Off the Plate

Lynn Merrill

Each year in the United States, more than 21.9 million tons of food waste make a sloshy trip to the landfill.

Yet, the potential for food waste diversion is great. Traditional recycling programs may get municipalities tantalizingly close to meeting diversion mandates of 50 percent or more, but they don't offer the waste diversion opportunities available through commercial food waste collection.

With commercial collection, concentrated quantities of food waste are generated in pre-consumer, industrial settings such as canning or food preparation operations. Grocery stores, institutional cafeterias and restaurants further offer copious quantities of over-ripe and semi-eaten post-consumer wastes that can be composted or used as animal feed.

Starting Off Small

While it can be challenging to establish economically viable separation programs, several haulers are working within their communities to make it work. Nick Boersema, divisional territory manager for In-Plant Services of Canadian Waste, Strathroy, Ontario, Canada, says his company began a food waste collection pilot because it is seen as a “green earth issue,” plus “the municipality is committed to it.”

Currently, the diversion project is in the planning stages and involves only one large manufacturing company's cafeteria. “You've got a small group of workers, so it's a little bit easier to control quality,” Boersema says. But if all goes well, other customers are ready to start similar programs. “There's a demand for [it],” he says.

Yet collecting food waste from even one facility presents difficulties. “The composter that I am using doesn't have the ability to do the richer organics, so things like cooking oils, mayonnaise and butter … do cause them some grief,” Boersema says. “We have to be careful as to what goes into it.”

To alleviate any confusion, Canadian Waste will provide education and signs on containers, targeting the food preparation area first. With a smaller pool of workers, it will be easier to control quality, Boersema says.

“As we move into the cafeteria, it will definitely be more challenging. It will be an ongoing, coaching affair, like we have in a lot of our recycling programs.”

While separation is more cost-intensive for the hauler, the manufacturing company is motivated by the diversion opportunities and subsequent reduced disposal costs.

Meantime, Boersema is working on including other materials to increase the diversion volume. He is considering “wet paper towels, things that would normally pose recycling problems,” he says.

Portland's Pair of Pilots

When Portland, Ore., decided to divert food waste, it addressed higher collection costs by soliciting proposals in 2000.

“We knew there would be costs in collecting food wastes because it requires sending a separate truck and person on a scheduled collection route that was not compact,” says Judy Crockett, commercial program specialist with the city's Office of Sustainable Development. “We felt the haulers would be unwilling to incur the additional costs unless we underwrote some of them, so we did.”

Portland eventually initiated two pilots starting in 2000 — one with Houston-based Waste Management Inc., the city's largest commercial hauler providing collection, and the second comprised of several smaller haulers. From there, haulers helped the city to identify the commercial “food producers,” who were asked to join the pilot. Eventually more than three dozen businesses participated, including coffee shops, grocery stores and a food wholesaler.

“We were trying to get a fairly broad range, both in size and type, of businesses involved in the pilot so that we could determine which businesses were going to be the right size to be covered with the mandatory ordinance,” Crockett says.

In the pilots, which concluded in October 2001, Portland used one- and two-yard front-loading plastic bins, plus 60-gallon carts. All food waste — including meat, food-soiled paper and waxy corrugated cardboard — was collected and sent to a composting operation outside the Metro area. Grease was the only material that was not accepted.

This made consumer education challenging. The city used college students to help run the system and to help educate customers at their sites.

“Portland State University students provided a lot of the follow-up and day-to-day management,” Crockett says. Educational materials were translated into English, Spanish and Chinese because those are the three most common languages spoken by Portland restaurant employees.

Nevertheless, more obstacles surfaced, for example, using plastic bags to contain food wastes, Crockett says. “We purchased compostable plastic bags for the first pilot,” she says. “We didn't make that available in the second pilot, mainly because it was expensive. In addition, when people run out of the compostable bags, they use whatever bag that happens to be around.”

Canadian Waste's Boersema agrees that bags add to the costs of food waste diversion. “When you have a client that used to pay pennies per bag and suddenly they're looking in excess of a dollar [for a biodegradable] bag, that adds costs to an otherwise effective program,” he says.

Portland has managed its program without a local food waste processor. “There are no facilities in the Portland area that are permitted to take plate scrapings and food wastes containing meat,” Crockett explains. So to ensure the long-term success of the diversion program, the city has to find a local processor to avoid transporting heavy wastes long distances.

