INTERNATIONAL CLEANER PRODUCTION INFORMATION CLEARINGHOUSE

CASE STUDY # 196

1. Headline: Cleaning In Stages

2. Background: See below.

3. Cleaner Production Principle: Process modification

4. Description of Cleaner production Application: Washing

grease off parts was efficiently achieved in three drums

of solvent placed in series. The parts are initially

placed in the first cleaning drum labeled "prewash". The

parts are then removed and placed into the second drum or

the "dirty" drum. The last drum or the "clean" drum will

clean the parts to meet quality standards. As the solvent

solution in the "clean" drum becomes contaminated, it is

transferred to the "dirty" drum. The more spent solution

in the "dirty" drum is transferred to the prewash drum.

Thus, the solution is not disposed of as waste until it

becomes completely spent. This operation produces on the

average a drum of spent solvent every 6.5 days.

Case Study Summary

Incentives: economic incentives

Original Manufacturing Process and Previous Waste/Emission

Management Methods: This facility used to clean parts in

a single 55-gallon drum of solvent. The single drum of

spent solvent had to be changed on the average every 4

days, because it could not clean the parts well enough to

meet quality standards.

Stage of Development: fully implemented

Results of Application: 39% reduction in the amount of

spent solvent generated, 8,700 lb/yr waste prevented.

Effects on Products: the parts are cleaned better

5. Economics

Investment cost: $1,100 (1988)

Payback time: 0.08 years (30

days)

6. Advantages

Wastes generated

55 gal every 4 days (before)

55 gal

every 6.5 days (after)

Economic benefits: 13,400 $/yr net annual savings

Liability reduction: reduced liability resulting from

reduced quantity of waste generated

Regulatory compliance: source reduction

7. Constraints

8. Contacts and Citation

Type of Source Material: Guide

Industry/Program Contact and Address: not provided

Citation:

Author: Waste Advantage, Inc.

Title: Industrial Waste Prevention. A Guide To

Developing An Effective Waste Minimization Program.

Date of Publication: April 1987

9. Keywords United States, USA, cleaning, process

modification, grease, solvent.

10. Reviewer's Comments: This case study was originally

abstracted from the publication cited above for the US

EPA's Pollution Prevention Information Clearinghouse. It

underwent a UNEP IE funded review in 1994 for quality and

completeness. It was edited for the ICPIC diskette in

July 1995.

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