http://www.gekgasifier.com/forums/ en Thu, 09 Sep 2010 18:29:11 GMT vBulletin 5 http://www.gekgasifier.com/forums/images/misc/rss.jpg http://www.gekgasifier.com/forums/ http://www.gekgasifier.com/forums//showthread.php?t=434&goto=newpost Tue, 07 Sep 2010 23:00:37 GMT Rice hulls and straw are becoming one of the largest agricultural waste residues in the world. Due to the high ash content (18-30%, of which up to... Rice hulls and straw are becoming one of the largest agricultural waste residues in the world. Due to the high ash content (18-30%, of which up to 90% is typically of silica content, which can create clinkers) and the lower void space of the bulk material, the gasification of rice hulls requires engineering consideration separate from that of other types of woody biomass such as shells, softwoods, etc.

There are two aspects of rice agricultural residues that I am curious about: what are the volatile constituents, and what is the effect of steam gasification on clinkers?


First, I have been curious that maybe rice does not need the higher combustion temperatures needed by wood due to possibly a lower volatile content or at least the type of volatile constituents in rice? IF this is the case, which im yet convinced, then it would be convenient due to glassing of silica at higher combustion temperatures.

Second, the article that characterizes the glass/char complex (posted here: http://gekgasifier.pbworks.com/Rice-Hulls-and-Straw)suggests that there is some frequency of Si-OH surface groups which create a more hydrophillic characteristic of the glassy/char, clinkers. Since Si-OH could be considered a termination step of the formation of [-Si-O-]x glassy structure that yields clinkers. Because of this notion it might not be to far off to think that steam would prevent the formation of clinkers by possibly adding -OH and also lowering temperature. This may or may not be the case.

I am curious what other experiences have been either running rice residue gasifiers, testing of pyrolysis gasses, or characterizing glassy/char complexes that make rice hull/straw gasification a challenge. ]]> Biomass Types and Characteristics JayAlchemAPL http://www.gekgasifier.com/forums//showthread.php?t=434