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Liquid Composting and Reduced Waste Disposal Costs
Fujitsu Technology and Business of America reduced labor and carting costs associated with food waste disposal at its corporate cafeteria by installing a biodigester that converts food solids into drain-safe wastewater in 24 hours.
Manufactured by Power Knot LLC of San Jose, CA, the cafeteria’s LFC-70 biodigester uses a mix of natural microbes and enzymes, along with infusions of hot and cold water and oxygen, to aerobically convert biodegradable food waste into grey water that drains into municipal waste lines.
The facility serves breakfast and lunch to approximately 150 employees, generating about 110 lb (50 kg) of food waste per day. Robert Curtis, environmental, health, safety, and security services specialist, says the biodigester can process up to 280 lb (125 kg) of waste every 24 hours.
Employees separate packaging from the food, and load waste through a hinged lid on top of the stainless steel enclosure.
“The machine doesn’t cycle, so we can keep adding waste,” Curtis says. “Some employees wanted to accumulate food scraps, but it’s better to keep adding waste as it’s generated.” Curtis says the process is relatively odor free. “It smells faintly like cantaloupes.” As a result, the unit does not attract pests and can be installed in the kitchen rather than in a special area. In addition to reducing disposal costs, diverting roughly 14 tons (13 tonnes) of food waste from landfills reduces CO 2 emissions by about 51 tons (46 tonnes) per year.
Information on drum temperature, door openings, water volume, water temperature, CO 2 emissions avoided, service reminders, and weight of the food waste digested by hour, day, week, month and year can be accessed on the unit’s touch screen or a smart device, laptop or computer via the cloud.