Ozone and Food Processing
“Ozone for Treating Water
Food processing plant water can come from various sources including, from a municipality, river or lake. If the water has not been treated, then ozone can be of great assistance. The necessary application rates must be determined according to the impurities present in the influent water. For surface waters, ozone can aid the action of flocculating clays as well as chemical compounds. Filtration can be aided by oxidation of dissolved organic compounds, thus increasing filter run times to backwashing. Ozone can also serve as a disinfectant as the treated water enters the food processing plant.
Ozone for Process Water Recycle & Reuse
For proper treatment of process waters for reuse, attention must be paid to the materials now contained by the process waters. The process water to be recycled and reused should be treated by appropriate procedures, which can include one or more of the following treatment steps: flocculating agents (as necessary to assist removal of organic contaminants and colloidal materials), sedimentation, dissolved air flotation (DAF), filtration, treatment (with ozone) prior to recycling, etc. A significant advantage of ozone is that it saturates the water being treated with oxygen, giving the ozone-treated water a higher optical transmittance.
Ozone for Waste Water Treatment & Disposal
Waste waters from food processing plants usually contain high levels of organic contaminants. These usually are easily biodegradable and as such are amenable to biological waste water treatment. However, this type of treatment requires rather large land areas and time (~ 30 days or more) for completion. Biological treatment is the least costly method of waste water treatment, requiring the least amount of added energy from the food processor. When land is not available, or there is insufficient time for bioprocessing, ozone can provide a technology to reduce BOD and COD levels. Ozone has been shown to aid sludge dewatering, thus aiding filtration. Biotreated effluents can be disinfected with ozone, thus avoiding disinfection with chlorine, and also avoiding the formation of chlorinated organics that pass into the environment and enter the food chain.
Ozone for Washing Foods – Whole or Cut
For this application, water must be very clean and free of organisms. Usually this is not an application for recycled water. However, because of the oxidative properties of ozone, many organic contaminants of food wash waters are destroyed by ozone, allowing the wash water to be used for a longer period of time before disposal. Ozonated wash water for fresh cut salad mixes can later be sent for recycling. Meanwhile, ozone-washed salad mixes can be washed with chlorinated water. It is possible to reduce water use, chlorine use and plant waste water effluent volume simultaneously, resulting in significant cost savings.”
Information from – Ozonize
Ozone and Food Processing