Claims
- 1. In a method of purifying product by a freeze crystallization process wherein:
- feed liquor is fed to a first stage comprising a freezer crystallizer and a wash column to produce first product crystals and a first concentrate;
- first concentrate is fed to a second stage freezer crystallizer to produce a slurry comprising second product crystals and a second concentrate;
- the slurry is fed to a second stage wash column having means for supplying a wash liquid to said second product crystals, said liquid consisting of said first concentrate, and an exit screen for removing the second concentrate;
- supplying the wash liquid to the second product crystals situated above the screen in the second stage wash column and forming a wash liquid second concentrate interface above the screen so that the second concentrate completely covers the exit screen; and
- removing the second concentrate and product crystals from the second stage wash column.
- 2. A method of purifying product as described in claim 1 where the product is water.
- 3. A method of purifying product as described in claim 1 which includes the additional step of removing suspended solids from the slurry.
Parent Case Info
This is a division of application Ser. No. 345,427 filed Mar. 27, 1973, now U.S. Pat. No. 3,885,399.
US Referenced Citations (3)
Divisions (1)
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Number |
Date |
Country |
Parent |
345427 |
Mar 1973 |
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