Home / Gasification Technology / What Is Pyrolysis?

Pyrolysis Of Biomass

When biomass is subjected to high temperatures in the absence of oxygen it is transformed into solid char, gas and bio-oil.  The solid char is called “Biochar” and is widely used in agriculture as a soil conditioner.  The gas is a synthesized gas called “Syngas” which is used for electricity generation.  The bio-oil can be refined and transformed into bio-fuels.  This process is known as “Pyrolysis” which is nothing else than a thermal decomposition converting any carbonaceous material in different forms of energy.

There are two types of pyrolysis: Slow and fast.  Slow Pyrolysis also known as “carbonization” occurs under a slow heating rate, normally 120-200 degrees Celsius, and it has been used for thousands of years mainly for the charcoal production.  Fast Pyrolysis or “Thermolysis” uses a higher temperature range, between 400 and 500 degrees Celsius for a shorter period of time, normally 1 to 5 seconds.

The results of Slow Pyrolysis are 30% bio-oil, 35% biochar and 35% syngas.  Fast Pyrolysis on the other hand produces 75% bio-oil, 12% biochar and 13% syngas.  Depending on the desired final product, slow or fast pyrolysis is selected.