Shallow hole reinforcing method suitable for high-temperature geothermal well

Abstract

The invention belongs to the field of geothermal resource development, and particularly discloses a shallow hole reinforcing method suitable for a high-temperature geothermal well. According to the method, through shallow stratum stability analysis, shallow drilling arrangement and depth, well body structure, injected high-temperature cement amount calculation and a cement injection scheme, a nearly-circular cement reinforcing body with the diameter of about 12 m is formed on the periphery of a geothermal well shaft, the stratum on the periphery of the geothermal well is reinforced, and heat convection on the periphery of the well shaft is converted into heat conduction; the heat transferred from the shaft to the periphery is greatly reduced, so that the heat display around the shaft does not change obviously, and the risks of gas explosion and collapse are reduced.

Description

technical field [0001] The invention belongs to the field of geothermal resource development, and in particular relates to a shallow hole reinforcement method suitable for high-temperature geothermal wells. Background technique [0002] The high-temperature geothermal field is the drainage area of ​​underground hot water. The surface is mostly calcified, spring blooms, hot springs, and gas-emitting surfaces. The shallow deposits are mostly calcareous or siliceous cemented. The geological conditions are poor. During the exploration and development of geothermal fields, it is inevitable to implement geothermal production wells in the thermal display area. Due to the high porosity, strong water content and strong thermal convection in the Quanhua cement, the following safety hazards are likely to be caused during the geothermal well test or production process Hidden dangers: [0003] (1) gas explosion [0004] The travertine or silica flower near the high-temperature well is...

AI Technical Summary

Problems solved by technology

[0004] The travertine or silica flower near the high-temperature well is not dense, and underground cold water accumulates in the cracks. In the case of continuous production, due to the high temperature in the wellbore (generally greater than 130°C), heat convection is formed around the wellbore, which quickly heats the cold water around the wellbore to Boiling, the continuous vaporization and expansion of cold water, if the steam in some areas cannot be discharged smoothly, under the condition of continuous heat conduction, local high pressure will be generated, and there is a risk of gas explosion

[0005] (2) Collapse

[0008] In the case of continuous production, gas is emitted around the well platform, which changes the pressure balance state around the well platform, which will inevitably cause changes in the form of nearby surface thermal displays. The original hot springs may disappear, and new thermal displays may appear. The life and production of the villagers are likely to cause adverse effects

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