Peter Harpley — Director Water Treatment & Engineering UKI at Diversey — answers key questions about water — from reduction to reuse, the need for solutions outside of the box, and how a partnership combining water treatment and hygiene is the true synergy for production success.
Q: Why do you believe it is important that the food and beverage sector starts to re-evaluate its use of water, from both a cost and an environmental perspective?
A: The cost of water is increasing as a resource, not only water going into a facility but also the treatment costs associated with wastewater. With regulations becoming ever stricter concerning tolerated levels of contamination in discharged water, we are coming closer to the day that new production facilities will be constructed around water usage. These will be designed to minimize effluent discharge, optimize effluent discharge and minimize water costs.
The increase in water consumption globally is creating a scarcer commodity. This is driving the need to optimize and reduce waste from cleaning processes. Routine washdowns and clean-in-place (CIP) procedures need to become more efficient at minimizing the waste going into water. It will become increasingly important to physically remove waste and detritus that would normally be washed off. Historically wastewater treatment in food processing uses lots of water which then exits down the drain. This will come to a gradual end, with the cost involved making it uncompetitive in these environments.
Q: Water is fundamental to successful and efficient production in many food processing operations. Can you offer any advice on how it is possible to reduce overall water usage without compromising product quality or process efficiency?
A: Reducing overall water usage is a very contentious topic. A future focusing just on reducing the physical use of water disregards the complexity involved, especially when certain food processes are net water generators. A potato processor is a prime example, where the process involves actually taking water out of a product. Consequently, a potato processor's water out will be greater than its water in. Therefore, the emphasis is more on how facilities deal with that water; how they can reuse it — and perhaps provide it to other factories in the area for a future where water is utilized in a far more efficient manner. This could significantly reduce energy consumption from the requirement for treatment in a sewage works, and a return to the environment, before then being retreated to go back into the factory.
However, if you are a processor that is a significant user of water — specifically using more water than your products are giving out — then as you improve your water usage, it is important to reduce any contamination. If you don’t, this may actually cause more problems than any positive outcomes you achieve. When you have a high level of contaminants and a low level of water it can be harder to deal with effectively upon discharge. It’s not necessarily the volume going out but the quality, and here is where collaboration and reuse are key.
As technology in wastewater treatment and recycling evolves from its current relative infancy, it may well be that it’s better to use plenty of water for processes, but with the aim of treating and recycling it yourself. The key is looking at where you can use the water on-site. Diversey recently implemented recycling within a crate washing system. We improved the once through, very inefficient final wash, which has to use potable water that then goes straight to the drain, by treating and guaranteeing it as potable water to be reused as the initial rinse. Any other water used can be put back into the crate washer earlier in the process. The complexity and technology needed to return water like this is often not commercially viable. Nevertheless, it’s possible to identify areas where a big usage of water occurs where it doesn’t have to be potable water.
Q: Where are the easy wins to start making reductions in water consumption in the food factory?
A: Prioritize looking for leaks and inefficiencies, not just in processing halls, but anywhere that water can be potentially wasted. For example, we identified a huge leak of water from a process where water was added to a chemical flocculent used for wastewater treatment. Dealt with inefficiently, this meant significant water was going straight to the drain.
Rigorously look for any leakage from your steam system, reverse osmosis plant and where water systems are affected by scale, which may not just involve traditional towers or boilers.
Q: What tools are available today to help food processors optimize their water management strategy?
A: Much optimization relies on the quality of physical support, experience and expertise a water treatment provider can give you on site. In regard to leaks, AquaCheck and SteamCheck are just two solutions within Diversey Knowledge-Based Services (KBS) that help deliver this vital support.
With the proviso that all sites are different, study where wastewater comes from in your factory. This is not just about chemistry and disinfecting. As stressed, it’s how you reduce the waste in the water that’s key. Can you remove the waste by better processes and physical action prior to washes? This may involve looking at tools outside the box in order to physically remove some of the soiling.
Diversey has used one wash of our Aquaform product for a taint removal process at a bottling plant. This avoids a CIP, and then a post rinse, that each use large volumes of water. By applying clean chemistry you can achieve a considerable water saving. Analyze the bigger picture of whole-site usage, optimization of chemistry and a commitment to do water treatment more efficiently. These should be viewed as hand-in-hand to change perceptions and realize the benefits. With water treatment and hygiene working very closely together, Diversey solved a water recycling issue in a major brewery which also negated hygiene issues they were experiencing.
Synergy is crucial as problems in hygiene are often water-related; not necessarily about water usage but water treatment. That’s why you should look for a partnership where all factors are analyzed in an overall team effort to maximize your results.
