Carbon dioxide triple-point crystallizer improves sulfur recovery

Carbon dioxide triple-point crystallization (TPC) has been developed to produce pure liquid carbon dioxide absorbent for use in the Consolidated Natural Gas (CNG) acid gas removal process. The sharp separation of carbon dioxide from sulfurous compounds achieved by TPC makes TPC an attractive process to increase the hydrogen sulfide concentration of acid gas streams produced by other acid gas removal processes. TPC, together with CNG sulfurous compound absorption with liquid carbon dioxide, can improve the economics of conventional Claus sulfur recovery processes and achieve essentially zero emission of sulfurous compounds.