DEVELOPMENT METHOD OF UNDERWATER GAS-HYDRATE DEPOSITS Russian patent published in 2015 - IPC E21B43/00 

FIELD: oil and gas industry.

SUBSTANCE: method involves destruction of massif of a hydrate-containing manifold with high-pressure water jets, formation from destructed material of pulp in a near-bottom volume covered with a dome, lifting of the pulp containing gas and gas-hydrate onto a floating structure via a pipeline and separation of the pulp into gas, water and solid material with gas transfer to a state suitable for transportation. According to the invention, massif of the hydrate-containing manifold is converted to a solid body-liquid fine suspension with gas-hydrate particle size of 10-20 mcm. For that purpose, it is influenced with high-pressure jets formed in the near-bottom volume covered with the dome. Besides, the volume of the pulp formed in this volume is treated with an ultrasound with parameters causing cavitation effects in it. A hydrate-containing suspension is formed with content in it of a disperse phase of gas-hydrate of up to 20-25%. Capacity of destruction devices of massif of the hydrate-containing manifold is controlled proportionally to pressure in the pipeline in its near-bottom section. An ice pulp formed at dissociation of the gas hydrate is used for cooling of compressed gas - a product of dissociation of a gas-hydrate pulp.

EFFECT: increasing well performance efficiency of a gas-hydrate deposit.

6 cl, 5 dwg