CN-121993321-A - Energy saving and emission reduction system suitable for coal mine gas power generation

Abstract

The invention discloses an energy-saving and emission-reducing system suitable for coal mine gas power generation, which relates to the technical field of gas power generation and solves the technical problem of low energy utilization rate in the prior art when gas power generation is performed, the gas is divided into high-concentration gas and low-concentration gas by a concentration detector and is respectively input into different generator sets for power generation, high-temperature flue gas generated in the power generation process is recovered by multistage heat recovery equipment, the gas is utilized for power generation, exhaust emission can be reduced, environmental protection is facilitated, the exhaust gas generated by power generation is utilized for multiple times, the energy utilization rate is improved, and the energy waste is reduced.

Inventors

• CAI CHANGHUI
• CAI CHENXI

Assignees

• 镇投能源科技(云南)有限公司

Dates

Publication Date

20260508

Application Date

20240401

Claims (6)

1. 1. The energy-saving and emission-reducing system suitable for coal mine gas power generation is characterized by comprising a collection and purification module, a gas power generation module, a waste heat recovery module and a monitoring control module; The collecting and purifying module is used for collecting the gas from the mine, purifying and removing impurities from the gas by a pressure swing adsorption technology to obtain standard gas; The gas power generation module is used for regulating the pressure of standard gas through a pressure regulating valve to obtain pressure regulating gas, and dividing the pressure regulating gas into high-concentration gas, low-concentration gas and unavailable gas according to the concentration of the gas; The low-concentration gas is used for generating electricity through a low-concentration gas generator set, wherein the power generation equipment comprises an internal combustion engine generator set or a gas turbine generator set; The waste heat recovery module is used for collecting waste heat generated in the power generation process through a waste heat boiler, using heat recovery equipment of different grades to recover heat according to the temperature of the waste heat, and using the recovered heat for different heating equipment and power transmission equipment; The monitoring control module is used for detecting the outlet temperature, the inlet temperature, the outlet flow and the inlet flow of each heat recovery device in real time, acquiring the heat exchange efficiency of the heat recovery device according to the outlet flow, the inlet flow, the outlet temperature and the inlet temperature, acquiring the device state of the device according to the heat exchange efficiency, and replacing or maintaining the heat recovery device according to the device state, wherein the device state comprises an abnormal state and a normal state.
2. 2. An energy conservation and emission reduction system for coal mine gas power generation according to claim 1, wherein the high concentration gas is generated by a power generation device, comprising: The method comprises the steps of drying high-concentration gas, mixing the gas with air in a ratio of 1:n in a mixer to obtain combustible gas, igniting the combustible gas by an ignition system after the combustible gas enters a cylinder, generating high-temperature high-pressure gas to push a piston to do work, converting mechanical energy into kinetic energy through a crankshaft of a generator, and outputting power generation power.
3. 3. An energy conservation and emission reduction system for coal mine gas power generation according to claim 1, wherein the high concentration gas is generated by a power generation device, comprising: The method comprises the steps of drying high-concentration gas, mixing the gas with air in a ratio of 1:n in a mixer to obtain combustible gas, igniting the combustible gas by an ignition system after the combustible gas enters a cylinder, generating high-temperature high-pressure gas to push a piston to do work, converting mechanical energy into kinetic energy through a crankshaft of a generator, and outputting power generation power.
4. 4. An energy saving and emission reduction system for coal mine gas power generation according to claim 1, wherein the heat recovery using different levels of heat recovery equipment according to the waste heat temperature comprises: a1, detecting the temperature of waste heat in real time through a temperature sensor, and carrying out heat recovery on smoke generated by combustion through primary heat recovery equipment to generate high-temperature steam for power generation; a2, setting a secondary temperature threshold and a tertiary temperature threshold, judging whether the temperature of the waste heat is greater than the secondary temperature threshold, if so, continuing to use primary heat recovery equipment for heat recovery, otherwise, jumping to A3; A3, judging whether the temperature of the waste heat is greater than a three-stage temperature threshold, if yes, using a two-stage heat recovery device to recover heat, and if not, using a three-stage heat recovery device to recover heat.
5. 5. The energy saving and emission reduction system for coal mine gas power generation according to claim 1, wherein the heat exchange efficiency of the heat recovery device is obtained according to the outlet flow, the inlet flow, the outlet temperature and the inlet temperature, and the system comprises: obtaining outlet flow, inlet flow, outlet temperature and inlet temperature through a temperature detector and a mass flowmeter; The heat exchange efficiency eta is calculated by a heat formula Qin=m×c×Δtin, an input heat Qout is obtained by a heat formula Qout=c×m×Δt, a heat exchange efficiency eta is obtained by a formula eta=Qout/Qin×100%, c represents the specific heat capacity of gas, m represents the mass flow, Δtin represents the difference between the input temperature and the output temperature of the inlet of the heat recovery device, and Δt represents the difference between the input temperature and the output temperature of the outlet of the heat recovery device.
6. 6. The energy saving and emission reduction system for coal mine gas power generation according to claim 1, wherein the acquiring the equipment state of the equipment according to the heat exchange efficiency comprises: s1, extracting heat exchange efficiency and corresponding time of each heat recovery device, setting a heat exchange threshold and an extraction interval; s2, judging whether the heat exchange efficiency is smaller than a heat exchange threshold value, if yes, jumping to S3, otherwise, marking the corresponding heat recovery equipment as a normal state; S3, judging whether the heat exchange threshold value at the next moment is smaller than the heat exchange threshold value, if yes, marking the corresponding heat recovery equipment as an abnormal state, and if not, marking the corresponding heat recovery equipment as a normal state.

