Process and system for recovery of energy from geothermal brines and other water containing or hot water sources, which comprises direct contact heat exchange between the brine or hot water, and a working fluid, e.g. n-butane, in a heat transfer column, the heat transfer column being operated in the subcritical pressure region of the working fluid, preferably close to or approaching the apex of the saturated vapor curve for such working fluid on the Mollier enthalpy-entropy diagram for such fluid. The heated working fluid exiting the top of the heat transfer column is expanded through an expander to produce work. The discharge from the expander is cooled to condense working fluid which is separated in an accumulator, from condensed water vapor present in the working fluid, and the condensed working fluid is pressurized and fed back to the heat transfer column. Water from the accumulator can be fed to an H.sub.2 S removal system where good quality water can be recovered. Cooled brine or water from the bottom of the heat transfer column and water from the accumulator are fed to a flashing device such as a flash drum, and the working fluid flashed off is compressed and returned to the cooler at the expander discharge, for condensation and recovery. Also, entrained liquid phase working fluid can be separated from the cooled brine or water prior to flashing, and returned to the system. Uncondensible gases plus some working fluid losses are vented from the accumulator, and preferably the system can be operated under conditions to vent a minimum of uncondensible gases from the accumulator, and thereby reduce working fluid losses, Any accumulator vent gas can be fed to the H.sub.2 S removal system.
This application is a continuation-in-part of my copending applications, Ser. Nos. 589,068 and 611,310 now U.S. Pat. No. 4,089,175, both filed June 23, 1975, and Ser. No. 763,533, filed Jan. 28, 1977, the entire disclosures of which are incorporated herein by reference.
A power plant and method for the generation of power from flowing air utilizes a generally vertically extending duct having an inlet open to atmosphere at an elevation above an outlet. A spray system is mounted adjacent the inlet for spraying droplets of a predetermined amount of water into the air causing the air and droplet mixture to become cooler and denser than the outside air to create a down draft of fluid within the duct. A power system mounted adjacent the outlet recovers energy from the downdraft of fluid passing through it. The predetermined amount of water sprayed is greater than the amount of water that would theoretically and potentially evaporate in the air throughout the entire elevation over an unlimited time period using fresh water droplets. The power plant can also be synergistically combined with desalination systems and aquaculture.
A power plant and method for the generation of power from flowing air utilizes a generally vertically extending duct having an inlet open to atmosphere at an elevation above an outlet. A spray system is mounted adjacent the inlet for spraying droplets of a predetermined amount of water into the air causing the air and droplet mixture to become cooler and denser than the outside air to create a down draft of fluid within the duct. A power system mounted adjacent the outlet recovers energy from the downdraft of fluid passing through it. The predetermined amount of water sprayed is greater than the amount of water that would theoretically and potentially evaporate in the air throughout the entire elevation over an unlimited time period using fresh water droplets. The power plant can also be synergistically combined with desalination systems and aquaculture.
