Rapid culture method of sulfur autotrophic denitrifying bacteria

Abstract

The invention provides a rapid culture method of sulfur autotrophic denitrification bacteria. The rapid culture method comprises the following steps: S100, preparing an autotrophic denitrification filler; s200, inoculating the activated sludge into a reaction device; s300, adjusting reaction conditions; in S100, the autotrophic denitrification filler comprises reduced sulfur, nitrate nitrogen and sewage containing nitrate nitrogen; in terms of elemental sulfur, the concentration of the reduced sulfur content reaches 450 mg / L-550 mg / L, and in terms of nitrogen, the concentration of the nitrate nitrogen content reaches 200 mg / L-300 mg / L; in the step S300, adjusting the reaction conditions comprises the following steps: S310, adding a buffering agent into the reaction device, and adjusting the initial pH of the reaction; s320, the content of reduced sulfur and the content of nitrate nitrogen in the reaction device are detected every 1-2 hours, the detection result is the ratio of the content of reduced sulfur to the content of nitrate nitrogen, and an adjusting component is added into the reaction device according to the detection result. The technical problem to be solved by the invention is to accurately control the pH value of the reaction while solving the rapid culture of the sulfur autotrophic denitrifying bacteria, reduce unnecessary waste and realize reasonable utilization of resources.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a method for rapidly culturing sulfur autotrophic denitrifying bacteria. Background Art

[0002] Sulfur autotrophic denitrification refers to the use of reduced sulfur such as elemental sulfur, sulfite, hydrosulfuric acid, and hydrogen sulfide as electron donors and energy substances to reduce nitrate or nitrite to nitrogen gas under the action of microorganisms, thereby achieving the purpose of denitrification without adding organic carbon, and at the same time oxidizing the reduced sulfur to sulfate.

[0003] In the prior art, sulfur autotrophic denitrifying bacteria account for a relatively low proportion in conventional activated sludge treatment systems, have relatively strict requirements on the living environment, and are extremely easy to be lost. Therefore, the sulfur autotrophic denitrification process generally has the problem of a long startup cycle. In recent years, solving the problem of slow proliferation and difficult enrichment of sulfur autotrophic denitrifying bacteria has become a research hotspot in the field of sulfur autotrophic denitrification. However, among the various improvement methods, there is a problem that cannot be ignored, that is, the control of pH. The pH value is recognized as one of the most difficult control variables. Too high or too low pH values ​​will affect the sulfur autotrophic denitrification reaction.

[0004] A Chinese patent document with publication number CN115304159B discloses a broad-spectrum adaptable autotrophic denitrification filter material and a preparation method thereof, which includes a main functional active component for denitrification and an auxiliary component with a slow-release neutralization capability. The filter material adopts a two-component form, and a neutralizer component with a slow-release function is added to the reaction system to eliminate hydrogen ions generated during the denitrification process. The auxiliary component is present in the entire reaction process from the addition of reactants to the completion of the reaction. The control of pH is reflected in the slow-release rate, but the slow-release rate is affected by many factors and is unstable, and the change in pH value cannot be accurately adjusted.

[0005] The reaction pH is adjusted by real-time detection of pH changes. Since there is a certain lag between the pH meter's displayed value and its actual value, it is difficult to control the amount of buffer when adjusting the reaction pH. In addition, the reaction is carried out in a reactor with a large volume. After the pH buffer is added, it takes a certain amount of time to complete the neutralization reaction, which not only makes it difficult to control the pH value, but also easily leads to over-adjustment, resulting in a large amount of waste of acid and alkali neutralizers, and even causes the pH value of the drainage to exceed the standard. Therefore, while solving the problem of rapid cultivation of sulfur autotrophic denitrifying bacteria, it is necessary to accurately control the pH of the reaction, reduce unnecessary waste, and achieve rational use of resources. Summary of the invention

[0006] The technical problem solved by the invention is to provide a method for rapidly culturing sulfur autotrophic denitrifying bacteria, which can accurately control the pH of the reaction, reduce unnecessary waste and realize the rational use of resources while solving the problem of rapidly culturing sulfur autotrophic denitrifying bacteria.

