The process takes place within an enclosed environment, meaning there are no emissions to air or water, and converts waste into oil and gas, which can then be re-used to generate electricity and heat.
The waste materials are fed into the system, first entering into a ‘primary hopper’, which is a chamber where they are purged with carbon dioxide to ensure no oxygen remains, and then passed into a ‘secondary hopper’. The two hoppers are isolated from each other to ensure no excess oxygen is transferred.
Advanced Thermal Conversion
From the secondary hopper the material is transferred into a conversion chamber which is maintained at a temperature of 850ºC, where a pyrolysis reaction takes place and the material in converted into hydrocarbon gas and carbon ash.
There are then two exits from the conversion chamber. One is where the residual carbon ash is collected for disposal – this waste is around 10 per cent of the original volume fed into the plant. The second exit is where the gas is passed into a condenser, so that it can be cooled, and pyrolysis oils are separated out, before being filtered to remove any carbon material.
The final products are:
- Oils that can be used for a standard light oil burner, or to fuel a reciprocating engine or turbine for the generation of electricity and heat
- Gas that can be used to produce electricity using a standard gas powered combined heat and power generator.