A rapid cultivation method for sulfur autotrophic denitrifying bacteria

Abstract

The present invention provides a rapid cultivation method for sulfur autotrophic denitrifying bacteria, comprising: S100, preparing autotrophic denitrifying fillers; S200, inoculating activated sludge into a reaction device; S300, adjusting reaction conditions; in S100, the autotrophic denitrifying fillers include reduced sulfur, nitrate nitrogen, and sewage containing nitrate nitrogen; the content of reduced sulfur is calculated as elemental sulfur, and the concentration reaches 450 mg / L to 550 mg / L, and the content of nitrate nitrogen is calculated as nitrogen, and the concentration reaches 200 mg / L to 300 mg / L; in S300, adjusting the reaction conditions includes: S310, adding a buffer to the reaction device to adjust the initial pH of the reaction; S320, detecting the content of reduced sulfur and nitrate nitrogen in the reaction device every 1 to 2 hours, and the detection result is the ratio of the content of reduced sulfur to the content of nitrate nitrogen, and adding an adjustment component to the reaction device according to the detection result. The technical problem solved by the present invention is to accurately control the pH of the reaction while solving the rapid cultivation of sulfur autotrophic denitrifying bacteria, reduce unnecessary waste, and realize the rational utilization of resources.

Description

Technical Field

[0001] The present 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 using reduced sulfur such as elemental sulfur, sulfite, hydrosulfuric acid, hydrogen sulfide, etc. as electron donors and energy sources, and under the action of microorganisms, reducing nitrate or nitrite to nitrogen, so as to achieve the purpose of nitrogen removal, without adding organic carbon, and at the same time oxidizing the reduced sulfur to sulfate.

[0003] In the prior art, the proportion of sulfur autotrophic denitrifying bacteria in the conventional activated sludge treatment system is relatively low, and they have strict requirements for the living environment and are extremely easy to lose. Therefore, the sulfur autotrophic denitrification process generally has the problem of a long startup period. In recent years, solving the problems 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 various improvement measures, there is an issue 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 value will affect the sulfur autotrophic denitrification reaction.

[0004] The Chinese patent document with the publication number of CN115304159B discloses a broad-spectrum adaptable autotrophic denitrification filter material and its preparation method, including a denitrification main functional active component and an auxiliary component with slow-release neutralization ability. In the form of a two-component system, a neutralizing agent component with a slow-release function is added to the reaction system to eliminate hydrogen ions generated during the denitrification process. From the input of reactants until the reaction is completed, the auxiliary component exists throughout the reaction process. The control of pH is reflected in the slow-release rate, but the slow-release rate is affected by various factors and has instability, and cannot accurately adjust the change of pH value.

[0005] By detecting the change of pH value in real time to adjust the reaction pH, due to the certain hysteresis between the measured value of pH by the pH meter and its actual value, it is not easy to control the dosage of the buffer when adjusting the reaction pH. And the reaction is carried out in a reactor with a large volume. After the pH buffer is added, it takes a certain time to complete the neutralization reaction, which not only causes great difficulties in pH value control, but also is prone to over-adjustment, resulting in a large waste of acid and alkali neutralizing agents, and even causing the drainage pH value to exceed the standard. Therefore, while solving the rapid cultivation of sulfur autotrophic denitrifying bacteria, it is necessary to accurately control the pH of the reaction, reduce unnecessary waste, and achieve the rational utilization of resources. Summary of the Invention

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

[0007] To solve the above problems, the present invention provides a rapid cultivation method for sulfur autotrophic denitrifying bacteria, including: S100, preparing autotrophic denitrifying fillers, and adding the autotrophic denitrifying fillers into the reaction device of the autotrophic denitrifying system; S200, inoculating activated sludge into the reaction device; S300, adjusting the reaction conditions; in S100, the autotrophic denitrifying fillers include reduced sulfur, nitrate nitrogen, and sewage containing nitrate nitrogen; the content of reduced sulfur is calculated as elemental sulfur, and the concentration reaches 450 mg / L to 550 mg / L; the content of nitrate nitrogen is calculated as nitrogen, and the concentration reaches 200 mg / L to 300 mg / L; in S300, adjusting the reaction conditions includes: S310, adding a buffer into the reaction device to adjust the initial pH of the reaction; S320, detecting the content of reduced sulfur and nitrate nitrogen in the reaction device every 1 to 2 hours, and the detection result is the ratio of the content of reduced sulfur to the content of nitrate nitrogen. According to the detection result, adding a regulating component into the reaction device, and the regulating component includes: 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 loading rate reaches the design 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 reduced sulfur in the reaction device is controlled to reach 450 mg / L to 550 mg / L, and the dosage of the first nitrate nitrogen and the second nitrate nitrogen is calculated as nitrogen, and the concentration of nitrate nitrogen in the reaction device is controlled to reach 200 mg / L to 300 mg / L.

