Internally Insulated Pipe Systems for Long-Distance Transport of Thermal Energy. A Final Subcontract Report

摘要

Presented are the results of a study to evaluate the preliminary feasibility of internally insulated pipe systems for the transport of thermal energy over distances of 5 to 50 km. The specific objectives were to screen technologically feasible concepts, to determine the incremental cost relative to conventional externally insulated pipe, and to recommend areas requiring further research and development to commercialize the long distance transport of thermal energy. Two conceptual designs for internally insulated pipe systems were found which are technically feasible, from a standpoint of pressure induced stresses and thermal losses. At steam temperature range of 600 to 1000 exp 0 F and pressure range of 600 to 1800 psi, the internal insulation cases are shown to provide less expensive transport of energy than conventional, external insulation pipe. At hot water temperatures between 250 to 450 exp 0 F for similar power levels, internal insulation is comparable to external cases at the conservatively priced cost of energy at source of $2.63/10 exp 6 Btu. At higher source cost, internal insulation would be more favored compared to external. It was determined that the primary reasons for the economic benefit of internal insulation compared to externally insulated pipe are the reduced pipe line length and hence the reduced material cost and heat loss cost penalty at high fluid temperature. (ERA citation 08:002527)