Transforming Waste Management: The Disco Road Anaerobic Digestion Project
Building upon the proven success of the Dufferin Organics Processing Facility (DOPF), CCI Bioenergy Inc. (CCI), in collaboration with strategic partners AECOM Canada and Veolia Canada, embarked on another groundbreaking endeavor with the City of Toronto – the Disco Road Anaerobic Digestion Project. This visionary partnership led to the design and construction of a second AD plant, owned by the City, with a capacity to process 75,000 metric tonnes of Source Separated Organics (SSO) collected through the Green Bin Program. Commencing its waste processing in December 2013, the facility reached full capacity by March 2014, and today, CCI continues to provide daily operations, management, and technical support.
Currently, the City of Toronto collects over 130,000 metric tonnes of residential and commercial SSO annually, emphasizing the pressing need for sustainable and efficient waste processing solutions.
The chosen location for the facility was the Disco Road transfer station – an urban site and one of seven integral components of the City’s solid waste infrastructure. The facility’s construction involved a significant undertaking, as it was physically built on an old landfill site. Over 95,000 metric tonnes of material were excavated and safely disposed of, requiring more than 3,300 truck trips. The solid base necessary for the foundation, building, tanks, and equipment loading was established using over 900 steel pilings filled with rebar and concrete.
The facility employs a state-of-the-art BTA® Hydromechanical Pre-treatment system to handle the waste feedstock, characterized by a high plastic content due to the collection in plastic bags. With three waste pulpers and three grit removal systems, inert contaminants and non-digestible elements are efficiently removed from the SSO. A telescopic loader fills a hopper, conveying the SSO to the pulpers with a load volume of approximately 15 metric tonnes.
The anaerobic digestion process operates within the mesophilic range, utilizing two 5,300 m3 digesters with full mixing using compressed biogas. This biogas powers the dual-fuel boilers, generating the necessary heat for digestion. Notably, a gas upgrader system is employed to convert biogas to Renewable Natural Gas (RNG), attaining pipeline quality.
Post-digestion, the resulting digestate undergoes dewatering using two centrifuges, with a third standby unit available when required. The digester solids are then transported for aerobic finishing at an off-site compost facility, situated about 100 kilometers from the plant. The virtually non-existent inert contamination ensures that the final high-quality compost is Class AA, distributed to higher-value markets. All liquids within the waste are reclaimed and reused as process water in the closed-loop system. Any excess liquids are treated on-site through a biological effluent treatment system before discharge to the local sanitary sewer.
Innovative Delivery Team:
The facility’s design, construction, and guaranteed performance are the outcome of a cohesive partnership involving CCI and its trusted partners – AECOM Canada, ES Fox Construction, and BTA International. CCI plays a key role in the daily operations, with Veolia Water Canada leading the operating team. CCI’s contributions encompass a wide array of services and equipment, including process design, engineering support, waste receiving designs, procurement, and installation of the BTA® Waste Pulpers / Grit Removal System (GRS) / Process Control System, solids/liquids separation system, and digester engineering.
The Disco Road Anaerobic Digestion Project not only advances Toronto’s waste diversion goals but also aligns with the City’s commitment to sustainable practices. The facility’s capacity meets the demands of the ever-successful Green Bin Program and produces valuable community-based bioenergy for local consumption. Generating high-quality Class AA compost and operating without odors or off-site nuisances, the facility complies with the Toronto Green Standard while fostering local economic growth through job creation, goods, services purchases, and tax contributions.
June 23, 2023