorbed water reaches 152.53 mg / L, and the NAR exceeds 90%, achieving efficient enrichment of AOB and elimination of NOB.

[0053] The data of Example 1 are shown in Table 1 below.

[0054] Table 1. Example data of dilute hydrochloric acid pickling activity recovery

[0055]

[0056] The high-throughput analysis of microorganisms was performed on the filter media biological samples. Figure 2 As shown, in the genus level analysis of the taxonomic composition analysis, the proportion of Nitrosomonas decreased from 2.88% to 0.32% during system operation, and increased to 17.08% after using diluted acid during operation, which means that the system activity has recovered.

[0057] Example 2:

[0058] 1. When ammonia nitrogen wastewater containing calcium and magnesium ions enters the zeolite filter column for a long time, the filter material will become compacted, and calcium carbonate scale will be generated inside to block the filter material pores, affecting the overall adsorption-regeneration nitritation effect. After 24 hours of aeration and desorption operation, the nitrite nitrogen concentration is only 22.72 mg / L, and the nitritation conversion rate of ammonia nitrogen will drop by more than 80%, far from the expected target;

[0059] 2. Aminosulfonic acid (99%) acid solution was used to remove scale from the reactor filter media. The diluted acid solution was not added to the filter media, the pH was controlled at 5, and the filter media was soaked for 6 hours. During this period, cyclic aeration was turned on with an aeration frequency of 20 Hz. The diluted acid solution was affected by aeration to flush the filter media surface, improving the compaction phenomenon of the filter media. The scale in the filter media pores floated on the water surface and was discharged with the water flow. The nitritation effect of the reactor was quickly restored. After acid washing, biological desorption was carried out in the next cycle. The desorption stage was operated for 20 hours. The nitrite nitrogen concentration of the desorbed water was 130.48 mg / L, and the NAR exceeded 90%.

[0060] The data of Example 2 are shown in Table 2 below.

[0061] Table 2. Data of aminosulfonic acid pickling activity recovery example

[0062]

[0063] Example 3

[0064] 1. When ammonia nitrogen wastewater containing calcium and magnesium ions enters the zeolite filter column for a long time, the filter material will become compacted, and calcium carbonate scale will be generated inside to block the filter material pores, affecting the overall adsorption-regeneration nitritation effect. After 24 hours of aeration and desorption operation, the nitrite nitrogen concentration is only 52.75 mg / L, and the nitritation conversion rate of ammonia nitrogen will drop by more than 50%, far from the expected target;

[0065] 2. Use citric acid diluted acid solution to remove scale on the reactor filter media, control the pH to 4, soak for 3 hours, the diluted acid solution does not filter the media, start the circulation aeration, the aeration frequency is 30Hz, the diluted acid solution is affected by aeration to flush the filter media surface, improve the filter media compaction phenomenon, the scale in the filter media pores floats on the water surface and is discharged with the water flow, the reactor nitritation effect is quickly restored, after acid washing, the next cycle is biological desorption, the desorption stage runs for 20 hours, the nitrite nitrogen concentration of the desorbed water is 126.10 mg / L, and the NAR exceeds 90%.

[0066] The data of Example 3 are shown in Table 3 below.

[0067] Table 3. Citric acid pickling activity recovery example data table

[0068]

[0069] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the described embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A method for efficient startup and activity recovery of nitrosation of ammonia nitrogen wastewater based on zeolite adsorption-aerobic biological regeneration, characterized by: The steps include: S1. Treat ammonia nitrogen wastewater using an adsorption-aerobic biological regeneration method, select zeolite as the adsorption-aerobic biological regeneration filter material, use a diluted acid solution to clean the adsorption-regeneration filter material column, and control the pH value to 2-5 without filtering the filter material. The soaking time is 1-6 hours; start the circulating aeration at an aeration frequency of 20-50 Hz; discharge the acid wash solution, and start the nitrosation effect of the adsorption-regeneration filter material column; S2. Ammonia nitrogen wastewater is introduced into the adsorption-regeneration filter column. As adsorption proceeds, when the ammonia nitrogen concentration in the effluent reaches the ammonia nitrogen concentration limit specified in the sewage discharge standard, water inlet is stopped. After water inlet is stopped, aeration is introduced into the adsorption-regeneration filter column to perform internal circulation aerobic aeration biodesorption. At the same time, alkalinity is added to cause a nitrification reaction to convert ammonia nitrogen into nitrite. The obtained nitrite wastewater is supplied to the short-cut nitrification, denitrification, and anaerobic ammonium oxidation sections. S3, repeating step S2, when the filter material agglomerates, the ammonia nitrogen concentration in the effluent is higher than the ammonia nitrogen concentration limit in the sewage discharge standard, and the converted nitrite concentration is lower than the average value, using dilute acid to clean the adsorption-regeneration filter material column, the dilute acid does not contain the filter material, the pH value is controlled to be 2-5, and the soaking time is 1-6 hours; starting the circulating aeration at an aeration frequency of 20-50 Hz; discharging the acid wash solution, and the adsorption-regeneration filter material column adsorption-regeneration nitrosation effect is restored, and then continuing to repeat step S2; The acid solution in steps S1 and S3 is any one or more of hydrochloric acid, sulfamic acid, and citric acid; The ammonia nitrogen wastewater in step S2 has an influent ammonia nitrogen concentration of 90-120 mg / L, an influent nitrate nitrogen concentration of 40-60 mg / L, and a pH of 8.5-9.5; After adding alkalinity in step S2, the pH is adjusted to 8.5-9.

