Sulfide internal circulation autotrophic biological nitrogen removal technology

Abstract

A sulfide internal circulation autotrophic biological nitrogen removal technology comprises a sewage pool, a desulfurization tower and a sulfur autotrophic nitrogen removal bioreactor, the desulfurization tower is connected with the sewage pool and the sulfur autotrophic nitrogen removal bioreactor through a waste gas pipeline and an absorption liquid pipeline, and hydrogen sulfide-containing waste gas generated by the sewage pool is absorbed by alkali liquor in the desulfurization tower and then is discharged into the absorption liquid pipeline. The absorption liquid is input into a sulfur autotrophic nitrogen removal bioreactor as a nutrient solution for a sulfur autotrophic biological nitrogen removal process; a first filler layer, a first spraying layer, a second filler layer and a second spraying layer are respectively arranged on the desulfurizing tower from bottom to top, and spraying assemblies are mounted in the first spraying layer and the second spraying layer. After a large amount of hydrogen sulfide generated during anaerobic-stage operation of a sewage plant of an enterprise is absorbed by alkali liquor in the desulfurization tower, the absorption liquid is input into the sulfur autotrophic nitrogen removal bioreactor as a nutrient solution for a sulfur autotrophic biological nitrogen removal process, so that internal circulation autotrophic nitrogen removal of sulfide is realized, generation of hazardous wastes is reduced, and the aim of recycling wastes is fulfilled.

Description

Technical Field

[0001] The invention belongs to the technical field of autotrophic denitrification using sulfide internal circulation in sewage treatment industry, and specifically relates to a technical process for autotrophic biological denitrification using sulfide internal circulation. Background Art

[0002] Existing sewage treatment plants produce a large amount of secondary pollutants such as hydrogen sulfide during the anaerobic stage. The most common treatment methods for hydrogen sulfide are dry desulfurization, wet desulfurization or biological desulfurization. Most of the byproduct sulfides produced by the reaction are treated as hazardous waste, but in fact, sulfur can be used as a nutrient in biological treatment of sewage. At the same time, the existing sulfur autotrophic denitrification process often uses sulfur as a reducing agent in microbial purification treatment to reduce nitrates or nitrites in wastewater into nitrogen gas, thereby reducing the total nitrogen in the wastewater.

[0003] The above two processes have the following disadvantages:

[0004] 1. The process is complicated.

[0005] 2. The by-products of the desulfurization process are treated as hazardous waste, wasting resources.

[0006] 3. Wastewater and waste gas treatment are two independent processes with high investment and operating costs and great difficulty in joint control.

[0007] 4. Sulfur autotrophic denitrification requires the addition of new sulfide as nutrients. Summary of the invention

[0008] In view of the above, the present invention provides a sulfide internal circulation autotrophic biological denitrification technology process to solve the problems raised in the above background technology.

[0009] A technical solution provided by the present invention is: a sulfide internal circulation autotrophic biological denitrification technology process, comprising a sewage pool, a desulfurization tower, and a sulfur autotrophic denitrification bioreactor, wherein the desulfurization tower is respectively connected to the sewage pool and the sulfur autotrophic denitrification bioreactor through a waste gas pipeline and an absorption liquid pipeline, and the waste gas containing hydrogen sulfide generated in the sewage pool is absorbed by the alkaline solution in the desulfurization tower, and the absorption liquid is input into the sulfur autotrophic denitrification bioreactor as a nutrient solution to carry out the sulfur autotrophic denitrification process; the waste gas pipeline of the sewage pool is connected to the lower end of the desulfurization tower, and a negative pressure fan is installed on the waste gas pipeline to send the hydrogen sulfide waste gas into the desulfurization tower from bottom to top; the desulfurization tower is respectively provided with a first packing layer, a first spraying layer, a second packing layer and a second spraying layer from bottom to top, and the first spraying layer and the second spraying layer are respectively provided with a negative pressure fan from top to bottom. A spray assembly for spraying alkali solution at the bottom, when the hydrogen sulfide waste gas is sent from bottom to top into the desulfurization tower to undergo acid-base neutralization reaction with the alkali solution, the generated sulfide absorption liquid will fall into the bottom of the desulfurization tower and be regularly discharged into the wastewater tank to be treated, and the treated hydrogen sulfide waste gas is discharged in compliance with the standards through a discharge cylinder or other means; a wastewater tank for storing wastewater containing nitrate and nitrite is arranged at the lower end of the sulfur autotrophic denitrification bioreactor, and the wastewater tank to be treated is connected to the wastewater tank through an absorption liquid pipeline, which is used to transport the sulfide absorption liquid as a nutrient solution to the wastewater tank, and use the sulfide absorption liquid as a reducing agent to reduce the nitrate and nitrite contained in the wastewater to nitrogen gas in an anoxic environment, thereby reducing the total nitrogen in the wastewater; an air distribution area, a biological filler area and a water outlet area are respectively arranged at the upper end of the sulfur autotrophic denitrification bioreactor.

