Exploitation method and system of land methane hydrate

Abstract

The invention provides an exploitation method and a system of land methane hydrate. The method comprises the steps that two silos different in depth and not far in distance are drilled by a drilling machine to a combustible ice layer; two communicated cavities are formed by an explosive at the bottoms of the silos; high-temperature fresh water is continuously injected into the bottom of the deeper silo to allow methane to be changed to a gas state from a solid state; gas state methane is sprayed out from the other silo, compressed and cooled for moisture removal, and refrigerated to -162 DEG C by a nitrogen compressor to become liquid methane or made into methane hydrate again to be stored; and a part of exploited methane serves as a fuel for heating the fresh water. The method and the system have the benefits that methane hydrate can stop decomposing once injection of the high-temperature fresh water is stopped; heat preservation measures are taken for pipelines and container tanks, so that no heat energy is wasted; a diesel generator supplies power, so that the manufacturing cost is low, and operation is reliable; the method belongs to a gap penetration displacement method, so that underground collapse cannot be caused; and carbon dioxide is the only emission, and other rejected materials are wholly backfilled to the underground and recycled.

Description

(1) Technical field [0001] The present invention relates to a mining method and system for terrestrial methane hydrate (also known as "natural gas hydrate" and "methane hydrate"), especially a method and system with simple structure, reliable operation, low cost, energy saving, environmental protection, safety, controllability and pollution-free A method and system for exploiting marine oil and gas resources that discharge pollutants, and the technical field belongs to the field of exploiting land oil and gas resources. (2) Background technology [0002] Terrestrial methane hydrate is a crystal formed by the combination of methane gas and water molecules in a low-temperature and high-pressure environment. It mainly exists in the permafrost of the land plateau. One carbon atom emits less carbon dioxide after combustion, and no sulfide is produced. It is an ideal clean energy. At present, there is no mature land methane hydrate mining method and system put into commercial ope...

AI Technical Summary

Problems solved by technology

At present, there is no mature land methane hydrate mining method and system put into commercial operation in the world, because the existing mining methods are relatively complicated, costly, and lack of controllability and operability , it is easy to cause the leakage of methane gas, causing environmental pollution and the greenhouse effect of the atmosphere. It is still in the stage of laboratory exploration and cannot be put into commercial operation.

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