Development of polymer concrete liners and coatings for use in geothermal applications.

摘要

The results of a research and field testing program conducted by Brookhaven National Laboratory for the Geothermal Division of the US Department of Energy to develop polymer concrete (PC) liners and coatings for use in geothermal applications are presented. Whenever possible, carbon steel is used in geothermal facilities for components such as piping, well casings, and containment vessels. However carbon steel is subject to severe corrosion when exposed to some geothermal fluids and brines, leading to the use, in some cases, of very expensive high alloy steels. Results of laboratory tests done in simulated geothermal environments (pH 2 hydrochloric acid steam at 200(degree)C) have shown that PC materials can be used as liners and coatings to protect carbon steel surfaces from corrosion. In situ field testing of 8-in. (203-mm) inside diameter (ID) by 12-in. (305-mm) long spool sections and 12in. ID (305-mm) wellhead tee sections in operational geothermal facilities is currently being done to verify the laboratory test data. Economic studies have shown that the capital cost of the vessels and piping in a typical geothermal facility can be significantly reduced through the use of protective PC linings and coatings. As a result PC lined components are currently being used commercially at two geothermal sites.