Device for degrading coal mine low-concentration gas waste gas through biofilm method and control method thereof

Abstract

The invention relates to a device for degrading coal mine low-concentration gas waste gas by a biofilm method. The device structurally comprises a microbial reactor and a gas treatment device, wherein the gas treatment device comprises a water tank and a gas tank, a wet filtration space, a moisture dissipation space and a heating space which are sequentially communicated are respectively arranged in the gas tank, a plurality of wet filtration screens are arranged in the wet filtration space, a moisture dissipation material is arranged in the moisture dissipation space, and a first heating resistance wire is arranged in the heating space; the bottom of the water tank is connected with rotary distributors through pipelines and valves; the rotary distributors are respectively positioned at the tops of the wet filtration space and the moisture dissipation space; a gas inlet pipe and a gas outlet pipe are respectively arranged on two sides of the gas tank, the gas inlet pipe is communicated with the wet filtration space, one end of the gas outlet pipe is communicated with the heating space, and the other end of the gas outlet pipe is communicated with the microbial reactor through a valve. According to the device, the stability and humidity of methane gas are controlled by utilizing the characteristic that methane oxidizing bacteria degrade methane, so that the biodegradation efficiency of low-concentration methane is improved, and the overall effect is improved.

Description

Technical Field

[0001] The present invention relates to a device for degrading low-concentration coal mine gas waste gas by a biofilm method and a control method thereof, belonging to the technical fields of coal mine safety and environmental protection. Background Art

[0002] The greenhouse effect caused by gas on the atmosphere is 20 times that of carbon dioxide, and the damage to the ozone layer is 7 times that of carbon dioxide. The method of draining low-concentration gas cannot meet the needs of production safety, and the low utilization rate of gas not only causes environmental pollution but also leads to energy waste. The traditional gas treatment technology mainly focuses on drainage. Currently, it has developed to co-mining of coal and gas. High-concentration extracted gas can be used for power generation, while low-concentration gas is still directly discharged into the atmosphere. Therefore, it is imperative to research and develop new technologies for degrading low-concentration coal mine gas waste gas.

[0003] Microbial treatment of gas is a brand-new path. On the one hand, it can fundamentally eliminate gas hidden dangers, convert methane into living cell substances or relatively safe carbon dioxide gas, especially with more obvious effects on the elimination of low-concentration gas. On the other hand, it can make methane return to the carbon cycle on the earth through living cells as a medium, reduce environmental pollution, and be more conducive to the sustainable development of the coal industry. Therefore, using microorganisms to degrade coal mine gas can greatly reduce the amount of gas discharged from coal mines into the atmosphere, which is beneficial to improving the greenhouse effect. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a device for degrading low-concentration coal mine gas waste gas by a biofilm method. This device utilizes the characteristics of methane-oxidizing bacteria to degrade methane, controls the stability and humidity of methane gas, thereby improving the efficiency of biological degradation of low-concentration methane and enhancing the overall effect. Another object of the present invention is to improve the absorption efficiency of low-concentration gas waste gas through the control of the device for degrading low-concentration coal mine gas waste gas by a biofilm method.

[0005] To solve the above problems, the specific technical solution of the present invention is as follows: A device for degrading low-concentration coal mine gas waste gas by a biofilm method includes a microbial reactor and a gas treatment device; the gas treatment device includes a water tank and a gas tank. In the gas tank, there are successively connected a wet filtration space, a moisture dispersion space, and a heating space. In the wet filtration space, there are several wet filter meshes. In the moisture dispersion space, there is moisture dispersion material. In the heating space, there is a first heating resistance wire; at the bottom of the water tank, a rotary distributor is connected through a pipeline and a valve. The rotary distributor is respectively located at the tops of the wet filtration space and the moisture dispersion space; on both sides of the gas tank, there are respectively a gas inlet pipe and a gas outlet pipe. The gas inlet pipe is communicated with the wet filtration space. One end of the gas outlet pipe is communicated with the heating space, and the other end is communicated with the microbial reactor through a valve.

