Water desalination system and method for fast cooling saline water using turbines

Patent metadata

Field	Value
Publication number	US-2017190597-A1
Application number	US-201514983658-A
Country	US
Kind code	A1
Filing date	Dec 30, 2015
Priority date	Dec 30, 2015
Publication date	Jul 6, 2017
Grant date	—

Abstract

A desalinating system and method is disclosed. The desalination system comprises using a turbo freeze or fast-cooling process to freeze saline water droplets and separate salt crystals from pure water crystals, wherein said system provides for simultaneous injection of saline water droplets and a chilled refrigerant into a freezing chamber at a slip velocity sufficient to reduce the size of the saline water droplets to an optimal diameter.

First claim

1 . A system for desalination comprising:
a feed source of saline water; a feed source of at least one refrigerant; a compressor, comprising an input fluidly coupled to the source of said at least one refrigerant and an output, and configured to generate a compressed vaporized refrigerant; a condenser comprising an input fluidly coupled to the compressor and an output, said condenser operatively configured to generate a chilled, partially liquefied refrigerant stream; at least one expansion device comprising at least one input fluidly coupled to the condenser and at least one output configured to release the chilled refrigerant stream at a refrigerant stream injection velocity; a freezing chamber comprising at least one input to introduce the chilled refrigerant stream into the chamber, and a first, second and third output, and at least one injector configured to introduce the saline water into the freezing chamber in the form of saline water droplets, wherein the at least one ejector introduces the saline water droplets into the freezing chamber at a slip injection velocity relative to the refrigerant stream injection velocity of about 10% to about 180%; and wherein direct contact in the chamber between the saline water droplets and the refrigerant stream forms ice particles comprising pure water.

2 . The system of claim 1 , wherein the at least one expansion device is a two-stage turbo expander.

3 . The system of claim 2 , wherein the turbo expander is adapted to function as the freezing chamber.

4 . The system of claim 2 , wherein the freezing chamber is a separate crystallization tank.

5 . The system of claim 1 , wherein the at least one injector is a sprayer comprising a nozzle operatively configured to introduce saline water droplets with an initial diameter (d i ) in the range of about 200 microns (μ) to about 1000 microns (μ) into the freezing chamber.

6 . The system of claim 1 , wherein the at least one ejector introduces the saline water droplets into the freezing chamber at a slip injection velocity relative to the refrigerant stream velocity that is sufficient to achieve saline water droplets with a reduced diameter (d r ) in the range of about 10 microns (μ) to about 50 microns (μ).

7 . The system of claim 1 , wherein the at least one injector introduces saline water droplets into the freezing chamber at a slip injection velocity in the range of about 48% to about 120%

8 . The system of claim 7 , wherein the at least one injector introduces saline water droplets into the freezing chamber at a slip injection velocity of about 90%.

9 . The system of claim 1 , wherein flow of the saline water droplets through the freezing chamber is in parallel flow relationship with and in the same direction as the refrigerant stream through the freezing chamber.

10 . The system of claim 1 , wherein flow of the saline water droplets through the freezing chamber is in cross-flow relationship to the refrigerant stream through the freezing chamber.

11 . The system of claim 1 , wherein the at least one refrigerant is selected from the group consisting of a hydrocarbon, ammonia, chlorine-containing carbon compounds, and fluorine-containing carbon compounds.

12 . The system of claim 11 , wherein the hydrocarbon comprises propane, isopentane, butane, iso-butane, pentane and mixtures thereof.

13 . The system of claim 1 , wherein the temperature of the refrigerant stream in the freezing chamber is in the range of about 0° C. to about −50° C., more preferably in the range of 0° C. to about −20° C., and most preferably about −20° C.

14 . The system of claim 1 , wherein the first output of the freezing chamber is connected to a salt collector for collecting salt crystals, the second output of the freezing chamber is connected to an ice collector for collecting ice particles, and the third output is fluidly coupled to the compressor to create a closed circuit for the refrigerant stream.

15 . The system of claim 14 , wherein the condenser is an ice melter fluidly connected to the ice collector and operatively configured to melt the ice particles to produce water containing no or essentially no salt and to condense the refrigerant stream by indirect heat exchange.

16 . The system of claim 2 , further characterized by one of the following: (a) said compressor, condenser, and turbo expander operatively are connected in a closed series relation to create a closed system and the at least one refrigerant circulates in the closed circuit; or (b) said compressor, condenser, turbo expander, and freezing chamber operatively are connected in a closed series relation to create a closed system and the at least one refrigerant circulates in the closed system.

17 . The system of claim 2 , further comprising at least one of the following:
a. an ice separator; b. a solid/vapor separator; c. a salt/vapor separator; d. a device to mechanically remove ice particles from the freezing chamber; e. a pump configured to compress the saline water stream prior to introduction into the at least one nozzle; f. a storage tank fluidly connected to the ice melter that stores pured water derived from the ice particles; g. an air cooler to cool the compressed refrigerant stream; h. at least one heat exchanger configured to cool the compressed refrigerant stream after it exits the air cooler; i. a second heat exchanger configured to cool the saline water stream before injection into the chamber; and j. a controller operable to control the desalination system.

18 . A desalination system comprising:
a compressor, a turbo expander, and a freezing chamber, said compressor, said turbo expander and the freezing chamber connected in a closed system to circulate a refrigerant stream; and an injector configured to introduce simultaneously into the freezing chamber the refrigerant stream and a saline water stream in the form of saline water droplets, wherein the refrigerant stream has a predetermined velocity and the saline water droplets have an initial diameter (d i ) of less than about 1 millimeter (mm) and are introduced at a slip velocity ratio of about 90% relative to the refrigerant stream velocity; and wherein direct contact between the saline water droplets and the refrigerant stream in the freezing chamber forms ice particles comprising purified water within about 10 microseconds (ms) to about 300 microseconds (ms).

19 . The desalination system of claim 18 further comprising a condenser, wherein the condenser is an ice melter configured to melt the ice particles and generate a partially liquefied, chilled refrigerant stream via indirect heat exchange, and the system is configured for use in a continuous manner for purifying saline water.

20 . The system of claim 19 , wherein the at least one refrigerant is selected from the group consisting of a hydrocarbon, ammonia, chlorine-containing carbon compounds, and fluorine-containing carbon compounds.

21 . The system of claim 18 , wherein the at least one refrigerant is air.

22 . A desalinating process, comprising the steps of:
(a) providing at least one refrigerant and a feed source of saline water; (b) compressing the at least one refrigerant to generate a partially liquefied, chilled refrigerant stream; (d) expanding the refrigerant stream through an expansion device; (e) injecting the saline water into a freezing chamber in the form of water droplets, wherein said saline water droplets have an initial diameter (d i ) of less than

Assignees

• Gen Electric

Inventors

• Lissianski Vitali Victor
• Hofer Douglas Carl
• Osaheni John Aibangbee
• Singh Rajkeshar
• Laursen Anna Lis
• Moraga Francisco J

Classifications

• B01D9/0059

  General arrangements of crystallisation plant, e.g. flow sheets · CPC title

• B01D9/0009

  by direct heat exchange with added cooling fluid · CPC title

• C02F2103/08

  Seawater, e.g. for desalination · CPC title

• C02F1/22 Primary

  by freezing · CPC title

• C02F2101/10

  Inorganic compounds · CPC title