大型燃煤机组污泥耦合发电技术研究与应用  

Research and application of sludge coupling power generation technology for large coal-fired units

作　　者：左克祥 张秀峰 ZUO Kexiang;ZHANG Xiufeng(China Energy Changzhou Power Co.ltd.,Changzhou,213033,China)

机构地区：[1]国能常州发电有限公司,江苏常州213033

出　　处：《电力科技与环保》2022年第4期317-325,共9页Electric Power Technology and Environmental Protection

基　　金：国家能源投资集团有限责任公司2030重大先导项目(GJNY2030XDXM-19-10.2)。

摘　　要：为了实现污水处理厂副产物污泥的资源化处理及提高燃燃电厂的经济效益,进行了大型燃煤机组污泥耦合发电技术试验研究,采用蒸汽转盘干化技术作为本项目污泥干化工艺路线,将80%含水率的湿污泥干化至40%含水率以下的干污泥,通过螺旋给料机输送至输煤皮带,和燃煤掺配后输送至制粉系统研磨,研磨后送至炉膛焚烧,燃烧后的灰尘经静电除尘收集、烟气经脱硝、脱硫、除尘后达到排放标准后排放。通过燃煤机组在额定工况下的污泥掺烧试验,测试了污泥掺烧比例为0%,3%,6%时对煤粉细度、灰渣产品质量、锅炉汽水参数、烟气成分、省煤器出口CO、NO_(x)浓度、炉膛壁面烟气氛围、炉膛温度、空预器漏风率、锅炉热效率的影响,并对上述指标进行对比分析。试验结果表明:(1)污泥掺煤比例为0%、3%、6%时,煤粉细度R_(90)分别为21.8%、30.4%、38%;灰渣烧失量分别为50%、56%、72.5%;再热蒸汽温度分别为568.9℃、566.9℃、558.6℃,过热减温水量分别为107.1t/h,59.2t/h,29.7t/h;省煤器出口NO_(x)浓度平均值为241mg/m^(3)、225mg/m^(3)、201mg/m^(3);(2)随着污泥掺烧比例的增加,实测锅炉热效率从94.13%降至93.95%,省煤器出口NO_(x)浓度从256mg/m^(3)降至201mg/m^(3),该工艺可以在大型燃煤机组进行实践应用及推广,掺烧污泥后,锅炉热效率较不掺烧污泥工况有所下降,高比例掺烧污泥后,炉膛温度显下降趋势,锅炉省煤器出口氮氧化物生成量有所降低,贴壁区域的还原性气体有上升趋势,有助于降低减温水量。在掺烧比为6.0%(干污泥计)工况下,总排放口烟气中汞及其化合物、镉、铊及其化合物、锑、砷、铅、铬、钴,铜、锰、镍及其化合物,二噁英、颗粒物等排放指标均满足排放要求,污泥真正实现了“资源化、能源化、无害化、减量化、稳定化”的处理。In order to realize the resource treatment of the by-product sludge of the sewage treatment plant and improve the economic benefits of the coal-fired power plant,the experimental study of the sludge coupled power generation technology of the large coal-fired unit was carried out.The steam rotary disk drying technology was used as the sludge drying process in this project.Drying the wet sludge with a moisture content of 80%to dry sludge with a moisture content of less than 40%,transport it to the coal conveyor belt through a screw feeder,and mix with coal and transport it to the pulverizing system for grinding.It is sent to the furnace for incineration,the dust after combustion is collected by electrostatic precipitator,and the flue gas is discharged after denitration,desulfurization and dust removal reach the emission standard.Through the sludge mixing combustion test of the large-scale coal-fired unit under the rated working condition(the mixing combustion ratio is 0%,3%,6%).The fineness of pulverized coal,the quality of ash and slag products,the boiler steam and water parameters,the flue gas composition,the CO and NO_(x) concentration at the outlet of the economizer,the flue gas atmosphere on the furnace wall,the furnace temperature,the air leakage rate of the air preheater boiler thermal efficiency are tested,and the above indicators are compared and analyzed.The results show that(1)when the mixing combustion ratio is 0%,3%and 6%,the pulverized coal fineness R90 is 21.8%,30.4%and 38%respectively.The ash loss on ignition is 50%,56%and 72.5%,respectively.The reheat steam temperature is 568.9℃,566.9℃,558.6℃respectively.The superheating and desuperheating water volume is 107.1t/h,59.2t/h and 29.7t/h respectively.The average NO_(x) concentration at the outlet of the economizer is 241mg/m^(3),225mg/m^(3) and 201mg/m^(3).(2)Along with the increase of mixing combustion ratio,the measured thermal efficiency of the boiler is reduced from 94.13%to 93.95%.The NO_(x) concentration at the outlet of the economizer is r

关 键 词：火力发电 燃煤机组 污泥掺烧 污泥干化 耦合发电 应用 

分 类 号：TK227.1[动力工程及工程热物理—动力机械及工程]