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Gas supplier Air Products is to build an energy from waste plant which will use plasma gasification technology for the first time in the UK.
The company has submitted an environmental scoping document to Stockton-on-Tees Borough Council for a 49MW renewable energy plant at Billingham, Cleveland, which will incinerate landfill waste to produce electricity.
The proposed plant will use plasma gasification technology by Canadian firm AlterNRG, and may also be used to demonstrate the viability of producing hydrogen to use in fuel cells.
Air Products is best known for supplying gases to the chemicals and manufacturing industries.
Ian Williamson, European hydrogen and bio energy director at Air Products, said: “We did energy from waste projects in the US during the 1980s, but everyone was strongly against incineration, so they were stopped.
“This is going back to that, but this time there is a much stronger renewable and environmental aspect to the projects.
“Over 90% of the waste arriving at the site will be diverted from landfill and used as a renewable energy source.”
Plasma gasification
AlterNRG’s process uses a Westinghouse Plasma Gasification System (below), which exposes feedstocks such as municipal solid waste, industrial waste or biomass to temperatures over 5,000°C in the presence of controlled amounts of steam, air and oxygen.
The feedstock reacts in the gasifier with the steam, air and oxygen to produce a synthesis gas (syngas) and slag. Syngas, composed primarily of carbon monoxide and hydrogen, can be used for industrial purposes as a substitute for natural gas.
The system uses plasma torch technology, where a plasma stream is created by the interaction between air and an electric arc created between two electrodes. The interaction of the gas with the electric arc dissociates the gas into electrons and ions enabling the gas to become electrically and thermally conductive.
Feedstock materials enter the gasifier through a feed port which can be located on the side of the reactor or at the top. The feedstock either gasifies immediately upon entering the reactor or falls on to the coke bed where complete gasification occurs.
Non-gaseous, inorganic components in the gasified feedstock, such as the rocks, dirt and other impurities, separate and leave the bottom of the gasifier as a glass-like slag. Slag, which is environmentally benign, can be sold for use an aggregate to the construction industry.