“Portland is anticipating having commercial food waste collection processing on-line by the end of next year,” she says, which should reduce program costs.

An Educator's Education

Although food waste collection has been a part of campus life since 1993, Illinois State University, Normal, Ill., faces another kind of educational issue: high turnover among the cafeteria staff and residents. Additionally, because the waste is used for animal feed in addition to sometimes being composted, it must meet strict FDA regulations.

In the beginning, “we wanted to look at what we could do to recycle food wastes,” says Paul Walker, professor of animal sciences. “If you take a loaf of bread, a head of cabbage or a chuck of round and try to compost it, it decomposes pretty slowly because of the high nitrogen content and density. If you grind that material up, it increases surface area [and] makes a homogenous product that composts fast.”

To experiment, the university decided to put the food waste in pulpers, Walker says. Using a $180,000 grant from the Illinois Department of Commerce and Community Affairs, four dining centers were renovated to install the pulpers and establish a utilization project.

To sterilize food waste for animal feed, the university also had to install equipment to treat the food to kill pathogens and to prevent the spread of mad cow disease, Walker adds.

Now, students bus their own trays in the cafeterias, removing glass-ware, plates and silverware. Remaining materials are sent to the dining center, where the staff pulls off plastics, missed glasses and silverware. Food waste then is scraped into a recycled water trough that transports the material to the pulper.

An extruder process forces pulped material through a machine which, through the force of friction, raises the temperature of the material to 300 degrees and sanitizes the waste for animal feed.

The pulped material is loaded into 30-gallon tubs that are transported daily by truck to the feed center where the food material is used as feed or sent to the university's compost facility.

Currently, “the only time we [use it as] feed is if we're doing a research trial — normally our food waste is composted,” Walker says. But when the school initially started the program in 1993, the pulped waste was fed to cows.

“We did that for three years, replacing 50 percent of [the cows'] energy and all their supplemental protein,” Walker says.

Indeed, cafeterias are a high source of food waste. “Initially, students paid one fee for meals, picked all they wanted to eat, then ate it or threw it away,” Walker recalls. Approximately 1 ton per day was produced, then pulped.

Later, two cafeterias were converted into pay-as-you-go, and national fast food vendors were added to the program. “If students are paying for every item, they only take what they're going to eat,” Walker explains. “We immediately noticed food waste went down.”

Instead of 1 ton per day, the university reduced its volume to 1,300 pounds per day, Walker says. However, switching to food vendors that use more non-compostable Styrofoam and plastic increased the waste stream. “We are trying to address that,” Walker adds.

Regardless, the cafeterias still produce a considerable amount of waste food, which is mixed with landscape and livestock waste, then composted. The facility produces about 40,000 tons of compost per year, which is given away to residents. Landscapers and greenhouses are charged a $10 per ton loading fee.

Clearly, food waste collection and diversion can be challenging. Project managers must find processing facilities that can take both meat and vegetable waste along with mixed papers and other materials. Haulers also have to develop a dense enough collection route to make the program cost-effective. Educating consumers and staff about separation also may demand more intensive efforts than traditional recycling programs.

Nevertheless, despite their difficulties, Canadian Waste, Portland and Illinois State University are preparing the ground to grow a successful food waste diversion program.

Lynn Merrill is the director of public services for the city of San Bernardino, Calif. Visit www.wasteage.com.

FRONT BURNER ISSUES

Admittedly, food waste is heavy, has a high water content and quickly produces large volumes of odors as it begins to decompose. The waste attracts vectors and usually must meet tight public health codes regulating storage, collection frequency and disposal practices. The contents also are highly acidic, which can damage metal collection containers and refuse trucks.

To further complicate matters, end-markets are skittish about the quality of the material. Broken glass or rusting metals in a cart of vegetable waste destined for animal feed, for example, can render a load unusable. But separating contaminants before or after processing can be difficult.

Adding source-separated food waste to existing composting or animal feed operations also can trigger additional regulatory requirements, which creates an entirely different set of concerns.

For example, California requires composting operations that accept food waste to obtain a solid waste facilities permit, while a composting operation that just accepts green waste may only require a registration permit, depending on the material type and volume.

There is additional concern that food waste mixed with animal feedstock could spread transmittable diseases. So the Food and Drug Administration (FDA), Washington, D.C., along with state and local agricultural governing bodies, have added laws to ensure that feedstock is sanitary.

Despite these challenges, however, some communities persist in their food waste diversion efforts, noting its value.
— Lynn Merrill