Unilever's sustainable living plan proves a success

Under its Sustainable Living Plan that drives positive change and sustainable growth, Unilever aims to reduce water consumption and produce products in the most efficient way. Yet in one of the company’s liquid plants where reverse osmosis (RO) was in operation, a high proportion of raw water (40,000m³ out of 170,000m³) was being sent to drain.

Only one of the primary RO units at Port Sunlight had been in operation and the reject water from this was being fed to the recovery RO. The resulting permeate was recycled back to the existing soft water tank.

After working with Unilever to understand their objectives, Veolia’s recommended solution was to install its RecoBLUE technology adjacent to the two existing primary RO units. This has the potential to recover 50% of RO wastewater and reduce running costs.  

The pump is controlled by level switches in the buffer tank. When both primary RO units are in service, excess concentrate water (~5m3/h) overflows from the buffer tank to drain.
 

The new plant has increased the overall system recovery from 75% to approximately 85.7%. Unilever is very pleased with the result which saves the company £32k per year, recovers 20,000m3 water annually and is expected to see a return on investment within two and a half years.