Regenerated cellulose softener recovery method and apparatus

• US 3,889,390 A
• Filed: 10/18/1974
• Issued: 06/17/1975
• Est. Priority Date: 10/18/1974
• Status: Expired due to Term

• Current Assignee: KWB Associates II Limited A Georgia Limited Partnership
• Original Assignee: Robert John Klare
• Inventors: Klare, Robert John
• Primary Examiner(s): Sprague, Kenneth W.
• Assistant Examiner(s): Yeung, James C.
• Application Number:
  US05/515,965
• Time in Patent Office: 242 Days
• Field of Search: 34/23,26,27,32,20,72-78,155 68/18R,18C,19,20
• US Class Current: 34/448
• CPC Class Codes: B01D 53/14 by absorption
• CPC Class Codes: B01D 53/1406 Multiple stage absorption
• CPC Class Codes: B01D 53/1418 Recovery of products
• CPC Class Codes: B01D 53/1425 Regeneration of liquid absorbents
• CPC Class Codes: B01D 53/1493 Selection of liquid materials for use as absorbents
• CPC Class Codes: B29C 71/00 After-treatment of articles without altering their shape; Apparatus therefor B29C44/56, B29C73/00 take precedence; surface shaping B29C59/00 ; for joined or sealed parts B29C66/03; after-treatment specially adapted for vulcanising tyres B29D30/0633
• CPC Class Codes: B29D 7/00 Producing flat articles, e.g. films or sheets B29D24/00 takes precedence

Abstract

An improvement in a process for continuously and automatically reclaiming a portion of a softening agent used in treating regenerated cellulose film in which the softening agent is absorbed in two steps from an exhaust air stream and returned directly to the film treating step. A separate dilute aqueous solution of softening agent is used as the absorbent in the second absorption step, and a mist eliminator between the absorption steps controls the movement of resin contaminants within the softener recovery apparatus.

Claims

1. REMOVING ENTRAINED DROPLETS OF AQUEOUS SOLUTION AND SOLID CONTAMINANTS FROM THE AIR STREAM OF THE ABSORPTION STEP (C),

2. The process as defined in claim 1 wherein said aqueous solution of softening agent contains from about 0 to 1.5 weight percent of a urea-formaldehyde resin, which resin is removed in the droplets of step (1) prior to further absorbing step (2).

3. ADDING WATER TO SAID DILUTE AQUEOUS SOLUTION OF SOFTENING AGENT TO REPLACE PROCESS WATER LOSSES.

4. The process as defined in claim 3 wherein said separate dilute aqueous solution of softening agent contains about 1 to 3 weight percent softening agent.

5. In an apparatus for reclaiming a portion of a softening agent used in treating regenerated cellulose film which comprises:

a. a tank for containing an aqueous solution of softening agent with means for moving a gel regenerated cellulose film through said tank;

b. a drying chamber for drying the film from said tank by a stream of air passing therethrough;

c. means for moving the gel regenerated cellulose film through said drying chamber counter current to said air stream so that excess water and softening agent are transferred from said film to said air stream;

d. a first aBsorption chamber for absorbing softening agent from said air stream;

e. means for moving said air stream from said drying chamber to said first absorption chamber;

f. means for dispersing a mist of said aqueous solution of softening agent from said tank into said air stream within said first absorption chamber;

g. means for returning said aqueous solution from said first absorption chamber to said tank;

the improvement which comprises;

6. The apparatus as defined in claim 5 wherein said containing means comprises a reservoir including means for returning excess dilute aqueous solution of softening agent from said reservoir to said tank.

7. The apparatus as defined in claim 6 wherein said mist eliminator is a vane-type mist eliminator.

8. The apparatus as defined in claim 7 wherein said means for dispersing a mist of dilute aqueous solution of softening agent comprises a plurality of full cone spray nozzles.