径流湿式静电除尘器在大型供热机组中的应用

Application of Radial Flow Wet Electrostatic Precipitator in High Capacity Thermal Power Unit

为了达到国家自2012年1月1日开始实施的GB 13223—2011《火电厂大气污染物排放标准》的排放要求(一般地区火电厂的烟尘排放浓度低于30mg/m3,重点地区低于20mg/m3),需升级改造现有除尘设备。湿式电除尘器对粉尘、液滴和重金属浓度的降低具有显著作用,同时能有效解决因浆液(产于湿法脱硫系统中)夹带而产生的石膏雨问题,是目前实现烟尘达标排放的最佳选择方案之一。因此,大唐集团决定在唐山热电300MW供热机组烟尘减排的提效工程中采用径流湿式静电除尘工艺。监测结果表明:该技术适应性强、不受煤种、烟尘特性影响,除尘和去除三氧化硫、液滴效率高,得到国家环保部门高度肯定。

According to the Emission Standard of Air Pollutants for Thermal Power Plants （GB 13223--2011） promulgated by the Ministry of Environmental Protection of the People＇s Republic of China, since Jan 1st, 2012, the dust emission concentration limit of the coal-fired boiler for the existing thermal power plant is 30mg/m3. In addition, the special dust emission concentration limit of the coal-fired boiler for the thermal power plant in the key area is also regulated to be 20mg/m3 in the Standard. In order to meet the requirements, the conventional ESP should be improved with latest technology to meet the new national standard. The wet electrostatic precipitator （WESP） can further reduce the emission of the fine particle, droplet and heavy metal in the gas flue, and prevent slurry entrainment of wet desulfurization system to solve the gypsum rain problem. WESP is one of the best solution for achieving the new emission standard. So Datang group decide to use Radial flow WESP technology in Tangshan thermal power plant 300MW unit emission reducing project. According to the test result, Radial flow WESP has high adaptability and efficiency in removing dust, droplet and SO3 in gas flue, with no respect to difference of coal type, the characteristics of gas flue. And it has been highly recognized by the State Environmental Protection Department.