The Research On Attenuation Characteirstics Of Groundwater Artificial Recharge In Shenyang City

The attenuation of recharge volume remains a matter of debate during the studyon groundwater source heat pump (WSHP), which has been of broad scientificinterest by researchers all over the word. However, past studies focused mainly onclogging mechanism. Based on the experimental laboratory work, the diversity ofdevelopment processes with different clogging conditions and the determination ofrecharge yield under different aquifers have been considered. Based on the data fromthe recharge pilot site (Shenyang), attenuation characteristic of groundwater rechargeunder different conditions are discussed in this paper.Four groundwater recharge experiments are conducted in this study, including nopressure recharge, constant pressure recharge, no lifting pressure recharge andcontinuous lifting pressure recharge. Firstly, cause-effect method was used to analyzethe attenuation cause of recharge, and the results showed natural attenuation andclogging attenuation was the main factors in the study area. The time of occurrence,the duration time of action, and the effect of action is compared between naturalattenuation and clogging attenuation under different conditions. Then the variationtrend of recharge volume is fitted with an effective attenuation formula, which isavailable in the study area. Finally, measurements of solving recharge attenuation arepresented.The study is conducted in the confined aquifer, and the main conclusions drawnfrom the study are as follows:1. The attenuation of groundwater recharge is ascribedto natural attenuation and clogging attenuation, and natural attenuation mainly occursat the beginning of experiments, while clogging attenuation starts after several days.2.The increase of the influence radius is attendant with the increase of the pressure, andhydraulic conductivity decreased in the region of influence radius.3. When theclogging attenuation is finished, and the water flows with a stable state, the recharge volume is increased with the increasing of pressure. The relationship betweenrecharge pressure and recharge yield basically accords with a linear function.4.In thepressure recharge experiment, natural attenuation developed quickly with limitedaction effect, and the attenuation is mainly caused by clogging attenuation. In the nopressure recharge experiment, the main factor is natural attenuation, and the change ofhydraulic conductivity is more obvious that that of pressure recharge experiment.5.The attenuation coefficient in no pressure recharge experiment is bigger severalorders of magnitude than that of pressure recharge experiment.6. Lifting pump is thebest way to solve the problem of recharge clogging, and the action should not exceed12hours.7. The right way is to keep air-out and lift appropriately during pressurerecharge in the study area.