[0007] In order to solve the above problems, the present invention provides a rapid cultivation method of sulfur autotrophic denitrifying bacteria, comprising: S100, preparing an autotrophic denitrification filler, and adding the autotrophic denitrification filler to a reaction device of an autotrophic denitrification system; S200, inoculating activated sludge into the reaction device; S300, adjusting reaction conditions; in S100, the autotrophic denitrification filler comprises reduced sulfur, nitrate nitrogen and sewage containing nitrate nitrogen; the reduced sulfur content is calculated as elemental sulfur, and the concentration reaches 450mg / L~550mg / L; the nitrate nitrogen content is calculated as nitrogen, and the concentration reaches 200mg / L~300mg / L; in S300, adjusting the reaction conditions comprises: S310, adding a buffer to the reaction device, and adjusting the initial pH of the reaction; S320, detecting the reduced sulfur content and the nitrate nitrogen content in the reaction device every 1~2 hours, and the detection result is the ratio of the reduced sulfur content to the nitrate nitrogen content. According to the detection results, adjusting components are added to the reaction device, and the adjusting components include: a first adjusting component, the first adjusting component includes a first reduced sulfur, a first nitrate nitrogen, and a first buffer, and the mass ratio is (4-7): (4-7): (1-5); a second adjusting component, the second adjusting component includes a second reduced sulfur and a second buffer, and the mass ratio is (15-18): (6-8); a third adjusting component, the third adjusting component includes a second nitrate nitrogen and a third buffer, and the mass ratio is (9-11): (6-8); until the load rate reaches the design value, stop adding the adjusting components; the addition amount of the first reduced sulfur and the second reduced sulfur is calculated in terms of elemental sulfur, and the reduced sulfur concentration in the reaction device is controlled to reach 450mg / L~550mg / L, and the addition amount of the first nitrate nitrogen and the second nitrate nitrogen is calculated in terms of nitrogen, and the nitrate nitrogen concentration in the reaction device is controlled to reach 200mg / L~300mg / L.

[0008] Compared with the prior art, the technical effect achieved by the technical scheme is as follows: by preparing a sulfur autotrophic denitrification filler, wherein the autotrophic denitrification filler includes reduced sulfur, nitrate nitrogen and sewage containing nitrate nitrogen; the reduced sulfur concentration in the reaction device reaches 450mg / L-550mg / L, and the nitrate nitrogen concentration reaches 200mg / L-300mg / L; sufficient nutrient substrate is provided for the growth of sulfur autotrophic denitrifying bacteria. In the present application, a method of adding regulating components in batches is adopted to maintain stable growth conditions for cultivating sulfur autotrophic denitrifying bacteria. Combined with the actual situation of rapid cultivation of sulfur autotrophic denitrifying bacteria, since the reaction is carried out in a reaction device with a large volume, after the pH buffer is added, the pH meter has a certain hysteresis between the instrument display value and the actual value of the pH measurement. Therefore, when adjusting the reaction pH, it is not easy to control the amount of the buffer, and the acid-base neutralization process presents a serious nonlinear characteristic, which makes the chemical reaction relatively slow, not only causing great difficulties in pH control, but also prone to over-adjustment, resulting in a large amount of waste of acid and alkali neutralizers, and even causing the pH value of the drainage to exceed the standard. The sulfur autotrophic denitrification reaction with elemental sulfur and reduced sulfur as electron donors is an acidogenic reaction. The reduced sulfur and nitrate nitrogen related to the pH change are used to set regulating components. The reaction pH is adjusted while adjusting the elemental sulfur concentration and nitrogen concentration. After an interval of 1 to 2 hours, the reduced sulfur concentration and nitrate nitrogen concentration in the reaction device decrease and exceed the lower limit of the set concentration range. At this time, the regulating components are added to adjust the reduced sulfur concentration and nitrate nitrogen concentration in the reaction device, wherein the first regulating component includes the first reduced sulfur, the first nitrate nitrogen, and the first buffer in a mass ratio of (4-7):(4-7):(1-5); the second regulating component includes the second reduced sulfur and the second buffer in a mass ratio of (15-18):(6-8); the third regulating component includes the second nitrate nitrogen and the third buffer in a mass ratio of (9-11):(6-8); the regulating components are added according to the detection results to adjust the reduced sulfur concentration and the nitrate nitrogen concentration to the set concentration range. At the same time, the regulating components also include a corresponding proportion of buffers to maintain the stability of the pH within this time period.

[0009] In one example of the present invention, when the detection result is equal to the set ratio, the first adjusting component is added to the reaction device; and / or when the detection result is greater than the set ratio, the first adjusting component and the second adjusting component are added to the reaction device; and / or when the detection result is less than the set ratio, the first adjusting component and the third adjusting component are added to the reaction device.

