Hi All, Quick comment required here. if you've got hungry people in the neighborhood that's where the starch and sugars should go. Excess capacity that can't be transported to market, I'm fine with too. Cellulose works well (crop stubble)in anaerobic processes but first has to go through a hydrolysis step. (of course so does the starch just with different enzymes).
Tom -----Original Message----- From: Pannir P.V To: [EMAIL PROTECTED] Sent: 4/6/05 5:29 AM Subject: Re: [Biofuel] Fwd: [Bioenergy] Part 2 - Biogas from starch and sugar On Apr 6, 2005 1:20 AM, Leslie Young <[EMAIL PROTECTED]> wrote: > Very interested in your process, in N.A. applications. How can details of purchase / plans be accessed? > - Les. > ----- Original Message ----- > From: Keith Addison > To: [EMAIL PROTECTED] > Sent: Tuesday, April 05, 2005 1:59 PM > Subject: [Biofuel] Fwd: [Bioenergy] Part 2 - Biogas from starch and sugar > > >From: "Robert Deutsch" <[EMAIL PROTECTED]> > >To: <[EMAIL PROTECTED]> > >Date: Mon, 4 Apr 2005 00:12:35 +0700 > >Subject: [Bioenergy] Part 2 - Biogas from starch and sugar > > > >PART 2 (this message has been cut to conform to the file size > >requirements of the listserv) > > > >Production > >This system uses starchy or sugary material as feedstock. 1kg of > >sugar or starch yields about 400 litres of methane, within a period > >of 6 to 8 hours. This quantity is enough for cooking one meal for 5 > >to 6 persons. The biogas produced by this system contains > >theoretically about equal volumes of carbondioxide and methane, but > >in reality, it turned out to have less than 5% carbondioxide. This > >phenomenon is explained by the fact that carbon dioxide dissolves in > >the water in the fermenter vessel and diffuses out of it through the > >1 cm gap between the fermenter and the gas holder. > > > >We are getting about 250 g of methane per kg of flour. The values > >are approximations based on the volume of the gas and the crude > >analysis that was done in a chemistry lab. We are making > >arrangements with a government certified analytical lab for getting > >both the gas and the slurry analysed, and hope to come out with more > >reliable figures. The grain flour contains almost 10% protein and > >about half a percent of seed coat material, along with small > >quantities of fat in the embryo. > > > >Mr. Malar wanted to know the production potential of oilcake to > >methane. The biodigester working on oilcake of Madhuka indica > >actually uses 30 to 32 kg of oilcake (and not 16) to produce about > >15 cubic meters of methane. The time taken by this reaction is just > >24 hours. The weight of methane produced would be about 5.5 kg, > >having a clorific value of roughly 10,000 KCal/kg. > > > >[ From Nandu] Because of the residual oil and the high protein > >content of the oilcake, its calorific value is much greater than > >that of starch from cereal grains, rhizomes or tubers. As a result, > >this particular system is 1600 times as efficient as the > >conventional biogas plants. Another person, with whom we are > >collaborating, has a biogas plant producing daily 40 cubic meters of > >gas. He used to feed it daily with 1000kg dung, but now he is using > >daily a mixture of 200 kg cattle dung and 15 kg sorghum grain flour. > >He is reluctant to switch over completely to sorghum, as he feels > >that the bacteria may go on strike if they did not get their daily > >dose of dung. In his case, he replaces 800 kg dung by 15 kg flour > >and reduces the reaction time from 40 days to one day. He thus gets > >an efficiency that is 2000 times that of the traditional system. In > >the moving dome reactors that we use, the gas holder telescopes into > >the fermenter. Therefore, the total volume of the system is twice > >that of the volume of the gas that you expect to get from it. > > > >Starch, sugar, powdered oilcake, grain flour or powdered seed of any > >plant, take about the same time to digest and also produce the same > >amount of gas. It is likely that our high methane content is a > >result of a reaction 4H2 + CO2 = CH4 + 2H2O. Because very little > >work has been done by scientists on use of high calorie feedstocks, > >there is quite a lot of speculation about the high methane content > >that we are getting. > > > >Under our temperature and pressure, 1 cubic meter of biogas produced > >by a typical dung based biogas plant (50% each of CO2 and CH4) > >weighs about a kg. CH4 is about a third as heavy as CO2., therefore, > >in this case, 500 litres of CH4 would weigh about 250 g and the > >remaining 500 litres of CO2 would weigh about 750 g. I our case, we > >get almost pure methane, and it takes about 1 kg of flour to produce > >500 litres of it. Therefore we came to the conclusion that our > >biogas plant gives 250 g of methane per kg of feedstock. We haven't > >found much difference in different species of grain > > > >I wish to correct the figures of oilcake used and biogas generated. > >It takes daily about 30 kg oilcake to produce 15 cubic meters of > >gas. But this gas consists of almost pure methane. It is not a case > >of co-generation, but direct fermentation. Cattle dung was used only > >initially as a source of bacteria, but for more than a month, they > >are using only oilcake. > > > >I had never heard of the digestion accelerator, but would love to > >have it, if it is genuine. In any case, our biogas plant uses waste > >starch or sugar in any form. Thus spoilt bananas, oilcake of > >nonedible oilseed (e.g.castor or Jatropha), mango kernels, seed of > >practically any plant, rain damaged grain, etc. all work beautifully > >as feedstock. The material must be pulped or powdered. These > >substances are highly digestible and the methane production starts > >within a few hours after their introduction into the biogas plant. > >About 2 kg of dry matter in any of the above forms would yield about > >500 g of pure methane in about 8 hours. This