Downdraft Gasification
Downdraft gasification is much like updraft gasification; it involves a similar setup that contains high temperature regions (anywhere around 700-1000°C) that will convert the fuel of the process to syngas. The feed for the process of gasification can be many things, such as coal, pelletized material, wood chips, etc. The main difference between downdraft and updraft gasification is that the air and the fuel flow in the same direction for downdraft; the syngas from this process will tend to have lower tar content than updraft gasification, however the design for the reactor tends to be extensive, and small particle size feeds are not converted well.
Flow Diagrams
(Source: http://maribelajarlistrik.blogspot.com/2011/12/sistem-pembakaran-batubara-di-dalam.html)
(Source: http://gasification.ueuo.com/technologies.html)
(Source: http://agronomyday.cropsci.illinois.edu/2010/tours/c3chips/)
Equipment
Videos
Downdraft Wood Gasification Barrel Stove
2nd Generation Downdraft Stratified Biomass Gasifier
Gasifier (downdraft), Internal Examination Video part 1 of 3
References
- http://www.jfe-eng.co.jp/en/en_release/news_03030.html
- http://www.chamco.net/Gasification.htm
- http://www.springvale.biz/course%20notes/week11%20Biomass%20wood%20combustion1/week11.htm
- http://www.nariphaltan.org/gasbook.pdf
- http://en.wikipedia.org/wiki/Gasification
- http://www.youtube.com/watch?v=C1nUC1e07OU
- http://www.youtube.com/watch?v=ceLu3h5SkXM
- http://www.youtube.com/watch?v=2sCFpCpSTqE