Your sanitation can be greener

Everything’s going green these days, and plant sanitation is no exception. The traditionally chemical-heavy processes that kill the bugs (full-size and microscopic) are particularly fertile ground for more environmentally friendly practices.

There are two key questions every plant manager or maintenance supervisor needs to ask himself: Are there chemicals in the sanitation process that can be replaced with greener ones? If not, can we use less of them with the same results?

Green often is the result of small improvements multiplied. Something as simple as hand washing can be both ineffective and inefficient. But why automate hand washing?

“When you wash your hands, soap is often dispensed into the hands before the water is even turned on. The result is most of the soap is washed down the drain before washing even begins,” says Rebecca Yaffe, director of marketing at Meritech Inc., Golden, Colo. “In addition, it’s easy to use more water than is needed or to get distracted as the water pours down the drain.”

Meritech’s handwashing systems automatically wash, rinse and sanitize hands in a touch-free, germ-killing cycle that begins when an employee puts her hands into the machine and ends after 10 seconds. Manual hand washing can take as long as 1-2 minutes to achieve the same level of protection as the 10-second automated system. “So you may use twice the soap and water without achieving better results,” says Yaffe.

Ozone can replace chlorine, hot water and steam in sanitation programs and it’s safely generated on site.

The result is 75 percent less soap and water used ... and 75 percent less waste water.

Clean-in-place (CIP) once was a process looked at simply as flushing out the pipes. Nowadays, more precise measurement and control of the CIP process assures the right amounts of cleaning solutions are used and that they have been completely removed before the next processing run. “Optimizing these processes not only enhances product quality, it also allows reduced water usage, energy reduction and easier quality control when water is returned to the environment,” says Dave Anderson, food and beverage industry manager at Emerson Process Management’s Rosemount Analytical Liquid division.

Rosemount is an advocate of conductivity analysis. “Since the various cleaning solutions are more conductive than the water used for flushing, conductivity is a reliable and cost-effective measuring technique,” Anderson explains.

Conductivity plays a role in two CIP stages. “To provide detergent of the proper concentration, conductivity measurement is applied to the returning acid and caustic. These conductivity measurements are proportional to concentration or solution strength and are recorded by control systems for validation,” he says.

“Conductivity also plays a key role in the CIP/process interface and final rinsing. It detects very accurately the interface between the cleaning solutions, rinse water and the product phases so that valves can be switched at the appropriate time to minimize product loss and maximize uptime. It also accurately determines the interface between cleaning fluids and rinse water. Faster changes from the cleaning and rinse phases result in less chemical usage and less water treatment, an environmental boon,” Anderson concludes.

Try something different

Ozone is a naturally occurring compound in which three atoms of oxygen combine to form the ozone molecule (O3). Because it’s a highly unstable molecule, due to the weak bond holding the third oxygen atom, it’s a powerful – and short-lived – oxidizing and disinfecting agent.

Sanitation occurs when the unstable third oxygen atom is transferred, with a large release of energy, from ozone to the molecule being oxidized. The transfer of energy in oxidation causes the outer membranes of microorganisms to rupture. As ozone molecules enter lysed microorganisms, genetic material (DNA and RNA) is oxidized and destroyed.

Oxidation typically hydrolyzes inorganic molecules, causing them to become insoluble, and facilitating removal by filtration. Organic molecules most often disintegrate as a result of oxidation.

“Ozone can replace chlorine, hot water and steam in many applications, thereby reducing the consumption of [materials and energy],” says Bob Smith-McCollum, vice president of marketing at Pacific Ozone, Benicia, Calif. That reduction in water use is may become huge in coming years, as water shortage are just becoming an issue of concern to many communities.

“Ozone greatly reduces the environmental burden and risks associated with traditional oxidants, such as chlorine. Ozone resolves to elemental oxygen (O2) and produces few hazardous or undesirable byproducts. Further, ozone is produced on demand at the site of the application and used immediately, thus eliminating the danger of accidental releases of traditional oxidants in transportation and storage.”