CIP

Tank outlet configuration on three channel CIP set

A wide range of CIP detergents and disinfectants are available. One common feature to all is that the products are low foaming and in some circumstances act as defoamers. This is particularly important where caustic detergents are used to remove fatty deposits. The reaction between the caustic and fats produces soap which will naturally foam in recirculation situations.

The choice of detergent and disinfectant are based primarily on the soil types and micro-organisms of concern. In general most modern production systems are constructed of stainless steel with a variety of polymers used as seal materials. This and the fact that during cleaning operatives are not exposed to the cleaning solutions allow the use of highly alkaline or highly acidic products.

With highly caustic products sequestration is important for control of mineral scale drop out from water hardness. With certain processes the removal of soils containing high levels of calcium (for instance milk based proteins) is greatly improved by the use of specific sequestrants. In many CIP situations a caustic based, low foam, detergent is used at typically 0.25% to 1% w/v (NaOH) at 65 to 75ºC.

When caustic cleaning of vessels, containing CO2, the caustic reacts and is converted to sodium carbonate reducing the detergency of the solution. Acid cleaning of process vessels is used with benefit where CO2 is present from the process (soft drinks and brewing).

Disinfectants used are generally, although not always, very low foaming and commonly oxidising disinfectants such as peracetic acid or sodium hypochlorite.