Distillation system and process

• US 4,783,242 A
• Filed: 05/22/1986
• Issued: 11/08/1988
• Est. Priority Date: 05/22/1986
• Status: Expired due to Fees

• Current Assignee: The Dow Chemical Company (Dow, Inc.)
• Original Assignee: The Dow Chemical Company (Dow, Inc.)
• Inventors: Robbins, Lanny A.
• Primary Examiner(s): Lacey, David L.
• Assistant Examiner(s): Manoharan, V.
• Application Number:
  US06/866,176
• Time in Patent Office: 901 Days
• Field of Search: 203/87, 203/88, 203/95, 203/96, 203/97, 203/98, 203/91-94, 203/12, 202/177, 202/176, 202/186, 202/199, 202/204, 202/205, 202/198, 159/2.1, 159/24.3, 159/47.1, 159/DIG. 16
• US Class Current: 203/87
• CPC Class Codes: B01D 1/2856 The compressed vapour is used for heating a reboiler or a heat exchanger outside an evaporator
• CPC Class Codes: B01D 3/06 Flash distillation
• CPC Class Codes: B01D 3/14 Fractional distillation or use of a fractionation or rectification column
• CPC Class Codes: B01D 3/322 Reboiler specifications
• CPC Class Codes: B01D 3/38 Steam distillation
• CPC Class Codes: B01D 5/00 Condensation of vapours; Recovering volatile solvents by condensation B01D8/00 takes precedence; condensers F28B

Abstract

A distillation system and process for removing vaporizable components from an aqueous medium including a distillation column for receiving an aqueous medium containing vaporizable components and passing steam through the column such that the steam directly contacts the aqueous medium to vaporize at least a portion of the components, a condenser in a communication with the column to condense at least a portion of the vapor in the column, a separator in communication with the condenser to separate flash vapor from liquid condensate in the separator and a thermal compressor in communication with the separator and the column to remove vapor from the separator and to inject exhaust steam from the thermal compressor into the column.

Claims

1. A distillation process for removing vaporizable components from an aqueous medium comprising:

a. introducing an aqueous medium containing vaporizable components into a distillation column for removing a portion of the vaporizable components from the aqueous medium.

b. passing through the aqueous medium a current of steam from a thermal compressor to vaporize at least a portion of the vaporizable components,

c. passing at least a portion of the vapors from the distillation column through a first space of a first condenser means having a first and second space sufficient to condense at least a portion of the vapors to a condensate.

d. passing a recirculation liquid to the second space of the condenser means and from the condenser to a separator to separate steam from aqueous liquid, and

e. passing the steam from the separator through the thermal compressor to form steam for introducing into the distillation column.

2. The process of claim 1 including passing the vapors from the first condenser means through a second condenser means to condense substantially all of the vapors.

3. The process of claim 2 including recycling at least a portion of the condensed vapors from the second condenser means to the distillation column.

4. The process of claim 2 including passing the condensed vapors from the second condenser means to a decanting means to separate at least two liquids.

5. The process of claim 4 including recycling at least a portion of at least one liquid from the decanting means to the distillation column.

6. The process of claim 1 including preheating the aqueous medium in a preheater means prior to introducing the aqueous medium to the distillation column.

7. The process of claim 6 including passing at least a portion of the recirculation fluid to the preheater means for preheating the aqueous medium.

8. The process of claim 1 including passing a bottom stream from the distillation column to the separator.

9. The process of claim 1 including recycling at least a portion of the aqueous condensate from the first condenser means to the distillation column.

10. The process of claim 1 including adding an aqueous make-up stream to the recirculation fluid stream.