摘要
采用土柱渗流试验，模拟人工回灌过程中含水层的物理堵塞过程。通过测定回灌过程中含水介质渗透系数的时一空变化，系统分析和评价回灌液悬浮物浓度和水动力条件对堵塞的影响，并探讨含水介质的物理堵塞机理。研究表明，随着回灌液中悬浮物浓度的增大，悬浮物首先在含水介质的表层沉积，当悬浮物浓度为50、100、200mg／L时，回灌结束后砂柱表层介质的渗透系数分别降至初始的21％、13％和4％，表明表层发生了不同程度的堵塞现象；悬浮物浓度的大小对深部介质的渗透性影响较弱。另外，当进一出水面的水头差△H较／b（即水力坡度较／b）时，物理堵塞主要发生在砂柱表层，当△H为19．25cm时，回灌结束后表层渗透系数降为初始的7％；随着△H的增大，物理堵塞深度和程度越大，当△H为48．64cm时，19-34cm深度砂层渗透系数变成初始的60％。
The physical clogging process of aquifer was experimentally studied in laboratory by using a sand column. The space-time variation of permeability was measured to have a systematic analysis and evaluation on how to the concentration of suspended particles and hydrodynamic conditions influence the physical clogging, and to explore the mechanism of aquifer physical clogging. The research was showed that, the suspended particles were initially inclined to deposit at the surface layer with higher suspended particles concentration. When the suspended particle concentration of the recharge liquid were 50,100,200 mg/L,the surface permeability coefficient dropped to 21%, 13% and 4% of the initial respectively, This indicated that clogging of different levels occurred in the surface medium. Along with the increase of sand layer depth, the influence rate of the particle concentration was no longer distinct. In addition, external clogging occured in the ease of small in-and-out water head difference. The permeability coefficient of sur- face layer declined to 7% of the initial with a water head difference of 19.25cm when the recharge ended~ With larger water head difference, the clogging range and degree were greater, the permeability coefficient of 19-34cm sand layer was reduced to 60% of the initial with 48. 64cm water head difference.
出处
《中国海洋大学学报（自然科学版）》
CAS
CSCD
北大核心
2013年第10期97-101,共5页
Periodical of Ocean University of China
基金
国家水利部公益性项目(201001075)
国家自然科学基金项目(41172209)
国家科技支撑计划项目(2012BAB12B00)资助
关键词
人工回灌
悬浮物浓度
水动力条件
物理堵塞
artificial recharge
suspended particles concentration
hydrodynamic condition
physical clogging
