Obvious sources of biomass for gasification can be found in agriculture.<br>Here in Vietnam most rice hulls, rice straw and coffee husks are either dumped or burned.<br>Vietnam, for example, produces annually about 8.2 million tons of rice hulls and 54 million tons of rice straw.<br>
We do not have to consider producing biochar from trees when such huge agricultural biomass is so readily available.<br><br>In the gasification of rice hulls, rice straw and coffee husks,<br>the big value, by far, is in the gas that is produced.<br>
For example, one kg of rice hulls produces about $0.21 in gas but only about $0.07 in biochar.<br>In other words, biochar comes in at only one third of the value of the gas.<br>Biochar production therefore is a by-product of gas production.<br>
But if the the rice hull can be obtained, as is usually the case, free-of-charge,<br>and if biochar can be sold at a nice profit,<br>then gas is produced at a negative cost.<br>Also note that when rice hulls are properly gasified,<br>
no smoke is produced.<br>So in producing gas, one earns a profit in the sale of biochar.<br>The big economic driver in this instance is the production of gas.<br><br>There are people in Vietnam who know nothing about the value of rice hull gas,<br>
and they are busy each day making rice hull biochar in crude retorts.<br>These low-temperature retorts emit clouds of smoke that can be seen from miles around.<br>Focusing only on biochar production, these people do a lot of damage to the environment and should be shut down.<br>
The biochar that they produce is anything but uniform.<br><br>For more on this, see: <br><a href="http://dl.dropbox.com/u/22013094/Paper/park.pdf">http://dl.dropbox.com/u/22013094/Paper/park.pdf</a><br>See the section on gasification starting on page 79.<br>
I am a big believer in utilizing a multiplicity of approaches with regard to biomass.<br><br>Thanks.<br>Paul Olivier<br>Vietnam<br><br><div class="gmail_quote">On Wed, Oct 12, 2011 at 6:40 AM, Steve Taylor <span dir="ltr"><<a href="mailto:steve@thetaylorfamily.org.uk">steve@thetaylorfamily.org.uk</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><br><br><div class="gmail_quote"><div class="im">On 11 October 2011 17:55, Fireside Hearth <span dir="ltr"><<a href="mailto:firesidehearthvashon@hotmail.com" target="_blank">firesidehearthvashon@hotmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div><div dir="ltr">
Dear Steve,<br><br> I spent most of my adult life teaching people how to heat their homes without smoke coming from the chimney, when I see pictures of areas where bio char is being made I see horrible air pollution from the fires,<br>
</div></div></blockquote></div><div><br>I see "biochar" being used as an excuse for burning to clear land rather than the emissions generated being considered pollution from the process of making it. <br><font color="#888888"><br>
Steve <br>
</font></div></div><div></div>
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<br></blockquote></div><br><br clear="all"><br>-- <br>Paul A. Olivier PhD<br>27C Pham Hong Thai Street<br>Dalat<br>Vietnam<br><br>Louisiana telephone: 1-337-447-4124 (rings Vietnam)<br>Mobile: 090-694-1573 (in Vietnam)<br>
Skype address: Xpolivier<br><a href="http://www.esrla.com/" target="_blank">http://www.esrla.com/</a><br>