Low-concentration gas combustible adjustment power generation system

Abstract

The invention relates to the field of energy, in particular to a low-concentration gas combustible method, which is characterized in that nitrogen in gas is separated by using a nitrogen molecular sieve, so that the content of methane in the residual part is increased. According to the invention, the concentration of methane is improved by separating nitrogen from low-concentration gas, and high-concentration gas is obtained, so that the problem that the low-concentration gas cannot be utilized is solved.

Description

Technical Field

[0001] This invention relates to the field of coal, and more specifically to gas treatment technology. Background Technology

[0002] Coalbed methane (also known as coalbed methane, whose main component is methane) is associated with coal mines. It is often found free in the pores of coal or adsorbed on the surface of coal matrix particles, and its main component is methane. During coal mining, methane can seep out in various forms.

[0003] In coal mining, gas explosions are one of the most serious dangers.

[0004] A gas explosion requires three basic conditions to occur simultaneously: first, the gas concentration must be within the explosion limit, generally 5%-16%; second, the oxygen concentration in the gas mixture must be no less than 12%; and third, there must be a high-temperature ignition source with sufficient energy, generally 650℃-750℃.

[0005] When the methane concentration is below 5%, the gas will not explode upon contact with a flame. When the methane concentration is 9.5%, oxygen and methane will react completely, and this concentration will have the greatest explosive power. When the methane concentration reaches 16% or higher, the gas will lose its explosiveness, but it will still burn when exposed to air.

[0006] To ensure coal mine safety, large amounts of air need to be introduced to expel (carry out) methane gas. However, the problem is:

[0007] First, coal mines require a very large amount of air, resulting in very high energy consumption.

[0008] Second, methane is a greenhouse gas.

[0009] Methane's greenhouse effect is 120 times that of carbon dioxide. Although methane reacts in the atmosphere to produce carbon dioxide over time, even after 20 years of emissions, the warming effect of each kilogram of methane is still 84 times that of carbon dioxide, and after 100 years, it is still 28 times that of carbon dioxide. Methane's impact on global warming is enormous. Although the concentration of methane in the atmosphere is much lower than that of carbon dioxide, its heat absorption capacity is more than 80 times that of carbon dioxide, equivalent to wrapping the Earth in a more powerful "thermal underwear," leading to an increasingly pronounced greenhouse effect. Furthermore, methane's warming potential is 21 times that of carbon dioxide; although it accounts for a relatively small proportion of greenhouse gas emissions, its impact on warming is relatively significant.

[0010] In existing literature and practical applications, in order to solve the methane problem and obtain energy, when the concentration of methane carried out by the air is greater than 8%, an internal combustion engine can be used for combustion power generation.

[0011] However, gas (methane) with a concentration below 8% is difficult to burn in an internal combustion engine.

[0012] In existing literature and practical applications, low-concentration methane is currently mostly treated using metal-catalyzed oxidation (RTO). However, this method involves high equipment construction costs and low energy recovery rates. When using RTO alone, the time to recoup the cost through power generation is generally greater than 10 years. Therefore, its practical application is very limited.

[0013] More critically, metal-catalyzed oxidation (RTO) is ineffective at treating methane concentrations below 3%. Therefore, there is an urgent need to find equipment and methods that are low-cost, highly efficient, and have a long service life for treating low-concentration methane. Summary of the Invention

[0014] The purpose of this section is to outline some aspects of the embodiments of the present invention and to briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section, as well as in the abstract and title of the present application, to avoid obscuring the purpose of this section, the abstract and title of the invention. Such simplifications or omissions shall not be used to limit the scope of the present invention.

[0015] In view of the problems existing in the prior art, the present invention is proposed.

[0016] To solve the above-mentioned technical problems, the present invention provides the following technical solution;

[0017] The low-concentration gas combustibility adjustment system is characterized by:

[0018] It includes a gas container, which is provided with a gas inlet for low-concentration methane gas to enter;

[0019] The gas container is equipped with a molecular sieve gas separation system;

[0020] Molecular sieve particles are incorporated into the molecular sieve gas separation system;

[0021] The molecular sieve particles used are those with the ability to separate nitrogen gas.

[0022] The gas container has a macromolecular gas outlet for emitting large volume gas molecules, including nitrogen, and a small molecule gas outlet for emitting small volume gas molecules, including methane and oxygen.

[0023] The small molecule gas emission port is connected to the oxidation combustion equipment.

