From zero to 72,000 in three years
Organics diversion success in the Region of Peel
Situated in the heart of southern Ontario’s major urban centres, the Region of Peel is the second largest municipality in the province with a population of more than 1.2 million. Peel consists of three member municipalities (Brampton, Mississauga and Caledon) and provides waste collection and recycling services to 395,000 households and multi-residential units that produce almost 500,000 tonnes of waste per year.
In 2009, using an aggressive 4Rs waste strategy (reduction, reuse, recycling and recovery) Peel diverted 50 percent of waste from landfill. Plus, an additional 20 percent of waste was diverted through Peel’s energy-from-waste facility.
Larry Conrad is Peel’s Manager of Waste Operations, and oversees the region’s compost operations.
“We launched our green bin organics recycling program in the spring of 2007 to 300,000 households,” explained Conrad. “Organics are collected weekly on regularly scheduled waste collection days using split body collection vehicles that collect both blue box and green bin items.” (The program primarily accepts food waste and soiled paper products, but does not accept non-compostable plastic bags, diapers and pet waste.) “We’re collecting more than we have the ability to process at the moment, which is good,” continued Conrad.
In Brampton and Mississauga, green bin organic waste is brought to the Peel Integrated Waste Management Facility (IWMF), and in Caledon it is brought to the Caledon Composting Facility. Both facilities are owned and operated by Peel. The IWMF processes 60,000 tonnes of organic waste per year (30,000 tonnes of green bin waste and 30,000 tonnes of yard waste) while the Caledon Composting Facility processes 12,000 tonnes (6,000 tonnes of green bin waste and 6,000 tonnes of yard waste.)
“On the organics facility tipping floor at our IWMF, trucks off-load approximately 500 metric tonnes of green bin organic waste and yard waste each day,” said Conrad. “The floor is also heated during the winter to keep any moisture-laden material from freezing to it.”
The process begins
As trucks are emptied at Peel’s IWMF, material is inspected for contaminants such as plastic and glass. The green bin organic waste and yard waste are then mixed together using a front-end loader and loaded into a Vecoplan shredder that rips the material into four inch minus pieces. A conveyor then moves the mixed organics from the shredder to one of the facility’s six concrete Christiaens Group composting tunnels. At five metres wide by six metres high, by 30 metres long, each tunnel can hold approximately eight trailers, or 250 tonnes of organic waste.
“Scales mounted on front-end loaders measure the amount of material going into the tunnel, and an overhead conveyor distributes it evenly from side-to-side and end-to-end within each tunnel,” explained Conrad. “Our Christiaens system has worked very well for us.”
When the tunnels are full, air-tight doors are closed and the compost undergoes a five phase process for approximately seven to 10 days. This process is closely monitored by a computerized control system. Phase 1 involves a warm-up to 45 degrees Celsius, and Phase 2 involves active composting at a minimum of 45 degrees Celsius for three days (72 hours.) Phase 3 is a warm up to 55 degrees Celsius and Phase 4 involves pathogen/weed seed kill, at temperatures above 55 degrees Celsius for three days (72 hours.) The final phase involves a cool down for unloading and transport to the Peel Curing Facility.
“During our five-phase process air is pumped through the material by aeration channels in the floor and drawn through the pile by fans in the ceiling,” explained Conrad. “Temperature and oxygen within each tunnel are continuously monitored and water seeping from the material is directed from the facility as sanitary effluent. Gases and odours are removed in a specially designed BioRem biofilter to ensure that the air leaving the facility is as clean – if not cleaner – than the air going in.” (A similar process on a smaller scale occurs at the Caledon Composting Facility utilizing eight Herhof biocells.)
“The next part of the process involves immature compost being loaded into trailers that transport it to our 100-acre curing facility in Caledon,” said Conrad. “The Peel Curing Facility has 24 windrow footprints, each equipped with aeration channels, oxygen/temperature sensors, a ventilator system and a computer monitoring system.”
“The material brought to the facility is unloaded into the windrow footprints and formed into specific dimensions using front-end loaders,” said Conrad. “It takes two days to create one windrow, which measures 50 metres long.”
Getting to the finished product
At Caledon, a Gore cover, which utilizes membrane technology between two layers of polyester, is placed on top of each windrow. “We like the GORE cover,” said Conrad. “The cover provides a protective barrier between the compost and the atmosphere. Once a windrow is formed and covered, oxygen and temperature sensors are placed into the compost through openings in the cover.”
A computer system is used to monitor the sensor outputs (temperature/oxygen readings). If the oxygen content falls outside of the specified range for operation, the ventilator is turned on/off as necessary. The computer then records data at one hour intervals throughout the process. This data is printed and stored onsite after each completed cycle.
“At weeks three, five and seven the Gore covers are removed using a tarping machine and the windrows are turned with an ALLU windrow turner. Our turner is equipped with an irrigation system to pump water into the compost to maintain 55 percent moisture content. After a windrow is turned, the cover is replaced and the sensors are put back in. We like our ALLU turner a lot as well,” said Conrad. “It’s a very durable machine.”
At the end of the curing process, front-end loaders move the unscreened finished compost to a feeding hopper located in the centre of a curing pad. A feeding hopper then feeds the compost onto a conveyor system, which transports the material into the processing building for screening. Here the material is fed onto a three-inch Multistar 2SE Stationary screen supplied by Komptech. Three-inch and over material is fed into a compactor as residue, and the three-inch minus material is fed onto a second screen.
The second screen, also a Komptech unit, is equipped with a pneumatic system to remove plastic contaminants, and separates the compost into two sizes. The half-inch minus is finished compost that can be used for residential, agricultural and commercial markets) and the half-inch to three inch compost is used for other projects such as silt fencing, or carbon amendment in the primary composting facilities.
“The compost is aged for an additional period of time based on the target markets and then laboratory-tested for quality and content,” explains Conrad. “Once it’s tested and approved, the material is sold to markets.” Peel’s compost meets all Ontario Ministry of the Environment and Compost Council of Canada requirements to make it Class A and is CQA (Compost Quality Alliance) certified.
“It’s hard to say where things will be in five years,” said Conrad. “We are just starting to look at how we can increase capacity, and at exactly where we are going to go from here.”
The Region of Peel
5708 Uwharrie Road
25 Kimberly Road, , Suite A
East Brunswick, NJ