Downhole Heater Cables for Oil Shale Recovery

78469S Downhole heaters, capable of long-term 900¿C operation, are needed to assist in oil shale recovery. Currently available mineral-insulated (MI) cables are not capable of surviving the temperature or downhole environmental conditions encountered in this application. Additionally, the insulation must exhibit good electrical properties and resistance to the humidity encountered in downhole environments. The composite insulation process must also be scalable to wrap conductor lengths on the order of 2,000 to 5,000 feet. This project will fabricate prototype heater cables with a high-temeprature composite insulation system for oil shale recovery applications. In Phase I, heater cables up to 6 feet in length with composite insulation materials will be designed, fabricated, and tested using parameters that simulate the thermal, mechanical, and electrical properties required for this application. Critical manufacturing parameters will be identified and optimized. The Phase II will continue the development of the composite insulation materials and scale up the process to produce longer lengths. Commercial Applications and other Benefits as described by the awardee: The new heater cables should be (1) capable of extended operation at elevated temperatures, (2) able to withstand the downhole environmental conditions, and (3) produced using a process that is scalable to meet end-user production requirements. They should serve as an enabling technology for the economically viable recovery of oil from shale deposits. It is estimated that the United States possesses approximately two-thirds of the world¿s oil shale deposits.