GAS-HYDRATE RECOVERY METHOD Russian patent published in 2006 - IPC E21B43/24 E21B7/00 

FIELD: gas-hydrate field development.

SUBSTANCE: method involves drilling modules, wherein each module includes directed wells with horizontal multilateral ends; injecting heat-carrier fluids in some modules; recovering hydrates in non-equilibrium gaseous state from the other modules. The horizontal multilateral ends of the wells are uncased and have fan structures so that the ends extend through gas-hydrate field thickness for distance equal to lengths of fan-like horizontal ends. Then vertical well is drilled in plane defined by horizontal multilateral end bottoms and vertical well borehole is crushed by directed blast perforation in level with corresponding bottom of fan-like multilateral end determined by navigational method. The directional vertical well is serially connected with each end of above fan-like structure. After that gas-hydrate is ignited at directional well borehole end and air is injected in the well to heat gas-hydrate field by straight combusting zone movement along horizontal ends in direction from directional well casing end to directional vertical well.

EFFECT: increased recovery rate, possibility to create single hydraulically connected drill bore system to stimulate gas-hydrate field.

6 cl, 1 dwg