Device and method for measuring influence of natural gas hydrate drilling pipeline microbend on flow field

Abstract

The invention relates to a device and method for measuring the influence of natural gas hydrate drilling pipeline microbend on a flow field. The device is composed of a driving motor 25, a drill rod 32, a transparent sleeve 33, a mixing tank 34, a water storage tank 1, a water pump 3, a first oxygenation pump 5, a pressure sensor 23, a pressure monitoring system 19, a second oxygenation pump 18 and a three-phase separator 28. The method comprises the steps that gas generated by the first oxygenation pump and water in the water storage tank enter the transparent sleeve at the same time, and thedriving motor drives the drill rod and a drill bit to rotate; the mixing tank is opened, and rock debris particles and nylon particles are added; circulating is performed until the pressure tends tobe stable; air generated by the second oxygenation pump enters the sleeve from a gas filling port to simulate decomposition of natural gas hydrate under the actual working condition; and different opening degrees of all gas filling port ball valves of the sleeve are adjusted respectively, and different decomposition amounts of the natural gas hydrate along with the change of the flow-back height are simulated. The device and method are reliable in principle and simple and convenient to operate, and provide detailed basic data and theoretical basis for exploitation of the natural gas hydrate.

Description

technical field [0001] The invention relates to the technical field of natural gas hydrate drilling, in particular to a device and method for measuring the influence of microbending of a natural gas hydrate drilling pipeline on a flow field. Background technique [0002] Natural gas hydrate is a clathrate compound formed by natural gas and water at a low temperature above freezing point and a certain pressure. It looks like ice but has a different crystal structure from ice. The exploitation of natural gas hydrate is usually carried out by drilling. After drilling into the reservoir, the natural gas hydrate enters the wellbore and is discharged upward in the annulus together with the drilling fluid. During the upward discharge, the natural gas hydrate will The decomposition is carried out with the change of flowback height, but due to the impact of seawater, the casing is slightly bent after being impacted during the mining process. When the microbending occurs, the flow fi...

AI Technical Summary

Problems solved by technology

The exploitation of natural gas hydrate is usually carried out by drilling. After drilling into the reservoir, the natural gas hydrate enters the wellbore and is discharged upward in the annulus together with the drilling fluid. During the upward discharge, the natural gas hydrate will Decomposition is carried out with the change of flowback height, but due to the impact of seawater, the casing is slightly bent after being impacted during the mining process

Images