Water and detergent recovery from rinsing water in an industrial environment

Wash water streams coming from rinsing of equipment in a detergent production site is in many cases considered as waste. On site treatment in waste water plants is possible but typically requires advanced oxidation process (AOP) technology which uses chemicals and creates a waste sludge. A new treatment approach, based on nanofiltration, has been demonstrated at industrial scale in a detergent production site in China. Wash water could be split into a concentrate stream and water fraction. The concentrate stream contains most of the valuable surfactants and has a value to recycle. The water fraction can easily be polished by MBR to feed cooling towers. As such, this production site does not discharge any process wash water and recovers all resources out of the rinsing water: both chemicals (as surfactants) as the water.