Edmonton Waste-to-Biofuels Facility, Canada
Key Data
On 31 August 2010, Enerkem Inc. started construction of a commercial scale waste-to-biofuels plant in Edmonton, Alberta in Canada. The plant will convert municipal solid wastes (MSW) into biofuels. It will have the capacity to produce 36 million litres (10 million gallons) of methanol and ethanol a year.
The facility is expected to start up in 2012.
The estimated cost of the project is C$80m. It is expected to create about 180 direct and indirect jobs during its construction, design and operations.
Enerkem operates a pilot waste-to-biofuels plant in Sherbrooke, Quebec (since 2003) and a commercial-scale demonstration plant in Westbury, Quebec (since 2009).
Besides the Edmonton plant, Enerkem is developing another 36 million litres a year waste-to-ethanol plant in Mississippi, US (starting operations in 2013).
Owners and financing of the biofuels plant
The Edmonton project is part of a C$131m integrated project that includes an C$11m advanced energy research facility and the city's C$40m Integrated Processing and Transfer Facility (IPTF).
Enerkem Alberta Biofuels (EAB), a wholly owned subsidiary of Enerkem, is constructing the plant in partnership with the city of Edmonton and the Government of Alberta through Alberta Innovates – Energy and Environment Solutions. EAB will own and o perate the facility.
The total project received funding of C$32.35m from the government and the city of Edmonton.
Plant design
The biofuels plant will be based on a standardised packaged system. The modules will be manufactured and assembled off-site, and transported to the site for installation.
Feedstock
The city of Edmonton will annually supply 100,000 dry metric tons of sorted and dry municipal solid waste to the plant under a 25-year agreement with Enerkem. The non-compostable and non-recyclable solid wastes will come from household and will be sorted in the IPTF.
The IPTF will perform three main functions – waste transfer, pre-processing and conversion of the MSW to refuse derived fuel (RDF).
In the pre-processing, the wastes will be sorted into three streams by manual and mechanical means. The organic materials will be transferred to the Edmonton composting facility, the metals and cardboard materials for recycling, and the non-compostable and non-recyclable wastes to the RDF plant. A mechanical system in the RDF plant will prepare and shred the solid wastes for use as feedstock for the biofuels plant.
Conversion technologies
The Edmonton biofuels plant will use Enerkem's proprietary thermo-chemical process for the conversion of carbon-rich wastes into synthetic gas (syngas) and then methanol and ethanol. Research and testing on the in-house developed technology was started in 2000 and the technology was pilot tested for over 4,000 hours.
The Edmonton advanced energy research facility was established by the city of Edmonton to develop and demonstrate green chemicals and biofuels conversion technologies using the wastes. The research facility will conduct research on different wastes for their conversion into dimethyl ether, synthetic diesel, synthetic gasoline and chemical products.
Enerkem's waste-to-biofuels plant will increase the diversion rate of Edmonton's municipal wastes from 60% to 90%. It will thereby reduce the greenhouse (methane) gas emissions produced during the landfill decomposition. The green transportation fuel will partially replace the petroleum fuels.
The plant is expected to decrease the carbon dioxide (CO2) footprint in Alberta by about six million tons over the next 25 years of its operation. When used as a 5% ethanol blend, the biofuels will be sufficient for about 400,000 cars a year.
Process technology
The process adopted at the plant involves four steps:
- pre-treatment of the feedstock
- gasification
- cleaning and conditioning of the syngas and
- conversion into liquid fuels.
The shredded MSW is stored in a container that is connected to a bubbling fluidised bed gasifier by a front-end feeding system. The gasification at proper temperature and pressure (low severity parameters) breaks the chemical bonds. Conversion of the feedstock into uniform syngas is expected to take less than 10 seconds.
Gas scrubbing and conditioning of syngas take place in a sequential conditioning system. The syngas then undergoes a sequential catalytic conversion process. The catalysts rearrange the gas molecules to produce methanol and ethanol. The process is environmentally friendly as it consumes less energy than it produces and requires minimal water supply in a closed-loop system.
Contractors
The construction management contract for the research facility building was awarded to Dominion Construction. Enerkem designed, procured, installed and will commission the equipment and is also responsible for the overall integration of the pilot and laboratory processes.
