The determining factors of a food plant's ability to handle its wastewater are both internal and external. While a food manufacturer might excel at reducing waste, even as production expands, the municipal system that accepts the waste (or the regulators that limit surface discharge) might tighten restrictions at any time.
Thankfully, food processors can turn to professionals for wastewater treatment solutions providing up to a 60 percent reduction in biological oxygen demand (BOD), the standard measure of waste concentration in wastewater. These companies provide biological solutions that allow a company's current treatment systems to more effectively treat a larger load without a physical expansion.
"As the population continues to grow and food production increases, many municipal treatment facilities are too small to handle what was previously possible," says John Norton, vice president of environmental technology at BioWish Technologies (www.biowishtechnologies.com), Chicago. "Community governments are forced to levy fines to pay for upgrades. Plants that discharge directly to a body of water are being forced to ensure clean policies because of increased environmental awareness."
Careful planning and good communication with municipal officials and other regulators will help avoid emergencies. But when that fails, there are ways to deal with unforeseen problems, Norton says.
"Often, when there is a wastewater situation causing a violation, the fines add up quickly and the plant must find an immediate solution. They simply can't wait to commission an engineering firm, acquire funding and execute the project. In these situations, BioWish is very effective at quickly implementing a solution that can lower BOD, and other factors."
BioWish offers products like Aqua Fog, which is designed to significantly improve the efficiency of aerobic treatment systems. The company says Aqua Fog reduces sludge production and handling by as much as 60 percent. It also reduces energy use, allows for increased plant capacity by reducing contact time of wastewater and eliminates odorous emissions, the company says.
BioWater Technology (www.biowatertechnology.com), Cumberland, R.I., provides combined fixed-film activated sludge treatment systems with applications for a variety of industries including food.
"The food processing industry is a key customer base," says Laura Marcolini, technical director at BioWater. "Food processing facilities such as meat processing, egg washing, fruit processing, beverage bottling and dairy packaging are typical end users of our biofilm treatment processes."
Marcolini concurs that internal and external demands can leave food processors struggling to avoid fines. She notes that a company's reputation can also be at stake.
"The main drivers that prompt food processors to use our biofilm treatment technologies are the need to meet pretreatment or surface discharge regulations," she says. "Ancillary benefits related to use of our treatment processes may include return on investment, reduced carbon footprint, and improved public image."
BioWater installations use dissolved air flotation (DAF) in lieu of a large secondary settling basin or gravity clarifier. The advantages include an extremely small treatment footprint and very low sludge pumping rates, resulting from DAF's ability to generate a thicker sludge blanket than a settling basin.
"BioWater's continuous flow intermittent cleaning (CFIC) process provides the benefit of controlled wasting of solids and reduced energy costs," Marcolini says. Those along with the typical advantages of biofilm technologies, which include consistent treatment, even during upset/load fluctuation conditions, and ease of operation
Return on investment in these products and systems are measured in terms of capital avoidance, suppliers say. By enhancing existing treatment systems, manufacturers can delay the need for a wastewater system expansion.
BioAmp from EcoBionics (www.ecobionics.net), Irving, Texas, is another pretreatment system that uses bacteria to reduce BOD. The BioAmp unit meters up to 31 trillion live bacteria into wastewater every 24 hours, the company says. The bacteria consume the organic carbon sources – primarily sugars – plus fat, oil and grease in the wastewater before the municipal treatment plant measures the BOD of waste for surcharges.
Clean Water Technology Inc. (www.cleanwatertech.com), Los Angeles, offers a number of waste treatment technologies, most focusing on solid/liquid separation processes. One CWT technology is the Moving Bed Biofilm Reactor (MBBR), which consists of thousands of polyethylene biofilm carriers operating in mixed motion within an aerated wastewater treatment process.
When communities of microorganisms grow on surfaces, they are called biofilms or biocarriers. Every biofilm carrier adds to productivity by providing an active surface area, which sustains bacteria within protected cells. This high-density population of bacteria creates the biodegradation within the system.