CircleDraft

West Biofuels offers a community-scale, modular, biomass gasification combined heat and power (CHP) system designed to convert biomass residues to renewable electricity and heat. West Biofuels has aggregated and refined proven commercial technologies to create a robust and scalable configuration that can meet energy needs ranging from 0.5MW and above.

System Components

How it works

The CircleDraft gasification combines components of traditional downdraft and updraft technologies to produce a raw producer gas with low contaminant loading, extending the life and reducing the cost of gas conditioning systems. This gravity-fed system contains four temperature sections including the drying zone, the pyrolysis and gas cleaning zone, the char stabilizing zone, and the char gasification zone. Like an updraft gasifier, air and steam are injected in the bottom of the gasifier in the gasification zone which generates the majority of the producer gas. Unlike a traditional updraft gasifier and more similar to traditional downdraft technology, the producer gas is directed into the pyrolysis zone where the gas is filtered through the pyrolysis char for initial cleaning before reaching the gas outlets and heat exchangers. In the pyrolysis zone, the char provides a course filter to capture the higher-chain contaminants. The char, along with any contaminant loading, continues through the char stabilization zone and to the gasification zone where the heavy contaminants are reintroduced to the high temperature zone to be further broken down. Biochar produced through this process is derived directly from the gasification zone without the introduction of contaminants via producer gas filtration.

System Specifications
Optimal Size
0.5 MWe – 5.0 MWe
Scalable Increments
0.5 MWe
Feedstock Specifications
Heating Value
> 7,000 Btu/dry lb.
Moisture Content
15% - 35%
Nominal Feed Rate
~2,000 dry lb./hr/MW
System Production
Gasifier Efficiency
65% - 80%
Generator Efficiency
28% - 36%
System CHP Efficiency
72% - 80%
Heat Availability
5.5 - 7.0 MMBtu/hr/MW
Biochar Production
200 – 300 dry lb./hr/MW
Syngas Heating Value
140 – 180 Btu/scf
Gas Composition
H2
18% - 22%
CO
14% - 18%
CH4
1% - 5%
CO2
11% - 15%
N2
46% - 50%
H2/CO
1.2 - 1.3
Tars
< 20 mg/Nm3
Tar Dew Point
15°C
contact us

Thank you! Your submission has been received!

Oops! Something went wrong while submitting the form