[0010] Compared with the prior art, the technical effect achieved by adopting the technical solution is as follows: the ratio is set to be the ratio of the preset reduced sulfur concentration and the preset nitrate nitrogen concentration in the reaction device. When the detection result is equal to the set ratio, the consumption of the reduced sulfur content and the consumption of the nitrate nitrogen content in the reaction device are equal to the set ratio, the first regulating component is supplemented, the ratio of the reduced sulfur concentration and the nitrate nitrogen concentration in the first regulating component is equal to the set ratio, and with the addition of the first regulating component, the reduced sulfur concentration and the nitrate nitrogen concentration return to the initial state, and at the same time the first buffer is added to supplement the reaction according to the ratio. The alkalinity consumed in the device; when the test result is greater than the set ratio, the content of reduced sulfur in the reaction device is too much, and the second adjusting component needs to be added while supplementing the first adjusting component to make up for the extra reduced sulfur loss. The first buffer and the second buffer are added according to the proportion to supplement the alkalinity consumed in the reaction device; when the test result is less than the set ratio, the content of nitrate nitrogen in the reaction device is too much, and the third adjusting component needs to be added while supplementing the first adjusting component to make up for the extra nitrate nitrogen loss. The first buffer and the third buffer are added according to the proportion to supplement the alkalinity consumed in the reaction device.

[0011] In one embodiment of the present invention, the reduced sulfur includes one or more of sodium thiosulfate, sodium sulfite, and hydrosulfuric acid; and / or the first reduced sulfur includes one or more of sodium thiosulfate, sodium sulfite, and hydrosulfuric acid; and / or the second reduced sulfur includes one or more of sodium thiosulfate, sodium sulfite, and hydrosulfuric acid.

[0012] Compared with the prior art, the technical effect achieved by adopting the technical solution is as follows: combined with the actual situation of sulfur autotrophic denitrifying bacteria cultivation, the reduced sulfur during startup and operation is the sulfur autotrophic filler in the system. Since the reduced sulfur on the sulfur autotrophic filler is slightly soluble in water, it is difficult to have a certain concentration of reduced sulfur in the system during startup, resulting in slow growth of sulfur autotrophic bacteria. By adding easily soluble reduced sulfur, the reaction device is provided with sufficient nutrient substrate.

[0013] In one example of the present invention, the nitrate nitrogen includes one or more of sodium nitrate and sodium nitrite; and / or the first nitrate nitrogen includes one or more of sodium nitrate and sodium nitrite; and / or the second nitrate nitrogen includes one or more of sodium nitrate and sodium nitrite.

[0014] Compared with the prior art, the technical effect achieved by adopting the technical scheme is as follows: combined with the actual situation of cultivating sulfur autotrophic denitrifying bacteria, the nitrate nitrogen in the startup and operation process is the nitrate nitrogen in the pre-treatment process of the system, and its concentration often cannot reach the concentration required for the rapid growth of sulfur autotrophic bacteria. For projects with low nitrate nitrogen concentration in raw water, the nitrate nitrogen concentration in the incoming water of the sulfur autotrophic reaction device is often low, and cannot provide a high-concentration nitrate nitrogen nutrient substrate for the rapid growth of sulfur autotrophic bacteria. By adding nitrate nitrogen, the nitrate nitrogen content in the reaction device meets the rapid growth requirements of sulfur autotrophic denitrifying bacteria.

[0015] In one example of the present invention, the buffer includes one or more of caustic soda, sodium carbonate, and sodium bicarbonate; and / or the second buffer includes one or more of caustic soda, sodium carbonate, and sodium bicarbonate; and / or the third buffer includes one or more of caustic soda, sodium carbonate, and sodium bicarbonate.

[0016] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: the sulfur autotrophic denitrification reaction with elemental sulfur and reduced sulfur as electron donors is an acid-producing reaction, the pH value range suitable for the growth of sulfur autotrophic denitrifying bacteria is 6.5-7.8, and an alkaline buffer needs to be supplemented.

[0017] In one embodiment of the present invention, the autotrophic denitrification filler further includes trace elements, and the trace elements include one or more configuration agents of iron, dipotassium hydrogen phosphate, and cobalt salt.

[0018] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: by adding trace elements to the autotrophic denitrification filler, suitable nutritional conditions are provided for the growth of sulfur autotrophic denitrifying bacteria.

[0019] In one embodiment of the present invention, in S200, the activated sludge is calculated as dry sludge, accounting for 1 kg / m of the effective volume of the reaction device. 3 ~1.5Kg / m 3 .

[0020] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: combined with the actual situation of sulfur autotrophic denitrifying bacteria cultivation, the conventional bacteria are generally added with activated sludge from domestic sewage treatment plants, and the concentration of reduced sulfur in the sewage from domestic sewage treatment plants is very low, so the proportion of sulfur autotrophic bacteria is low, and the start-up speed of using domestic sewage treatment plant sludge as bacteria is slow. By giving priority to selecting activated sludge from sewage treatment plants with high reduced sulfur content in raw water as bacteria, and the activated sludge, calculated as dry sludge, accounts for 1Kg / m of the effective volume of the reaction device. 3 ~1.5Kg / m 3 , so that the reaction device has a certain amount of starting bacteria.

