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Solar incineration of biomass for increased energy? Answered

Hi. I'm prototyping a solar energy system which basically collects, concentrates, and transports raw solar energy, and I'm thinking of various applications for it. My main interest is in water purification, but electricity is an obvious one as well, which means steam or, preferably, stirling engine generation. So say I had six square meters of sunlight concetrated into a light pipe and filling an insulated chamber. WIth losses that's going to be at least 5 kiloWatts of power, which is quite a bit and would run an engine pretty well. But what if you had some kind of combustable material in the chamber, like waste organic matter? It would burn, obviously, and release extra energy. And with the chamber full of extra heat largely in the form of light, I'm thinking you'd get a very efficient combustion of the matter and some ammount of the smoke. So, does anyone know if this would be worthwhile? Would the extra energy gained make it worth it? What would the emissions be, compared with just setting fire to it all? What happens to carbon at these kinds of temperatures? etc. Cheers!



9 years ago

Note that incinerating trash has been pretty politically unacceptable for a long time in most places, regardless of whether incinerator technology has improved enough to make it a real problem, or not. :-(

Mmm. Yes. No one wants great black clouds of smoke pissing out their neighbours back garden 24.7. So it looks like a couple kW of solar isn't going to make smoke go away, what will? How easy is it sequester your own carbon?

Brainstorming - If you heat your organic matter in an airless container, but with a vent to release pressure, would the waste be reduced to a kind of charcoal? Would that charcoal be a useful fuel? Would the gases driven off be useful? Perhaps the material would need drying first, so that the gases driven off would not be largely water.


9 years ago

isn't plasa going a bit too far? it would consume a lot of energy

. If you just want to reduce the volume and are not worried about destroying hazmat, then, yes, it can be done at much lower temps. Since he asked about "waste organic matter," I assumed he wanted to make the byproducts less hazardous.
. BTW, incinerating any organic waste just adds to the atmospheric CO2 problem. Incinerating organics at low temps produces some interesting chemicals (eg, furan and benzo*) that can be more hazardous than what you started with.

. To destroy most organics, you need to get to 2000-2100oF. At that temp, you basically have a plasma of disassociated atoms. You're end-products will be primarily H2O and CO2. Any halogens present will form acids, eg, HCl. Atmospheric N2 will result in NOx.