[0024] The low-concentration methane combustible adjustment power generation system is characterized by:

[0025] It includes a gas container, which is provided with a gas inlet for low-concentration methane gas to enter;

[0026] The gas container is equipped with a molecular sieve gas separation system;

[0027] Molecular sieve particles are incorporated into the molecular sieve gas separation system;

[0028] The molecular sieve particles used are those with the ability to separate nitrogen gas.

[0029] The gas container has a macromolecular gas outlet for emitting large volume gas molecules, including nitrogen, and a small molecule gas outlet for emitting small volume gas molecules, including methane and oxygen.

[0030] The small molecule gas emission port is connected to an internal combustion engine that burns methane;

[0031] An internal combustion engine drives a power generation device to generate electricity.

[0032] In traditional technologies, because methane molecules are too small, existing molecular sieve technology cannot separate pure methane, nor can it increase the methane concentration by separating methane through molecular sieves. Therefore, traditional molecular sieve technology cannot increase the methane concentration to make low-concentration gas flammable.

[0033] In traditional technologies, besides molecular sieve technology, hollow fiber membrane separation technology is also used for gas separation. However, for hollow fiber membrane separation technology, methane and nitrogen are both "slow gases" and are difficult to separate.

[0034] Therefore, traditional techniques cannot increase the methane concentration to make low-concentration gas flammable.

[0035] This patent selects a suitable molecular sieve technology from separation technologies such as molecular sieve technology and hollow fiber membrane separation technology to achieve the desired technical effect.

[0036] This patent abandons the traditional approach of improving methane purity and creatively adopts a technical solution that retains both oxygen and methane as the two main gases while sieving out (reducing) nitrogen. Furthermore, it has found a suitable molecular sieve technology solution and equipment structure to realize this technology.

[0037] By reducing nitrogen content and increasing the proportion of methane and oxygen in the overall gas composition, the gas emitted from the small molecule gas emission outlet has a higher concentration of methane and oxygen, thus becoming combustible and supplying the fuel for internal combustion engines to generate electricity. It should be noted that the elimination of methane gas through combustion not only generates economic value through electricity generation, but also has additional economic and socio-environmental value for existing or ongoing carbon tax policies.

[0038] Compared to traditional metal catalytic oxidation (RTO) technology, it eliminates the need for a large metal catalytic oxidation (RTO) reactor, boiler, expensive screw turbine steam power generation system, and large condensate pumping system.

[0039] It has advantages such as low cost, high efficiency, and low failure rate.

[0040] The gas container is equipped with a gas inlet for low-concentration methane gas to enter, and the gas inlet is connected to at least one pressurizing device, which can be either a fan or an air compressor.

[0041] The macromolecular gas emission port is equipped with a valve, referred to as a macromolecular valve;

[0042] The small molecule gas emission port is equipped with a valve, which is called a small molecule valve;

[0043] With the macromolecular valve and small molecule valve closed, the pressurization equipment provides pressurized low-concentration methane gas, and the molecular sieve gas separation system separates out nitrogen gas.

[0044] Then, the valves for large molecules are opened to release nitrogen, and the valves for small molecules are opened to release a mixture of oxygen and methane.

[0045] The opening order of macromolecular valves and small molecule valves can be adjusted according to requirements.

[0046] Both macromolecular valves and small molecule valves are electrically controlled.

[0047] The low-concentration methane combustible adjustment power generation system is equipped with a microprocessor system;

[0048] The microprocessor system controls the macromolecular valve, small molecule valve, and pressurization equipment.

[0049] The molecular sieve particles are those that absorb oxygen and methane while passing through nitrogen.

[0050] The small molecule gas emission port is connected to the internal combustion engine via an extraction device;

[0051] The small molecule gas emission port is connected to the air inlet of the extraction device, and the air outlet of the extraction device is connected to the fuel supply port of the internal combustion engine.

[0052] In traditional molecular sieve gas separation systems, the gas adsorbed on the molecular sieve particles is a non-valued gas and can be released into the air without the need for extraction equipment.

[0053] In the design described in this patent, the traditional molecular sieve gas separation system that allows gas to be released naturally is no longer used. Instead, an extraction device is added, increasing energy consumption that is traditionally considered meaningless. However, this patent achieves unexpected technical results by adding equipment and increasing energy consumption.

[0054] First, by installing an air extraction device to pressurize the combustion chamber of the internal combustion engine, it is beneficial to maintain the combustion environment and improve combustion efficiency;

[0055] Secondly, it helps to quickly clear the oxygen and methane adsorbed on the molecular sieve particles, improve the working efficiency of the equipment, and also helps to reduce the size and cost of the equipment.