[0021] In one embodiment of the present invention, S300 includes controlling the reaction temperature in a control range of 20°C to 35°C.

[0022] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: by controlling the reaction temperature, the temperature is controlled at 20°C~35°C, which is suitable for the growth of sulfur autotrophic denitrifying bacteria and is conducive to the rapid enrichment of sulfur autotrophic denitrifying bacteria.

[0023] In one example of the present invention, S300 includes backwashing and aeration, the backwashing includes air washing and water washing, and the backwashing time is 4 to 6 minutes.

[0024] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: aeration can promote the circulation of substances in the mixed liquid, realize sufficient contact and mixing of activated sludge and sewage, and solve the problem of packing compaction and blockage through backwashing.

[0025] In one embodiment of the present invention, the flow rate of water washing is controlled to be 15m / m 2 h, the flow rate of air washing is controlled at 30m / m 2 h, normal operating flow rate is 4m / m 2 h, the backwash cycle is 6 to 8 days. DETAILED DESCRIPTION

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is described in detail below in conjunction with specific embodiments.

[0027] The invention provides a rapid culture method of sulfur autotrophic denitrifying bacteria, comprising: S100, preparing an autotrophic denitrification filler, and adding the autotrophic denitrification filler to a reaction device of an autotrophic denitrification system; S200, inoculating activated sludge into the reaction device; S300, adjusting reaction conditions; in S100, the autotrophic denitrification filler comprises reduced sulfur, nitrate nitrogen and sewage containing nitrate nitrogen; the reduced sulfur content is calculated as elemental sulfur, and the concentration reaches 450mg / L-550mg / L; the nitrate nitrogen content is calculated as nitrogen, and the concentration reaches 200mg / L-300mg / L; in S300, adjusting the reaction conditions comprises: S310, adding a buffer to the reaction device, and adjusting the initial pH of the reaction; S320, detecting the reduced sulfur content and the nitrate nitrogen content in the reaction device every 1-2 hours, wherein the detection result is the ratio of the reduced sulfur content to the nitrate nitrogen content, and adjusting the reduced sulfur content and the nitrate nitrogen content according to the detection result. According to the test results, regulating components are added to the reaction device, and the regulating components include: a first regulating component, the first regulating component includes a first reduced sulfur, a first nitrate nitrogen, and a first buffer, and the mass ratio is (4-7): (4-7): (1-5); a second regulating component, the second regulating component includes a second reduced sulfur and a second buffer, and the mass ratio is (15-18): (6-8); a third regulating component, the third regulating component includes a second nitrate nitrogen and a third buffer, and the mass ratio is (9-11): (6-8); until the load rate reaches the design value, stop adding the regulating components; the first reduced sulfur and the second reduced sulfur are added in an amount based on elemental sulfur, and the reduced sulfur concentration in the reaction device is controlled to reach 450mg / L~550mg / L, and the first nitrate nitrogen and the second nitrate nitrogen are added in an amount based on nitrogen, and the nitrate nitrogen concentration in the reaction device is controlled to reach 200mg / L~300mg / L.

[0028] Specifically, by preparing a sulfur autotrophic denitrifying filler, wherein the autotrophic denitrifying filler includes reduced sulfur, nitrate nitrogen and sewage containing nitrate nitrogen; the reduced sulfur concentration in the reaction device reaches 450mg / L~550mg / L, and the nitrate nitrogen concentration reaches 200mg / L~300mg / L; sufficient nutrient substrate is provided for the growth of sulfur autotrophic denitrifying bacteria. In the present application, a method of adding regulating components in batches is adopted to maintain stable growth conditions for cultivating sulfur autotrophic denitrifying bacteria. Combined with the actual situation of rapid cultivation of sulfur autotrophic denitrifying bacteria, since the reaction is carried out in a reaction device with a large volume, after the pH buffer is added, there is a certain lag between the pH value displayed on the instrument and the actual value of the pH meter when measuring the pH. Therefore, when adjusting the reaction pH, it is difficult to control the amount of the buffer, and the acid-base neutralization process presents a serious nonlinear characteristic, which makes the chemical reaction relatively slow, which not only causes great difficulty in controlling the pH value, but also easily causes over-adjustment, resulting in a large amount of waste of acid and alkali neutralizers, and even causes the pH value of the drainage to exceed the standard. The sulfur autotrophic denitrification reaction with elemental sulfur and reduced sulfur as electron donors is an acidogenic reaction. The reduced sulfur and nitrate nitrogen related to the pH change are used to set regulating components. The reaction pH is adjusted while adjusting the reduced sulfur concentration and the nitrate nitrogen concentration. After an interval of 1 to 2 hours, the reduced sulfur concentration and the nitrate nitrogen concentration in the reaction device decrease and exceed the lower limit of the set concentration range. At this time, the regulating components are added to adjust the reduced sulfur concentration and the nitrate nitrogen concentration in the reaction device. The first regulating component includes the first reduced sulfur, the first nitrate nitrogen, and the first buffer in a mass ratio of (4-7):(4-7):(1-5); the second regulating component includes the second reduced sulfur and the second buffer in a mass ratio of (15-18):(6-8); the third regulating component includes the second nitrate nitrogen and the third buffer in a mass ratio of (9-11):(6-8); the regulating component is added according to the detection result to adjust the reduced sulfur concentration and the nitrate nitrogen concentration to the set concentration range. At the same time, the regulating component also includes a corresponding proportion of buffer to maintain the stability of pH within this time period.

