Dear Paul, Palm Kernel shells are very good fuel. They contain a lot of fixed C. Even they are burnt in a stove of natural gas, the flame is very clean and hot with flame mixing of blue and pinkish color.
Please check the video: https://www.youtube.com/watch?v=g7TZn6YGOcI Have a nice week end. Kind regards M. Nurhuda > Yesterday I received some palm kernel shells from Malaysia, and proceeded > to run them through my 150 TLUD of only a 25 cm height. > > The gasification of the palm kernel shells looked like this: > http://www.youtube.com/watch?v=IDFHPjLx08A&feature=youtu.be > I am not so happy with this result: too much of an orange flame. > But I am not sure of the moisture content of these shells, and I doubt > that > they were in the ideal 10 to 12% range. > > When I mixed in some rice hulls with the palm kernel shells, the flame > looked like this: > http://www.youtube.com/watch?v=N_sI4zKUuq8&feature=youtu.be > This represents a remarkable improvement in flame color. > > I am trying to understand why rice hulls have they effect that they have, > either when processed alone or in conjunction with some other material. > There is the initial combustion reaction that provides a lot of heat to > the > process. This reaction gives rise to a lot of CO2. But the water gas > reaction, the water shift reaction and the methane reaction do not convert > this CO2 into CO. It appears that there is only one reaction that can do > this: the Boudouard reaction where C + CO2 gives CO. > > Let us suppose that if the biomass is at 10% moisture content and if the > AER is at 0.3, the temperature at the combustion reaction reaches 800 C or > more. According to what I have been able to understand from Tom Miles, it > is at this temperature that the Boudouard kicks in. But if the gas expands > quickly and cools off after the combustion reaction, the Boudouard > reaction > will not take place. So we end up with a dirty gas full of CO2. > > But if rice hull char situated above the gasification front provides a lot > of resistance to the flow of gas and does not allow the gas to expand and > quickly cool off, then it could be possible for the Boudouard reaction to > take place, even in a small TLUD. When CO burns, it does so with a blue > flame, and if enough CO is present in the gas, the flame color is a rich > blue. > > If there are relatively large spaces into between the palm kernel shell > char above the combustion zone, the gas quickly expands and cools off: no > Boudouard reaction and a lot of dirty gas is produced. > > Does this make sense? > > Thanks. > Paul Olivier > > > -- > Paul A. Olivier PhD > 26/5 Phu Dong Thien Vuong > Dalat > Vietnam > > Louisiana telephone: 1-337-447-4124 (rings Vietnam) > Mobile: 090-694-1573 (in Vietnam) > Skype address: Xpolivier > http://www.esrla.com/ > _______________________________________________ > Stoves mailing list > > to Send a Message to the list, use the email address > [email protected] > > to UNSUBSCRIBE or Change your List Settings use the web page > http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org > > for more Biomass Cooking Stoves, News and Information see our web site: > http://stoves.bioenergylists.org/ > > _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org for more Biomass Cooking Stoves, News and Information see our web site: http://stoves.bioenergylists.org/