[0008] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: By preparing sulfur autotrophic denitrification fillers, where the autotrophic denitrification fillers include reduced sulfur, nitrate nitrogen, and sewage containing nitrate nitrogen; the concentration of reduced sulfur in the reaction device is made to reach 450 mg / L to 550 mg / L, and the concentration of nitrate nitrogen reaches 200 mg / L to 300 mg / L; providing sufficient nutrient substrates for the growth of sulfur autotrophic denitrifying bacteria. In this application, the method of adding regulatory components in batches is used to maintain stable growth conditions for cultivating sulfur autotrophic denitrifying bacteria. Considering the actual situation of rapid cultivation of sulfur autotrophic denitrifying bacteria, since the reaction is carried out in a relatively large reaction device, after the pH buffer is added, there is a certain lag between the pH measured by the pH meter and its actual value. Therefore, when adjusting the reaction pH, it is not easy to control the dosage of the buffer, and the acid-base neutralization process shows a serious non-linear characteristic, making the chemical reaction relatively slow. This not only causes great difficulties in pH value control but also easily leads to over-adjustment, resulting in a large waste of acid and base neutralizing agents and even causing the drainage pH value to exceed the standard. The sulfur autotrophic denitrification reaction with elemental sulfur and reduced sulfur as electron donors is an acid-producing reaction. Using reduced sulfur and nitrate nitrogen related to pH value changes to set regulatory components, while adjusting the elemental sulfur concentration and nitrogen concentration, the reaction pH is adjusted. After 1 to 2 hours, the concentration of reduced sulfur and nitrate nitrogen in the reaction device decreases and exceeds the lower limit of the set concentration range. At this time, regulatory components are added to adjust the concentration of reduced sulfur and nitrate nitrogen in the reaction device. The first regulatory component includes first reduced sulfur, first nitrate nitrogen, and first buffer, with a mass ratio of (4 - 7):(4 - 7):(1 - 5); the second regulatory component includes second reduced sulfur and second buffer, with a mass ratio of (15 - 18):(6 - 8); the third regulatory component includes second nitrate nitrogen and third buffer, with a mass ratio of (9 - 11):(6 - 8); According to the detection results, regulatory components are added to adjust the concentration of reduced sulfur and nitrate nitrogen to the set concentration range. At the same time, the regulatory components also contain a corresponding proportion of buffer, which can maintain the stability of pH during this period.

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

[0010] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: Let the ratio be the ratio of the preset reduced sulfur concentration to 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. Add the first regulating component, and the ratio of the reduced sulfur concentration to the nitrate nitrogen concentration in the first regulating component is equal to the set ratio. As the first regulating component is added, the reduced sulfur concentration and the nitrate nitrogen concentration return to the initial state. At the same time, the first buffer is added according to the proportion to supplement the alkalinity consumed in the reaction device. When the detection result is less than the set ratio, the loss of the reduced sulfur content in the reaction device is excessive. While adding the first regulating component, it is also necessary to add the second regulating component to make up for the excessive loss of the reduced sulfur. The first buffer and the second buffer are added according to the proportion to supplement the alkalinity consumed in the reaction device. When the detection result is greater than the set ratio, the loss of the nitrate nitrogen content in the reaction device is excessive. While adding the first regulating component, it is also necessary to add the third regulating component to make up for the excessive loss of the nitrate nitrogen. The first buffer and the third buffer are added according to the proportion to supplement the alkalinity consumed in the reaction device.

[0011] In an example 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 effects achieved by adopting this technical solution are as follows: Considering the actual situation of cultivating sulfur autotrophic denitrifying bacteria, the reduced sulfur during the startup and operation processes 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 the startup period, resulting in slow growth of sulfur autotrophic bacteria. By adding easily soluble reduced sulfur, sufficient nutrient substrates are provided in the reaction device.

