Shaft self-loop heat exchange experiment device and method

Abstract

The invention relates to a shaft self-loop heat exchange experiment device and method. The experiment device includes a heat exchange system, an injection and production system, a heating and insulation system and a data acquisition system, wherein the heat exchange system is used for simulating a shaft of a geothermal reservoir and providing a flow channel between a heat-carrying fluid and the geothermal reservoir, the injection and production system is used for injecting the low-temperature heat-carrying fluid into the heat exchange system through a booster pump, collecting the produced hotfluid and cooling and storing the produced hot fluid, the heating and insulation system is used for performing heating and head insulation of the shaft and a sand-filling cylinder to shape the high temperature environment of the geothermal reservoir and simulate stable heat source supply, and the data acquisition system is used for monitoring and recording temperature and pressure data at key locations of the heat exchange system, the injection and production system and the heating and insulation system. The experiment device is advantaged in that the experiment device can simulate the processof circulating flow, heat exchange and heat collection of the heat-carrying fluid in the oil jacket annulus-oil pipe, can monitor temperature and pressure changes along the shaft and at the inlet andthe outlet in the heat exchange process, can analyze thermal property change of the heat-carrying fluid in the shaft and measure the heat exchange rate, heat flux and a heat transfer coefficient of the shaft, and can be used for screening heat-carrying fluids, optimizing injection-production parameters and evaluating factors affecting the shaft heat exchange rate.

Description

technical field [0001] The invention belongs to the technical field of geothermal exploitation, and in particular relates to a wellbore self-circulating heat exchange experiment device and method. Background technique [0002] EGS, which uses hydraulic fracturing to build artificial fracture networks in hot dry rocks, is currently the most commonly used hot dry rock mining technology, but large-scale hydraulic fracturing is subject to certain technical, environmental and economic limitations. The flow channel formed by hydraulic fracturing is prone to late closure and blockage under the stress of the formation and the physical and chemical action between water and rock, and cannot provide efficient flow and seepage channels for a long time; during the fracturing process of brittle hot dry rock, its fractures The extension and distribution of fracturing are uncontrollable, which may lead to cracks in the surrounding rock and caprock, resulting in a large loss of heat-carrying...

AI Technical Summary

Problems solved by technology

At present, the use of single well self-circulation technology to exploit geothermal energy mainly focuses on the use of abandoned vertical wells to exploit geothermal energy in oil and gas fields, but there are few studies on the use of self-circulation to exploit hot dry rock geothermal energy. So far, there has been no research on the use of wellbore self-circulation to exploit hot dry rock. Experimental device and method

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