INTERNATIONAL CLEANER PRODUCTION INFORMATION CLEARINGHOUSE

CASE STUDY # 178

1.             Headline:Recovery of Isopropyl in Textile
               Processing Operations

2.   background:  See below.

3.   Cleaner Production Principle:  Internal recycling, process
     modification

4.   Description of Cleaner Production Application:
     This company purchased its own isopropyl alcohol
     distillation unit to distill its isopropyl alcohol
     on-site.

     Process and Waste Information:  One of the processes used
     by this company in its production was the use of isopropyl
     alcohol as a solvent.  The distillation of waste isopropyl
     was previously done off-site by another company, but this
     practice had several disadvantages.  The average
     distillation losses ranged from 15 to 40 percent.  Also,
     due to improper cleaning of the distillation column during
     the process, the isopropyl alcohol was found to be
     unusable due to contamination.  Thus, each batch of
     recycled isopropyl had to be analyzed for contamination
     and if found unsuitable then disposal arrangements,
     including fees, had to be made.

     American Enka purchased a used distillation unit for US
     $7500 and modified it to redistill isopropyl alcohol
     in-house.  The in-house distillation was found to be more
     efficient and recovered 90 percent of the alcohol, as
     opposed to 85 percent before.  American Enka also utilized
     the still bottoms as an asphalt emulsifier in another
     product line.

     Material/Energy Balances and Substitutions:


Quantity
                                             Quantity

                                             Before
                                             After
Material Category

     Waste Generation:       Information not available
     Feedstock Use:        Recovered 90%       Recovered 85%
     Water Use:              Information not available
     Energy Use:             Information not available

5.    Economics

     Investment Costs: The used distillation unit cost US
     $7500.

     Operational & Maintenance Costs:  American Enka achieved a
     net savings of US $90,000 per year.

     Payback Time:  The payback period for this project was
     less than one month.

6.   Advantages:  Economic benefits include the savings of US
     $90,000 per year.  These savings resulted from to the
     reuse of still bottoms as asphalt emulsifiers and the
     avoided costs of waste disposal.

7.   Constraints:  No information provided.

8.   Contacts and Citation

     Type of Source Material:  Organizational report

     Citation:  "Profits of Pollution Prevention - A Compendium
     of North Carolina Case Studies".  Huisingh, D., et al.
     North Carolina Department of Natural Resources and
     Community Development, May 1985.

9.   Keywords:  textile, textile processing, recycling, process
     modification, isopropyl, solvent, distillation, ISIC 2282.

10.  Reviewer's Comments:  This case study was originally
     compiled by the UNEP Working Group of Textiles.  It
     underwent a UNEP IE funded technical review in 1994 for
     quality and completeness.  It was edited for the ICPIC
     diskette in July of 1995.

( Docno UNEP 11: DOCUMENT NOT AVAILABLE 11-03 )