Construction method of sandstone type geothermal well and reinjection well

Abstract

The invention belongs to the technical field of construction methods for geothermal wells and reinjection wells, and discloses a construction method for sandstone-type water-discharging geothermal wells and reinjection wells. Its main technical features are: the outlet geothermal well utilizes the aquifers of all water-bearing groups in the heat storage section; the pressure in each aquifer in the water-bearing group is measured through the outlet geothermal well, and when the recharge well is completed, the recharge layer of the recharge well It is installed in the aquifer with low groundwater pressure and high permeability coefficient, and blind pipes are used in other aquifers, so that the water in the aquifer with high pressure cannot flow into the aquifer with low pressure and high permeability coefficient through the recharge well. The water recharged through the reinjection well quickly enters the aquifer where the reinjection layer is located, the reinjection speed is fast, the reinjection volume is large, and the reinjection efficiency is high; the distance from the reinjection well to the outlet geothermal well is 1 of the influence radius of the outlet geothermal well / 2‑2 / 3, which not only ensures the amount of recharge but also prevents groundwater recharge thermal breakthrough.

Description

technical field [0001] The invention belongs to the technical field of construction methods for sandstone-type geothermal wells, and in particular relates to a construction method for sandstone-type geothermal wells with outlet water and reinjection wells. Background technique [0002] Geothermal is a clean, cheap, renewable and directly usable new energy. The development and utilization of geothermal resources can replace a large amount of petrochemical energy such as coal and natural gas, which is conducive to improving the existing energy structure, reducing energy consumption and cost, and minimizing waste gas, dust, and noise pollution. According to estimates, my country's currently proven exploitable geothermal resources are equivalent to the calorific value of 32.84 million tons of standard coal per year. Based on an average of 22.6kg of carbon dioxide, 17.87kg of sulfur dioxide, 15.39kg of soot, 7.50kg of industrial dust, and 96.06kg of industrial solid waste emitte...

AI Technical Summary

Problems solved by technology

At present, there are the following problems in geothermal utilization: First, in order to reduce the cost of geothermal energy utilization, geothermal is simply equated with general water resources development, excessive exploitation, only pumping but not irrigation

As a result, the development of geothermal resources has been seriously affected. In many places, the water level has dropped, the temperature has dropped, resources have been exhausted, and land subsidence has been caused. In all the aquifers in , due to the different geological structures in different aquifers in the same aquifer group, the groundwater pressure and hydraulic permeability coefficient in different aquifers are different, so that the water in different aquifers has pressure differences and hydraulic permeability coefficients Different, causing the water in the aquifer with high groundwater pressure to flow into the aquifer with low pressure and high permeability coefficient, which affects the recharge amount and recharge efficiency, and the recharge amount is low

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