[0056] The low-concentration methane combustible adjustment power generation system is equipped with at least two gas containers, and each of the at least two gas containers is equipped with a molecular sieve gas separation system;

[0057] At least two molecular sieve gas separation systems are used to supply gas to the internal combustion engine at different times to ensure a stable gas supply connection.

[0058] The small molecule gas emission ports of at least two gas containers are connected to the gas inlet of the extraction equipment.

[0059] Gas is supplied to the extraction equipment at different times. The extraction equipment is connected to the fuel supply port of the internal combustion engine through a buffer gas tank.

[0060] The small molecule valve is connected to the air inlet of the extraction equipment, the air outlet of the extraction equipment is connected to the buffer storage tank, and the buffer storage tank is connected to the fuel supply port of the internal combustion engine.

[0061] By using a buffer gas storage tank, the following functions are achieved: first, to stabilize and balance the pressure in the combustion chamber of the internal combustion engine; second, to ensure a stable gas supply, preventing an excessive reduction in the gas supply to the combustion chamber due to a decrease in the gas emission from the gas container; and third, to mix the methane and oxygen mixtures produced at different times, thereby stabilizing the overall gas cost ratio.

[0062] The gas capacity of the buffer gas tank is between one-half and three times that of a single gas container.

[0063] Tests show that the buffer gas storage tank with the above-mentioned capacity has the characteristics of good gas mixing and gas stabilization effects while ensuring that the equipment volume is moderate.

[0064] An air compressor is preferred as the extraction equipment.

[0065] The internal combustion engine is equipped with an internal combustion engine control system, which is connected to a gas supply parameter sensor system.

[0066] The internal combustion engine control system controls the air compressor.

[0067] When the internal combustion engine control system detects that the gas supply pressure of the internal combustion engine is too low through the gas supply parameter sensor system, it increases the power of the air compressor.

[0068] The air extraction device in this patent uses an air compressor instead of a fan.

[0069] Traditionally, it is believed that fans are more likely to produce larger exhaust volumes, and for the same exhaust volume, they consume less energy. However, the design described in this patent abandons the fan and instead uses an air compressor, which is more expensive, consumes more energy, has a shorter lifespan, and produces smaller exhaust volumes. By overcoming existing technological biases and incurring higher costs, unexpected technical effects have been achieved.

[0070] The air compressor allows for a wider range of adjustments to the intake pressure inside the combustion chamber of the internal combustion engine.

[0071] First, it allows for higher pressure in the intake air of the internal combustion engine's combustion chamber, increasing the density of methane and oxygen. This improves flammability through density rather than simply improving performance through purity. This enables lower concentrations of methane to have practically meaningful power generation capabilities.

[0072] Secondly, it is easier to create negative pressure inside the gas container, which is more conducive to the venting of oxygen and methane adsorbed on the molecular sieve particles.

[0073] The air compressor is preferably an air compressor with a maximum discharge pressure greater than 0.2 MPa.

[0074] Actual tests show that sufficient thermal and power generation efficiencies can be achieved for methane gas concentrations of 3%–4%. The actual benefits far outweigh the equipment and operating costs of the air compressor.

[0075] The relationship between air compressor pressure and methane concentration is as follows: when the methane concentration at the fuel supply port of the internal combustion engine is 3% to 6%, the pressure at the high-pressure state of the air compressor outlet is 0.1 to 0.3 MPa.

[0076] The pressure at the air compressor outlet fluctuates depending on the operating state of the internal combustion engine (such as the piston's operating state). Therefore, this patent limits the pressure to 0.1 to 0.3 MPa under high pressure conditions.

[0077] The methane concentration is 3% to 6%, which is the concentration after reducing the nitrogen content.

[0078] Tests show that methane is flammable at a supply pressure of 0.1–0.3 MPa and a methane concentration of 3%–6%. This parameter adjustment is a setting that ensures moderate power consumption for the air compressor and economical power generation for the internal combustion engine.

[0079] It also includes a pneumatic drive device that operates under air pressure, the pneumatic drive device having a power air source inlet;

[0080] The macromolecular valve is connected to a pressure storage tank, which is connected to the power gas source inlet.

[0081] The pneumatic drive device has a power output structure that drives a power input structure connected to at least one of the booster devices.

[0082] The gas in the pressure storage tank drives the pneumatic drive device, which in turn provides some power to the pressurization equipment.

