Scott

August 17, 2010 | General

Yard Trimmings, Food Waste Composting In Vancouver Region


BioCycle August 2010, Vol. 51, No. 8, p. 43
Metro Vancouver’s contract with a local composting facility enables municipalities to take advantage of a discounted tipping fee for up to 50,000 metric tons of source separated organics.
Molly Farrell Tucker

SINGLE-family households in a number of cities in the Metro Vancouver region of British Columbia are now putting out food scraps with their yard trimmings for curbside collection. Food waste diversion is part of Metro Vancouver’s Zero Waste Challenge, with a goal to reduce, reuse or recycle 70 percent of all municipal solid waste by 2015. Metro Vancouver is comprised of 22 municipalities, one electoral area, and one treaty First Nation, each of which has its own programs and waste planners. One of the core services Metro Vancouver provides to these municipalities is solid waste management. Metro Vancouver conducted a waste composition study in 2007 and found that there are about 551,000 tons of source separated organics (food scraps, yard trimmings and soiled paper) in the municipal solid waste stream. The study estimated that between 276,000 and 386,000 tons are readily collectable.
“Almost all municipalities in the region have been collecting yard trimmings from single family homes for over a decade,” says Ken Carrusca, Division Manager of the Integrated Planning Division of Metro Vancouver. “There has been limited commercial food scraps composting in the region before. The private sector had difficulty overcoming the challenges of siting and building a facility that was commercially viable and had good odor control. With limited facilities to bring the food scraps for composting, most municipalities were not able to offer this service to their residents.”
Metro Vancouver put out a call for expressions of interest in July 2008 for companies interested in establishing a permanent regional facility to process 50,000 metric tons (55,000 tons/year) of organic wastes. There were 23 respondents. Metro Vancouver hired Camp Dresser & McKee, Inc. in Boston, which recommended asking 10 of the respondents to submit proposals of economics. Fraser Richmond Soil & Fibre was selected in December 2008. The facility is located in Richmond, British Columbia, south of the City of Vancouver.
Metro Vancouver negotiated a tip fee agreement with Fraser Richmond and the two parties signed a contract in June 2009. Fraser Richmond became a wholly owned subsidiary of Harvest Power Canada Ltd. in October 2009. Harvest Power, a developer of energy and composting facilities for organics recycling, is headquartered in Waltham, Massachusetts and has 55 employees, 30 of whom work at the Fraser Richmond facility.

ROLLING OUT COLLECTION
Two municipalities in Metro Vancouver, Port Coquitlam and Port Moody, already had been cocollecting food scraps with yard trimmings. Four other municipalities – Delta, Coquitlam, West Vancouver and Langley Township – agreed to participate in a pilot to further test food waste collection logistics. The program ran from October 2009 to March 2010 and included approximately 2,800 single-family households. Residents put their food scraps in their yard trimmings containers, which were either wet-strength kraft bags or reusable plastic cans. “Cocollection of food and yard wastes together did not cause any significant problems with odors or pests, and avoided the infrastructure associated with separate collection,” says Carrusca.
Over 375 tons of food scraps and yard trimmings were collected during the six-month pilot, and composted with clean wood waste at Fraser Richmond. Carrusca notes that participation rates and an actual increase in diversion during the pilot program were lower than expected. “It is likely that it would take more effort, education and time than the six-month pilot allowed to achieve the diversion levels seen in other locations,” he says. “Providing organics collection on a more frequent basis improves the organic waste diversion. Research on results in other locations has found that biweekly garbage collection with weekly organics collection made a substantial difference.”
Results from the pilot, including feedback from residents, were used by Metro Vancouver to create a regional collection program for municipalities that wanted to participate in cocollection of food waste and yard trimmings. Five municipalities joined in on the organics processing agreement including the cities of Burnaby (pop. 218,000), Port Coquitlam (pop. 55,000), Port Moody (pop. 31,000), Richmond (pop. 190,000) and Vancouver (pop. 615,000).
“Other municipalities have until the end of December 2010 to join the Metro Vancouver organics recycling program if they want to lock in the low tip fee,” says Jan Allen, lead engineer and technologist for Harvest Power. “There is a limited amount of capacity offered through the Metro Vancouver agreement of 50,000 metric tons/year [55,116 tons/year]. If another three or four municipalities join, we will have reached the limit, but municipalities can still contract directly after that with Harvest Power.”
The city of Vancouver began phase one of its Residential Food Scraps Collection Program on April 22, 2010 by signing on with Metro Vancouver’s contract with Fraser Richmond Soil & Fibre. Fruit and vegetable scraps, coffee grounds and filters, teabags, eggshells and garden waste are collected every other week. “In Vancouver, yard trimmings are collected curbside in carts from single family residential properties biweekly,” says Bob McLennan of the Solid Waste Management Branch for the City of Vancouver. “Because collection remains biweekly, the types of food scraps are limited to avoid excess odors and potential attraction of flies and rodents.”
Garbage in the city is collected curbside in carts from single family residential properties weekly. “The City of Vancouver is planning to convert to biweekly garbage collection and weekly compostables (food scraps and yard trimmings combined) collection in 2011,” says McLennan. “The range of food scraps accepted will be expanded at that time to include all fruits and vegetables, meat, fish, dairy, bread, cereal products and food-soiled paper.”
Trucks used to collect the organics are typically owned and operated by the municipalities. As in the pilot, single-family residences commingle food scraps with yard trimmings in wet-strength kraft bags or reusable plastic cans.
The Metro Vancouver region has a single-family population of 1.4 million and a multifamily population of 900,000. Food waste collection from multifamily and commercial buildings is slated to increase significantly in June 2011. “That is when our high solids anaerobic digester system will be commissioned and operating,” says Paul Sellew, founder and CEO of Harvest Power. “The percentage of food waste collected has been relatively modest so far, but we expect a large increase when we expand into multifamily and commercial buildings.” Adds Carrusca, “The goal is to divert an additional 280,000 metric tons [309,000 tons] of organics per year by 2015 from all residential and commercial sectors.”

