More safety with energy chains in the Nice wastewater treatment plant

• What was needed: E2 family energy chain, 316 stainless steel guide trough, chainflex® cable with TPE outer jacket, 316 stainless steel floating moving end
• Requirements: heavy load due to continuous operation of the plant, highly corrosive environmental conditions
• Industry: sewage treatment plant
• Success for the customer: maintenance-free energy supply system with long service life

The wastewater treatment plant, which was built in 1988 on a 3.5-hectare site, is home to numerous innovations. It is responsible for the wastewater of around 500,000 inhabitants of the towns of Nice, Saint-Jean-Cap-Ferrat, Beaulieu and Villefranche-sur-Mer. It operates 10 sedimentation tanks, each with a surface area of 10 x 25 metres for primary treatment, and 12 secondary clarifiers, each measuring 12 x 60 metres. A total of 45 people work on the site, including 15 in eight-hour shifts. The plant is operated all year round. Mistakes are not allowed to happen, as all the beaches in the area have the "Pavillon Bleu", the sign for the certification of clear bathing water. The water leaving the treatment plant is therefore subject to very strict standards.
For the electrical supply to the 10 bridges of the 25 metre long sedimentation tanks and the 12 bridges of the 60 metre long secondary clarifiers, a classic loop system was initially used for the energy supply, in which the flat cables were attached to ball-bearing slides and travelled back and forth on a fixed rail. The first carriage was connected to the bridge and the whole system followed the movements of the bridge. Due to the difficult environmental conditions and the constant work of the bridges, Jean Camilla had to service the carriages of all the basins on a monthly basis. This time-consuming and labour-intensive work also led to costly spare parts management and frequent process interruptions.

This is why the technical arguments and the advantages of the readychain® solutions proposed by igus® for the energy supply of the total of 22 bridges particularly appealed to the operators. The standard chains of the E2 family are made of plastic and are therefore insensitive to corrosion. They have a long service life and are maintenance-free. The first readychain® system from igus® was tested on site for a year before the decision was made to equip all HALIOTIS basins with cable carrier systems from igus® following the successful test run.
The solution also consists of a 316 stainless steel guide trough with an open bottom to facilitate cleaning and 316 stainless steel mounting brackets, which are designed to compensate for misalignments in the building infrastructure and allow for quick installation on site.
The various cables in the e-chain® are well protected, the movements are fluid and a lot of space has been saved. With the highly flexible chainflex® cables, which are specially designed for use in energy chains, millions of work cycles can be carried out without maintenance. Cables with a TPE outer jacket were provided for the sewage treatment plant. These are particularly suitable for dynamic applications and are resistant to oil and dirt. The floating moving end was also made from corrosion-free steel to ensure reliable operation of the system. This part, specially designed by the igus® design office, compensates for the slight misalignment of the rail during the movements of the bridge.