多孔介质中柴油的挥发行为

Volatilization behaviors of diesel oil in porous media

根据石油污染场地挥发性物质的污染特点,以采集的砂样和土样为下垫面,将柴油均匀覆盖在下垫面表面,然后采用差减法确定含油土柱中石油的挥发量,并系统研究风速和挥发容器尺度对石油挥发速率的影响,以及挥发过程中柴油组分的变化。研究结果表明,柴油在粗砂、细砂和亚黏土中挥发速率依次递增。风速的增大可使粗砂、细砂和亚黏土中柴油挥发速率提高1~2倍,二项式可描述柴油挥发速率与风速的关系。柴油中低碳组分首先挥发,且风对低碳组分的挥发影响明显,而对高碳组分nC16的挥发作用不大。柴油挥发速率系数随挥发容器尺度增大而增加,且两者呈线性正相关。

Based on the pollution characteristics of vaporizing materials in oil-contaminated field,coarse sand,fine sand and loam were collected and loaded in columns respectively firstly.Then diesel oil was spilled on porous media surface.The mass loss of oil was determined by weighing the column before and after oil volatilization on an electronic balance.The effects of wind speed,volatilization vessel diameter on oil volatilization rate and the content change of different oil components were studied.The results show that the volatilization rates of diesel oil on coarse sand,fine sand and loam increase in sequence,they go up with wind speed especially for light components and are 1—2 times higher than that in no wind condition.They are boundary-layer-regulated slightly.A binomial equation can express the relationship between volatilization coefficient and wind speed well.The effect of wind speed on the vaporization of low carbon components is obvious,while on nC16 it can be negligible.The volatilization coefficient of diesel oil increases linearly with the volatilization vessel diameter.