[0083] Pneumatically driven equipment can include screw compressors, turbines, impellers, steam turbines, shuttles, and other similar devices.

[0084] Boosting equipment can be air compressors or centrifugal fans.

[0085] The relationship between the pneumatic drive equipment and the booster equipment is that the pneumatic drive equipment receives a lower pressure power gas source from the pressure storage tank, while the booster equipment outputs a higher pressure low-concentration methane gas.

[0086] When the pressure of the power source gas tank is low but the gas volume is large, it can output a large amount of power through mechanical transformation, driving the pressurization equipment to output gas with a larger pressure.

[0087] The pressure storage tank provides the kinetic energy for the booster equipment, but this does not mean it provides all the kinetic energy. The booster equipment can be supplemented with electrical energy or other energy sources to complete its effective operation.

[0088] Preferably, the pneumatic drive device has a power output structure that drives a power input structure connected to at least one of the booster devices;

[0089] The booster equipment is also equipped with an electric motor to drive the equipment.

[0090] The booster equipment has a motor control system, which controls the connected motor;

[0091] The booster equipment is also equipped with a pressure sensor, which is connected to the signal acquisition port of the motor control system.

[0092] The booster equipment adjusts the operating status of the motor based on the pressure information collected by the pressure sensor.

[0093] The booster equipment adopts a dual power source structure. First, it can effectively reduce the power consumption of the motor. Second, it can adjust the working status of the motor in real time by adjusting the power supply of the motor, thereby making the air pressure output of the booster equipment quite stable and not affected by the air pressure fluctuation of the pressure storage tank.

[0094] This is of great significance for ensuring the stable operation of the entire system.

[0095] The exhaust port of the gas-driven pneumatic equipment is connected to the atmosphere, but not to the nitrogen storage tank.

[0096] After passing through the gas-driven pneumatic device, the gas in the pressure storage tank is no longer stored, but is directly discharged into the air.

[0097] It should be noted that the gas in the pressure storage tank is nitrogen with relatively high purity, and storing nitrogen in the storage tank is economically worthwhile.

[0098] However, the inventors of the patent took the opposite approach, abandoning the economically viable nitrogen gas and opting for direct atmospheric emission. This design not only simplified the system but also improved the overall exhaust flow, enhancing equipment efficiency and stability, thus generating greater practical economic benefits.

[0099] Molecular sieve particles can be selected to adsorb nitrogen and pass through other gases, or they can be selected to adsorb other gases and release nitrogen.

[0100] The preferred material in this patent is a PSA synthetic molecular sieve particle that adsorbs oxygen and methane and releases nitrogen.

[0101] While using PSA to synthesize molecular sieve particles reduces some separation precision, it also lowers the requirements for gas moisture content and the cleanliness of particulate matter in the gas, thereby reducing equipment costs and extending service life.

[0102] A gas purification device is installed before the gas supply port, which includes a particulate matter filter, an electrostatic adsorption filter, and a fiber filter in sequence.

[0103] First, large particles are removed, then small particles are electrostatically adsorbed, and finally, fiber filtration is added. This structure features low air resistance and relatively high filtration accuracy. Attached Figure Description

[0104] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0105] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0106] Figure 2 This is a schematic diagram of the overall structure of the present invention from another perspective. Detailed Implementation

[0107] To make the above-mentioned objectives, features and advantages of the present invention more readily understood, the specific embodiments of the present invention will be described in detail below.

[0108] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0109] To make the above-mentioned objectives, features and advantages of the present invention more readily understood, the specific embodiments of the present invention will be described in detail below.

[0110] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0111] Reference Figure 1 , Figure 2 A low-concentration methane combustibility adjustment system includes a gas container 1, which is provided with a gas supply port 11 for low-concentration methane gas to enter.

[0112] A molecular sieve gas separation system is installed inside gas container 1;

[0113] Molecular sieve particles are incorporated into the molecular sieve gas separation system;

[0114] The molecular sieve particles used are those with the ability to separate nitrogen gas.

[0115] The gas container 1 has a macromolecular gas discharge port 12 for discharging large volume gas molecules including nitrogen, and a small molecule gas discharge port 13 for discharging small volume gas molecules including methane and oxygen.

[0116] Small molecule gas emission port 13 is connected to the oxidation combustion device.

[0117] Reference Figure 1 , Figure 2 A low-concentration methane combustible adjustment power generation system includes a gas container 1, which is provided with a gas supply port 11 for low-concentration methane gas to enter.