[0013] In an 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 effects achieved by adopting this technical solution: Considering the actual situation of sulfur autotrophic denitrifying bacteria cultivation, the nitrate nitrogen during the startup and operation processes is the nitrate nitrogen of the pretreatment process of its system, and its concentration often fails to reach the concentration required for the rapid growth of sulfur autotrophic bacteria. For projects with relatively low nitrate nitrogen concentration in the raw water, the nitrate nitrogen concentration in the influent 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 can meet the requirements for the rapid growth 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 effects achieved by adopting this technical solution: The sulfur autotrophic denitrification reaction using elemental sulfur and reduced sulfur as electron donors is an acid-producing reaction. The suitable pH value range for the growth of sulfur autotrophic denitrifying bacteria is 6.5 - 7.8, and an alkaline buffer needs to be supplemented.

[0017] In one example of the present invention, the autotrophic denitrification filler further includes trace elements, and the trace elements include one or several of iron, dipotassium hydrogen phosphate, and cobalt salts for preparing agents.

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

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

[0020] Compared with the prior art, the technical effects achieved by adopting this technical solution: Considering the actual situation of sulfur autotrophic denitrifying bacteria cultivation, the conventional inoculation of strains is generally the activated sludge from domestic sewage treatment plants. However, the concentration of reduced sulfur in the sewage of domestic sewage treatment plants is very low, so the proportion of sulfur autotrophic bacteria is relatively low, and the startup speed using the sludge from domestic sewage treatment plants as the strain is slow. By preferentially selecting the activated sludge from sewage treatment plants with relatively high reduced sulfur content in the raw water as the strain, and the activated sludge, calculated as dry sludge, accounts for 1 Kg / m 3 ~1.5 Kg / m 3 , a certain amount of startup strains are provided in the reaction device.

[0021] In one example of the present invention, S300 includes controlling the reaction temperature, and the control range is 20°C to 35°C.

[0022] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: By controlling the reaction temperature and keeping the temperature within the range of 20°C to 35°C, it 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 prior art, the technical effects achieved by adopting this technical solution are as follows: Aeration can promote the cyclic flow of substances in the mixed liquor, realize the full contact and mixing of activated sludge and sewage, and the problem of packing plate clogging can be solved through backwashing.

[0025] In one example of the present invention, the flow rate of water washing is controlled at 15 m / m 2 h, the flow rate of air washing is controlled at 30 m / m 2 h, the normal operation flow rate is 4 m / m 2 h, and the backwashing period is 6 to 8 days. Specific Embodiments

[0026] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following detailed description of the specific embodiments of the present invention is provided in conjunction with the accompanying drawings.

[0027] The present invention provides a rapid cultivation method for sulfur autotrophic denitrifying bacteria, including: S100, preparing autotrophic denitrifying fillers and adding the autotrophic denitrifying fillers into the reaction device of the autotrophic denitrifying system; S200, inoculating activated sludge into the reaction device; S300, adjusting the reaction conditions; in S100, the autotrophic denitrifying fillers include reduced sulfur, nitrate nitrogen and sewage containing nitrate nitrogen; the content of reduced sulfur is calculated as elemental sulfur, and the concentration reaches 450 mg / L to 550 mg / L; the content of nitrate nitrogen is calculated as nitrogen, and the concentration reaches 200 mg / L to 300 mg / L; in S300, adjusting the reaction conditions includes: S310, adding a buffer into the reaction device to adjust the initial pH of the reaction; S320, detecting the content of reduced sulfur and the content of nitrate nitrogen in the reaction device every 1 to 2 hours, and the detection result is the ratio of the content of reduced sulfur to the content of nitrate nitrogen. According to the detection result, adding an adjustment component into the reaction device, and the adjustment component includes: a first adjustment component, the first adjustment 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 adjustment component, the second adjustment component includes a second reduced sulfur and a second buffer, and the mass ratio is (15-18):(6-8); a third adjustment component, the third adjustment component includes a second nitrate nitrogen and a third buffer, and the mass ratio is (9-11):(6-8); until the loading rate reaches the design value, stop adding the adjustment component; the dosage of the first reduced sulfur and the second reduced sulfur is calculated as elemental sulfur, and the concentration of reduced sulfur in the reaction device is controlled to reach 450 mg / L to 550 mg / L, and the dosage of the first nitrate nitrogen and the second nitrate nitrogen is calculated as nitrogen, and the concentration of nitrate nitrogen in the reaction device is controlled to reach 200 mg / L to 300 mg / L.

