摘要
在5个不同燃煤电厂除尘器进、出口进行了现场测试，对除尘器性能以及振打时对PM10排放特征的影响进行了研究．试验系统由低压荷电捕集器（ELPI）、等速采样系统、稀释系统组成．结果表明：该试验系统可对燃煤排放的可吸入颗粒物进行在线测量，获得可吸入颗粒物的瞬时浓度．平均浓度和浓度分布，最小粒径达0.03μm，可广泛用于固定源采样；除尘器进口和出口的PM10粒数浓度均呈明显的双模态对数正态分布，峰值均分别出现在0．07～0.12μm和0．76～1．23μm；电除尘器和布袋除尘器对粗颗粒态的颗粒物去除效率均较好，最大穿透率均出现在0．1～1μm范围内，但布袋除尘器在该粒径区间的穿透率低于电除尘器，降低该区间颗粒物的穿透率有利于控制可吸入颗粒物的排放；PM10的粒数浓度主要取决于亚微米态的颗粒，针对粒数浓度而言，电除尘器对PM1和PM2.5的去除效率同样低于PM10；除尘器的运行和操作条件对PM10排放影响较大，电除尘器末电场振打清灰时，出口PM10的质量和粒数浓度均明显增加；振打时电除尘器基于粒数和质量浓度的2种除尘效率均有不同程度的下降，下降幅度最大的是PM1．
Influence of dust catchers on PM10 emission characteristics was determined experimentally at the inlet and outlet of dust catchers at five different power plants. Electrical low pressure impactor （ELPI） with a sampling system, which consisted of an isokinetic sampler probe, pre-cut cyclone, two-stage dilution system and sample line to the instruments, were used to measure in situ. Size distribution is measured on the range from 0.03μm to 10μm in aerodynamic diameter. The results show that the testing system can be used widely for sampling of particulate matters from stationary sources. Before and after all the dust catchers, the particle number size distributions display the bimodal distribution which contained the submicron mode and the coarse mode with a peak around 0.07-0.12μm and 0.76- 1 .23μm, respectively. The minimum collection efficiency of the ESP and the bag-house both appear in the particle size range of 0. 1- 1μm. In this size range, bag-house collection efficiency is higher than that of ESP. The ESP collection efficiencies of PM1 and PM2.5 based on the number concentration are also lower than that of PM10. The mass concentration of PM10 is mainly dominated by the particles which are larger than 1 μm, while the number concentration is dominated by the particles which are smaller than 0. 1 μm, Mass and number size distributions measured after ESP can be seen that mass and number concentration of PM10 will increase obviously by rapping the last electric field. Furthermore, the ESP collection efficiencies based on the number concentration and mass concentration were both decreased by ESP rapping with different degree; and the maximum drop degree was appeared in PM1.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2006年第10期1921-1927,共7页
Environmental Science
基金
国家重点基础研究发展规划(973)项目(2002CB211600)
作者简介
易红宏（1976～），女，博士研究生，主要研究方向为大气污染控制，E-mail：yhh02@mails．tsinghua．edu．cn
通讯联系人，E-mail：hjm-den@tsinghua．edu．cn
