To investigate the effect of high humidity of the flue gas on the sampling results of low-concentration particulate matter in coal-fired power plants with ultra-low emission technologies,the flue gas humidity is con-trolled by using a diffusion dryer to reduce vapor condensation onto the surface of the sampling tube,thereby re-ducing particulate matter (PM) transfer losses due to the PM adsorption onto a wet surface.A high-humidity flue gas simulation is performed to investigate the effect of relative humidity on PM concentration reduction.A field study is carried out at a CFB coal-fired power plant to investigate the impact of relative humidity on the PM measurement.The results show that the mass concentrations of the TSP,PM10,and PM2.5 in the power plant using conventional sampling methods are 2.73 mg/m3,2.18 mg/m3,and 1.69 mg/m3,respectively.For the sampling method with humidity control in the range of 95.1％～96.4％,the mass concentrations of TSP,PM10,and PM2.5 are 1.36～1.65 times,1.24～1.96 times,and 1.03～2.20 times higher than those at a relative humidity of 98.2％,respectively.Water-soluble ions NH4+,Cl-,SO42-are the main components of the PM in the measured power plant,accounting for about 88.3％～99.7％ of the total ions.After controlling the humidity by the diffusion drying tube,the total mass concentrations of TSP,PM10 and PM2.5 water-soluble ions collected were using traditional methods' 1.72 times,1.82 times and 1.74 times,respectively.It showes that flue gas humidity control helps to reduce the PM transfer loss due to adsorption onto the inner surface of the sampling tube,improving the efficiency of PM collection to ensure the accuracy and representativeness of the samples.
关键词
燃煤电厂/循环流化床锅炉/高湿烟气/颗粒物/水溶性离子
Key words
coal-fired power plants (CFPPs)/circulating fluidized bed (CFB) boiler/high-humidity flue gas/particulate matter (PM)/water-soluble ions
维普
万方数据