[0118] A molecular sieve gas separation system is installed inside gas container 1;

[0119] Molecular sieve particles are incorporated into the molecular sieve gas separation system;

[0120] The molecular sieve particles used are those with the ability to separate nitrogen gas.

[0121] The gas container 1 has a macromolecular gas discharge port 12 for discharging large volume gas molecules including nitrogen, and a small molecule gas discharge port 13 for discharging small volume gas molecules including methane and oxygen.

[0122] Small molecule gas emission port 13 is connected to internal combustion engine 2 that burns methane;

[0123] The internal combustion engine 2 drives the connected power generation equipment 3 to generate electricity.

[0124] In traditional technologies, because methane molecules are too small, existing molecular sieve technology cannot separate pure methane, nor can it increase the methane concentration by separating methane through molecular sieves. Therefore, traditional molecular sieve technology cannot increase the methane concentration to make low-concentration gas flammable.

[0125] In traditional technologies, besides molecular sieve technology, hollow fiber membrane separation technology is also used for gas separation. However, for hollow fiber membrane separation technology, methane and nitrogen are both "slow gases" and are difficult to separate.

[0126] Therefore, traditional techniques cannot increase the methane concentration to make low-concentration gas flammable.

[0127] This patent selects a suitable molecular sieve technology from separation technologies such as molecular sieve technology and hollow fiber membrane separation technology to achieve the desired technical effect.

[0128] This patent abandons the traditional approach of improving methane purity and creatively adopts a technical solution that retains both oxygen and methane as the two main gases while sieving out (reducing) nitrogen. Furthermore, it has found a suitable molecular sieve technology solution and equipment structure to realize this technology.

[0129] By reducing the nitrogen content and increasing the proportion of methane and oxygen in the overall gas, the gas emitted from the small molecule gas emission port 13 has a higher concentration of methane and oxygen, thus becoming combustible and supplying the internal combustion engine 2 for power generation.

[0130] It should be noted that the combustion and elimination of methane gas not only generates economic value for electricity generation, but also has additional economic and socio-environmental value for existing or ongoing carbon tax policies.

[0131] Compared to traditional metal catalytic oxidation (RTO) technology, it eliminates the need for a large metal catalytic oxidation (RTO) reactor, boiler, expensive screw turbine steam power generation system, and large condensate pumping system.

[0132] It has advantages such as low cost, high efficiency, and low failure rate. The gas container 1 is provided with a gas supply port 11 for low-concentration methane gas to enter. The gas supply port 11 is connected to at least one pressurization device 4, which can be selected from a fan or an air compressor.

[0133] The macromolecular gas emission port 12 is equipped with a valve, which is called a macromolecular valve;

[0134] The small molecule gas emission port 13 is equipped with a valve, which is called a small molecule valve;

[0135] With the macromolecular valve and the small molecule valve closed, the booster device 4 provides pressurized low-concentration methane gas, and the molecular sieve gas separation system separates out nitrogen gas.

[0136] Then, the valves for large molecules are opened to release nitrogen, and the valves for small molecules are opened to release a mixture of oxygen and methane.

[0137] The opening order of macromolecular valves and small molecule valves can be adjusted according to requirements.

[0138] Both macromolecular valves and small molecule valves are electrically controlled.

[0139] The low-concentration methane combustible adjustment power generation system is equipped with a microprocessor system;

[0140] The microprocessor system controls the macromolecular valve, small molecule valve, and pressurization device 4.

[0141] The molecular sieve particles are those that absorb oxygen and methane while passing through nitrogen.

[0142] Small molecule gas emission port 13 is connected to internal combustion engine 2 via a gas extraction device 5;

[0143] The small molecule gas emission port 13 is connected to the air inlet of the extraction device 5, and the air outlet of the extraction device 5 is connected to the fuel supply port of the internal combustion engine 2.

[0144] In traditional molecular sieve gas separation systems, the gas adsorbed on the molecular sieve particles is a non-valuable gas and can be released into the air, so there is no need to install an extraction device.

[0145] In the design described above, this patent no longer employs the traditional molecular sieve gas separation system that allows gas to be released naturally. Instead, it adds a gas extraction device 5, increasing energy consumption that is traditionally considered meaningless. However, this patent achieves unexpected technical results by adding equipment and increasing energy consumption.

