3 Tips for Squeezing More Value from Process Wastewater

When you comply with the regulations for safely manufacturing, distributing and selling your food products, and you’re constantly optimizing your manufacturing process, you might ask ‘What’s left?’ Where can you squeeze out more value and reduce costs? Wastewater could be the answer.

1 – Optimize wastewater flows

A food processing facility generates wastewater throughout the day, but during product changeover or sanitation cycles, wastewater volume and wastewater characteristics can change quickly.

For more information read: How to Manage Your High Strength Wastewater.

In fact, during sanitation, a facility may discharge up to 80 percent of its daily wastewater flow in a four- to six-hour period. Wastewater characteristics like organic strength, temperature, acidity and toxicity also change. Downstream technologies (such as flow equalization, pH adjustment and pretreatment) can help mitigate these conditions. But mitigation measures can be costly and consume profit margin.

What can you do?

Look upstream. Work to identify ways to reduce wastewater flows by opting for clean-in-place program intervals based on scientific, demonstrated results. SEH Senior Wastewater Engineer Kevin Christensen says working with your quality assurance/quality control team, machine operators, control logic programmers and process equipment suppliers is an effective way to determine precise requirements for sanitation processes. Once standard processes are developed, use automated sensors and controls to lock down procedures and take the guesswork out of the process. You are likely to see real cost savings from reduced reliance on sanitation chemicals and reduced wastewater volumes.

2 – Understand Your Process Wastewater

Because its composition is highly variable, understanding your process wastewater requires data gathered at various times and locations. But how do you get the data? Install temporary flow meters and selective samplers to collect wastewater from primary points of generation within your facility. Consider sampling discharge lines from processing machines or waste collection pits to track flow volume and waste strength trends.

        

Review changes in your wastewater composition over time. If the data warrants, evaluate options to retrofit your system to segregate the highest strength waste for alternate management or disposal. Recent studies completed at beverage bottling operations have shown that approximately 60 percent of the biochemical oxygen demand (BOD) can be captured in the first 90 seconds of a system flush. This is important because a relatively small volume of captured wastewater will contain a majority of the waste strength, potentially translating into a reduced, or focused capital investment for wastewater treatment. It can be more cost effective to treat a smaller volume of concentrated wastewater, than to install a wastewater treatment system to treat a large volume of low strength wastewater.

3 – Capture process wastewater for re-use

Does your process wastewater exhibit periods of relatively low organic or chemical impacts? If your facility has non-critical operations, you may be able to safely reuse wastewater in those processes. Rick Viviani, SEH Food & Beverage Manager notes a plant’s final sanitation rinse can be suitable to use as a first flush during product changeover or sanitation.

If it can’t be used in the sanitation process, can it be used elsewhere in the facility? Some processors reuse low strength wastewater as floor wash down. And if it’s clean enough, consider whether bypass of on-site pretreatment, discharge to final effluent or direct discharge to the municipality is feasible.

wastewater treatment facility
Reusing manufacturing wastewater can help facilities save money and optimize their processes.

Wrapping it up

A comprehensive answer will likely be different for each facility and for each processing line within a facility. The key is to strike a balance between processing protocol (with appropriate safeguards) and process wastewater efficiency. The best solution will ensure product safety and processing reliability, generate a minimum of process wastewater and deliver an acceptable return on investment.

About the Experts

Kevin Christensen

Kevin Christensen is a senior wastewater engineer who specializes in helping food processors develop water and wastewater solutions that save money and add value. Contact Kevin

Rick Viviani

Rick Viviani manages SEH’s Food and Beverage team and helps connect clients with SEH’s technical solutions providers. Contact Rick

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