Hi Keith and All, --- Keith Addison <[EMAIL PROTECTED]> wrote: > Hi Thomas > > >Hey, just a thought, but since it appears that the > most readily > >produceable biofuel is methane from digesters, > maybe this bears more > >discussion. > > You won't say that when your digester leaks some air > and explodes, > and the, um, feedstock hits the fan! While possible it's not probable. With the exception of the first 3 days until the digester gets going the inside will be under pressure a little and the main gases present would be methane and CO2 and under 1% O2 . The danger in the first 3 days can be eliminated by putting Co2 in the airspace. It should be outside and 1 way gas valves used in the supply line. >I'm not so sure > it's the most > readily produceable biofuel, I think it's quite > troublesome. IMHO > both biodiesel and ethanol would be simpler, if it > came to a choice > and all things were equal (which they seldom are). Methane is the most readily producible biofuel. Digesters are a fair way but for volume on demand is Destructive Distillation of wood without O2 is much better. This puts out about 70% methane, 20% H2, methyl gas, ect that can directly run gas engines and burners. An engine made to run on this / natural gas has eff equal to a diesel and little pollution. An eff engine would have a 13 to 1 compression ratio and a long stroke. While this is great for home use for car use you have to store it to 3000psi. This wastes about 25% of the energy and the containers are heavy though they have recently made some light ones by using carbon fibers. In an accident 3000 psi could be very dangerous. The easist liquid biofuel is methanol or wood alcohol. This is made by taking the output of the DD process and while keeping it at 700/1000 deg F and run it thru a copper tube with copper chor - girl for catalyst inside it. The output is mostly methanol alcohol. While this was done to make fuel a lot 1890 to 1938 this is the only technic to make it I've found so far. I found it in Home Power #21 page 55 to 63. I joined this list hoping to learn more about this. Bad points are fairly toxic though biodegrades fast so good handling is nessasary and has only 40% of the energy of gasoline While wood wastes will be free for many years here in Fla after biodiesel ,a great fuel, becomes popular it's main feedstock, used fryer oil will become more costly. Also there are wastes left over to get rid of. Ethanol is a great fuel but not easy at all to make. Due to the large amount of leftover mash unless you have cows or another hi-value use for them it's too ineff. Time start to finish is weeks and needs a lot of volume. Has 60% of gasolines energy. Ideal would be a method to turn DD gas or methanol to ethanol. This would be the best of both worlds and should be possible. I hope to learn how to do this.
>I'm right with you that biogas needs more discussion > on the list, > there's been very little, and it certainly > qualifies? I agree!! > We don't talk much about woodgas either (producer > gas). Nor about > using straight vegetable oil as diesel fuel. While biogas from digesters , methane and CO2, is a clean fuel wood gas ( producer gas)is anything but clean. It's mostly N2, CO2 , CO, H2 and many nasty things like benzines, creosote, ect. Only 1/3 of the gas burns so you lose 50% of your engine power and gunks it up. DD gas is much better and almost as easy to make and much easier to clean. I like straight veg oil as much less waste. From what I hear starting on and finishing on biodiesel or reg diesel relieves most problems. > >Exactly how difficult/expensive is it to compress > methane > >to the point where it could be used with standard > propane fuel systems? > >Isn't propane/butane a mixture of biogasses? Very expensive equipment and 25% of the energy to compress it. You use it like nat gas. One nice thing is CO2 goes liquid first and can be drawn off. I've heard that cooling is a more energy eff way to to densify these gases rather than compression. I will use mine at low pressure with a little storage for starting the engine and the exhaust to heat the DD process to make more gas to run it on. Charging my house and ev batteries is my goal. Also a liquid fuel for the ev's take along genorator for unlimited range. Propane / butane are longer mol chains of HC so compress easier. Slightly more pollution but much better than gasoline. Converting biomass to these would be good but ethanol is better. At least one company is changing methane to a liquid but stringing methane atoms into a chain for use as a liquid diesel fuel. I'd like to learn how this is done. > I think many or most of us are using wastes - WVO > for biodiesel or > any number of wastes for ethanol. If we didn't use > them they'd either > foul up the landfills and/or the water systems, or > just go to waste > (eg windfall fruit in a pigless orchard). Optimising > waste-use could > produce immense amounts of energy with zero loss to > anyone and great > gain to everyone in environmental improvements, > apart from more > diversified energy supply and lower fossil-fuel use. Converting wastes is where the cheap energy is. What we need are good processes to do it. I believe that in 3 years energy costs will 2 to 3 times what they are now so I'm getting ready now. Thanks, jerry dycus > I think it had better be, if there's going to be > one! Happy holiday to you too. > > Best wishes > > Keith Addison > Journey to Forever > Handmade Projects > Tokyo > http://journeytoforever.org/ > __________________________________________________ Do You Yahoo!? Yahoo! Shopping - Thousands of Stores. Millions of Products. http://shopping.yahoo.com/ -------------------------- eGroups Sponsor -------------------------~-~> Download Net2Phone's free software to make FREE calls anywhere within the US from your PC now! Get great low rates on international calls! http://click.egroups.com/1/10923/0/_/837408/_/977761863/ ---------------------------------------------------------------------_-> Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html To unsubscribe, send an email to: [EMAIL PROTECTED]