CASE STUDY # 91
1. Headline: Improved operating practices in the chemical
industry
2. Background: See below.
3. Cleaner Production Principle: Good housekeeping, improved
operating practices
4. Description of Cleaner Production Application: This
facility uses a closed-loop process water recycling system
to reduce its waste. Texasgulf produces phosphate animal
feed supplement by combining phosphate ore, soda ash, and
phosphoric acid in a kiln mixer. The process produces a
kiln scrubber sump water with a flow rate of 1725 gpm at
108 F. Lime is added at a rate of two tons per hour to
precipitate the fluorides as calcium fluoride. These
filtered/dewatered wastes are disposed in a landfill as a
solid. The clean process water is recycled back to the
venturi scrubbers for reuse.
Material/Energy Balances and Substitutions
FEEDSTOCKS:
Inorganic fluorides
WASTES: Calcium
fluoride, wastewater
MEDIUM: Water
5. Economics
MONTHS TO RECOVER: 12
6. Advantages:
FEEDSTOCK REDUCTION:
$870,000/year (water usage)
WASTE PRODUCTION:
$930,000/year reduction (reduced
280,000 gallons per day
IMPACT: Reduces
water usage, wastewater not
discharged to the environment.
7. Constraints: Information not provided.
8. Contacts and Citation:
"Proven Profit from Pollution Prevention," D. Huisingh, L.
Martin, H. Hilger, N. Seldman, The Institute for
Self-Reliance 2425 18th Street, N.W., Washington, D.C.,
United States, 1985, case study 20, Page 80.
Name and Location of
Company:
Texasgulf
Saltville, VA
United States
9. Keywords: United States, USA, chemical, animal food, good
housekeeping, phosphate, fluoride, ISIC 2878.
10. Reviewer's Comments: This case study was originally
abstracted for the United States Environmental Protection
Agency's Pollution Prevention Information Clearinghouse.
It underwent a UNEP IE funded technical review in 1994 for
quality and completeness. It was edited for the ICPIC
diskette by UNEP IE in July 1995.
(DOCNO: UNEP01.52 306-001-A-024)