ORGANICS PROCESSING
Food waste and yard trimmings diverted from the Metro Vancouver programs are composted in aerated static piles at the Fraser Richmond facility. Piles are covered with bark, compost and wood ash, which act as a natural biofilter to treat odors. Negative aeration also captures exhaust from the covered piles, which is treated through biofiltration.
The high solids anaerobic digester system scheduled for construction at Fraser Richmond will occupy one acre of the 30-acre site. The new system is permitted to process up to 30,000 metric tons annually (33,000 tons/year) of organic materials. “We have our permits and are waiting for some final regulatory approvals, and plan to start construction before the end of 2010,” says Sellew. Harvest Power anticipates hiring 50 people for the construction process and an additional 15 permanent employees to manage, operate and maintain the facility.
The high solids anaerobic digester (HSAD) is designed to process organics with 25 to 50 percent solids, compared to wet anaerobic digestion systems, which process organics with 2 to 15 percent solids. “Food scraps and yard debris are stackable substrates that can be processed more efficiently in Harvest’s digesters,” says Allen. “The HSAD process requires very little water and energy and has no moving parts, reducing operating costs.” Biogas will be used as fuel to produce electricity, cleaned to biomethane (pipeline natural gas) or processed into compressed natural gas.
Residents in the participating municipalities are currently not allowed to use plastic bags, including compostable or biodegradable bags to line their compost pails or cans. “The pricing we gave Metro Vancouver is so attractive that we need to keep contamination at a very low level,” says Sellew. He adds that Harvest Power is considering allowing the multifamily programs, when they are brought on line, to use compostable bags that meet the ASTM D6400 standards.
Allen is working with waste haulers that provide service to multifamily and commercial buildings in a number of communities. “We will begin the program a few months before the anaerobic digester facility opens, so that haulers will have the opportunity to educate their customers and learn how to control contamination,” he says. “This material will be composted separately while the digester is completed.”
Harvest Power plans include building more facilities in the Vancouver area to process additional organics. “Our Richmond facility can take in 33,000 tons and we hope to build more infrastructure to expand our capacity in the region,” says Allen.

Sidebar p. 44
DIRECTORS VOTE TO MOVE AHEAD ON MSW INCINERATOR
ON July 30, the Metro Vancouver Board of Directors approved an integrated solid waste plan that includes construction of a $470-million incinerator in the region to handle around 550,000 tons/year of MSW. The plan also supports programs such as residential organics diversion as described in the accompanying article, but given expected increases in waste generation in the region, additional disposal capacity is needed. After evaluating options, they decided on incineration. “The decision to adopt Waste-to-Energy as the preferred disposal option was more controversial, but in the end, the science was clear – from an economic, environmental and social perspective, additional Waste-to-Energy capacity is the best choice,” said Board Chair Lois Jackson.
Metro Vancouver’s solid waste management plan must now be approved by Barry Penner, British Columbia’s Environment Minister. There is significant public opposition to the plan. Nora Goldstein


Sign up