period can be halved by > >heating the biogas plant. > > > >Advantages > >The short retention time and the small feedstock quantity enabled us > >to reduce the size of the gas plant. Our biogas plants have a > >floating dome that acts as a gas holder, whereby the dome is a > >plastic water tank that is available in the market. > > > >We have installed almost 100 biogas digesters operating on starch, > >and all are working without any hitch > > > >Even industrialists are interested in this technology, because the > >LPG for industrial use costs almost twice as much as LPG for > >domestic use. > > > >The retention time of dung in the dung-based biogas fermenter is 6 > >weeks, while that of starch is only 6 hours, which is why the volume > >of the fermenter could be reduced. The biogas produced from starch > >has about 60% methane by weight, while that produced from cattle > >dung has only 25% methane by weight. As a result even the 800 litres > >produced by my biogas plant is enough for cooking the meal of a > >family. We are trying to commercialise this new biogas fermenter. It > >costs only US$30 as against US$250 for the conventional biogas > >fermenter > > > >The gas produced by this system has thus almost the same calorific > >value as LPG. It burns without smoke or soot, producing an almost > >invisible bluish flame similar to that of LPG. > > > >This system is much easier to operate than the dung based biogas > >plant, because of the relatively small quantities of feedstock and > >effluent slurry to be handled. The effluent slurry generated daily > >by the plant is just a couple of litres. It can be used as manure > >for plants growing around the house. The 500 litre biogas plant, > >mass produced from moulded plastic drums, would cost about Rs. 3,500 > >(US$ 78). The smallest cattle-dung based domestic biogas plant costs > >about Rs. 12,000 (US$267). It requires daily 40kg dung, and owing to > >the retention period of almost 40 days, such plants have a minimum > >capacity of 2000 litres. They generate daily 80 to 100 litres of > >effluent slurry. Daily handling of such large quantities of > >feedstock and effluent is considered to be arduous and bothersome by > >users. > > > >The residual slurry of a biogas fermenter is a good organic source > >of plant nutrients, because the process of methane formation removes > >CO2 and CH4 from the biomass. Because of the selective removal of > >these elements form the biomass, the other constituents such a > >N,P,K,Ca, Fe, etc. get concentrated in residual slurry. > > > >The new system has a total internal volume of about 400 liters. Its > >small size allows the system to easily be accommodated inside the > >kitchen. It generates from 1 to 5 liters of effluent daily, which > >contains all the minerals in the original feedstock. Thus, the > >effluent can be used as manure. The prototype fermenter, in > >continuous operation for a year, has been successfully tested with > >various feedstocks such as waste flour collected from the floor of a > >flour mill, sugarcane juice, macerated sugarcane, leftover food, > >flour of no edible seeds, and powdered oilcake of no edible > >oilseeds. This technology does not rely on products meant for > >consumption by humans or animals. > > > >--------------------------------------------------------------------- > >------------ > >From: adkarve > >To: Robert Deutsch > >Sent: Thursday, March 31, 2005 11:44 PM > >Subject: Re: Text compiled from exchanges > > > >Dear Robert, > > > >I went through the extracts from the stoves list. I have no > >objection to any of the material being reproduced. However, some of > >it may need to be confirmed. The feedback from the users is that > >they would like to have more gas, about 1000 litres than the 500 > >litres that our present model delivers. This would raise the price > >of the gas plant by about Rs.1000 (US$ 22), if we purchased the > >existing water tanks for this purpose. We are however negotiating > >with a plastic manufacturer to get the tank at a lower price. We are > >also working on other feedstocks, which would be cheaper to use than > >the starchy or sugary feedstocks. I shall let you know about it when > >I a have the necessary data. > >yours > > > >A.D.Karve > > _______________________________________________ > Biofuel mailing list > [EMAIL PROTECTED] > http://wwia.org/mailman/listinfo/biofuel > > Biofuel at Journey to Forever: > http://journeytoforever.org/biofuel.html > > Biofuel archives at Infoarchive.net (searchable): > http://infoarchive.net/sgroup/biofuel/ > _______________________________________________ > Biofuel mailing list > [EMAIL PROTECTED] > http://wwia.org/mailman/listinfo/biofuel > > Biofuel at Journey to Forever: > http://journeytoforever.org/biofuel.html > > Biofuel archives at Infoarchive.net (searchable): > http://infoarchive.net/sgroup/biofuel/ > -- Pagandai V Pannirselvam Universidade Federal do Rio Grande do Norte - UFRN Departamento de Engenharia Qu’mica - DEQ Centro de Tecnologia - CT Programa de P—s Gradua¨‹o em Engenharia Qu’mica - PPGEQ Grupo de Pesquisa em Engenharia de Custos - GPEC Av. Senador Salgado Filho, Campus Universit‡rio CEP 59.072-970 , Natal/RN - Brasil Residence : Av Odilon gome de lima, 2951, Q6/Bl.G/Apt 102 Capim Macio EP 59.078-400 , Natal/RN - Brasil Telefone(fax) ( 84 ) 215-3770 Ramal20 2171557 Telefone(fax) ( 84 ) 215-3770 Ramal20 2171557 _______________________________________________ Biofuel mailing list [EMAIL PROTECTED] http://wwia.org/mailman/listinfo/biofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuel archives at Infoarchive.net (searchable): http://infoarchive.net/sgroup/biofuel/ _______________________________________________ Biofuel mailing list [EMAIL PROTECTED] http://wwia.org/mailman/listinfo/biofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuel archives at Infoarchive.net (searchable): http://infoarchive.net/sgroup/biofuel/