[0010] Preferably, the gas distribution zone is provided with a discharge pipe and a feed pipe, and the discharge pipe is equipped with a discharge valve for discharging nitrogen; the feed pipe is equipped with a feed valve for inputting carbonate, bicarbonate and carbon dioxide as inorganic carbon sources, or supplementing sodium sulfide, sodium thiosulfate or elemental sulfur as an electron donor.

[0011] Preferably, the biological filler zone includes coral stone and suspended ball fillers.

[0012] Preferably, the water outlet area includes a water outlet pipe, a water outlet pump, and a water outlet valve. The water outlet pipe is connected between the water outlet pump and the wastewater tank. The water outlet valve is installed on the water outlet pipe. The treated nitrate and nitrite wastewater is discharged in compliance with the standards through the water outlet pipe or other means.

[0013] Preferably, the spray assembly includes a water pump, a spray pipeline and a nozzle. A reaction tank for storing alkali solution is installed on one side of the desulfurization tower, and the water pump is installed in the reaction tank. The spray pipeline and the nozzle are distributed in the first spray layer and the second spray layer. The water outlet end of the water pump is connected to the spray pipeline to realize top-down alkali solution spraying.

[0014] Preferably, the first filler layer and the second filler layer include sawdust and modified peat.

[0015] Preferably, a sewage outlet is provided at the bottom of the desulfurization tower and the sulfur autotrophic denitrification bioreactor, and the sewage outlet is connected to a sewage pipe.

[0016] In view of the shortcomings of the existing process, the patent of the present invention provides a new sulfide internal circulation autotrophic biological denitrification technology process. After the large amount of hydrogen sulfide generated during the anaerobic stage of the enterprise sewage treatment plant is absorbed by the alkaline solution in the desulfurization tower, the absorbed liquid is input into the sulfur autotrophic denitrification bioreactor as a nutrient solution for the sulfur autotrophic biological denitrification process. The advantages of the desulfurization process and the sulfur autotrophic denitrification process are combined to avoid the disadvantages, so that the sulfide internal circulation autotrophic denitrification is achieved, which reduces the generation of hazardous waste and achieves the purpose of waste recycling. It not only treats the hydrogen sulfide in the exhaust gas, but also uses sulfide as a nutrient agent for the second time, which can also ensure that the sulfur autotrophic biological denitrification operation has a good effect. From the operation point of view, it not only simplifies the process, but also reduces the generation of secondary pollutants. While treating the exhaust gas, the sewage is also treated. There is no need to add additional sewage treatment equipment, which reduces the operating cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a process flow chart of the present invention.

[0018] Figure 2 It is a structural diagram of the sewage pool and desulfurization tower.

[0019] Figure 3 It is a structural schematic diagram of the sulfur autotrophic denitrification bioreactor.

[0020] In the figure, 1, desulfurization tower; 101, first packing layer; 102, first spray layer; 103, second packing layer; 104, second spray layer; 2, sewage pool; 3, sulfur autotrophic denitrification bioreactor; 301, gas distribution area; 302, biological packing area; 303, water outlet area; 4, waste gas pipeline; 401, negative pressure fan; 5, absorption liquid pipeline; 6, wastewater tank to be treated; 7, wastewater tank; 8, reaction tank; 9, water pump; 901, spray pipeline; 10, sewage pipeline; 11, discharge pipeline; 12, feed pipeline; 13, water outlet pump. DETAILED DESCRIPTION

[0021] The present invention is further described below in conjunction with the accompanying drawings and some implementation modes.