[0029] In one example of the present invention, when the detection result is equal to the set ratio, the first adjusting component is added to the reaction device; and / or when the detection result is greater than the set ratio, the first adjusting component and the second adjusting component are added to the reaction device; and / or when the detection result is less than the set ratio, the first adjusting component and the third adjusting component are added to the reaction device.

[0030] Specifically, in a specific embodiment, the set ratio is 2:1, which is the ratio of the preset reduced sulfur concentration and the preset nitrate nitrogen concentration in the reaction device. When the detection result is equal to 2:1, the consumption of the reduced sulfur content and the consumption of the nitrate nitrogen content in the reaction device are equal to 2:1, and the first regulating component is supplemented, wherein the mass ratio of the first regulating component is 5:6:3; the ratio of the reduced sulfur concentration and the nitrate nitrogen concentration in the first regulating component is equal to the set ratio, and with the addition of the first regulating component, the reduced sulfur concentration and the nitrate nitrogen concentration return to the initial state, and at the same time, the first buffer is added according to the ratio to supplement the alkalinity consumed in the reaction device; when the detection result is greater than the set ratio, the reduced sulfur in the reaction device is reduced. When the loss of reduced sulfur in the reactor is too much, the second regulating component needs to be added to make up for the extra loss of reduced sulfur while supplementing the first regulating component. The mass ratio of the first regulating component is 5:6:3, and the mass ratio of the second regulating component is 17:7. The first buffer and the second buffer are added to supplement the alkalinity consumed in the reaction device according to the ratio. When the test result is less than the set ratio, the loss of nitrate nitrogen in the reaction device is too much. When the first regulating component is supplemented, the third regulating component needs to be added to make up for the extra loss of nitrate nitrogen. The mass ratio of the first regulating component is 5:6:3, and the mass ratio of the third regulating component is 10:7. The first buffer and the third buffer are added to supplement the alkalinity consumed in the reaction device according to the ratio.

[0031] In one embodiment of the present invention, the reduced sulfur includes one or more of sodium thiosulfate, sodium sulfite, and hydrosulfuric acid; and / or the first reduced sulfur includes one or more of sodium thiosulfate, sodium sulfite, and hydrosulfuric acid; and / or the second reduced sulfur includes one or more of sodium thiosulfate, sodium sulfite, and hydrosulfuric acid.

[0032] Specifically, combined with the actual situation of cultivating sulfur autotrophic denitrifying bacteria, the reduced sulfur during startup and operation is the sulfur autotrophic filler in the system. Since the reduced sulfur on the sulfur autotrophic filler is slightly soluble in water, it is difficult to have a certain concentration of reduced sulfur in the system during startup, resulting in slow growth of sulfur autotrophic bacteria. By adding easily soluble reduced sulfur, the reaction device is provided with sufficient nutrient substrate. In a specific embodiment of the present invention, the reduced sulfur, the first reduced sulfur, and the second reduced sulfur are preferably sodium thiosulfate.

[0033] In one example of the present invention, the nitrate nitrogen includes one or more of sodium nitrate and sodium nitrite; and / or the first nitrate nitrogen includes one or more of sodium nitrate and sodium nitrite; and / or the second nitrate nitrogen includes one or more of sodium nitrate and sodium nitrite.

