- Tar in the wood gas stream is considered a dirty gas and tar will gum up a motor quickly, possibly leading to stuck valves and rings. A new design known as the Keith gasifier improves on the FEMA unit, incorporating extensive heat recovery and eliminating the tar problem. Testing at Auburn University has shown it to be 37% more efficient than running gasoline. This system set the world speed record for biomass powered vehicles and has made several cross country tours.
- In some gasifiers this process is preceded by pyrolysis, where the biomass or coal is first converted to char, releasing methane and tar rich in polycyclic aromatic hydrocarbons. In stark contrast with synthesis gas, which is almost pure mixture of H2 / CO , wood gas also contains a variety of organic compound ("distillates") that require scrubbing for use in other applications.
- Size and shape: The size and shape of the wood can also affect the efficiency and emissions of the gasification wood boiler. The wood should be cut into small pieces or chips that are uniform in size to ensure even combustion and make reloading of fuel easier. Ash content: The ash content of the wood is another important factor to consider. Wood with a high ash content can increase the maintenance requirements of the boiler and reduce its efficiency.
Such details provide a deeper understanding and appreciation for Wood Gasification System Maintenance.
This structural setup is critical ... these systems offer. A rigorous Maintenance schedule includes daily ash removal, weekly inspection of turbulators, and annual cleaning of the heat exchanger and flues....
- Yo Richard. I found a link where you can download the plans on another page. Thanks for the heads-up tooI fixed the link. http://driveonwood.com/resources/pdf-articles/fema-gasifer-plans Have fun
Under normal circumstances the operator's role is limited to refuelling and maintenance. There is little need for action and virtually no risk of getting dirty. Start and operation can in fact be made fully automatic. Anybody expecting something similar for wood gas operation of engines will be disappointed. Preparation of the system for starting can require half an hour or more.