[0006] The microbial reactor includes a reaction tank, a nutrient tank, and a waste liquid collection tank; biological fillers are provided inside the reaction tank; a nutrient tank is provided above the reaction tank, and the bottom of the nutrient tank is communicated with a rotary distributor through a pipeline and a valve. The rotary distributor is located above the inner cavity of the reaction tank; a waste liquid collection tank is provided below the reaction tank, and the lower end of the reaction tank is communicated with the inner cavity of the reaction tank through a pipeline and a valve. An exhaust pipe is also provided at the lower end of the reaction tank, and a valve is provided on the exhaust pipe.

[0007] The biological fillers are filled with peat soil and ceramsite. The particle size of the peat soil is 4 - 8 mm, the pH is 5.5 - 6.5, the water content is 45% - 60%, the organic matter content is > 30%, and the density is 1.2 mg / ml. The peat soil is rich in organic matters such as incompletely decomposed plant residues and partial humus, etc., to provide growth and reproduction for the bacterial liquid; the culture-completed methanotrophic bacteria liquid is placed on the surface of the fillers, and through the nutrients in the biological fillers, the methanotrophic bacteria grow and form a film on the surface of the fillers; while the diameter of the ceramsite is 3 - 5 cm.

[0008] The nutrient tank is in a funnel shape and is provided with nutrient solution inside; a second heating resistance wire is wrapped on the outer surface of the nutrient tank.

[0009] The nutrient solution contains Na + 、P + 、K + 、Fe 3+ 、Ga 2+ 、Mg 2+ .

[0010] According to the control method of the above biological membrane method for degrading low-concentration coal mine gas waste gas, it includes the following steps: 1) Firstly, the low-concentration gas waste is transported underground and enters the gas treatment device for dust removal, temperature adjustment, and humidification; 2) Calculate the amount of bacteria for culturing methanotrophic bacteria, the composition and quantity of the fillers and the nutrient solution, and then start to operate; 3) The humidified and heated low-concentration methane gas gradually passes through the microbial reactor. After a certain period of time, the microorganisms attach to the surface of the fillers, gradually grow and reproduce, and finally form a complete biological membrane, and use the methanotrophic bacteria to degrade the gas waste; 4) Control the opening frequency of the valve below the nutrient tank through an external computer to evenly spray the nutrient solution on the biological membrane to achieve the continuous growth of methanotrophic bacteria and rapidly reduce the low-concentration methane; 5) The unconsumed nutrient solution together with the metabolic wastes discharged by the methanotrophic bacteria are discharged into the waste liquid collection tank by opening the valve below the reaction tank.

[0011] The beneficial effects of the biological membrane method for degrading low-concentration coal mine gas waste gas device of the present invention with the above structure are: 1. The present invention abandons the traditional coal mine gas treatment technology and selects the biological membrane method to treat gas. Aiming at eliminating low-concentration gas from the source, a microbial reactor is designed to degrade low-concentration gas, realizing the degradation of low-concentration gas waste, which helps environmental protection and sustainable development. 2. This technology has a simple process, low implementation difficulty, low cost, high efficiency, less investment, convenient monitoring, and no pollution from the equipment itself. 3. The present invention can fundamentally eliminate gas hidden dangers, convert methane into life cell substances or relatively safe carbon dioxide gas, and has a more obvious effect on eliminating low-concentration gas. 4. The present invention enables methane to return to the carbon cycle circle on the earth through the medium of life cells, reduces environmental pollution, and is more conducive to the sustainable development of the coal industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is the overall flow chart of the biological membrane method for degrading gas waste. Among them, 1. Microbial reactor; 2. Gas treatment device; 3. Computer; 4. Rotary distributor; 11. Reaction tank; 12. Biological filler; 13. Nutrition tank; 14. Waste liquid collection tank; 15. Discharge pipe; 16. Second heating resistance wire; 21. Water tank; 22. Gas tank; 23. Wet filter screen; 24. Moisture-dispersing material; 25. First heating resistance wire; 26. Gas inlet pipe; 27. Gas outlet pipe. DETAILED DESCRIPTION OF THE INVENTION

