GEA CIP Recovery Unit

As lowering our overall environmental impact becomes increasingly important, there is growing pressure on industry to reduce the amount of process wastewater that’s discharged to sewers. Having to treat higher volumes of this wastewater can, however, be expensive. 

Most industries have already reduced their water consumption to a minimum. However, even with the implementation of efficient clean-in-place (CIP) systems and the ability to recycle detergents a number of times, large volumes of caustic wastewater are often generated. 

With repeated use, cleaning solutions — which mainly consist of a 2–4 percent sodium hydroxide solution — become loaded with impurities, such as proteins, sugars and colorants, and must subsequently be changed. However, using a nanofiltration (NF) plant from GEA, these solutions can be cleaned and regenerated for continued use, thereby saving money and avoiding disposal issues.

The regeneration of these CIP solutions is achieved using membrane filtration at the normal operating temperature of the fluid (up to 70 °C). The contaminated CIP solution is fed into the main storage tank via a bypass system and subjected to ultrafiltration (UF). This removes suspended colloidal impurities.

Often, CIP solutions can be directly treated in a nanofiltration (NF) system to remove color and low-molecular weight impurities. This concentrates the impurities in the retentate, thereby allowing the purified caustic solution permeate to pass through at the same concentration and temperature as the feed.