US 5,366,514 A · Salt plant evaporation

Abstract

This invention relates to an evaporative salt plant installation including methods of operation and apparatus which produce high purity salt economically and in high yield comprising the combination of a gas turbine which drives a vapor compressor, whose exhaust gases are used to produce steam to drive a topping steam turbine generator, which in turn generates the electrical energy requirements of the plant, and wherein the discharge vapors from the steam turbine are combined with the discharge vapors from the vapor compressor, which is in turn in combination with a vapor compression evaporator and a purge evaporator, whereby both evaporators produce salt, and where the overhead vapors of the purge evaporator are used in a brine cooled condenser to preheat input cold brine, thereby producing water condensate which is recovered, along with evaporator steam chest condensate streams, and used in solution mining underground salt, thereby allowing for both the productive use and recovery of substantially all the raw material and energy inputs to the plant, and the friendly environmental operation of the plant.

Claims26

Dependent claims

A method for producing high purity salt of at least about 99.99% NaCl content from brine in an evaporative salt plant installation which comprises:

employing the shaft energy produced by a combustion gas turbine to drive a vapor recompressor while employing the gas turbine exhaust gases in a heat recovery steam generator to produce high pressure steam,
employing this high pressure steam to drive a topping steam turbine which produces the electrical energy requirements of the evaporative salt plant installation,
combining the discharging vapors from the topping steam turbine with the discharge vapors from the vapor recompressor,
employing the combined vapors to heat the brine in the circulating heater of at least one vapor recompression evaporator, said vapor recompression evaporator being supplied with preheated brine to produce a salt slurry, separating the solid salt from the mother liquor, and purging a minor portion of the mother liquor which is supplied to a purge evaporator where it is evaporated to produce a second salt slurry, recycling the major portion of the mother liquor to said vapor recompression evaporator and supplying the gaseous overhead vapors to the vapor recompressor, and
condensing the vapors produced by the purge evaporator in a brine cooled condenser where the input brine is used as the coolant, preheated and then supplied to the vapor recompression evaporator.

2 more elements

An evaporative salt plant installation for producing high purity salt of at least about 99.99% NaCl content comprised of:

a vapor recompression evaporator with a circulating heater:
a combustion gas turbine whose shaft energy drives a vapor recompressor in overhead vapor communication with said vapor recompression evaporator which in turn provides heat to said steam vapor recompression evaporator circulating heater which includes recovery of the gas turbine exhaust heat to generate steam which is used to drive a topping steam turbine whose shaft energy drives an electrical generator, which produces the electricity required to run the plant, and whose exhaust vapors are combined with the discharge vapors of the vapor recompressor, said topping steam turbine exhaust vapors being used to effect additional boiling, above that effected by the discharge vapors of the vapor recompressor, in the vapor recompressor evaporator circulating heater, to produce salt;
said vapor recompression evaporator being in overhead vapor connection with the circulating heater of a purge evaporator and in liquid connection with the body of the purge evaporator, which utilizes steam resulting from the additional boiling effected in the vapor recompression evaporator by exhaust heat recovery,to produce additional salt;
said purge evaporator being in overhead vapor connection with a brine cooled condenser, wherein the water vapor overheads from the purge evaporator are used in said brine cooled condenser to initially preheat the input brine before final preheating, utilizing sensible heat from circulating heater condensate, before introduction of the brine to the vapor recompression evaporator.

1 more element

Dependencies are inferred from the claim text.

Salt plant evaporation

Life of this patent

Salt plant evaporation

Life of this patent

Abstract

Claims26