350MW大型循环流化床锅炉SO_(2)和NO_(x)超低排放运行特性研究  

Study on Operation Characteristics of Ultra-low SO_(2)Emission and NO_(x)Emission of 350 MW Large Circulating Fluidized Bed Boiler

作　　者：赵强 傅斌 金燕[1] 周托 ZHAO Qiang;FU Bin;JIN Yan;ZHOU Tuo(College of Electrical and Power Engineering,Taiyuan University of Technology,030024 Taiyuan,China;Ningbo Guangyao Thermal Power Company Limited,315466 Ningbo,China;Department of Energy and Power Engineering,Tsinghua University,100084 Beijing,China)

机构地区：[1]太原理工大学电气与动力工程学院,太原030024 [2]宁波光耀热电有限公司,浙江宁波315466 [3]清华大学能源与动力工程系,北京100084

出　　处：《煤炭转化》2022年第6期80-88,共9页Coal Conversion

基　　金：山西省揭榜招标项目(20191101013);华能集团总部科技项目基础能源科技研究专项项目(HNKJ20-H50).

摘　　要：为探究循环流化床锅炉在燃用非设计煤种时脱硫脱硝系统的运行情况,并对其进行经济性分析,以某350 MW超临界循环流化床锅炉(CFB)为研究对象,采用炉内结合尾部半干法两级脱硫超低排放系统,通过实炉试验探究了在满足超低排放条件下,锅炉在燃用三种非设计煤种及三种不同负荷时炉内和尾部半干法脱硫系统的运行情况,并基于自行构建的经济性分析模型,从脱硫脱硝运行费用角度分析了不同条件下满足超低排放时机组的经济性。结果表明:在入炉煤硫含量远高于设计值的情况下,CFB锅炉采用炉内脱硫结合尾部半干法脱硫的超低SO_(2)排放技术,仍可稳定满足超低排放要求,具有显著优势,通过合理控制炉内脱硫程度(即改变锅炉出口SO_(2)质量浓度)存在最佳的系统运行经济性;煤种硫含量的变化直接影响着系统的经济运行方式,在硫质量分数分别为0.82%,1.21%,1.62%时,调整锅炉出口SO_(2)质量浓度分别为1016 mg/m^(3),1158 mg/m^(3),1259 mg/m^(3)时,系统的运行经济性最好;锅炉燃用硫质量分数为1.62%的煤种,机组在三种典型负荷(350 MW,240 MW和170 MW)下,锅炉出口SO_(2)质量浓度在1200 mg/m^(3)~1300 mg/m^(3)时,系统运行经济性最好,单位运行费用分别为0.0086元/(kW·h),0.0078元/(kW·h)和0.0085元/(kW·h);随着锅炉出口SO_(2)质量浓度增加,炉内石灰石投入量减少,进而生成的NO_(x)减少,尿素产生的运行费用减少。One 350 MW supercritical circulating fluidized bed(CFB)boiler was selected as the research object to explore the operation characteristics of desulfurization and denitrification system when burning non-designed coal.The economic analysis was also carried out.This boiler equipped with two-stage desulfurization system(in-furnace limestone desulfurization and tail flue gas desulfurization(FGD)using semi-dry method).Under the condition of meeting the ultra-low emission standard,a series of field tests were carried out to analyze the operation characteristics of this desulfurization system when burning three non-designed coal types and operating at three different loads.Meanwhile,based on the self-constructed economic analysis model,the economy of the unit meeting ultra-low emissions under different conditions was analyzed from the perspective of operational costs related to desulfurization and denitrification processes.The results show that when the sulfur content of the feeding coal is much higher than the designed value,the CFB boiler adopts the ultra-low SO_(2)emission technology,that is,in-furnace desulfurization plus semi-dry flue gas desulfurization method,can stably meet the ultra-low emission requirements and has significant advantages.By reasonably controlling the degree of desulfurization inside the furnace,namely,adjusting the SO_(2)mass concentration at the boiler outlet,a best operating economy of the whole system can be realized.The change of the sulfur content in coal directly affects the economic operation mode of the system.When the SO_(2)mass concentration at the outlet of the boiler is adjusted to 1016 mg/m^(3),1158 mg/m^(3),and 1259 mg/m^(3),the operating economy of the system is the best corresponding to the mass fraction of sulfur 0.82%,1.21%,and 1.62%,respectively.In terms of the conditions that burning coal with 1.62%sulfur content,when the SO_(2)mass concentration at the boiler outlet is in the range of 1200 mg/m^(3)-1300 mg/m^(3),the system has the best operating economy,and the operating co

关 键 词：循环流化床锅炉 SO_(2) 脱硫 超低排放 经济性分析 

分 类 号：TK221[动力工程及工程热物理—动力机械及工程] X51[环境科学与工程—环境工程]