Patent ID: 8281592

Claim:
A method comprising: pressurizing a heat source stream to a pressure equal to a pressure to a multi-component heat carrier (MCHC) fluid to form a pressure, adjusted heat source stream, forwarding the pressure, adjusted heat source stream to a heat source inlet port of a direct heat exchange apparatus located in an upper portion of a middle section of the direct heat exchange apparatus, concurrently, forwarding a pressure adjusted, fully condensed multi-component heat carrier (MCHC) stream to a MCHC inlet port of the direct heat exchange apparatus located at a lower portion of the middle section of the direct heat exchange apparatus, where the MCHC fluid has a lower density than the heat source stream, exchanging heat between the heat source stream and the MCHC stream in the direct heat exchange apparatus as the MCHC fluid rises in the direct heat exchange apparatus and the heat source stream falls in the direct heat exchange apparatus, accumulating a MCHC saturated vapor or a MCHC partially vaporized fluid in an upper section of the direct heat exchange apparatus, accumulating the cooled heat source fluid in a lower section of the direct heat exchange apparatus, accumulating a mineral precipitate in a bottom section of the direct heat exchange apparatus, withdrawing a spent heat source stream from the lower section of the direct heat exchange apparatus via a heat source outlet port located in an upper portion of the lower section of the direct heat exchange apparatus below the MCHC inlet, withdrawing the saturated MCHC vapor from the direct heat exchange apparatus as a MCHC saturated vapor stream or a partially vaporized MCHC stream via a MCHC outlet port located in a top portion of the upper section of the direct heat exchange apparatus, passing the MCHC saturated vapor stream or a partially vaporized MCHC stream through a heat exchange apparatus in counter-flow with a fully condensed working fluid stream to form a fully condensed MCHC stream and a fully vaporized or fully vaporized and superheated working fluid stream, and passing the fully condensed MCHC stream through a circulating pump to adjust the pressure of the stream to an entry pressure to form the pressure adjusted, fully condensed MCHC stream.