MSW as a feedstock for biofuels production
It is estimated that a potential 44 million tonnes of Municipal Solid Waste MSW could be available in the EU in 2030 (See Wasted - Europe's Untapped Resource: An assessment of advanced biofuesl from wastes and residues). Municipal Solid Waste.
The latest EurObserv'ER Renewable Municipal Waste Barometer estimated that the production of primary renewable energy recovered by household refuse incineration plants in the EU increased by just 0.7% in 2013 to achieve 8.7 million toe. However, heat sales to networks surged, reflecting better use of the primary energy.
MSW can also be converted into liquid and gaseous biofuels for production of heat and power or be used as a transport fuel. Typically, management of domestic wastes involves separation at source into:
- Recylable materials (metals, paper and plastics) - used for manufacture of recycled products
- Organic fraction (putrescible food waste) - may be converted to biogas via anaerobic digestion
- Solid Recovered Fuel SRF (the fraction of MSW that cannot be recycled e.g. shredded textiles, wood, paper, card and plastics) - SRF can be combusted or converted to syngas, and then be use for bioenergy or be processed into advanced biofuels.
An advantage of using MSW is that the feedstock is often supplied for free by Waste Managament companies (as an alternative to landfill, with the economics in many cases driven by landfill taxation). This balances the relatively high capital expenditure required for an integrated gasification system and fuels synthesis facility (for example, based on Fischer Trospch or catalytic conversion) to convert syngas to diesel, jet fuel, or methanol/ethanol.
For example, a 160 MW thermal waste gasifier in Lahti, Finland, uses SRF that would otherwise be destined for landfill. The gas is cooled and cleaned before being passed to the boiler.
On 6 January 2016, British Airways announced that it has been forced to shelve its GreenSky project to create 16m gallons of jet fuel from waste every year, partly due to a lack of government support [Source: The Guardian, UK]. British Airways planned to use 600,000 tonnes of MSW (collected in London) to produce over 50000 tonnes of biojet fuel and 50000 tonnes of biodiesel annually. The GreenSky project was to have used Solena's Plasma Gasification (SPG) technology, which can process 20-50% more waste than conventional gasification technologies, and Velocys technology for production of the jet fuel.
In June 2013, Abengoa Bioenergy inaugurated its W2B Demonstration Plant for conversion of MSW to cellulosic ethanol. The plant has a capacity to treat 25,000 tons of municipal solid waste (MSW) to produce 1.5 million litres of bioethanol for use as fuel. The demonstration plant located in Babilafuente (Salamanca, Spain) uses W2B technology developed by Abengoa to produce second-generation biofuels from MSW using a fermentation and enzymatic hydrolysis treatment. During the transformation process, the organic matter is treated in various ways to produce organic fiber that is rich in cellulose and hemicellulose, which is subsequently converted into bioethanol. As Abengoa has filed for bankruptcy, the plant is currently idle.
In September 2014, Fulcrum Bioenergy Inc announced a $105m 'Biorefinery Assistance Program' loan guarantee from the USDA, which will support development of the proposed 10 MMgy Sierra BioFuels facility to convert MSW into syngas, followed by a Fischer Tropsch step to create second generation biodiesel and bio jet fuel. The Sierra BioFuels Plant will include a Feestock Processing Facility and a Biorefinery that will convert approximately 147,000 tons of prepared MSW feedstock into more than 10 million gallons of SPK jet fuel or diesel annually. Fulcrum has enteed into a long-term, zero-cost MSW feedstock agreements with Waste Management and Waste Connections, two of the largest waste service companies in North America, and a fuel off-take agreement with Tenaska BioFuels. The Sierra BioFuels Plant is expected to be one of the United States’ first fully operational, commercial-scale MSW-to-renewable fuels production plants. In May 2015, Fulcrum awarded an engineering, procurement and construction contract to Abengoa for the construction of the Sierra Biorefinery. The $200 million fixed-price contract guarantees the schedule, cost and performance of the Sierra Biorefinery. However, as Abengoa has filed for bankruptcy, the future of Fulcrum's Sierra BioFuels plant is unclear.
In June 2014, Enerkem inaugurated its commercial MSW-to-ethanol facility in Edmonton, Canada. Enerkem, through its affiliate Enerkem Alberta Biofuels, signed a 25-year agreement with the City of Edmonton to build and operate the plant that will produce and sell next-generation biofuels from non-recyclable and non-compostable municipal solid waste (MSW). Sorted MSW is shredded and then fed into a gasifier, where heat and pressure create syngas, which is then cleaned and conditioned prior to catalytic conversion to methanol and ethanol. With a production capacity of 38 million litres per year (10 million gallons per year), the Enerkem Alberta Biofuels facility is the world's first major collaboration of its kind between a metropolitan centre and a waste-to-biofuels producer. Future plans of Enerkem include building a commercial facility through VANERCO, a joint venture formed by Enerkem and GreenField Specialty Alcohols. The VANERCO commercial facility will be one of the first integrations between an existing, first generation ethanol plant and a new cellulosic ethanol plant. VANERCO will use Enerkem’s exclusive technology to produce cellulosic ethanol from non-recyclable waste from institutional, commercial and industrial sectors as well as construction and demolition debris. The VANERCO facility will be located on the site of GreenField’s current first-generation ethanol facility. Site preparation has started. Construction should begin in 2016 (see Enerkem's presentation at SPM7 for more details).
In July 2014, Fiberight announced that Andritz was to supply equipment, engineering, and field services for Fiberight’s cellulosic ethanol plant in Blairstown, Iowa. Andritz technology will be used for continuous pre-treatment of municipal solid waste feedstock which will then be converted into cellulosic ethanol using Fiberight’s existing fermentation and distillation processes.