1 project profile:
In order to improve the safety of coal mine production, usually use a large amount of ventilation to discharge coal mine gas (called VAM Methane Ventilation, Air). Mine ventilation wind in the methane concentration is very low (generally less than 1%), large fluctuations in the concentration range, as the main fuel use has been limited, almost all coal mines did not try to recycle and treatment of mine spent the methane in the wind, and direct the its emissions into the atmosphere, the atmospheric environment caused serious pollution problems.
For coal mine ventilation air volume is huge, coal mine ventilation gas concentration in the wind is very low, the lack of air, gas concentration range, research and development of coal mine ventilation air methane utilization technology, the development of the vertical exhaust heat countercurrent oxidation device used to treatment and utilization of mine ventilation air methane and reduction for coal mine methane emissions of greenhouse gases, and the recovery of mine spent in the wind energy and make use of them.
2 development process
Our country of coal mine ventilation air methane utilization technology research started late, in recent years, domestic institutions of higher learning mechanism of ventilation air methane catalytic oxidation, thermal reverse flow oxidation were research laboratory, is not to develop a real demonstration run industrial prototype.
In 2007, the Zibo diesel engine company and the Institute of cooperation, jointly developed 800m3/h vertical exhaust gas thermal counter current oxidation test device, stable operation of the minimum gas concentration of 0.2%, can produce superheated steam. The experimental device in March 2009 through the technical appraisal of Shandong Province, think "the project of research and development of mine spent air gas thermal oxidation test device, has the advantages of high methane oxidation efficiency, stable operation, low energy consumption, reliable performance, etc., overall technology has reached the international advanced level.
In 800 m3 / h pilot study based on, the two sides jointly developed vertical 40000m3/h spent heat countercurrent oxidation device. By the end of 2008 completed industrial prototype trial, 2009 six months in the factory were simulated spent 800 m3 / h spent wind wind heat countercurrent oxidation device operation test. The experiment has reached the design target. The next step will be the development of 60000m3/h vertical heat exhaust countercurrent oxidation device for industrial prototype.
At present, this project has been applied for national patent 6, the project was listed as 2009 technical innovation project in Shandong Province, Shandong Province, a major energy-saving projects
Basic principle:
The exhaust gas thermal counter current oxidation device mainly consists of five parts: the main body of the oxidation device, the gas inlet and outlet distribution system, the heating starting system, the exhaust system, the real time measuring and controlling system.
External heat source (burner) the heat exchange medium solid oxide heating bed methane oxidation temperature, will be introduced into the mine ventilation gas oxidation device, in the unit and the heat exchange medium in the reaction zone of heat exchange, gas is heated up to gas combustion temperature, oxidation reaction occurs (combustion) and heat release. After the oxidation reaction is maintained, the external heating is stopped. A loop consists of two flow direction, which is controlled by the control system to automatically control the time and other parameters.
Industrial application:
Main technical parameters:
2 stable operation of gas concentration: 0.3% ~ 2%;
3 the methane oxidation rate greater than 97%;
The 4 can produce superheated steam, the steam pressure is larger than 1.6MPa, the temperature more than 350 DEG C, the pressure and temperature range of - 5%;
5 Import and export gas resistance loss is less than 4000Pa.
Main technical features
1 vertical structure is adopted to avoid the uneven temperature distribution caused by natural convection;
2 no catalyst is used to avoid the problem of catalyst poisoning caused by the lack of hydrogen sulfide in coal mine.
3 a variety of honeycomb ceramic combined oxidation bed structure, in order to improve the exhaust gas oxidation efficiency, ensure the stable operation of the oxidation device, and reduce the gas flow resistance, prolong the service life of the oxidation device.
4 using gas import and export distribution technology, the flow of gas flow through the flow of the flow of the flow guide, to ensure that the exhaust air into the oxidation bed.
5 external heat source selection of the burner, compared with the traditional electrical heating, can save a lot of electricity.
6 using the constant temperature heat source and the heat exchanger to produce superheated steam, so as to avoid the fluctuation of the parameters of the superheated steam, and improve the quality of steam.
7 high reliability computer monitoring system, centralized control of each subsystem of the device to carry out systematic coordination, to ensure the safe operation of the thermal counter current oxidation device.