5.

2. The method for efficient startup and activity recovery of ammonia nitrogen wastewater nitrosation based on zeolite adsorption-aerobic biological regeneration according to claim 1 is characterized in that: The zeolite described in steps S1 and S3 is a natural zeolite or artificial zeolite having the ability to adsorb ammonia nitrogen; The zeolite described in steps S1 and S3 is 40±10 mesh.

3. The method for efficient startup and activity recovery of ammonia nitrogen wastewater nitrosation based on zeolite adsorption-aerobic biological regeneration according to claim 1 is characterized in that: The aeration conditions described in step S2 are: dissolved oxygen concentration 5.0±1 mg / L, and time 12±4 h.

4. The method for efficient startup and activity recovery of ammonia nitrogen wastewater nitrosation based on zeolite adsorption-aerobic biological regeneration according to claim 1 is characterized in that: After adding alkalinity in step S2, the pH is adjusted to 8.5-9.

5.

5. A method for using an adsorption-regeneration ammonia nitrogen wastewater nitrification device, characterized by: The adsorption-regeneration ammonia nitrogen wastewater nitrification device comprises an ammonia nitrogen wastewater inlet pool (1), an adsorption-regeneration filter material reactor (4), an adsorption outlet pool (7), a nitrification liquid storage pool (8), an alkali solution dosing tank (12), and a dilute acid solution dosing tank (15); The ammonia nitrogen wastewater inlet pool (1) enters the adsorption-regeneration filter material reactor (4) through the water inlet pump (2). The adsorption-regeneration filter material reactor (4) is provided with a water inlet and a water outlet. The water inlet is fed with actual ammonia nitrogen wastewater. The connected pipeline is provided with a water inlet pump (2) and a water inlet valve (3). The adsorption effluent is discharged into the adsorption effluent pool (7), and the desorption effluent is discharged into the nitrite liquid storage tank (8). The adsorption water outlet pool (7) is provided with a water outlet valve (6) on the pipeline; The nitrite liquid storage tank (8) is provided with a desorption water outlet valve (9) on the pipeline; The adsorption-regeneration filter material reactor (4) is filled with zeolite (5), the bottom of which is connected to an aeration fan (11), and the alkalinity dosing tank (12) and the diluted acid dosing tank (15) are connected to the adsorption-regeneration filter material reactor (4) through pipes; The aeration fan (11) is connected to the adsorption-regeneration filter material reactor (4) through a pipeline, and an aeration valve (10) is provided on the pipeline; The alkalinity dosing barrel (12) is connected to the adsorption-regeneration filter material reactor (4) via a pipeline, and the alkaline solution is pumped into the adsorption-regeneration filter material reactor (4) via a dosing pump (13), and a dosing valve (14) is provided for regulation; The dilute acid solution dosing barrel (15) is connected to the adsorption-regeneration filter material reactor (4) via a pipeline and is used to add the dilute acid solution; The method of use comprises the following steps: 1) Add dilute acid to the dilute acid dosing tank (15), and use the dilute acid to clean the filter media in the adsorption-regeneration filter media reactor (4). The dilute acid does not filter the filter media, and the pH value is controlled to be 2-5, and the soaking time is 1-6 hours; start the circulating aeration, and the aeration frequency is 20-50Hz; discharge the acid wash liquid, and start the nitrosation effect of the adsorption-regeneration filter media column; 2) Operate the equipment according to the adsorption-aerobic biological regeneration method; when the filter media agglomerates, the ammonia nitrogen concentration in the effluent is higher than the ammonia nitrogen concentration limit in the sewage discharge standard, and the converted nitrite concentration is lower than the average value, stop the operation, add dilute acid to the dilute acid dosing tank (15), and use the dilute acid to clean the filter media in the adsorption-regeneration filter media reactor (4). The dilute acid does not filter the filter media, and the pH value is controlled to be 2-5, and the soaking time is 1-6 hours; start the circulating aeration, and the aeration frequency is 20-50Hz; discharge the acid wash liquid, and the nitrification effect of the adsorption-regeneration filter media column is restored, and then continue to operate the equipment according to the adsorption-aerobic biological regeneration method; The equipment operated according to the adsorption-aerobic biological regeneration method is as follows: the ammonia nitrogen wastewater in the ammonia nitrogen wastewater inlet pool (1) is continuously pumped into the adsorption-regeneration filter material reactor (4) through the water inlet pump (2); as the adsorption proceeds, the effluent is discharged into the adsorption effluent pool (7); the ammonia nitrogen concentration in the effluent gradually increases; when the ammonia nitrogen concentration in the effluent reaches the ammonia nitrogen concentration limit in the sewage discharge standard, the water inlet is stopped, and the water inlet valve (3) and the water outlet valve (6) are closed; after the water inlet is stopped, the aeration fan (11) is turned on to aspirate the ammonia nitrogen in the wastewater. The adsorption-regeneration filter media reactor (4) is aerated to carry out internal circulation aeration biodesorption. Alkalinity is added during aeration. The alkali solution in the alkalinity dosing tank (12) is pumped into the adsorption-regeneration filter media reactor (4) through the dosing pump (13). A nitrification reaction occurs to convert ammonia nitrogen into nitrite. When the nitrite concentration of the desorbed water reaches a preset value, the dosing pump (13) is closed, the dosing valve (14) is closed, and the desorption outlet valve (9) is opened. The desorbed outlet water flows into the nitrite liquid storage tank (8) to obtain nitrite wastewater.

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