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Evaluation of Opportunities for Converting Indigenous UK Wastes to Wastes and Energy
AEA/ED45551/Issue 1
10.2.1 Pyrolysis in the UK
Seamer Carr, Scarborough
The UK’s first full scale waste pyrolysis plant is to be known as Scarborough Power Ltd. Once
operational the plant will consume 18,000 tonnes per annum of high calorific value pre-sorted MSW, i.e. a
form of SRF. 297 After shredding and drying the expected calorific content of this material will be 15MJ/kg.
Simple flash pyrolysis, with technology provided by GEM, will be used to convert the waste to syngas in
the absence of oxygen, which is then ultimately used to generate electricity and heat, expected to be
2.4MW of electricity and 1.8MW of gross heat output.
This project is a joint venture between Yorwaste, pyrolysis technology company GEM, and engineering
consultancy NEL Power, and is part of Defra’s New Technologies Demonstration Programme.
Compact Power, Avonmouth
The Compact Power process is typical of a heated tube system. The schematic (Figure 21) shows the
company’s 8,000 tonnes per annum demonstration plant at Avonmouth. This plant is intended for the
treatment of MSW and clinical waste. Waste may be first sorted to remove recyclables. It is then
conveyed by a screw through a heated tube where it pyrolyses. The pyrolysis gases are then burned in a
cyclone combustion chamber. The residual char falls into a hopper where it is gasified by steam that has
been preheated in the combustion chamber, leaving an ash residue. The gas from the gasification
section is burned with the pyrolysis gas. The hot gas from the combustion chamber is first used to heat
the pyrolysis tubes then to raise steam for power generation. Flue gas clean up is after the boiler and
uses a dry bicarbonate injection system. The residue is reported as a dry, inert gas. The emissions
performance is reported as excellent with most regulated pollutants an order of magnitude below the
statutory limit.
The focus is largely on waste disposal at an acceptable cost on a small scale appropriate to clinical and
industrial wastes, and smaller urban communities. As such it fits well with recycling schemes. Energy
recovery is currently relatively low and comparable with combustion systems. More development would
be necessary to take advantage of the higher efficiencies offered by gas turbine and reciprocating engine
cycles.
Figure 21 Schematic of Compact Power’s demonstration plant at Avonmouth
297 Defra Factsheet, Scarborough Power, http://www.defra.gov.uk/environment/waste/wip/newtech/dem-programme/pdf/Scarborough-Power.pdf