Automated Composting Makes Quick Work Of Food Waste

In California, Fujitsu disposes of its food waste with a system that meets compliance while easing the task for its facility management team.

Many organizations face challenges in meeting local laws that regulate how they dispose of food waste. Chief among these is the cost of compliance, which includes assigning personnel to sort waste before disposal, maintaining separate areas for waste storage, paying companies to properly dispose of waste, and sometimes setting up and staffing composting operations of their own.

One company reduced the time and expense of handling and disposing of food waste with a compact machine that simplifies disposal and eliminated much of the cost associated with the process. Fujitsu Technology and Business of America Inc. of Sunnyvale, CA, achieved these benefits with an LFC® biodigester developed and manufactured by Power Knot LLC of San Jose, CA.

food waste
At its facility, Fujitsu Technology and Business of America uses a biodigester machine to process its food waste. The LFC biodigester developed by Power Knot is seen here in the foreground.

The composter, installed in the kitchen of Fujitsu’s corporate cafeteria, reduces the steady stream of organic food waste that is generated by food preparation and consumption during the day into “graywater.”

The LFC unit operates in the food preparation area, serving some 150 employees for breakfast and lunch in the cafeteria daily. Robert Curtis, environmental, health, safety, and security services specialist, says, “The cafeteria generates 50 pounds of food waste daily,” which is composted in the LFC-70. One of Power Knot’s smaller models, it can process up to 280 pounds of waste every 24 hours.

Curtis says a local regulation for restaurants to compost food waste went into effect in 2015, but Fujitsu was in compliance as it had taken delivery of the LFC-70 in 2011. Prior to acquiring the unit, the company was paying contractors to haul its food waste to a landfill. The food waste piled up costs for loading, storage, and transportation. The trucks that carried the waste to the landfill additionally generated carbon dioxide emissions that increased the company’s carbon footprint. Now the small amount of waste that cannot be bio-digested in the LFC, such as bones and fibrous material, is disposed of three times a week along with other trash.

The LFC biodigester uses a mix of natural microbes and enzymes, along with infusions of hot and cold water and oxygen, to aerobically decompose biodegradable food waste. The continuous cycle takes 24 hours, during which the biomaterials break waste down into “gray” or organic water safe for draining into ordinary municipal waste lines. Curtis has noted that the nutrient rich water would make a good lawn fertilizer if he had a way to recapture it.

The machine operation is simple, says Curtis. Employees separate contaminants like packaging from the food, as well as scraps that cannot be bio-digested, and load waste through a secure door on top of the cabinet. And, since its process is continuous the machine can run 24/7 even without adding food waste to process. “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.”

The machine runs silently and Curtis says is relatively odor free. “It smells faintly like cantaloupes (whose rinds take longer to digest),” he allows. As a result, the LFC unit does not attract pests and can be installed where it is most useful, in the kitchen, rather than in a special area.

And the company has found little penalty in energy use, and cost of operation is low. “The savings from turning the machine off are so minimal that we keep it running continuously, even over Thanksgiving and the December shutdown,” Curtis says. This helped Fujitsu achieve a return on investment in 18 months through significantly reduced garbage hauling to a landfill.