重力沉降作用下的采样管路颗粒物损失

为了研究烟尘采样系统的系统误差,采用重力沉降理论对颗粒物在水平直管段内的穿透率进行了理论计算,并以此方法为基础估算了在线监测系统水平直管段由于重力沉降造成的测量误差。结果表明,水平直采样管内的颗粒物损失会随着粒径增大、停留时间增长而显著增多;当颗粒物采样系统为烟气外抽式时,水平直管内颗粒物重力沉降会造成采样系统误差,超低排放的达标测量值应小于10 mg/m~3。以一台600 MW火电机组为例,估算出由于采样系统水平直管内颗粒物重力沉降造成的年烟尘误排量约为15.5 t。

Effect of gravitational deposition on particle tube loss of sampling system

The effect of gravitational deposition on the transporting loss usually caused a system error in sampling tube according to the gravitational deposition theory.Thus,the measurement error of in-situ horizontal straight sampling tube was theoretically studied in this paper.Results show that with the particle diameter and the residence time increase,the transporting loss increases significantly.The online monitor standard of the ultra-low emission of particle should be less than 10 mg./m3 when considering the transporting loss of the horizontal sampling tube in the in-situ external particle extraction sampling system.In addition,the extra particulate matter emission of a 600 MW coal-fired power plant is about 15.5 t per year due to the effect of the transporting loss on the horizontal straight sampling tube measurement.