Unattended full-automatic hydrate depressurization mining system

Abstract

The invention discloses an unattended full-automatic hydrate depressurization mining system. The unattended full-automatic hydrate depressurization mining system comprises an exploitation well system, an exploitation piston system, a wellhead device, a gas-liquid separation and depressurization system, a drainage depressurization system and a sea surface energy and communication system, wherein the wellhead device is installed on a wellhead of the exploitation well system, one end of the gas-liquid separation and depressurization system is connected with the upper part of the exploitation well system, the other end is connected with the drainage depressurization system, the exploitation piston system is installed in the exploitation well system and can move up and down along the exploitation well system, the exploitation well system depressurizes and exploits hydrates of a natural hydrate reservoir, and exploited natural gas and water are sent into the gas-liquid separation and depressurization system through the exploitation piston system. The whole production process of the system is unattended, each well does not need to be provided with a sea surface natural gas treatment and processing platform, a single well is allowed to be low in daily output, the influence on the marine ecological environment is small, meanwhile, safety risks such as sudden collapse of the sand production seabed are reduced, and the operation cost is greatly reduced.

Description

technical field [0001] The invention relates to the technical field of hydrate depressurization mining, in particular to a fully automatic unattended fully automatic hydrate depressurization mining system under marine working conditions. Background technique [0002] Gas hydrate is an ice-like solid formed by gas (or volatile liquid) and water under certain temperature and pressure conditions, commonly known as combustible ice, widely distributed in the sediments below the surface of the tundra and under the seabed at the continental margin middle. Natural gas hydrate has a huge natural gas storage capacity, and the natural gas hydrate reserves in the world are very huge, equivalent to 2×10 5 100 million tons of oil equivalent, which is twice the total carbon content of conventional fuels in the world. [0003] At present, gas hydrate gas reservoirs have been discovered in 79 countries and regions in the world. However, large-scale commercial mining of combustible ice fac...

AI Technical Summary

Problems solved by technology

However, in the late stage of test production, the decomposition radius expands, and the flow resistance further increases. With the increase of production pressure difference, the gas production at the wellhead continues to decrease, and further increase of production pressure difference cannot make up for the production decline.

Therefore, the existing mining technologies and methods are difficult to achieve the purpose of commercial mining

The challenges faced include: 1) The particularity of natural gas hydrate reservoirs leads to the development of natural gas hydrate reservoirs, which easily induces environmental and geological disasters, and at the same time there is a problem of low production efficiency; 2) The existing drilling and completion technology and equipment are difficult to meet the needs of hydrate reservoir development, Special support is required; 3) During the hydrate development process, the water production is large, and it is difficult to quickly separate gas and water downhole; 4) There is no mature method to improve the energy efficiency of production to ensure the economy of hydrate development

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