Thermochemical Conversion

Involves the use of heat and chemicals, to convert biomass into other forms of energy. Thermochemical conversion requires multiple stages and is typically used for converting biomass into fuel gases and chemicals. During the first stage, solid biomass is converted into gases. Then, during the second stage, the gases are condensed into oils. Lastly, in the third stage, the oils are conditioned and synthesized to produce syngas. Syngas can be used to produce lubricants, ammonia, and biodiesel, and it contains carbon and hydrogen. 

Gasification involves the use of relatively high temperatures and a controlled environment that leads to nearly all of the biomass being converted into gas. This takes place in two stages: partial combustion to form producer gas and charcoal, followed by chemical reduction. These stages are spatially separated in the gasifier, which would have a design much dependent on the feedstock characteristics. Gasification requires temperatures of about 800°C. Gasification technology has existed since the turn of the century when coal was extensively gasified in the UK and elsewhere for use in power generation and in houses for cooking and lighting.