PROJECT DESCRIPTION
BACKGROUND
The Maubeuge Construction Automobile (MCA) is one of the main Renault factories. The site is spread over 40 ha of waterproof surfaces (roofs and tarmac). The water needs for different industrial processes are equivalent to that required by a small town with 10.000 inhabitants, eg 550 000 m3 per year. Significantly, it is estimated that in France, 50% of the total pollution of water is caused by rain water. Since 1995, a local authority regulation (new national legislation) applied to the MCA plant includes requirements about the quality of the rain discharges. MCA was one of the first industrial sites of the RENAULT group to be submitted to the requirements of this regulation. Furthermore, the Renault group had undertaken a diagnosis of its water networks and discharges on several of it's sites. The results of the assessment showed that the pollution level for a plant like MCA was similar to an area in-between suburb and down-town. The monitoring of rain showers revealed that the Solids in Suspension (SS) and the Chemical Oxygen Demand (COD) were above the requirements. The conclusions were : 1. Prevention of industrial pollution at the source is not sufficient to meet the requirements. A strategy for diminishing the water consumption should be set-up in parallel with the preparation of a recycling project. 2. The building of basins or natural decanting is the best available technology at an acceptable cost, to meet the requirements. On the MCA plant, the cost of water was very high, since drinking water was the only source : with 550 000 m3 of water utilised in 1996, the annual bill was 400 000 EUR.
OBJECTIVES
The project aimed to demonstrate the technical feasibility and profitability of reusing industrial rainwater for industrial processes. This included : - The realisation of a stormwater reuse system on a demonstration site of the car industry. - The demonstration of the feasibility and stability of its performance for the reuse of treated water in industrial processes. - From data collected on eight other demonstration sites, the development of a model and a software to evaluate the technical feasability and calculate the profitability of stormwater reuse. The model must be transferable to any other industry.
RESULTS
The various steps of the project involved: - building and operating a stormwater reuse system (collection, storage, treatment and distribution of treated water) on the MCA site (body and car assembly). A simple and classical method for water purification was put into operation, since the water was required for industrial use. - development of a model of the on-site stormwater reuse to assess the technical feasability and calculate the profitability of such a system (including technical and economic aspects); development of the associated software, - transferability of the model to other types of industrial sites (i.e to other site-specific pollution, such as foundry and mechanical manufacturing), - utilisation of the software on other sites (assessment of technical feasability, calculation of profitability and system acceptance by users) . The MCA project can be considered a complete success. From an environmental point of view, its benefits are twofold : - It reduces the quantity of drinking water used by the plant. 160 000 m3 of water were recycled from rain water in 2000, representing a savings of 50 000 EUR, which covers the production cost. - It reduces the quantity of polluted rain water that goes into rivers. Yet, this impact is limited to the 40 ha of the factory, which is a very small surface in comparison with the scale of the town of Maubeuge. One of « teething » problems encountered was the reluctance of the users in the workshops to use the recycled water. The quality of water is very important for a series of operations such as painting the bodies of the cars : a problem with water quality can lead to stopping the production chain, maybe for a few hours. Since the production is one car per minute, this means a loss of 10 to 20 000 EUR per minute. The factory aims to reach 200 000 m3 with some further work and adjustments. This is necessary to gain the certification ISO 14001 that is the target for 2003. The Renault group has set a target to use 20% of rain water in all its factories by the year 2010. Hence, the MCA experience was used to develop a specific software (SIRRUS : Software for Industrial Rainwater ReUse), which answers the question : « Can recycling rain water be profitable in my factory ? ». This software was developed and tested in three other sites of the Renault group (the test planned in Vilvoorde (B) had to be cancelled due to the closure of the factory). The answer was « yes » for all three sites, which means that Renault will transfer this method to these other sites. The various steps of the project involved: - building and operating a stormwater reuse system (collection, storage, treatment and distribution of treated water) on the MCA site (body and car assembly). A simple and classical method for water purification was put into operation, since the water was required for industrial use. - development of a model of the on-site stormwater reuse to assess the technical feasability and calculate the profitability of such a system (including technical and economic aspects); development of the associated software, - transferability of the model to other types of industrial sites (i.e to other site-specific pollution, such as foundry and mechanical manufacturing), - utilisation of the software on other sites (assessment of technical feasability, calculation of profitability and system acceptance by users) . The MCA project can be considered a complete success. From an environmental point of view, its benefits are twofold : - It reduces the quantity of drinking water used by the plant. 160 000 m3 of water were recycled from rain water in 2000, representing a savings of 50 000 EUR, which covers the production cost. - It reduces the quantity of polluted rain water that goes into rivers. Yet, this impact is limited to the 40 ha of the factory, which is a very small surface in comparison with the scale of the town of Maubeuge. One of « teething » problems encountered was the reluctance of the users in the workshops to use the recycled water. The quality of water is very important for a series of operations such as painting the bodies of the cars : a problem with water quality can lead to stopping the production chain, maybe for a few hours. Since the production is one car per minute, this means a loss of 10 to 20 000 EUR per minute. The factory aims to reach 200 000 m3 with some further work and adjustments. This is necessary to gain the certification ISO 14001 that is the target for 2003. The Renault group has set a target to use 20% of rain water in all its factories by the year 2010. Hence, the MCA experience was used to develop a specific software (SIRRUS : Software for Industrial Rainwater ReUse), which answers the question : « Can recycling rain water be profitable in my factory ? ». This software was developed and tested in three other sites of the Renault group (the test planned in Vilvoorde (B) had to be cancelled due to the closure of the factory). The answer was « yes » for all three sites, which means that Renault will transfer this method to these other sites.
