US 6,306,197 B1 · Isopropyl alcohol scrubbing system

Abstract

A system and method for treating process gas streams containing isopropyl alcohol (IPA) to reduce the concentration of IPA therein. The invented system includes a scrubber unit that receives a process stream containing a concentration of IPA and reduces the concentration of IPA therein to below a determined threshold. The scrubber includes a reverse osmosis assembly that significantly reduces water consumption for the scrubbing process as compared to conventional once-through systems. The system may be operated at an elevated pH to prevent biofouling from inhibiting the operation of the reverse osmosis assembly. The system may contain a softening step on the make up water system to prevent scaling in the reverse osmosis system and a softening step on a sidestream of the scrubber water recirculation loop to reduce scrubber tower salting/scaling and to control the pH of the scrubbing liquid.

Claims33

Dependent claims

A gas phase isopropyl alcohol (IPA) removal system, comprising:

a scrubber unit having a liquid sump portion and a liquid recirculation portion and adapted to receive and contact a gas feed stream containing a concentration of IPA with a water stream;
a pump assembly adapted to draw a recirculation stream from the liquid sump portion of the scrubber unit and deliver the recirculation stream to the return portion of the scrubber unit, wherein the recirculation stream contains at least a portion of the IPA in the feed stream;
and
a reverse osmosis assembly including at least one reverse osmosis unit adapted to receive the recirculation stream prior to delivery to the return portion of the scrubber unit and to reduce the concentration of IPA therein to below a determined threshold value to form a waste stream containing the removed IPA.

1 more element

Dependencies are inferred from the claim text.

Isopropyl alcohol scrubbing system

Life of this patent

Isopropyl alcohol scrubbing system

Life of this patent

Abstract

Claims33