[0022] exist Figure 1-Figure 3A sulfide internal circulation autotrophic biological denitrification technology process is provided, comprising a sewage pool 2, a desulfurization tower 1, and a sulfur autotrophic denitrification bioreactor 3. The desulfurization tower 1 is connected to the sewage pool 2 and the sulfur autotrophic denitrification bioreactor 3 respectively through a waste gas pipeline 4 and an absorption liquid pipeline 5. After the waste gas containing hydrogen sulfide generated by the sewage pool 2 is absorbed by the alkaline solution in the desulfurization tower 1, the absorption liquid is input into the sulfur autotrophic denitrification bioreactor 3 as a nutrient solution to carry out the sulfur autotrophic biological denitrification process.

[0023] In this embodiment, the exhaust pipe 4 of the sewage pool 2 is connected to the lower end of the desulfurization tower 1, and a negative pressure fan 401 is installed on the exhaust pipe 4 to send the hydrogen sulfide waste gas into the desulfurization tower 1 from bottom to top; the desulfurization tower 1 is respectively provided with a first packing layer 101, a first spray layer 102, a second packing layer 103 and a second spray layer 104 from bottom to top, and the first spray layer 102 and the second spray layer 104 are respectively installed with spray components for spraying alkali solution from top to bottom. When the hydrogen sulfide waste gas is sent from bottom to top into the desulfurization tower 1 to react with the alkali solution with acid-base neutralization, the generated sulfide absorption liquid will fall into the bottom of the desulfurization tower 1 and be regularly discharged into the wastewater tank 6 to be treated, and the treated hydrogen sulfide waste gas passes through the discharge cylinder Or other means to meet the emission standards; under the suction action of the negative pressure fan 401, a large amount of hydrogen sulfide waste gas generated during the anaerobic stage of the enterprise's sewage treatment plant is sent from bottom to top into the desulfurization tower 1 through the waste gas pipe 4, and the first spray layer 102 and the second spray layer 104 in the desulfurization tower 1 are sprayed with alkali solution from top to bottom through the water pump 9, the spray pipeline 901 and the nozzle, and the alkali solution in the desulfurization tower 1 is used to carry out acid-base neutralization reaction with the waste gas, and the generated sulfide absorption liquid will fall into the bottom of the desulfurization tower 1 and be regularly discharged into the wastewater tank 6 to be treated, and the hydrogen sulfide waste gas after multi-stage treatment by the first packing layer 101, the first spray layer 102, the second packing layer 103 and the second spray layer 104 is discharged through the discharge cylinder or other means to meet the emission standards.

[0024] In this embodiment, a wastewater tank 7 for storing wastewater containing nitrate and nitrite is provided at the lower end of the sulfur autotrophic denitrification bioreactor 3. The wastewater tank 6 to be treated is connected to the wastewater tank 7 by an absorption liquid pipeline 5, which is used to transport the sulfide absorption liquid as a nutrient solution to the wastewater tank 7; the absorption liquid in the wastewater tank 6 to be treated is input into the sulfur autotrophic denitrification bioreactor 3 through the absorption liquid pipeline 5 as a nutrient solution for sulfur autotrophic biological denitrification process utilization. By using the sulfide absorption liquid as a reducing agent, the nitrate and nitrite contained in the wastewater are reduced to nitrogen gas in an anaerobic environment, thereby reducing the total nitrogen in the wastewater. The advantages of the desulfurization process and the sulfur autotrophic denitrification process are combined, and the disadvantages are avoided, so that the sulfide internal circulation autotrophic denitrification is achieved, the generation of hazardous waste is reduced, and the purpose of waste recycling is achieved.

[0025] In this embodiment, the upper end of the sulfur autotrophic denitrification bioreactor 3 is respectively provided with a gas distribution area 301, a biological filler area 302 and a water outlet area 303; the gas distribution area 301 is provided with a discharge pipe 11 and a feed pipe 12, and the discharge pipe 11 is equipped with a discharge valve for discharging nitrogen; the feed pipe 12 is equipped with a feed valve for inputting carbonate, bicarbonate and carbon dioxide as inorganic carbon sources, or supplementing sodium sulfide, sodium thiosulfate or elemental sulfur as an electron donor; the sulfur autotrophic denitrification bioreactor 3 utilizes sulfur autotrophic biological denitrification technology, uses sulfide as a reducing agent, and utilizes inorganic carbon sources and electron donors in an anaerobic environment to efficiently convert nitrate nitrogen and nitrite nitrogen into nitrogen, which has significant environmental benefits and broad application prospects.

