The oxygen free decomposition of raw organic materials into gas due to an elevated temperature is known as pyrolysis. In the gasification process pyrolysis occurs converting raw materials containing carbon into a combustible gas containing mainly carbon monoxide, methane, hydrogen, and tars.

This basic process takes place in a gasifier which is a chamber where the air flow, fuel flow, and temperature can be controlled. Furthermore steam can be added to control the gasification process. In the Pyroneer Gasifier pyrolysis takes place at a lower temperature than normal gasifiers. Once gas has been produced in the gasifier it can for example be used for power production through a traditional combustion process. The differences between combustion, traditional gasification and low temperature gasification are illustrated below.



Combustion: Equal amounts of air and fuel are converted into mainly CO2 and heat, where the heat is utilized for power production and district heating


Traditional biomass gasification: Fuel and a limited amount of air are mixed in the gasifier, generating a combustible gas. Biomass is in general gasified in a Circulationg Fluidised Bed (CFB) gasifier operating at 850-950°C. This however prohibits the use of high alkaline containing materials as agricultural leftovers and energy crops (e.g. straw and mischanthus). Due to the high temperature the ash in the biomass will melt, and the traditional CFB-process will be blocked due to agglomerating bed material. The nutrients in the melted ash, will not be available for the crops, and cannot be utilised as fertiliser.


Low Temperature Gasification: Fuel and a limited amount of air are mixed in the gasifier, generating a combustible gas. Due to the low temperature it’s possible to use high alkaline containing fuels as the gasifier operated below the melting point of those, and furthermore the nutrients remain in a usable form.