Extraction device for undersea gas hydrate and extraction method thereof

Abstract

The invention discloses an extraction device for undersea gas hydrate and an extraction method thereof, which is characterized in that the device is directly communicated with undersea (10) gas hydrate layer (9) through a hollow rigid body (2); or the hollow rigid body is communicated with undersea (10) gas hydrate layer (9) through layers of sand and clay (8) or impermeable bed (11); a water pump (4) and a test and supervisory equipment (5) are provided on one side of the hollow rigid body, the water pump is connected with a drain pipe (3) which is above the sea level (7) through a pipe, the test and supervisory system is connected with an image pickup system and a pressure testing system, and a gas collecting pipe (1) is arranged on the top of the inside of the hollow rigid body. The extraction method comprises the following steps: 1) a hollow rigid body is built on the sea separated with water, and the hollow rigid body is communicated with undersea gas hydrate layer; 2) water in the hollow rigid body is drained out via a water pump to lower the water height in the hollow rigid body and reduce the pressure acting on the gas hydrate layer and the gas hydrate is decomposed into gas and water when the pressure acting on the gas hydrate layer is less than the balance pressure; 3) the decomposed gas escapes upward, is discharged through the gas collecting pipe and is collected.

Description

technical field [0001] The invention relates to a seabed natural gas hydrate exploitation device and a exploitation method thereof, belonging to the field of natural gas hydrate exploitation. Background technique [0002] Natural Gas Hydrate (NGH for short) is composed of natural gas and water molecules. It mainly exists in land permafrost and seabed sediments. , so it is also called "combustible ice". Natural gas hydrate is currently one of the most promising new high-efficiency clean energy sources. Each cubic meter of natural gas hydrate can release 164 cubic meters of methane and 0.8 cubic meters of water (Kvenvolden K.A.A review of the geochemistry of methane in natural gas hydrate[ J].Organic Geochemistry, 1995, 23:997-1008.), its energy density (the amount of methane per unit volume of sediment under standard conditions) is about 10 times that of other non-traditional energy sources, which is conventional natural gas and coal and black pages 2 to 5 times the energy ...

AI Technical Summary

Problems solved by technology

[0008] Among the above natural gas hydrate mining methods, the thermal stimulation mining method, the chemical reagent method and the decompression mining method all have their own shortcomings, and it is difficult to apply them to the actual natural gas hydrate mining. especially important

Images