[0013] As Figure 1 shown, a device for degrading low-concentration coal mine gas waste by the biological membrane method includes a microbial reactor 1 and a gas treatment device 2; the gas treatment device 2 includes a water tank 21 and a gas tank 22. Inside the gas tank 22, there are a wet filter space, a moisture-dispersing space, and a heating space that are connected in sequence. Inside the wet filter space, there are several wet filter screens 23. Inside the moisture-dispersing space, there is a moisture-dispersing material 24. Inside the heating space, there is a first heating resistance wire 25; at the bottom of the water tank, a rotary distributor 4 is connected through a pipeline and a valve. The rotary distributor 4 is respectively located at the top of the wet filter space and the moisture-dispersing space; on both sides of the gas tank 22, there are a gas inlet pipe 26 and a gas outlet pipe 27 respectively. The gas inlet pipe 26 is connected to the wet filter space, and one end of the gas outlet pipe 27 is connected to the heating space, and the other end is connected to the microbial reactor 1 through a valve.

[0014] The microbial reactor 1 includes a reaction tank 11, a nutrient tank 13, and a waste liquid collection tank 14; a biological filler 12 is provided inside the reaction tank 11; a nutrient tank 13 is provided above the reaction tank 11, and the bottom of the nutrient tank 13 is communicated with a rotary distributor 4 through a pipeline and a valve, and the rotary distributor 4 is located above the inner cavity of the reaction tank 11; a waste liquid collection tank 14 is provided below the reaction tank 11, and the lower end of the reaction tank 11 is communicated with the inner cavity of the reaction tank 11 through a pipeline and a valve, and a discharge pipe 15 is further provided at the lower end of the reaction tank 11, and a valve is provided on the discharge pipe 15. To achieve automatic control, the above valves can be designed as electrically controlled valves and are connected to an external computer 3 through a control circuit for control.

[0015] The biological filler 12 is filled with peat soil and ceramsite. The particle size of the peat soil is 4 - 8 mm, the pH is 5.5 - 6.5, the water content is 45% - 60%, the organic matter content is > 30%, and the density is 1.2 mg / ml. The peat soil is rich in organic matters such as incompletely decomposed plant residues and partial humus, etc., for the growth and reproduction of the bacterial liquid; the cultured methane-oxidizing bacteria liquid is placed on the surface of the filler, and through the nutrients in the biological filler, the methane-oxidizing bacteria grow and form a film on the surface of the filler; and the diameter of the ceramsite is 3 - 5 cm.

[0016] The nutrient tank 13 is in a funnel shape, and a nutrient solution is provided inside it. The nutrient solution 8 contains Na + 、P + 、K + 、Fe 3+ 、Ga 2+ 、Mg 2 + ; A second heating resistance wire 16 is wrapped on the outer surface of the nutrient tank 13.

[0017] The control method of the above biological membrane method for degrading low-concentration coal mine gas waste gas includes the following steps: 1) First, the low-concentration gas waste is transported underground and enters the gas treatment device for dust removal, temperature adjustment, and humidification; 2) Calculate the amount of bacteria for culturing methane-oxidizing bacteria, the components and quantities of the filler and the nutrient solution, and then start running; 3) The humidified and heated low-concentration methane gas gradually passes through the microbial reactor. After a certain period of time, the microorganisms adhere to the surface of the filler, gradually grow and reproduce, and finally form a complete biological membrane, and the methane-oxidizing bacteria are used to degrade the gas waste; 4) Control the opening frequency of the valve below the nutrient tank 13 through an external computer to evenly spray the nutrient solution on the biological membrane to achieve the continuous growth of methane-oxidizing bacteria and rapidly reduce the low-concentration methane; 5) The unconsumed nutrient solution together with the metabolic wastes discharged by the methane-oxidizing bacteria are discharged into the waste liquid collection tank 14 by opening the valve below the reaction tank.

