INTERNATIONAL CLEANER PRODUCTION INFORMATION CLEARINGHOUSE

Case Study #262

1.   Headline:  Internal recycling reduces effluent discharge
     in a French concrete plant.

2.   Background:  MatÆriaux DECARPENTRIE operates a plant in
     Gournay-sur-Marne manufacturing ready-to-use concrete,
     producing 76,000 m3 a year. The company has halted their
     effluent discharge by implementing a water and granulates
     recirculation plant.  This case study was carried out in
     1993.

3.   Cleaner Production Principle:  process modification

4.   Description of Cleaner Production Application:

    Information about the process and wastes

     The plant uses 15 000 m3 of water a year withdrawn from
     the channel. The water used for washing the mixing machine
     and the lorries was treated by 2 screws enabling the
     granulates to be recovered; the water which was still
     loaded with concrete fines was settled in 5 tanks in
     series and the sludge sent to the landfill after
     dewatering.

     A new storage tank was fitted with two stirring devices,
     pumps and automatic regulation in order to recirculate the
     water towards the concrete manufacture or the inner
     washing of lorries.

     This facility eliminates any discharge of manufacture
     effluent into the channel.

5.   Economics:

     Cost of direct investment: Total 700 000    FF (1993)

6.   Advantages: Elimination of manufacture discharges.

7.   Constraints:  No information provided.

8.   Contacts:

              Agence de l'Eau Seine-Normandie
              Mlle MATHIEU
              TEL: 33 41.20.16.23

              M. DECARPENTRIE
              18 bis Promenade Marx Dormoy
              93460 GOURNAY-SUR-MARNE - France
              TEL: 33 43.05.30.30
              FAX: 33 43.05.24.97

     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, concrete, process modification, water
     recycling, ISIC 3692, ISIC 5000

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.