Patent ID: 8579031

Claim:
A system configured to insulate an overburden of at least a part of a hydrocarbon containing formation, comprising: an opening in a part of the formation; a freeze well located in the opening, wherein a refrigerant is circulated through the freeze well to freeze at least a portion of the formation below the overburden, the freeze well comprising: a first conduit; an insulating material located between the first conduit and the overburden; a second conduit located inside the first conduit with an annular region between the first and second conduits, wherein the refrigerant enters the freeze well through the second conduit and exits the freeze well through the annular region; and one or more spacers in the annular region, wherein the spacers position the second conduit in the first conduit, and wherein the spacers promote turbulent flow of the refrigerant in the annular region.