Description

Energy saving and emission reduction system suitable for coal mine gas power generation Technical Field The invention belongs to the technical field of gas power generation energy conservation, and particularly relates to an energy conservation and emission reduction system suitable for coal mine gas power generation. Background The coal mine is accompanied with a large amount of gas, the gas is a new energy source with high heat value and no pollution, and is usually used for generating electricity through a gas generator set, a large amount of high-temperature smoke is generated in the electricity generation process, and is discharged into the atmosphere, so that the environment is polluted, the resources are wasted greatly, the high-temperature smoke is recycled, the energy-saving effect is remarkable, and the energy-saving device has an important role in environment and energy utilization. The invention patent with the application number of CN2022102909742 discloses a method and a system for recycling heat based on coal mine gas extraction equipment, the method generates high-grade energy by extracting heat in low-grade working fluid of the gas extraction equipment, exchanges heat between the working fluid and medium water flow through a water-water heat exchanger with a shell-and-tube structure, inputs the cooled heat into a water ring vacuum pump to form a water ring again to generate negative pressure, heats the water flow through a water source heat pump unit, the method mainly exchanges heat between the working fluid and the medium water flow, has low heat retention rate and cannot be directly used for other industrial processes, The invention provides an energy-saving and emission-reducing system suitable for coal mine gas power generation, and aims to solve the technical problems. Disclosure of Invention The invention aims to at least solve one of the technical problems in the prior art, and provides an energy-saving and emission-reducing system suitable for coal mine gas power generation, which is used for solving the technical problem that the energy utilization rate is low when gas is used for power generation in the prior art. In order to achieve the aim, the first aspect of the invention provides an energy-saving and emission-reducing system suitable for coal mine gas power generation, which comprises a collection and purification module, a gas power generation module, a waste heat recovery module and a monitoring control module; The collecting and purifying module is used for collecting the gas from the mine, purifying and removing impurities from the gas by a pressure swing adsorption technology to obtain standard gas; The gas power generation module is used for regulating the pressure of standard gas through a pressure regulating valve to obtain pressure regulating gas, and dividing the pressure regulating gas into high-concentration gas, low-concentration gas and unavailable gas according to the concentration of the gas; The low-concentration gas is used for generating electricity through a low-concentration gas generator set, wherein the power generation equipment comprises an internal combustion engine generator set or a gas turbine generator set; The waste heat recovery module is used for collecting waste heat generated in the power generation process through the heat recovery equipment, using the heat recovery equipment with different grades to carry out heat recovery according to the temperature of the waste heat, and using the recovered heat for different heating equipment and power transmission equipment; The monitoring control module is used for detecting the outlet temperature, the inlet temperature, the outlet flow and the inlet flow of each heat recovery device in real time, acquiring the heat exchange efficiency of the heat recovery device according to the outlet flow, the inlet flow, the outlet temperature and the inlet temperature, acquiring the device state of the device according to the heat exchange efficiency, and replacing or maintaining the heat recovery device according to the device state, wherein the device state comprises an abnormal state and a normal state. The gas is collected and purified by the collecting and purifying module to obtain standard gas, the gas subjected to pressure regulation is divided into high-concentration gas, low-concentration gas and unusable gas according to the concentration of the gas, different power generation equipment is used for generating power for the high-concentration gas and the low-concentration gas respectively, the low-concentration gas can be effectively utilized, waste heat in the power generation process is subjected to heat recovery by heat recovery equipment of different levels, the temperature and flow of flue gas in the heat recovery equipment are monitored, the input heat and the output heat are calculated by a heat formula, the heat exchange efficiency is calculated, and the heat exchange efficiency is compared wi