INTERNATIONAL CLEANER PRODUCTION INFORMATION CLEARINGHOUSE

Case Study #277

1.   Headline:  Process modification in a automobile component
     factory reduces toxicity risks for workers.

2.   Background:  The Paulstra firm manufactures elastic joints
     in rubber and metal for automobile anti-vibratory
     components.  Production of 31 millions of pieces in 1992;
     an estimated 6 tons of rubber and 9 tons of steel used per
     day.  Within the framework of its security and environment
     plan, it replaced a chemical stripping of the tools by a
     thermal one.

3.   Cleaner Production Principle:  Process modification.

4.   Description of Cleaner Production Application:

    Information about the process and wastes

     The adhesive coating equipment must be strongly stripped
     after each operation, with trichlorethylene. This
     operation generates toxicity risks for the workmen and
     accidental pollution risks during the handling of the
     products.

     The thermal stripping offers a cheaper and less harmful
     solution.

     A fluidized bed kiln, gas heating combined with an
     afterburner for the fumes was set up. The tools for
     stripping heated about 450C in a tub with an horizontal
     porous base plate which supports sand and which the
     fluidization air flow go through. There is no overheating
     risk, therefore no buckling nor oxidation risk. Stripping
     results from the thermal decomposition of the organic
     constituents. Shaking and brushing make it easier to take
     down the last residual particles. The gaseous discharges
     are according to the environmental norms. The kiln
     generates small quantities of fly ash which must be stored
     in a special dump.

    Material / energy balance and substitution


BEFORE
                                                  AFTER

    Trichlorethylene consumption     42 tons/year     0
    Energy (natural gas)            200 000 kwh/year

5.   Economics:

     Cost of direct investment

Fluidized bed kiln                                       375
                                        000
Handling device                                           33
                                        000
Gas feed device and smoke treatments     33 000
Tests and others                                          34
                                        000
Total
                                        481 000   FF (1993)

    Operation and maintenance costs

Estimated operation costs         80 000/year
Saving on trichlorethylene       150 000/year FF (1993)

    Period of amortization: About 6.5 years.

6.   Advantages:  No more need for solvents.  No more risk of
     accidental pollution.  Improvement of the working
     conditions.

7.   Constraints:  No information provided.

8.   Contact:

              Agence de l'Eau Loire-Bretagne
              M. SENELIER
              TEL:  33  38.51.73.73

              M. MARTIN
              Responsible for ordnance
              TEL: 33 48.71.14.51

              Fluidized bed kiln from the IPROS firm
              Z.I. Les BÆthunes
              95310 SAINT OUEN L'AUMONE
              TEL: 33 34.64.75.00

              Paulstra
              62, rue Henri Barbusse
              B.P. 239
              18101 VIERZON - France
              TEL: 33 48.71.14.51
              FAX: 33 48.71.73.27

     M. Maton
     M. Chatenet
     Office International de l'Eau
     Direction de la Formation et des Etudes
     rue Edouard Chamberland
     87065 Limoges Cedex, France
     TEL:  33  55114770
     FAX:  33  55777115

9.   Keywords:  France, automobile, automobile part, process
     modification, rubber, iron and steel, stripping,
     trichloroethylene, fluidized bed, solvent, ISIC 3843

10.  This case study was submitted to UNEP IE in 1994 by the
     French Office International de l'Eau. It has not undergone
     a formal technical review.