包气带中残油动态释放实验研究

Research on dynamic release of residual oil in unsaturated zone

通过地下水油类浓度、水位、降雨量及色质联机分析,确定了包气带中残油为水源地主要污染源之一.利用动态释放试验,模拟了河滩包气带油污土层中残油动态释放过程,探讨了不同水深及间歇进水对油类释放的影响并确定残油的污染能力.结果表明,油污土动态释放过程存在快慢两阶段,油类释放量随水头的增加而增加,合理放水应控制低流量.间歇后淋滤液流量降低,但油类浓度增加释放量增大.实验条件下,间歇24h后释放量增加2661mg(油)/kg(土),7天后增加23765mg(油)/kg(土).

The residual oil in unsaturated zone was determined to be one of the main pollution sources by analyzing hydrological and hydrogeological conditions,and organic components in groundwater,polluted and wastewater.The dynamic stimulation results indicate that a rapid phase and a slow phase exist in the release process.The release amount under continuous condition in the first day was 382 05mg(oil)/kg (soil),and 843 03mg(oil)/kg (soil) in 7 days.The average release rate in 7 days was 120.40mg (oil)/kg (soil)·day.In constrast with continuous process,the efflux through intermittent column reduced while the oil concentration increased.The increment was 26 61mg(oil)/kg(soil) in one day intermission and 237 65mg(oil)/kg(soil)in 7days.