[0026] In this embodiment, the biological filler area 302 includes coral stone and suspended ball filler; the water outlet area 303 includes a water outlet pipe, a water outlet pump 13, and a water outlet valve. The water outlet pipe is connected between the water outlet pump 13 and the wastewater tank 7, and the water outlet valve is installed on the water outlet pipe; it is used to absorb nitrate and nitrite contained in the wastewater, so that the treated nitrate and nitrite wastewater can be discharged through the water outlet pipe or other channels to meet the standards.

[0027] In this embodiment, the spray assembly includes a water pump 9, a spray pipeline 901 and a nozzle. A reaction tank 8 for storing alkali solution is installed on one side of the desulfurization tower 1. The water pump 9 is installed in the reaction tank 8. The spray pipeline 901 and the nozzle are distributed in the first spray layer 102 and the second spray layer 104. The water outlet end of the water pump 9 is connected to the spray pipeline 901 to realize top-down alkali solution spraying; the first spray layer 102 and the second spray layer 104 in the desulfurization tower 1 are sprayed with alkali solution from top to bottom through the water pump 9, the spray pipeline 901 and the nozzle, and the alkali solution in the desulfurization tower 1 is used to carry out acid-base neutralization reaction with the exhaust gas.

[0028] In this embodiment, the first filler layer 101 and the second filler layer 103 include sawdust and modified peat; the moist, porous and active microbial filler layer adsorbs pollutants in the exhaust gas, and the specialized microorganisms attached to the inside and outside of the filler absorb and degrade the pollutants, decomposing them into simple non-toxic and harmless inorganic substances such as SO42-, NO3-, CO2, H2O, etc., so that the hydrogen sulfide exhaust gas after multi-stage treatment can be discharged through the emission tube or other means to meet the emission standards, which has significant environmental benefits.

[0029] In this embodiment, a sewage outlet is provided at the bottom of the desulfurization tower 1 and the sulfur autotrophic denitrification bioreactor 3, and the sewage outlet is connected to a sewage pipe 10; waste materials in the wastewater tank and the wastewater tank 7 after a long period of work are discharged through the sewage pipe 10, which is helpful for the maintenance of the desulfurization tower 1 and the sulfur autotrophic denitrification bioreactor 3.

[0030] In the specific implementation of the present invention: under the suction effect of the negative pressure fan 401, a large amount of hydrogen sulfide waste gas generated during the anaerobic stage of the enterprise sewage treatment plant is sent from bottom to top into the desulfurization tower 1 through the waste gas pipeline 4, and the first spray layer 102 and the second spray layer 104 in the desulfurization tower 1 are sprayed with alkali solution from top to bottom through the water pump 9, the spray pipeline 901 and the nozzle, and the alkali solution in the desulfurization tower 1 is used to neutralize the acid and base with the waste gas, and the generated sulfide absorption liquid will fall into the bottom of the desulfurization tower 1 and be regularly discharged into the wastewater tank 6 to be treated, and the first packing layer 101, the first spray layer 102, the second packing layer 104 are sprayed with alkali solution from top to bottom. 03 and the second spray layer 104 after multi-stage treatment, the hydrogen sulfide waste gas is discharged through the discharge tube or other means in compliance with the standards; the absorption liquid in the wastewater tank 6 to be treated is input into the sulfur autotrophic denitrification bioreactor 3 as a nutrient solution through the absorption liquid pipeline 5 for sulfur autotrophic biological denitrification process. By using the sulfide absorption liquid as a reducing agent, the nitrate and nitrite contained in the wastewater are reduced to nitrogen gas in an anaerobic environment, thereby reducing the total nitrogen in the wastewater. The advantages of the desulfurization process and the sulfur autotrophic denitrification process are combined to avoid the disadvantages, so that the sulfide internal circulation autotrophic denitrification is achieved, the generation of hazardous waste is reduced, and the purpose of waste recycling is achieved.

