Gasification is a termochemical conversion of carbonaceous materials (biomass) into combustible gases. This is achieved by reacting the material at high temperatures with a controlled amount of air or mixture of oxygen with steam, depending on the use of the generator gas.
The main product of gasification is a generator gas (syngas) containing the gaseous components of H2, CO, CO2, CH4, H2O, N2, hydrocarbons and higher boiling pyrolysis products (tar) and a solid residue often containing a certain amount of carbon, dust and other compounds.
The gasifier is atmospheric, unique downdraft configuration. The gasification of the biomass is divided into zones in the gasifier – drying, pyrolysis, oxidation and reduction. The main advantage of this type gasifier is the production of syngas with low tar content for IC engines.
Output Parameters
Power plant electrical output per one gasifier line*
600 to 710 kWe
Parasitic electrical load
up to 12%
Power plant electrical efficiency – feedstock to energy
32,0 %
Thermal energy generated at outside ambient temperature of t = 0°C
600 to 710 kWt
Feedstock consumption at heating value of 8 MJ/kg and MC of 50 %
0.85 – 1.00 tonne/h
*The gasifier can also be operated at lower power
Higher electrical and thermal output is achieved by parallel arrangement of gasifier lines, i.e. syngas generators and IC engines.
Syngas Parameters
Syngas chemical composition
H2
~ 20-25%
CO
~ 15-30%
CO2
~ 5-15%
CH4
~ 1-3%
N2
~ 40-50%
Syngas chemical composition
LHV
~ 5,0 to 6,5 MJ/Nm³
Feedstock Parameters
Wood chips
Average heating value
10.0 (8 to 12) GJ/tonne
Average moisture content
30-50 %
Feedstock preferred size
Fuel particle size of 8 to 80mm (ideal size of 50x50x20mm) Maximum particle size – length 100mm, thickness 25mm (up to 10% of total volume) Minimal particle size – 8 mm (up to 10% of total volume)