北京市生活垃圾焚烧厂耗能排污特征及节能减排潜力

将生活垃圾焚烧厂从整体到局部分为场站-工艺-单元三个层次,通过现场调查,获取了北京市生活垃圾焚烧设施在2009~2011年不同层次耗能排污数据。分析表明,在焚烧工艺中焚烧单元处理单位垃圾的电耗达到60.83 kW·h,余热发电单元水耗最大,尾气处理单元的电耗和水耗相对较小。不同场站在处理单位垃圾时烟气和炉渣产量比较接近,但飞灰排放差异较大,在2.92~24.78 kg/t垃圾之间。渗沥液水量年际变化较大,水质相对稳定,MBR单元对污染物的去除效果最好,但其耗电量较大,占渗沥液处理工艺总耗电量的87.55%。焚烧工艺发电最优值为423.77 kW·h/t垃圾,产生的电能除满足自身需求外,还剩余1.8×108 kW·h的电能,可用于渗沥液处理工艺或输向场站外部。每吨渗沥液处理最多可产生中水0.962 t,全北京市每年产生中水196456 t/a,使用潜力大。

Characteristics of the Energy Consumption and Pollutant Discharge and Potentials of Energy-Saving and Reducing Emission of Municipal Solid Waste Incineration in Beijing

Municipal solid waste incineration facilities are divided into the station-process-unit levels. The data of incineration facilities from 2009 to 2011 in Beijing were obtained through on-site investigations. The analysis showed that power consumption of incineration unit is 60.83 kW·h, and the water consumption of waste heat energy generation unit is highest. The power and water consumption of the exhaust gas treatment unit is relatively small. The same units at different stations discharge similar amounts of smoke and slag, but the amounts of fly ash vary between 2.92~24.78 kg/t refuse. The amount of leachate changes greatly with time, while the water quality remains relatively stable. The MBR unit is the best way to remove pollutants, but its power consumption comes up to 87.55% of the total electricity consumption of the leachate treatment process. The optimal electricity generation is 423.77 kW·h/t refuse. This electricity can not only meet their own needs, but also remain 1.8×10⁸ kW·h electricity for leachate treatment process or other stations. One ton of leachate can produce up to 0.962 ton of water, and all incineration facilities can produce 196456 tons of water per year, which is a potentially satisfied source for usage.