Disinfection with CIP
Cleaning-in-place (CIP) systems clean pipelines, tanks, heat exchangers, centrifuges and homogenizers without dismantling the equipment. The degree of automation and the cleaning sequence depend on the equipment and cleaning requirements.
A typical sequence may include:
- Initial flushing
- Alkaline cleaning with a caustic detergent
- Intermediate water rinse
- Acid cleaning, where required
- Final water rinse
Detergent selection depends on the deposits to be removed, the materials being cleaned and operating costs. Cleaning and disinfection are separate tasks: a caustic wash alone does not establish that equipment is disinfected or sterile. When disinfection is required, a validated sanitizing step follows cleaning.
Ozone, chlorine dioxide and hydrogen peroxide are among the chemicals used for disinfection. Their suitability depends on concentration, contact time, temperature, water quality and compatibility with equipment materials.
Comparison of chemical sanitizers
| Consideration | Ozone | Chlorine dioxide | Hydrogen peroxide |
|---|---|---|---|
| Properties and potential benefits | A strong oxidant generated on site. It can disinfect cleaned equipment when the operating conditions are appropriate. | An oxidizing disinfectant. Its performance and by-product formation depend on water quality and operating conditions. | An oxidizing disinfectant whose antimicrobial activity can be enhanced by combining it with peracetic acid. |
| Operating considerations | Residual dissolved ozone may remain in the water leaving the equipment. Generation, handling and exposure require appropriate controls. | Chlorite and chlorate by-products require control. Material compatibility, including compatibility with stainless steel, must be assessed. | Concentrated hydrogen peroxide requires appropriate handling and material-compatibility checks. Residual disinfectant must be managed according to the process requirements. |
Follow the disinfectant supplier's instructions and validate the cleaning and disinfection procedure for the intended application.