1000 MW超超临界燃煤锅炉高比例掺混生物质对炉内传热特性的影响

Effect of High Proportion Biomass Blending on Heat Transfer Characteristicin 1 000 MW Ultra Supercritical Coal FiredBoiler

燃煤耦合生物质发电是一种能够提高生物质利用率,减少火力发电厂碳排放量的有效途径。为探究东北地区产量丰富的玉米秸秆与京西无烟煤、西山贫煤、龙凤洗中煤、神华煤、义马烟煤、丰广褐煤等六种煤种在不同的掺混比例下对炉膛传热特性的影响,本研究建立了生物质掺混燃煤对炉膛传热特性影响的数学模型,并验证了其可靠性。并以某电厂1 000 MW超超临界压力锅炉为研究对象,对锅炉的传热特性进行了分析计算,研究了六种燃煤与玉米秸秆在不同的掺混比例下对炉膛烟气量、炉膛出口烟温、水冷壁传热热流、炉内火焰黑度、水冷壁平均热负荷、炉膛火焰平均温度以及理论燃烧温度的影响。研究结果表明:京西无烟煤与玉米秸秆构成的混合燃料具有最高的理论燃烧温度。受掺混后混合燃料热值的影响,随着掺混比例的增大,六种混合燃料的烟气量、水冷壁传热热流、水冷壁平均热负荷、炉膛火焰平均温度均呈现下降趋势。所做工作对于燃煤机组高比例掺混生物质耦合燃烧发电提供了理论依据。

Coal combustion coupled biomass power generation is an effective way to improve biomass utilization and reduce carbon emissions of thermal power plants.In order to explore the influence of six kinds of coal in Northeast China,such as corn stalks,Jingxi anthracite,Xishan lean coal,Longfeng Xizhong coal,Shenhua coal,Yima bituminous coal and Fengguang lignite,on the heat transfer characteristics of furnace under different mixing ratios,a mathematical model of the influence of biomass mixed with coal on heat transfer characteristics of furnace is established in this study,and is verified its reliability.Secondly,taking a 1000 MW ultra supercritical pressure boiler of a power plant as the research object,the heat transfer characteristics of the boiler were analyzed and calculated,and the effects of six kinds of mixed fuels on the furnace flue gas volume,furnace outlet flue gas temperature,water wall heat transfer flow,flame blackness in the furnace,average heat load of water wall,average furnace flame temperature and theoretical combustion temperature under different mixing ratios were analyzed.The results show that the mixed fuel composed of Jingxi anthracite and corn straw has the highest theoretical combustion temperature.Affected by the calorific value of the mixed fuel after mixing,with increase of mixing proportion,flue gas volume,heat transfer flow of water wall,average heat load of water wall and average temperature of furnace flame of the six mixed fuels show a downward trend.The work provides a theoretical basis for coal-fired power generation with high proportion of mixed biomass coupled combustion.