[0028] Specifically, by preparing sulfur autotrophic denitrification fillers, where the autotrophic denitrification fillers include reduced sulfur, nitrate nitrogen, and sewage containing nitrate nitrogen; making the concentration of reduced sulfur in the reaction device reach 450 mg / L - 550 mg / L and the concentration of nitrate nitrogen reach 200 mg / L - 300 mg / L; providing sufficient nutrient substrates for the growth of sulfur autotrophic denitrifying bacteria. In this application, the method of adding regulatory components in batches is used to maintain stable growth conditions for culturing sulfur autotrophic denitrifying bacteria. Considering the actual situation of rapid cultivation of sulfur autotrophic denitrifying bacteria, since the reaction is carried out in a relatively large reaction device, after the pH buffer is added, there is a certain lag between the pH value measured by the pH meter and its actual value. Therefore, when adjusting the reaction pH, it is not easy to control the dosage of the buffer, and the acid-base neutralization process shows severe non-linear characteristics, making the chemical reaction relatively slow. This not only causes great difficulties in pH value control but also easily leads to over-adjustment, resulting in a large waste of acid and base neutralizing agents and even causing the drainage pH value to exceed the standard. The sulfur autotrophic denitrification reaction with elemental sulfur and reduced sulfur as electron donors is an acid-producing reaction. Using reduced sulfur and nitrate nitrogen related to pH value changes to set regulatory components, while adjusting the concentration of reduced sulfur and nitrate nitrogen, the reaction pH is adjusted. After 1 - 2 hours, the concentration of reduced sulfur and nitrate nitrogen in the reaction device decreases and exceeds the lower limit of the set concentration range. At this time, regulatory components are added to adjust the concentration of reduced sulfur and nitrate nitrogen in the reaction device. The first regulatory component includes first reduced sulfur, first nitrate nitrogen, and first buffer, with a mass ratio of (4 - 7):(4 - 7):(1 - 5); the second regulatory component includes second reduced sulfur and second buffer, with a mass ratio of (15 - 18):(6 - 8); the third regulatory component includes second nitrate nitrogen and third buffer, with a mass ratio of (9 - 11):(6 - 8); according to the detection results, regulatory components are added to adjust the concentration of reduced sulfur and nitrate nitrogen to the set concentration range. At the same time, the regulatory components also contain a corresponding proportion of buffer, which can maintain the stability of pH during this period.

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

[0030] Specifically, in a specific embodiment, the set ratio is the ratio of the preset reduced sulfur concentration to the preset nitrate nitrogen concentration in the reaction device, which is 2:1. 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. Add the first adjustment component, where the mass ratio of the first adjustment component is 5:6:3; the ratio of the reduced sulfur concentration to the nitrate nitrogen concentration in the first adjustment component is equal to the set ratio. As the first adjustment component is added, the reduced sulfur concentration and the nitrate nitrogen concentration return to the initial state. 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 less than the set ratio, the loss of the reduced sulfur content in the reaction device is excessive. When adding the first adjustment component, it is also necessary to add the second adjustment component to make up for the excessive loss of the reduced sulfur. The mass ratio of the first adjustment component is 5:6:3, and the mass ratio of the second adjustment component is 17:7. The first buffer and the second buffer are 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 loss of the nitrate nitrogen content in the reaction device is excessive. When adding the first adjustment component, it is also necessary to add the third adjustment component to make up for the excessive loss of the nitrate nitrogen. The mass ratio of the first adjustment component is 5:6:3, and the mass ratio of the third adjustment component is 10:7. The first buffer and the third buffer are added according to the ratio to supplement the alkalinity consumed in the reaction device.

[0031] In an example of the present invention, the reduced sulfur includes one or more of sodium thiosulfate, sodium sulfite, and hydrogen sulfide; and / or the first reduced sulfur includes one or more of sodium thiosulfate, sodium sulfite, and hydrogen sulfide; and / or the second reduced sulfur includes one or more of sodium thiosulfate, sodium sulfite, and hydrogen sulfide.