[0146] First, by setting up the exhaust device 5 to pressurize the combustion chamber of the internal combustion engine 2, it is beneficial to maintain the combustion environment and improve combustion efficiency;

[0147] Secondly, it helps to quickly clear the oxygen and methane adsorbed on the molecular sieve particles, improve the working efficiency of the equipment, and also helps to reduce the size and cost of the equipment.

[0148] The low-concentration methane combustible adjustment power generation system is equipped with at least two gas containers 1, and each of the at least two gas containers 1 is equipped with a molecular sieve gas separation system;

[0149] At least two molecular sieve gas separation systems are used to supply gas to the internal combustion engine 2 at different times to ensure a stable gas supply connection.

[0150] At least two gas containers 1 have small molecule gas emission ports 13, which are all connected to the gas inlet of the pumping device 5.

[0151] Gas is supplied to the extraction device 5 at different times. The extraction device 5 is connected to the fuel supply port of the internal combustion engine 2 via a buffer gas storage tank 6.

[0152] The small molecule valve is connected to the air inlet of the air extraction device 5, the air outlet of the air extraction device 5 is connected to the buffer storage tank 6, and the buffer storage tank 6 is connected to the fuel supply port of the internal combustion engine 2.

[0153] The buffer gas storage tank 6 serves three purposes: first, it stabilizes and balances the pressure in the combustion chamber of the internal combustion engine 2; second, it ensures stable gas supply, preventing excessive reduction in the gas supply to the combustion chamber due to a decrease in gas emissions from the gas container 1; and third, it mixes the methane and oxygen mixtures generated at different times, thus stabilizing the overall gas cost ratio.

[0154] The gas capacity of the buffer gas tank 6 is between one-half and three times the gas capacity of a single gas container 1.

[0155] Tests show that the buffer gas storage tank 6 with the above-mentioned capacity has the characteristics of good gas mixing effect and gas stabilization effect while ensuring that the equipment volume is moderate.

[0156] The preferred air extraction device 5 is an air compressor.

[0157] The internal combustion engine 2 is equipped with an internal combustion engine control system, which is connected to a gas supply parameter sensor system;

[0158] The internal combustion engine control system controls the air compressor.

[0159] When the internal combustion engine control system detects that the gas supply pressure of internal combustion engine 2 is too low through the gas supply parameter sensor system, the power of the air compressor is increased.

[0160] The air extraction device 5 in this patent uses an air compressor instead of a fan.

[0161] Traditionally, it is believed that fans are more likely to produce larger exhaust volumes, and for the same exhaust volume, they consume less energy. However, the design described in this patent abandons the fan and instead uses an air compressor, which is more expensive, consumes more energy, has a shorter lifespan, and produces smaller exhaust volumes. By overcoming existing technological biases and incurring higher costs, unexpected technical effects have been achieved.

[0162] The intake pressure in the combustion chamber of the internal combustion engine 2 was adjusted to a wider range using an air compressor.

[0163] First, it allows for higher pressure in the intake air of the combustion chamber of the internal combustion engine, increasing the density of methane and oxygen. This improves flammability through density rather than simply improving performance through purity. This enables lower concentrations of methane to have practically meaningful power generation capabilities.

[0164] Secondly, it is easier to generate negative pressure inside the gas container 1, which is more conducive to the venting of oxygen and methane adsorbed on the molecular sieve particles.

[0165] The air compressor is preferably an air compressor with a maximum discharge pressure greater than 0.2 MPa.

[0166] Actual tests show that sufficient thermal and power generation efficiencies can be achieved for methane gas concentrations of 3%–4%. The actual benefits far outweigh the equipment and operating costs of the air compressor.

[0167] The relationship between air compressor pressure and methane concentration is as follows: when the methane concentration at the fuel supply port of internal combustion engine 2 is 3% to 6%, the pressure at the high-pressure state of the air compressor outlet is 0.1 to 0.3 MPa.

[0168] The pressure at the air compressor outlet will fluctuate with the operating state of the internal combustion engine 2 (such as the piston operating state), therefore this patent limits the pressure to 0.1 to 0.3 MPa under high pressure.

[0169] The methane concentration is 3% to 6%, which is the concentration after reducing the nitrogen content.

[0170] Tests show that methane is flammable at a supply pressure of 0.1–0.3 MPa and a methane concentration of 3%–6%. This parameter adjustment is a setting that ensures moderate power consumption of the air compressor and practical economic benefits for the internal combustion engine in generating electricity.

[0171] It also includes a pneumatic drive device that operates under air pressure, the pneumatic drive device having a power air source inlet;

[0172] The macromolecular valve is connected to a pressure storage tank, which is connected to the power gas source inlet.

