Pyrolysis is NOT a combustion process and can be defined as the thermal decomposition of organic material through the application of heat in the absence of oxygen.
"The Thermal decomposition of organic material through the application of heat in the absence of oxygen." (The Recyclers Lexicon: A Glossary of Contemporary Terms and Acronyms, Resource Recycling Inc., 1995).
The Pyrolysis process is an advanced conversion technology that has the ability to produce a clean, high calorific value gas from a wide variety of waste and biomass streams. The hydrocarbon content of the waste is converted into a gas, which is suitable for utilisation in either gas engines, with associated electricity generation, or in boiler applications without the need for flue gas treatment.
This process is capable of treating many different solid hydrocarbon based wastes whilst producing a clean fuel gas with a high calorific value. This gas will typically have a calorific value of 22-30 MJ/m3 depending on the waste material being processed.
The lower calorific value is associated with biomass waste, the higher calorific value being associated with other wastes such as sewage sludge. Gases can be produced with higher calorific values when the waste contains significant quantities of synthetic materials such as rubber and plastics.
Solid char is also produced from the process, which contains both carbon and the mineral content of the original feed material. The char can either be further processed onsite to release the energy content of the carbon, or utilised offsite in other thermal processes.
Whilst the pyrolysis process itself its not a new concept, the skill is making such technology commercially viable. This will be achieved by developing a system that can handle 1 tonne of waste material per hour (over 8000 hours per year), proving that the gas produced can be reliably and efficiently used in a high efficiency turbo charged spark ignition engine and that the tars and chars produced as a by product of the process are marketable - thus, increasing the economics of such a scheme.
The plant is intended to operate continuously, 24 hours a day, with a target of achieving 8,000 operating hours a year.
