燃煤机组耦合氢基衍生燃料发电对机组影响分析

Influence of large-scale coupled hydrogen derived fuel power generation on coal-fired units

氢基衍生燃料作为氢能大规模利用的解决方案近年受到重视。耦合氢基衍生燃料发电能大幅减少燃煤机组碳排放,有望成为今后燃煤机组碳减排的重要途径。针对某电厂300 MW等级燃煤机组进行了锅炉热力计算,分析了不同工况下耦合质量分数(0~100%)氢基衍生燃料发电对机组各个系统及运行参数等方面的影响。研究结果表明:大比例耦合氢基衍生燃料后最高可年减排CO_(2)约121.2万t;机组参数变化与氢基衍生燃料特性有关;当氢基衍生燃料热值较高时,排烟温度降低2.7~9.2℃、锅炉热效率提高0.04~0.91个百分点、烟气质量流量减少20.1~20.8个百分点;当氢基衍生燃料热值较低时,排烟温度上升2.4~26.2℃、锅炉热效率下降0.18~2.04个百分点,烟气质量流量最多增大0.4个百分点;大比例耦合氢基衍生燃料发电对原有送风、脱硝和脱硫系统影响较小,引风机需要扩容改造;需增设独立燃烧系统同时提高现场设备的防护等级,也需开发新型捕集系统降低二次有机气溶胶、甲醛、乙醛等非常规污染物的排放。

As a solution for large-scale utilization of hydrogen energy,hydrogen derived fuel has attracted much attention in recent years.Coupling hydrogen derived fuel power generation can greatly reduce carbon emissions of coal-fired units,which is expected to become an important way for coal-fired units to achieve carbon emission reduction in the future.The thermal calculation was performed on a 300 MW coal-fired unit.The influence of coupled hydrogen derived fuel power generation(mass ratios of 0-100%)on various systems and operating parameters of the unit under different working conditions were analyzed under different working conditions in this paper.The results show that the maximum annual emission reduction is about 1.212 million tons of CO_(2) after large-scale coupling of hydrogen derived fuel.The variation of unit parameters is related to the characteristics of hydrogen-based derived fuel.When the calorific value of hydrogen derived fuel is high,the exhaust temperature decreases by 2.7-9.2℃,the boiler thermal efficiency increases by 0.04-0.91 percent point,and the flue gas mass decreases by 20.1-20.8 percent point.When the calorific value of hydrogen derived fuel is low,the exhaust tempera⁃ture rises by 2.4-26.2℃,the boiler thermal efficiency decreases by 0.18-2.04 percent point,and the maximum increase of flue gas mass is 0.4%.Coupling hydrogen derived fuel has little influence on the original air supply system,denitration and desulfurization system.The induced draft fan needs to be expanded and reconstructed.It is necessary to add the independent combustion system and improve the pro⁃tection level of field equipment and develop the new capture system to reduce emissions of unconventional pollutants such as secondary or⁃ganic aerosol,formaldehyde and aldehyde.