Research On Heat Storage And Transportation In The Shallow Aquifer By River

Pore water storage in Cenozoic loose diluvial which is extensive along theriver, which provide human with the facilitate exploitation of groundwaterresources; alluviumthickness of the upper reaches valley in mountain area and themiddle reaches valley in the hills~semi-moutainous is often thin with shallowburied depth. Groundwater available exploitation of water resources andavailable energy (temperature) affected by the environment and the boundaryconditions and the empact will become more apparent near the river.Near Qingyi River Mountainous pass in southern Anhui Province, in therange of0.5~3.0km width along Qingyi river, Cenozoic loose deposit withthickness below15m, present typical dual structure, The upper part is silty claywith thickness less than3m, The lower part is a gravel layer with Muddy gravelbelow; well pump capacity and reinjection capacity can reach20~30m3/h inphreatic aquifer. A groundwater source heat pump system with a design maximumwater demand of230m3/h was built1.5km away from river. On the basis ofpumping and recharge tests, long-term dynamic observation of groundwater,surface water level and water temperature were carried out with the collection ofhydrological and meteorological information; A numerical simulation model withthe combination of groundwater flow field and temperature field based on thehydrogeological condition of the region where the instance located; Simulation ofimpact of river boundary on heat transfer process of phreatic water WithTOUGH2software. Quantitative study of the dynamic variation of water andenergy near the river boundary border was carried out.1. From the river to the hills, the thickness of the loose debris is graduallythinning to tip off, the aquifer water recharge capacity gradually decrease; theOutflow of the single well near the river water was significantly grea ter than theinstance wherelots, for the river border supply and the groundwater temperatureis also more obviously affected by river.2. Phreatic water temperature is obviously affected by environmental change.From November2011to December, the magnitude of the changes in watertemperature reaches1.5℃， for the annual amplitude would be greater.Changes in water temperature should be taken full account of for the design andoperation of water source heat pump system. 3. The instance Pumping~recharge scheme (in the upper reaches of thegroundwater flow, recharge of wells from the pumping well group of about110m),the heat-linkage phenomenon of heat will occur during both the heating periodand the cooling period, and cannot fully restored in the interi m period.4. Without changing of the instance Pumping~recharge scheme,watersource heat pump system, would safely operate only assuming that the site is inthe reach of200m away from the river.