[0034] Specifically, in combination with the actual situation of cultivating sulfur autotrophic denitrifying bacteria, the nitrate nitrogen in the startup and operation process is the nitrate nitrogen in the pre-treatment process of the system, and its concentration often does not reach the concentration required for the rapid growth of sulfur autotrophic bacteria. For projects with low nitrate nitrogen concentration in raw water, the nitrate nitrogen concentration in the incoming water of the sulfur autotrophic reaction device is often low, and cannot provide a high-concentration nitrate nitrogen nutrient substrate for the rapid growth of sulfur autotrophic bacteria. By adding nitrate nitrogen, the nitrate nitrogen content in the reaction device meets the rapid growth requirements of sulfur autotrophic denitrifying bacteria. In a specific embodiment of the present invention, the nitrate nitrogen, the first nitrate nitrogen, and the second nitrate nitrogen are preferably sodium nitrate.

[0035] In one example of the present invention, the buffer includes one or more of caustic soda, sodium carbonate, and sodium bicarbonate; and / or the second buffer includes one or more of caustic soda, sodium carbonate, and sodium bicarbonate; and / or the third buffer includes one or more of caustic soda, sodium carbonate, and sodium bicarbonate.

[0036] Specifically, the sulfur autotrophic denitrification reaction with elemental sulfur and reduced sulfur as electron donors is an acid-producing reaction, and the pH range suitable for the growth of sulfur autotrophic denitrifying bacteria is 6.5-7.8, and an alkaline buffer needs to be supplemented. In a specific embodiment of the present invention, the buffer, the first buffer, the second buffer, and the third buffer are preferably sodium carbonate.

[0037] In one embodiment of the present invention, the autotrophic denitrification filler further includes trace elements, and the trace elements include one or more configuration agents of iron, dipotassium hydrogen phosphate, and cobalt salt.

[0038] Specifically, the wastewater containing nitrate nitrogen is deficient in trace elements. By adding trace elements to the autotrophic denitrification filler, suitable nutritional conditions are provided for the growth of sulfur autotrophic denitrifying bacteria. Those skilled in the art can adjust the composition ratio of the trace elements according to actual conditions.

[0039] In one embodiment of the present invention, in S200, the activated sludge is calculated as dry sludge, accounting for 1 kg / m of the effective volume of the reaction device. 3 ~1.5Kg / m 3 .

[0040] Preferably, the activated sludge is the activated sludge from the sewage treatment plant with a higher content of reduced sulfur, followed by the residual sludge from the domestic sewage treatment plant. The activated sludge from the sewage treatment plant with a higher content of reduced sulfur has a high proportion of sulfur autotrophic bacteria. The activated sludge from the sewage treatment plant with a higher content of reduced sulfur is preferred as the bacterial strain because it has a faster start-up speed.

[0041] In one embodiment of the present invention, S300 includes controlling the reaction temperature in a control range of 20°C to 35°C.

[0042] In a specific embodiment of the present invention, the temperature control range is preferably 30°C-35°C. By controlling the reaction temperature, the temperature is controlled at 20°C-35°C, which is suitable for the growth of sulfur autotrophic denitrifying bacteria and is conducive to the rapid enrichment of sulfur autotrophic denitrifying bacteria.

[0043] In one example of the present invention, S300 includes backwashing and aeration, the backwashing includes air washing and water washing, and the backwashing time is 4 to 6 minutes.

[0044] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: aeration can promote the circulation of substances in the mixed liquid, realize sufficient contact and mixing of activated sludge and sewage, and solve the problem of packing compaction and blockage through backwashing.

[0045] In one embodiment of the present invention, the flow rate of water washing is controlled to be 15m / m 2 h, the flow rate of air washing is controlled at 30m / m 2 h, normal operating flow rate is 4m / m 2 h, the backwash cycle is 6 to 8 days.

[0046] Example 1 Preparation stage: Add soluble sodium thiosulfate into the reaction device and mix evenly through aeration to make the reduced sulfur content in the system reach 550 mg / L in terms of elemental sulfur; fill the reaction device with wastewater containing nitrate nitrogen from the previous process and add sodium nitrate to adjust the concentration of nitrate nitrogen in the system to 275 mg / L in terms of nitrogen; add 25 mg / L sodium carbonate to adjust the pH value in the system to 7-7.5 and ensure that the temperature in the system is 30°C.

