丁集煤矿超低浓度瓦斯氧化供热技术应用研究

Application of ultra-low concentration gas oxidation heating technology in Dingji Coal Mine

针对丁集煤矿抽放排空超低浓度瓦斯造成的能源浪费和环境污染,介绍了超低浓度瓦斯(甲烷浓度7%以下)回收利用技术,经配气掺混后瓦斯浓度降低至1.2%送入蓄热式氧化装置,生成900℃以上高温烟气,通过烟气余热锅炉生成中温中压蒸汽供背压式汽轮发电机组发电和供热,实现热电联产。描述了应用低浓度瓦斯二次掺混输送技术解决浓瓦斯安全输送问题的方法,应用瓦斯氧化低温热风回用技术提高蓄热氧化炉热效率的方法,以及应用背压式汽轮机和后置机组合热电联产技术解决机组平稳运行与丁集煤矿热负荷波动大难适应问题的方法。最后,分析了丁集煤矿超低浓瓦斯氧化利用工程的经济和社会效益。

Aiming at the energy loss and environment pollution caused by the discharge of ultra-low concentration gas in Dingji Coal Mine,the recovery and utilization technology is introduced for ultra-low concentration gas,the methane concentration of which is below 7%.The methane concentration is reduced to 1.2%after mixing with air.It is fed to the regenerative thermal oxidizer to generate high-temperature(above 900℃)flue gas,and medium-temperature and medium-pressure steam is generated for power generation and heating of back-pressure steam turbine through flue gas waste heat boiler.The secondary mixing transportation technology of low-concentration gas is used to ensure the safe transportation of concentrated gas,the lowtemperature hot air reuse technology of gas oxidation is used to improve the thermal efficiency of regenerative thermal oxidizer furnace,and the combined heat and power technology of back-pressure turbine and post turbine is applied to stabilize the turbine operation and adapt to the great fluctuation of thermal load in Dingji Coal Mine.At last,the economic and social benefits are analyzed.