DEVICE FOR WELLS THERMAL INSULATION IN PERENNIALLY FROZEN ROCKS Russian patent published in 2017 - IPC E21B36/00 

FIELD: oil and gas industry.

SUBSTANCE: device for wells thermal insulation in perennially frozen rocks is proposed, which includes a heat-insulating structure (1) between the cement wall of the borehole and the production pipe, comprising two co-axially arranged pipes (12, 13) and a vertical insulating partition (15) between them, forming two chambers with a medium that provides heat flow removal. It is new that external (16) and internal (17) isolated chambers are formed in the intertube space of the heat-insulating structure (1) using a vertical insulating partition (15) mounted on the packer element (14) located on the boundary of the thawing depth of the perennially frozen rocks. The outer chamber is filled with a non-freezing medium, which is an antifreeze, and the inner chamber is filled with a heat carrier for the well internal heat drawoff and is equipped with a forced coolant circulation system. In addition, the vertical insulating partition (15) is further provided with an external thermally conductive layer (22) with thermoelectric elements (23) installed with the possibility of electric current and an internal chamber (17) in contact with the coolant medium to pass through them.

EFFECT: increased efficiency of wells thermal insulation, prevention of perennially frozen rocks thawing throughout the well life, including the summer period, heat flow management and its reduction.

2 cl, 1 dwg