[0173] The pneumatic drive device has a power output structure that drives a power input structure connected to at least one of the booster devices 4;

[0174] The gas in the pressure storage tank drives the pneumatic drive device, which in turn provides some power to the booster device 4.

[0175] Pneumatically driven equipment can include screw compressors, turbines, impellers, steam turbines, shuttles, and other similar devices.

[0176] The booster device 4 can be an air compressor or a centrifugal fan.

[0177] The relationship between the pneumatic drive device and the booster device 4 is such that the power gas source pressure input from the pressure storage tank to the pneumatic drive device is relatively low, while the output pressure of the low-concentration methane gas from the booster device 4 is relatively high.

[0178] When the pressure of the power source gas tank is low but the gas volume is large, it can output a large amount of power through mechanical transformation, driving the booster device 4 to output gas with a larger pressure.

[0179] The pressure storage tank provides the kinetic energy for the booster device 4, but this does not mean that it provides all the kinetic energy. The booster device 4 can be supplemented with electrical energy or other energy sources to complete its effective operation.

[0180] Preferably, the pneumatic drive device has a power output structure, which drives a power input structure connected to at least one of the booster devices 4;

[0181] The booster unit 4 is also equipped with an electric motor to drive the equipment.

[0182] The booster unit 4 has a motor control system, which controls the connected motor.

[0183] The booster device 4 is also equipped with a pressure sensor, which is connected to the signal acquisition port of the motor control system.

[0184] The booster device 4 adjusts the working status of the motor based on the pressure information collected by the pressure sensor.

[0185] The booster device 4 adopts a dual power source structure. First, it can effectively reduce the power consumption of the motor. Second, it can adjust the working status of the motor in real time by adjusting the power supply of the motor, thereby making the air pressure output of the booster device 4 quite stable and not affected by the air pressure fluctuation of the pressure storage tank.

[0186] This is of great significance for ensuring the stable operation of the entire system.

[0187] The exhaust port of the gas-driven pneumatic equipment is connected to the atmosphere, but not to the nitrogen storage tank.

[0188] After passing through the gas-driven pneumatic device, the gas in the pressure storage tank is no longer stored, but is directly discharged into the air.

[0189] It should be noted that the gas in the pressure storage tank is nitrogen with relatively high purity, and storing nitrogen in the storage tank is economically worthwhile.

[0190] However, the inventors of the patent took the opposite approach, abandoning the economically viable nitrogen gas and opting for direct atmospheric emission. This design not only simplified the system but also improved the overall exhaust flow, enhancing equipment efficiency and stability, thus generating greater practical economic benefits.

[0191] Molecular sieve particles can be selected to adsorb nitrogen and pass through other gases, or they can be selected to adsorb other gases and release nitrogen.

[0192] The preferred material in this patent is a PSA synthetic molecular sieve particle that adsorbs oxygen and methane and releases nitrogen.

[0193] While using PSA to synthesize molecular sieve particles reduces some separation precision, it also lowers the requirements for gas moisture content and the cleanliness of particulate matter in the gas, thereby reducing equipment costs and extending service life.

[0194] A gas purification device is installed before the gas supply port 11, which includes a particulate matter filter, an electrostatic adsorption filter, and a fiber filter in sequence.

[0195] First, large particles are removed, then small particles are electrostatically adsorbed, and finally, fiber filtration is added. This structure features low air resistance and relatively high filtration accuracy.

[0196] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A low-concentration methane combustible adjustment power generation system, characterized in that, It includes a gas container 1, which is provided with a gas inlet 11 for low-concentration methane gas to enter; A molecular sieve gas separation system is installed inside gas container 1; Molecular sieve particles are incorporated into the molecular sieve gas separation system; The molecular sieve particles used are those with the ability to separate nitrogen gas. The gas container 1 has a macromolecular gas discharge port 12 for discharging large volume gas molecules including nitrogen, and a small molecule gas discharge port 13 for discharging small volume gas molecules including methane and oxygen. Small molecule gas emission port 13 is connected to internal combustion engine 2 that burns methane; The internal combustion engine 2 drives the connected power generation equipment 3 to generate electricity; By reducing the nitrogen content and increasing the proportion of methane and oxygen in the overall gas, the gas emitted from the small molecule gas emission port 13 has a higher concentration of methane and oxygen, thus becoming combustible and supplying the internal combustion engine 2 for power generation.

