METHOD TO PRODUCE HEAVY AND/OR HIGHLY-VISCOUS HYDROCARBONS FROM UNDERGROUND FIELD Russian patent published in 2008 - IPC E21B43/24 

FIELD: hydrocarbon production, particularly to produce hydrocarbons from underground tar sand deposit or heavy oil deposit, namely by thermal treatment.

SUBSTANCE: method involves drilling injection wells having horizontal end sections and producing wells with horizontal end sections in deposit under level of injection well used for hydrocarbon production; preparing said wells for further operation; creating permeable zone between injection and producing wells. Injection and producing wells are drilled in accordance with one pattern with specified distance between the wells. Each casing pipe to be lowered in injection and producing well before end section forming is provided with position-finding means and with hollow bushes filled with easy destructible material. The bushes are arranged over position-finding means within necessary reservoir opening interval and are previously installed in wall. The bushes are sealed with downwardly movable cap installed from bush interiors. Then deflector is lowered in each well up to cap movement and establishing cooperation with position-finding means. The position-finding means guides outlet deflector channels in hollow bushes. Horizontal end sections of each well are serially enlarged through each hollow bush. After that packer is installed over hollow bushes of each well to isolate hole annuity between casing pipe and heat-insulated pipe string to prevent heat action on well section over packer. At least one well pair including injection and producing wells is drilled.

EFFECT: simplified production and increased accuracy of horizontal well section direction in deposit, as well as increased efficiency of oil deposit development due to extended deposit coverage with horizontal well sections and decreased heat action on well walls during well operation.

2 cl, 2 dwg