[0047] Biofilm formation stage: The activated sludge from the sewage treatment plant with high reduced sulfur content in the raw water is preferred as the bacterial strain, followed by the residual sludge from the domestic sewage treatment plant. According to the effective volume of the sulfur autotrophic reactor of 1Kg / m 3 -1.5Kg / m 3After adding the bacteria, start aeration and backwashing circulation (system surface flow rate of about 8m / h) for 30 minutes to allow the bacteria to fully contact with the filler, then stop aeration, and continue to start the backwashing circulation (system surface flow rate of about 4m / h); after 3 days, perform air-water backwashing again until the effluent is basically clear, and continue the internal circulation operation; record the test data every 1.5 hours, and add the regulating component according to the ratio of the reduced sulfur concentration to the nitrate nitrogen concentration in the test data. When the concentration ratio is greater than 2:1, add the first regulating component and the third regulating component; when the concentration is less than 2:1, add the first regulating component and The second regulating component; when the concentration is equal to 2:1, the first regulating component is added; wherein the first regulating component includes sodium thiosulfate, sodium nitrate, and sodium carbonate in a mass ratio of 5:6:3; the second regulating component includes sodium thiosulfate and sodium carbonate in a mass ratio of 17:7; the third regulating component includes sodium nitrate and sodium carbonate in a mass ratio of 10:7; the reduced sulfur concentration reaches 550 mg / L, the nitrate nitrogen concentration reaches 275 mg / L, the pH value is 7-7.5, and the temperature is about 30°C; after the load rate reaches 30% of the design value, stop adding the regulating component. Table 1 is part of the detection data and addition data of Example 1.

[0048] Debugging completion stage: When the nitrate nitrogen concentration in the system drops to the emission requirement, start to continuously feed raw water, and gradually increase the water intake based on the load calculation; then, perform air-water backwashing once a week; when the load rate reaches 100%, the system debugging is completed.

[0049] Table 1 Partial test data and dosing data of Example 1 Comparative Example 1 Preparation stage: Add soluble sodium thiosulfate into the reaction device and mix evenly through aeration to make the reduced sulfur content in the system reach 500 mg / L in terms of elemental sulfur; fill the reaction device with wastewater containing nitrate nitrogen from the previous process and add sodium nitrate to adjust the concentration of nitrate nitrogen in the system to 200 mg / L~300 mg / L in terms of nitrogen; add a buffer with a slow-release effect at one time to ensure that the temperature in the system is 30°C.

[0050] Biofilm formation stage: The activated sludge from the sewage treatment plant with high reduced sulfur content in the raw water is preferred as the bacterial strain, followed by the residual sludge from the domestic sewage treatment plant. According to the effective volume of the sulfur autotrophic reactor of 1Kg / m 3 -1.5Kg / m 3After adding the bacteria, start aeration and backwashing circulation (system surface flow rate of about 8m / h) for 30 minutes to make the bacteria fully contact with the filler, then stop aeration, and continue the backwashing circulation (system surface flow rate of about 4m / h); after 3 days, backwash with air and water again until the effluent is basically clear, and continue the internal circulation operation; during this period, sodium thiosulfate and sodium nitrate are continuously added to maintain the reduced sulfur concentration of about 500mg / L, the nitrate nitrogen concentration of 200mg / L~300mg / L, and the temperature of about 30℃. When the load rate reaches 30% of the design value, stop adding reduced sulfur, use the reduced sulfur on the filler as the reducing agent, and stop adding nitrate nitrogen at the same time.

[0051] Debugging completion stage: When the nitrate nitrogen concentration in the system drops to the emission requirement, start to continuously feed raw water, and gradually increase the water intake based on the load calculation; then, perform air-water backwashing once a week; when the load rate reaches 100%, the system debugging is completed.

[0052] The difference between Example 1 and Comparative Example 1 is that Example 1 adjusts the reaction pH by adding regulating components in batches; Comparative Example 1 adds a buffer with a slow-release effect at one time, and sulfur autotrophic denitrification in Example 1 is rapidly enriched and reaches full-load operation within 15 days, while Comparative Example 1 takes 19 days to reach full load. It is reasonably inferred from the operating results that the reaction pH in Example 1 is more stable and maintained within a range of 7-7.5 suitable for the growth of sulfur autotrophic denitrifying bacteria, and the activity of sulfur autotrophic denitrifying bacteria is higher; the slow-release efficiency of the slow-release agent in Comparative Example 1 is affected by many factors, and the pH value is prone to change during the reaction, which affects the activity of sulfur autotrophic denitrifying bacteria.

[0053] Table 2 Water quality and comparison between Example 1 and Comparative Example 1 As can be seen from Table 2, compared with Comparative Example 1, Example 1 has a lower COD value, indicating that the organic matter content in the water body is low and the water quality is better; the TN value is lower, and the degree of nutrient pollution in the water body is less; the ammonia nitrogen content is lower, and the toxic effect on the ecological environment of the water body is less; the SS content is lower, and the concentration of suspended solids in the water body is low, indicating that the water quality and treatment effect are better; the TP value is lower, indicating that there is less orthophosphate in the water and the water pollution is less.