[0031] It is worth noting that: in the description of the present invention, the meaning of "multiple" is two or more than two, unless otherwise clearly and specifically defined. In the present invention, unless otherwise clearly specified and defined, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection. The circuits described in the present invention are all commonly used circuits in the art, and other related components are all existing commonly used components. For ordinary technicians in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0032] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes that fall within the meaning and scope of the elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. A sulfide internal circulation autotrophic biological denitrification technology process, characterized by: It includes a sewage pool, a desulfurization tower, and a sulfur autotrophic denitrification bioreactor. The desulfurization tower is connected to the sewage pool and the sulfur autotrophic denitrification bioreactor through a waste gas pipeline and an absorption liquid pipeline. The waste gas containing hydrogen sulfide generated in the sewage pool is absorbed by the alkaline solution in the desulfurization tower, and the absorption liquid is input into the sulfur autotrophic denitrification bioreactor as a nutrient solution to carry out the sulfur autotrophic biological denitrification process. The waste gas pipeline of the sewage pool is connected to the lower end of the desulfurization tower, and a negative pressure fan is installed on the waste gas pipeline to send the hydrogen sulfide waste gas into the desulfurization tower from bottom to top; The desulfurization tower is provided with a first packing layer, a first spray layer, a second packing layer and a second spray layer from bottom to top, respectively. The first spray layer and the second spray layer are respectively installed with spray components for spraying alkali solution from top to bottom. When the hydrogen sulfide waste gas is sent into the desulfurization tower from bottom to top to undergo acid-base neutralization reaction with the alkali solution, the generated sulfide absorption liquid will fall into the bottom of the desulfurization tower and be regularly discharged into the wastewater tank to be treated. The treated hydrogen sulfide waste gas is discharged through a discharge cylinder or other means to meet the standards; A wastewater tank for storing wastewater containing nitrate and nitrite is provided at the lower end of the sulfur autotrophic denitrification bioreactor. The wastewater tank to be treated is connected to the wastewater tank via an absorption liquid pipeline, which is used to transport the sulfide absorption liquid as a nutrient solution into the wastewater tank, and use the sulfide absorption liquid as a reducing agent to reduce the nitrate and nitrite contained in the wastewater into nitrogen gas in an anaerobic environment, thereby reducing the total nitrogen in the wastewater. The upper end of the sulfur autotrophic denitrification bioreactor is respectively provided with a gas distribution area, a biological filler area and a water outlet area.

2. The sulfide internal circulation autotrophic biological denitrification technology process according to claim 1 is characterized by: The gas distribution area is provided with a discharge pipe and a feed pipe. The discharge pipe is provided with a discharge valve for discharging nitrogen; the feed pipe is provided with a feed valve for inputting carbonate, bicarbonate and carbon dioxide as inorganic carbon sources, or supplementing sodium sulfide, sodium thiosulfate or elemental sulfur as an electron donor.

3. The sulfide internal circulation autotrophic biological denitrification technology process according to claim 1 is characterized by: The biological filler area includes coral stone and suspended ball fillers.

4. The sulfide internal circulation autotrophic biological denitrification technology process according to claim 1 is characterized by: The outlet area includes an outlet pipe, an outlet pump, and an outlet valve. The outlet pipe is connected between the outlet pump and the wastewater tank. The outlet valve is installed on the outlet pipe. The treated nitrate and nitrite wastewater is discharged in compliance with the standards through the outlet pipe or other means.

5. The sulfide internal circulation autotrophic biological denitrification technology process according to claim 1 is characterized by: The spray assembly includes a water pump, a spray pipeline and a nozzle. A reaction tank for storing alkali solution is installed on one side of the desulfurization tower. The water pump is installed in the reaction tank. The spray pipeline and the nozzle are distributed in the first spray layer and the second spray layer. The water outlet end of the water pump is connected to the spray pipeline to realize top-down alkali solution spraying.

6. The sulfide internal circulation autotrophic biological denitrification technology process according to claim 1 is characterized by: The first filler layer and the second filler layer include sawdust and modified peat.

7. The sulfide internal circulation autotrophic biological denitrification technology process according to claim 1 is characterized by: The bottom of the desulfurization tower and the sulfur autotrophic denitrification bioreactor is provided with a sewage outlet, and the sewage outlet is connected to a sewage pipe.

Images