Claims

1. A biofilm method for degrading low-concentration coal mine gas waste gas, characterized in that: The invention comprises a microbial reactor (1) and a gas processing device (2); wherein the gas processing device (2) comprises a water tank (21) and an air tank (22); a wet filter space, a moisture dissipation space and a heating space which are connected in sequence are respectively provided in the air tank (22); a plurality of wet filter screens (23) are provided in the wet filter space; a moisture dissipation material (24) is provided in the moisture dissipation space; and a first heating resistor (25) is provided in the heating space; a rotary distributor (4) is connected to the bottom of the water tank via a pipeline and a valve; the rotary distributor (4) is respectively located at the top of the wet filter space and the moisture dissipation space; and a gas inlet pipe (26) and a gas outlet pipe (27) are respectively provided on both sides of the air tank (22); the gas inlet pipe (26) is connected to the wet filter space; one end of the gas outlet pipe (27) is connected to the heating space, and the other end is connected to the microbial reactor (1) via a valve.

2. The biofilm method for degrading low-concentration coal mine gas waste gas according to claim 1 is characterized in that: The microbial reactor (1) comprises a reaction box (11), a nutrient tank (13) and a waste liquid collection cylinder (14); a biological filler (12) is arranged in the reaction box (11); a nutrient tank (13) is arranged above the reaction box (11); the bottom of the nutrient tank (13) is connected to a rotary distributor (4) through a pipeline and a valve; the rotary distributor (4) is located above the inner cavity of the reaction box (11); a waste liquid collection cylinder (14) is arranged below the reaction box (11); the lower end of the reaction box (11) is connected to the inner cavity of the reaction box (11) through a pipeline and a valve; a discharge pipe (15) is also arranged at the lower end of the reaction box (11); and a valve is arranged on the discharge pipe (15).

3. The biofilm method for degrading low-concentration coal mine gas waste gas according to claim 2 is characterized in that: The biological filler (12) is filled with peat soil and ceramsite. The peat soil has a particle size of 4 to 8 mm, a pH of 5.5 to 6.5, a water content of 45% to 60%, an organic matter content of more than 30%, and a density of 1.2 mg / ml. The peat soil is rich in organic matter such as incompletely decomposed plant residues and some humus, which provide a means for bacterial liquid to grow and reproduce. The cultured methane oxidizing bacteria liquid is placed on the surface of the filler. Through the nutrients in the biological filler, the methane oxidizing bacteria grow as a biofilm on the surface of the filler. The diameter of the ceramsite is 3 to 5 cm.

4. The biofilm method for degrading low-concentration coal mine gas waste gas according to claim 2 is characterized in that: The nutrient tank (13) is in the shape of a funnel and contains nutrient solution; the second heating resistance wire (16) is wrapped around the outer surface of the nutrient tank (13).

5. The biofilm method for degrading low-concentration coal mine gas waste gas according to claim 2 is characterized in that: The nutrient solution (8) contains Na + , P + , K + , Fe 3+ , Ga 2+ Mg 2+ .

6. The control method of the biofilm method for degrading low-concentration coal mine gas waste gas according to claim 3 is characterized in that The following steps are involved: 1) First, low-concentration gas waste gas is transported underground into the gas treatment device for dust removal, temperature adjustment and humidification; 2) Calculate the amount of bacteria and filler for culturing methane oxidizing bacteria, as well as the composition and quantity of the nutrient solution, and then start the operation; 3) The humidified and heated low-concentration methane gas gradually passes through the microbial reactor. After a certain period of time, the microorganisms attach to the surface of the filler, gradually grow and multiply, and finally form a complete biofilm, and use methane oxidizing bacteria to degrade the gas waste gas; 4) controlling the opening frequency of the valve below the nutrient tank (13) through an external computer so that the nutrient solution is evenly sprayed on the biofilm to achieve continuous growth of methane oxidizing bacteria and quickly reduce low-concentration methane; 5) The unconsumed nutrient solution together with the metabolic waste discharged by the methane oxidizing bacteria is discharged into the waste liquid collection tank (14) by opening the valve below the reaction box.

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