Frozen soil stratum thawing settlement test simulation device and method

Abstract

The invention provides a frozen soil stratum thawing settlement test simulation device and a method. The frozen soil stratum thawing settlement test simulation device comprises a reaction container provided with a reaction cavity, a pressurizing assembly, a temperature control assembly, a confining pressure assembly, a simulated guide pipe system, a drilling fluid circulating system, an acquisition and measurement device, and a control module, wherein the pressurizing assembly and the temperature control assembly are connected with the reaction container; the confining pressure assembly surrounds the side wall of the reaction container; the simulated guide pipe system comprises a guide pipe arranged in the reaction cavity and a drill rod arranged in the guide pipe in a penetrating mode, and an annulus is formed between the drill rod and the guide pipe; the drilling fluid circulating system comprises a drilling fluid storage tank, a fluid inlet pipeline communicated with the guide pipe,a fluid return pipeline communicated with the annulus, a heating device, a booster pump, a switch valve, and a filtering device arranged on the fluid return pipeline; the heating device, the boosterpump and the switch valve are arranged on the fluid inlet pipeline; the acquisition and measurement device is communicated with the reaction cavity; and the control module is connected with the pressurizing assembly, the temperature control assembly, the switch valve and the acquisition and measurement device. According to the frozen soil stratum thawing settlement test simulation device and the method, the change rule of the thawed water yield of the frozen soil layer and the stratum settlement amount under the conditions of different heating ranges and different heating temperatures can be obtained.

Description

technical field [0001] The present invention relates to equipment for research on strata thawing and subsidence in the exploration and development of resources in permafrost stratum regions, in particular to a device applied to simulation tests of stratum thawing and subsidence in the process of drilling into permafrost strata, and using the device to conduct thawing and subsidence tests on permafrost strata simulated method. Background technique [0002] Large areas of permafrost are widely developed in the Arctic, sub-Arctic, my country's Qinghai-Tibet Plateau, and Xinjiang. In addition to conventional oil and gas resources, these areas also contain a large number of natural gas hydrates, which have great development value. However, drilling in permafrost faces enormous technical challenges. Specifically, due to the heat exchange between the drilling fluid and the formation, the temperature of the permafrost layer rises and melts, and the bearing capacity of the permafros...

AI Technical Summary

Problems solved by technology

However, drilling in permafrost faces enormous technical challenges

Specifically, due to the heat exchange between the drilling fluid and the formation, the temperature of the permafrost layer rises and melts, and the bearing capacity of the permafrost drops sharply. The wellhead and surface conduits are prone to instability and subsidence under the wellhead load, resulting in interruption of operations. Seriously affect work safety

[0003] At present, some scholars have carried out numerical simulation of finite element analysis on the stratum settlement in the process of drilling into permafrost, but there are only a few studies on the simulation experiments on the permafrost stratum heat-thawing subsidence

At the same time, there is a lack of research on the relationship between heating range, heating temperature, permafrost thawing water discharge, and stratum subsidence. The prediction of stratum subsidence still needs to be paid attention to, and there is no simulation of permafrost-containing strata that controls the heating temperature and heating range. Settlement test device, the prediction accuracy of formation settlement under different conditions is not high

Images