摘要
为探究铀矿井下常用的2种口罩对气溶胶粒子的过滤特性,在我国南方某铀矿山,利用APS 3321型空气动力学粒径谱仪对井下工作人员常用纱布口罩和KN95型口罩的过滤特性进行了研究。井下气溶胶监测数据显示,该铀矿井下典型作业场所PM10的质量浓度介于0.069~9.800 mg/m3,个数浓度介于173.918~2 561.600个/cm3;PM2.5的质量浓度介于0.039~0.479 mg/m3之间,个数浓度介于173.100~2 556.382个/cm3之间。口罩过滤特性试验结果表明：1）KN95型口罩和纱布口罩对PM10的平均过滤效率分别为95%和76%,对PM2.5的平均过滤效率分别为93%和61%,可见KN95型口罩过滤效率明显高于纱布口罩;2）在0.5~3.5μm粒径范围内,2种口罩对颗粒物的过滤效率均随粒径增大而增大,在3.5~10μm粒径范围内,2种口罩对不同粒径颗粒物的过滤效率均接近100%;3）无论从质量浓度还是个数浓度来看,经口罩过滤后的气溶胶粒子大多数分布在2.5μm粒径范围内,表明PM2.5是主要的气溶胶污染物。
The paper is oriented at making an exploration of the efficiency of the two kinds of frequently-used face masks in underground uranium mines for filtering the aerosol particles. For our research purpose,we have done a series of related experiments by using APS spectrometer model 3321 to trace the filtering features of gauze mask and KN95 mask in a uranium mine in China south.The results of our experiments indicate that in the actual uranium mining environment：（ 1） The filtering efficiency of the gauze mask to PM10 ranges from 61. 62% to 99. 02%,with the average filtering efficiency being 76%,whereas the filtering efficiency of the gauze mask to PM2. 5stands between 43. 70% and 80. 17%,with the average filtering efficiency being 61%. On the other hand,as to KN95 mask,the filtering efficiency to PM10 can be as high as 91. 52%-99. 92% and average value is 95%,while the filtering efficiency to PM2. 5is 89. 74%-98. 54% and average value is 93%,respectively.（ 2） And,in terms of 0. 5-3. 5 μm,the filtering efficiency of the two masks to different sizes of particles can both be expected to rise with the increase of particle size.What is more,in a range of 3. 5-10 μm,the filtration efficiency of the two masks can be close to 100%.（ 3） It can also be found that most of the minute aerosols filtrated out by the masks either in terms of mass concentration or number concentration,spread within the range of less than 2. 5 μm. What is more to be added,firstly,the filtration efficiency of gauze mask to PM10 and PM2. 5may not be steady under the mines; in contrast,the filtration efficiency of KN95 mask proves to be combatively stable and is less affected by the environmental factors. Secondly,the filtration efficiency of the gauze mask is likely significantly lower than KN95 mask both for PM10 and PM2. 5,even to the degree that the gauze mask may not be suitable for the anti-dust mask purpose for its filtration efficiencies both in the case of PM10 and in that of PM2. 5are much below the national standard values. Therefore,whereas the average filtration efficiency of KN95 mask to PM10 comes up to the national standard,its average efficiency in filtering PM2. 5is2% lower than the national standard value（ 95%）. Thirdly,the main pollutant aerosol to be filtered by the two masks is PM2. 5.Therefore,when estimating uranium mine operators＇ respiratory irradiation dose which are caused by inhaling the radioactive aerosol particles,it is important to lay stress on the effects of concentration,size distribution and chemical composition of the minute particles,especially those of PM2. 5,on the irradiation dose estimation.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2015年第5期64-68,共5页
Journal of Safety and Environment
基金
国家自然科学青年基金项目(11105069)
国家级大学生创新创业训练计划项目(201210555012)
湖南省大学生研究性学习和创新性实验计划项目(序号212)
关键词
安全工程
过滤效率
气溶胶
口罩
铀矿
safety engineering
filtration efficiency
aerosol
mask
uranium mine