[0054] Table 3 Comparison of construction and operation of Example 1 and Comparative Example 1 (800m 3 / day scale comparison) It can be seen from Table 3 that compared with Comparative Example 1, Example 1 ensures the activity of microorganisms, improves treatment efficiency, reduces the amount of reagents used and energy consumption, and optimizes the treatment process, thereby reducing the risk of damage to the treatment equipment. Various indicators are accurately controlled, the effluent water quality meets the standards, and the ecological balance is protected, which is environmentally friendly.

[0055] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A method for rapidly culturing sulfur autotrophic denitrifying bacteria, characterized in that: include: S100, preparing an autotrophic denitrification filler, and adding the autotrophic denitrification filler into a reaction device of an autotrophic denitrification system; S200, inoculating activated sludge into the reaction device; S300, adjusting reaction conditions; In S100, the autotrophic denitrification filler includes reduced sulfur, nitrate nitrogen and sewage containing nitrate nitrogen; the reduced sulfur content is calculated as elemental sulfur, and the concentration reaches 450mg / L~550mg / L; the nitrate nitrogen content is calculated as nitrogen, and the concentration reaches 200mg / L~300mg / L; In the S300, the adjusting reaction conditions includes: S310, adding a buffer to the reaction device to adjust the initial pH of the reaction; S320, detecting the reduced sulfur content and the nitrate nitrogen content in the reaction device every 1 to 2 hours, wherein the detection result is the ratio of the reduced sulfur content to the nitrate nitrogen content, and adding a regulating component to the reaction device according to the detection result, wherein the regulating component comprises: A first regulating component, wherein the first regulating component comprises a first reduced sulfur, a first nitrate nitrogen, and a first buffer in a mass ratio of (4-7):(4-7):(1-5); A second regulating component, wherein the second regulating component comprises a second reduced sulfur and a second buffer in a mass ratio of (15-18):(6-8); A third regulating component, wherein the third regulating component comprises a second nitrate nitrogen and a third buffer in a mass ratio of (9-11):(6-8); Until the load rate reaches the designed value, stop adding the regulating component; The dosage of the first reduced sulfur and the second reduced sulfur is calculated as elemental sulfur, and the concentration of the reduced sulfur in the reaction device is controlled to reach 450 mg / L~550 mg / L. The dosage of the first nitrate nitrogen and the second nitrate nitrogen is calculated as nitrogen, and the concentration of the nitrate nitrogen in the reaction device is controlled to reach 200 mg / L~300 mg / L.

2. The method according to claim 1, characterized in that When the detection result is equal to the set ratio, adding the first regulating component to the reaction device; and / or When the detection result is greater than a set ratio, adding the first regulating component and the second regulating component to the reaction device; and / or When the detection result is less than the set ratio, the first regulating component and the third regulating component are added to the reaction device.

3. The method according to claim 1, characterized in that The reduced sulfur includes one or more of sodium thiosulfate, sodium sulfite, and hydrosulfuric acid; and / or The first reduced sulfur includes one or more of sodium thiosulfate, sodium sulfite, and hydrosulfuric acid; and / or The second reduced sulfur includes one or more of sodium thiosulfate, sodium sulfite, and hydrosulfuric acid.

4. The method according to claim 1, characterized in that: The nitrate nitrogen includes one or more of sodium nitrate and sodium nitrite; and / or The first nitrate nitrogen includes one or more of sodium nitrate and sodium nitrite; and / or The second nitrate nitrogen includes one or more of sodium nitrate and sodium nitrite.

5. The method according to claim 1, characterized in that The buffer comprises one or more of caustic soda, sodium carbonate and sodium bicarbonate; and / or The second buffer comprises one or more of caustic soda, sodium carbonate, and sodium bicarbonate; and / or The third buffer includes one or more of caustic soda, sodium carbonate, and sodium bicarbonate.

6. The method according to claim 1, characterized in that The autotrophic denitrification filler also includes trace elements, and the trace elements include one or more configuration agents of iron, dipotassium hydrogen phosphate, and cobalt salt.

7. The method according to claim 1, characterized in that In S200, the activated sludge is calculated as dry sludge, accounting for 1 kg / m of the effective volume of the reaction device. 3 ~1.5Kg / m 3 .

8. The method according to claim 1, characterized in that The step S300 includes controlling the reaction temperature in a range of 20°C to 35°C.

9. The method according to claim 1, characterized in that: The S300 includes backwashing and aeration, the backwashing includes air washing and water washing, and the backwashing time is 4 to 6 minutes.

10. The method according to claim 9, characterized in that The flow rate of the water wash is controlled to be 15m / m 2 h, the flow rate of the air wash is controlled to 30m / m 2 h, normal operating flow rate is 4m / m 2 h, the backwash cycle is 6 to 8 days.

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