[0032] Specifically, in combination with the actual situation of the cultivation of sulfur autotrophic denitrifying bacteria, the reduced sulfur during the start-up and operation process 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 the start-up period, resulting in slow growth of sulfur autotrophic bacteria. By adding easily soluble reduced sulfur, there is enough nutrient substrate in the reaction device. 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 an 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 sulfur autotrophic denitrifying bacteria cultivation, the nitrate nitrogen in the start-up and operation processes is the nitrate nitrogen of the pre-treatment process of its system, and its concentration often fails to reach the concentration required for the rapid growth of sulfur autotrophic bacteria. For projects with relatively low nitrate nitrogen concentration in the raw water, the nitrate nitrogen concentration in the influent of the sulfur autotrophic reaction device is often low, and it 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 can meet 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 an 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 using elemental sulfur and reduced sulfur as electron donors is an acid-producing reaction. The suitable pH value range 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 an example of the present invention, the autotrophic denitrification filler further includes trace elements, and the trace elements include one or more of iron, dipotassium hydrogen phosphate, and cobalt salts for preparing the agent.

[0038] Specifically, the trace elements in the nitrate nitrogen-containing sewage are lacking. By adding trace elements to the autotrophic denitrification filler, suitable nutrient conditions can be provided for the growth of sulfur autotrophic denitrifying bacteria, and those skilled in the art can adjust the composition ratio of the trace elements according to the actual situation.

[0039] In an example of the present invention, in S200, the activated sludge is calculated as dry sludge and accounts for 1 Kg / m of the effective volume of the reaction device. 3 ~1.5 Kg / m 3 。

[0040] Preferably, the activated sludge is preferably the activated sludge of a sewage treatment plant with a relatively high reduced sulfur content, followed by the excess sludge of a domestic sewage treatment plant. The proportion of sulfur autotrophic bacteria in the activated sludge of a sewage treatment plant with a relatively high reduced sulfur content is high. It is preferred to use the activated sludge of a sewage treatment plant with a relatively high reduced sulfur content as the strain, and the start-up speed is relatively fast.

[0041] In an example of the present invention, S300 includes controlling the reaction temperature, and the control range is 20°C to 35°C.

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

[0043] In an 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 prior art, the technical effects achieved by adopting this technical solution are as follows: Aeration can promote the cyclic flow of substances in the mixed liquor, enabling full contact and mixing of the activated sludge and sewage. The problem of packing plate clogging can be solved through backwashing.

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

[0046] Example 1

[0047] Preparation stage: Add soluble sodium thiosulfate to the reaction device and mix it evenly through aeration, so that the content of reduced sulfur in the system, calculated as elemental sulfur, reaches 550 mg / L; fill the reaction device with the sewage containing nitrate nitrogen from the previous process and add sodium nitrate to adjust the concentration of nitrate nitrogen in the system, calculated as nitrogen, to reach 275 mg / L; add 25 mg / L of sodium carbonate to adjust the pH value of the system to 7 - 7.5, and ensure that the temperature in the system is 30°C.

[0048] Biofilm formation stage: First, select the activated sludge from a sewage treatment plant with a relatively high content of reduced sulfur in the raw water as the strain, and secondly, select the excess sludge from a domestic sewage treatment plant. According to the effective volume of the sulfur autotrophic reactor, 1 Kg / m 3 -1.5 Kg / 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.

[0049] 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.

[0050] Table 1 Partial test data and dosing data of Example 1

[0051]

[0052] Comparative Example 1

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] Table 2 Water quality and comparison between Example 1 and Comparative Example 1

[0058]

[0059] 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.

[0060] Table 3 Comparison of construction and operation of Example 1 and Comparative Example 1 (800m 3 / day scale comparison)

[0061]

[0062] As can be seen from Table 3, compared with Comparative Example 1, in Example 1, by reasonably controlling the indicators, the activity of microorganisms was ensured, the treatment efficiency was improved, the dosage of chemicals and energy consumption were reduced, and the treatment process was optimized, reducing the risk of damage to the treatment equipment; each indicator was accurately controlled, the effluent quality met the standards, the ecological balance was protected, and it was environmentally friendly.

[0063] 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 should 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); 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 less than the set ratio, adding the first regulating component and the second 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 third regulating component to the reaction device; 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 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.

3. 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.

4. 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.

5. 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.

6. 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 .

7. 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.

8. 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.

9. The method according to claim 8, 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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