Mining method of natural gas hydrate in shallow non-diagenetic strata of deep seabed

Abstract

The invention discloses a green mining method of natural gas hydrate, which is used for the mining of natural gas hydrate in shallow non-diagenetic formations on the deep seabed. The green mining method of natural gas hydrate comprises: in the storage area of ​​natural gas hydrate , under the pressure and temperature in the natural environment, the natural gas hydrate reservoir is mined in a solid form, the solid matter containing the natural gas hydrate is collected and crushed into particles, and the seawater is mixed with the particles by ejection to form a gas hydrate Liquid-solid multiphase mixture flow; the gas-liquid-solid multiphase mixture flow is lifted to the sea through a closed pipeline with a pressurization system; the gas-liquid-solid multiphase mixture flow is lifted to the sea through a closed pipeline The gas-liquid-solid multiphase mixture is separated and processed to obtain natural gas. The invention realizes the safe and green exploitation of the natural gas hydrate and avoids potential dangers in various aspects.

Description

technical field [0001] The invention relates to the technical field of development of unconventional oil and gas resources, in particular to a green mining method for mining natural gas hydrate in shallow non-diagenetic formations on the deep seabed. Background technique [0002] With the sustained and rapid development of my country's national economy, the contradiction between energy supply and demand has become increasingly prominent. In 2012, my country imported 207 million tons of crude oil, becoming the world's second largest importer of crude oil, and its dependence on foreign countries reached 56.7%, approaching or exceeding the internationally recognized energy security. Wire. Therefore, while intensifying the exploration and development of new fields in new oil and gas areas, searching for new alternative energy sources has become an important strategic measure to ensure national energy security and national security. [0003] The exploration, development and utili...

AI Technical Summary

Problems solved by technology

[0008] 1) The disorderly decomposition of weakly cemented gas hydrate in shallow non-diagenetic formations on the deep seabed may bring about potential submarine landslides and other geological disasters. The reservoir has no obvious structural boundaries and tight cap rocks. With the large-scale development of gas hydrates, the stratigraphic structure will begin to become evacuated, which may lead to instability of the seabed strata;

[0009] 2) The natural gas hydrate in the shallow non-diagenetic strata of the deep seabed is mainly decomposed into natural gas and water, and a large amount of natural gas will cause the greenhouse gas effect and cause damage to the atmospheric environment;

[0010] 3) Due to the decomposition of natural gas hydrate, a large amount of natural gas is released disorderly, and the free expansion of a large amount of gas may cause disasters to ships and air vehicles on the sea surface

[0011] In the existing natural gas hydrate mining technology, the natural gas hydrate deposits with certain reservoir caprocks in the deep sea are usually converted into gas and water underground by decompression\heat injection\injection agent, etc., the converted gas is collected, and then Produced through underwater production facilities or floating production facilities, this method can only be adapted to the development of deep-water diagenetic gas hydrates, and the current production efficiency cannot meet the threshold for industrial development, and this method cannot realize deep-water shallow formations. Development and Utilization of Cemented Natural Gas Hydrate

[0012] In summary, no matter whether it is natural gas hydrate in well-cemented deep seabed shallow diagenetic formations or poorly cemented deep seabed shallow non-diagenetic formations, in the prior art, the above three problems None of them were effectively addressed during the development process

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