Design of downdraught gasifiers
The downdraught gasifier makes it possible to use wood as fuel and produce a gas with sufficiently low tar content to operate an internal combustion engine. There are other means of handling the tar problem but these may create their own problems. Fox example, use of charcoal as fuel involves a loss of energy and increases the risk of depletion of wood resources. Use of cleaning systems after the gasifier involves difficult waste disposal problems.
Down-draught gasifiers being comparatively easy to build and operate, are likely to be the most appropriate for developing countries as a source of decentralized power supply to rural communities and industries.
The conversion of solid fuel to gas in a down-draught gasifier and the design basis for such gasifiers will therefore be examined in more detail.