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6

The bacteria in the muck in cold lakes that produce swamp gas live at cooler temperatures ~0-20 °C. Here's an account of the gathering of psychotrophiles from lakes near Mount Everest. Note that you will still want to avoid temperature swings - insulate fermenters. Also, the retention times needed at lower temps are far longer. With long retention times in ...


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I have been pursuing this problem for many years and I have come up with a viable solution that I have developed from my 10 years of research and commercial application. I have developed a system called SSTCS-"Synergistic Sustainable Tumble Culture System" that can take eutophic water from point source pollution from effluent or no point pollution that ...


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exploring the problem I've asked around on the Claverton Energy Group for some help on this. Thanks to John Baldwin, I learnt that biogas tends to be about 65% methane, with a lot of carbon dioxide, and some oxygen and hydrogen sulphide. Whereas gas as supplied for industrial, commercial and residential use is 90%+ methane, plus gases such as propane and ...


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Carbon dioxide release occurs when compounds containing carbon are oxidised. In conventional aerobic decomposition, this process is relatively direct and carried out by a range of organisms. In a biogas digester, whilst there is no initial release of carbon dioxide, it is released when the resulting methane is burnt. At the end of both processes, you are ...


3

Let's see: This paper states numbers for organic waste production from 0.14 - 0.32 kg/ person day for developing countries. Elsewhere it is said that the total amount of organic wastes differs little between high- and low income countries, but the composition changes: More kitchen scraps, peelings etc. in low incom countries vs. meal leftovers in high ...


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First of all, EROI depends on the calculation method (what is included and excluded), on the production method, and on the used resources. This means that there isn't one uniform EROI for biogas. It can vary from researcher to researcher and from site to site. This also means that it's often possible to find very positive and very negative numbers, depending ...


2

If you are going to use wood gas to run a generator, don't bother removing the CO. Burn it. https://www.youtube.com/watch?v=X3KipK49v7g is a vid on making a woodgas powered truck. That said: Consider getting a manual transfer switch, and a gas or diesel powered generator. While the power may have been off for 10 days this time, I found in our (shorter) ...


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This master's thesis by Dahiru Rufai Ahmed at the university of Oulu provides a comprehensive background into the removal of CO2 from wood gas. On pages 36-37 it mentions the water-gas shift (WGS) reaction as a method of adjusting the hydrogen/carbon monoxide mixture or removing CO entirely to get pure H2. "The WGS reaction is an exothermic reaction (∆Hr ...


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I can only answer regarding the actual plant. If food wastes need to be trucked all around Sweden when the incinerator is down the road, the picture may be different. Biogasification of food wastes, market wastes and similar stuff is certainly better, for the reason you describe in your last paragraph: Kitchen wastes are typically 70-80% moisture. ...


1

Any organic material decomposing in a anaerobic or near anaerobic situation will produce methane. I question your assumption that the source in landfills is mostly food in origin from individuals. Other sources: Processing waste -- All those corn husks, apple pulp from making applejuice. Grocery store waste -- imperfect veggies, old food. Yard waste. Grass ...


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First, how do we look at the biogas yield of a suvbstrate? We look at the total solids (TS) and volatile solids (VS), and then measure the gas production per VS. TS is the fraction that remains after thorough drying, while VS is the fraction that is lost after heating the dry stuff to a few hundred °C for an hour or so. VS is a handy stand in for the part of ...


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Yes, you could. Biogas production is heavily depending on outside factors. If you have to haul the matter a significant distance, you may end up with a net loss. Biogas overall is a way to intercept some energy that would otherwise be lost. Remember too, that biogas is mostly methane. If your system leaks, then you are replacing the CO2 that the ...


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