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地下水人工回灌可以高效地利用雨季丰沛的水量来缓解地下水过量开采造成的海水入侵、泉水断流等环境水文地质问题,但回灌堵塞一直是制约人工回灌效率的关键问题。针对雨洪水回灌携带的大量气泡问题,设计室内砂柱试验模拟装置,利用曝气水进行人工回灌,定时记录试验过程中测压管读数及出流流量,利用达西定律计算各层渗透系数,研究气相堵塞的发展过程和规律。结果表明:回灌过程中由于气相堵塞导致含水层渗透系数随时间呈指数衰减,气相堵塞主要发生在介质浅表层(0~30 cm),且随时间有向下发展的趋势,堵塞速率随深度的增加逐渐减小,在回灌过程中适时停灌进行排气有利于减小气相堵塞对回灌效率的影响。
Artificial recharge of groundwater can effectively utilize abundant rainfall in the rainy season to alleviate environmental hydrogeological problems caused by over-exploitation of groundwater such as seawater intrusion and spring breakage. However, plugging in recharge has always been a key issue that restricts the efficiency of artificial recharge. Aiming at the problem of a large number of bubbles carried by rainwater recharge, a sand simulator was designed to simulate indoor artificial sand recharge by aeration water. The piezometer readings and outflow were recorded regularly. Darcy’s law was used to calculate the permeation of each layer Coefficient to study the development and regularity of gas-phase blockage. The results show that the permeability coefficient of aquifer decays exponentially with time due to gas plugging in the recharge process. The clogging occurs mainly in the superficial layer (0-30 cm) of the medium, and tends to develop downward with time. The clogging rate increases with depth Of the increase gradually decreases. It is beneficial to reduce the influence of gas-phase blockage on the recharge efficiency by stopping the irrigation at the proper time during the recharge process.