Thermal jet natural gas hydrate exploitation device, system and method

Abstract

The invention discloses a thermal jet natural gas hydrate mining device, system and method, the mining device comprises a continuous pipe capable of rotatably drilling in a natural gas hydrate layer, the continuous pipe sprays hot water outwards during rotation to form thermal jet, and the thermal jet is used for performing jet cracking mining on natural gas hydrate; a casing pipe is arranged outside the continuous pipe, the continuous pipe extends out of an opening in the tail end of the casing pipe to enter a natural gas hydrate layer, and hot water carries the natural gas hydrate subjected to injection cracking decomposition to flow back and be recycled through an annular gap between the casing pipe and the continuous pipe. Hot water is used for replacing conventional drilling fluid, a drilling tool is used for driving the continuous pipe to rotate, stable rotating thermal jet flow is formed, a larger swept area can be obtained, and the exploitation amount is increased; meanwhile, guiding and logging tools are installed at the tail end of the continuous pipe, the drilling direction of the continuous pipe is controlled in real time, rotary drilling of the continuous pipe in the natural gas hydrate layer all the time is effectively achieved, and the high recovery rate is kept in the mining process.

Description

technical field [0001] The invention relates to the technical field of natural gas hydrate development, in particular to a thermal jet natural gas hydrate exploitation device, system and method. Background technique [0002] my country's demand for clean energy keeps growing at a high speed, but my country's dependence on foreign oil and natural gas resources is getting higher and higher, seriously affecting my country's energy security. Natural gas hydrate reserves are abundant in my country. Experts estimate that natural gas hydrate reserves are twice the current coal and oil reserves combined, and my country has successfully drilled combustible ice in the Shenhu sea area and the Qilian Mountain permafrost. 1m 3 Combustible ice can produce 164m 3 methane, and the combustion product CO 2 and H 2 O, belongs to high calorific value, clean and pollution-free green energy. [0003] Theoretically, there are two ideas for the development of natural gas hydrates: one is the s...

AI Technical Summary

Problems solved by technology

The main disadvantages of this method are low energy efficiency, large investment, and limited coverage of heating exploitation, and it is difficult to avoid the collapse problem during the development of shallow seabed gas hydrate

[0005] The high input cost of injecting chemical reagents, environmental pollution and other issues strictly limit the application of this technology; the development technology of injecting supercritical carbon dioxide is still lack of theoretical demonstration, and the acquisition, storage and cost of supercritical carbon dioxide also restrict this technology Applications

[0006] In addition, there is fracturing technology in the field of conventional oil and gas development. Since it cannot form stable fractures in non-diagenetic formations, this technology is also not suitable for the development of non-diagenetic natural gas hydrate in shallow oceans.

[0007] Therefore, there is still no method to realize the efficient development of shallow seabed gas hydrate

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