2. The low-concentration methane combustibility adjustment power generation system according to claim 1, characterized in that, The gas container 1 is provided with a gas supply port 11 for low-concentration methane gas to enter. The gas supply port 11 is connected to at least one pressurizing device 4, which can be either a fan or an air compressor. The macromolecular gas emission port 12 is equipped with a valve, which is called a macromolecular valve; The small molecule gas emission port 13 is equipped with a valve, which is called a small molecule valve; With the macromolecular valve and the small molecule valve closed, the booster device 4 provides pressurized low-concentration methane gas, and the molecular sieve gas separation system separates out nitrogen gas. Then, the valves for large molecules are opened to release nitrogen, and the valves for small molecules are opened to release a mixture of oxygen and methane.

3. The low-concentration methane combustibility adjustment power generation system according to claim 2, characterized in that, Both macromolecular valves and small molecule valves are electrically controlled. The low-concentration methane combustible adjustment power generation system is equipped with a microprocessor system; The microprocessor system controls and connects the macromolecular valve, the small molecule valve, and the pressurizing device 4. The molecular sieve particles are those that absorb oxygen and methane while passing through nitrogen. Small molecule gas emission port 13 is connected to internal combustion engine 2 via a gas extraction device 5; The small molecule gas emission port 13 is connected to the air inlet of the extraction device 5, and the air outlet of the extraction device 5 is connected to the fuel supply port of the internal combustion engine 2.

4. The low-concentration methane combustibility adjustment power generation system according to claim 2, characterized in that, The system is equipped with at least two gas containers 1, and each of the at least two gas containers 1 is equipped with a molecular sieve gas separation system. At least two molecular sieve gas separation systems supply gas to the internal combustion engine 2 at different times to ensure a stable gas supply connection. At least two small molecule gas emission ports 13 of the gas containers 1 are connected to the gas inlet of the pumping device 5; Gas is supplied to the extraction device 5 at different times. The extraction device 5 is connected to the fuel supply port of the internal combustion engine 2 through a buffer gas storage tank 6. The small molecule valve is connected to the air inlet of the air extraction device 5, the air outlet of the air extraction device 5 is connected to the buffer storage tank 6, and the buffer storage tank 6 is connected to the fuel supply port of the internal combustion engine 2.

5. The low-concentration methane combustibility adjustment power generation system according to claim 4, characterized in that, The gas capacity of the buffer gas tank 6 is between one-half and three times the gas capacity of a single gas container 1.

6. The low-concentration methane combustibility adjustment power generation system according to claim 4, characterized in that, The extraction device 5 is an air compressor; The internal combustion engine 2 is equipped with an internal combustion engine control system, which is connected to a gas supply parameter sensor system; The internal combustion engine control system controls the air compressor. When the internal combustion engine control system detects that the gas supply pressure of internal combustion engine 2 is too low through the gas supply parameter sensor system, the power of the air compressor is increased.

7. The low-concentration methane combustibility adjustment power generation system according to claim 1, characterized in that, It also includes a pneumatic drive device that operates under air pressure, the pneumatic drive device having a power air source inlet; The macromolecular valve is connected to a pressure storage tank, which is connected to the power gas source inlet. The pneumatic drive device has a power output structure that drives a power input structure connected to at least one of the booster devices 4; The gas in the pressure storage tank drives the pneumatic drive device, thereby providing part of the power to the booster device 4; The relationship between the pneumatic drive device and the booster device 4 is such that the power gas source pressure input from the pressure storage tank to the pneumatic drive device is relatively low, while the output pressure of the low-concentration methane gas from the booster device 4 is relatively high.

8. The low-concentration methane combustibility adjustment power generation system according to claim 7, characterized in that, The pneumatic drive device has a power output structure that drives a power input structure connected to at least one of the booster devices 4; The booster unit 4 is also equipped with an electric motor to drive the equipment. The booster unit 4 has a motor control system, which controls the connected motor. The booster device 4 is also equipped with a pressure sensor, which is connected to the signal acquisition port of the motor control system.

9. The low-concentration methane combustibility adjustment power generation system according to claim 1, characterized in that, PSA-synthesized molecular sieve particles selectively adsorb oxygen and methane, releasing nitrogen.

10. The low-concentration methane combustibility regulation power generation system according to any one of claims 1 to 9, characterized in that, A gas purification device is installed before the gas supply port 11, which includes a particulate matter filter, an electrostatic adsorption filter, and a fiber filter in sequence.

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