"What's the difference between having the tank opening at 3/4" on the one hand, and having the pump itself stepped down to 3/4"? Do you think giving the oil a head-start to build up some speed (and pressure?) in a length of 1" pipe will make any difference? I don't know (though I doubt it), I'm asking."
The difference is in the pressure drop along the length of pipe (50% difference). The 1 inch to 3/4 inch step down will create approximately the same pressure drop at the pump or the tank, but the friction in the pipe will change based on the size of the pipe and where it is. Andy On Thu, 10 Feb 2005 23:49:37 +0900, Keith Addison <[EMAIL PROTECTED]> wrote: > >I have a 1" clear water pump hooked up to an eighty gal hot water heater. > >I used all 1" plumbing for my manifold with 1" full port valves. > >The tank opening is still 3/4" but there should be ample pressure > >pushing the oil through the opening. > >How long should I have to run the processor to get full reaction? > > > > Thank you, Jeremy > > You're referring to this? "Re: New method for the production of home > made bio-diesel": > > ><snip> > > > >>I am building the Appleseed reactor and so far I have spent about $200 on > >>lab gear (glass ware, pH meter, scale, etc.), and three steel 55 gal drums. > >>Still looking for a suitable 50-60 gal water heater for which I will most > >>likely spend $50 - $100 from a local used plumbing shop. If you have a > >>recycled construction materials yard there that would likely be a good > >>source for wood or steel for racks and frames as well as the plumbing > >>supplies. I have decided to go new on the pump and vacuum pump since it > >>would be difficult to determine the actual condition of used one. Beside, > >>you may not know what it had been used for which might introduce > >>contamination into your process > > > >Be aware that the 1" clear water pump usually recommended for these > >reactors is too small for that size water heater. Those pumps will > >handle at most a 25-gallon reactor. So you'll have to extend the > >processing time considerably to get a complete reaction, or use a > >bigger pump. Or at least try using the 1" clear water pump at its > >full 1" capacity, rather than stepping it down to 3/4", which will > >probably mean changing the fittings on the tank. > > > >Also be aware that the arrangements on these processors for draining > >the glycerine by-product do not achieve good separation and you're > >quite likely to get some glyc along with the biodiesel to be washed > >in the wash-tank, compounding the washing problems you'll have if > >the process isn't completed properly. > > > >So don't just blindly follow the instructions as it seems most > >people building these reactors do. Think about it yourself, figure > >it out, step by step. > > > >Best wishes > > > >Keith > > 80 gallons is definitely too big for that pump when it's fitted as > recommended by the people who promote those processors, ie, stepped > down to 3/4". I'd say it's also too big for it at 1", especially as > you have a 3/4" inlet. > > I don't understand this: > > >The tank opening is still 3/4" but there should be ample pressure > >pushing the oil through the opening. > > What's the difference between having the tank opening at 3/4" on the > one hand, and having the pump itself stepped down to 3/4"? Do you > think giving the oil a head-start to build up some speed (and > pressure?) in a length of 1" pipe will make any difference? I don't > know (though I doubt it), I'm asking. > > >How long should I have to run the processor to get full reaction? > > I don't think there's any formula that can tell you that, there are > too many variables. For instance, we might tell you something that > was correct for an 80-gallon tank using that pump that we happened to > know of (though we don't), but if your tank had different dimensions > (say short and fat rather than tall and thin) it probably wouldn't > work. You'll have to find out by trial and error. Use these tests: > > Quality testing > http://journeytoforever.org/biodiesel_vehicle.html#quality > > I'm not knocking the pump, by the way, we use one, for 60 litre > batches, and it's great. I probably am knocking the people who > recommended it for use with 200-litre tanks and more - and then > kicked up huge unseemly smokescreens of denial and obfuscation when > it was suggested here that it was too small for such a tank... only > to admit it very blithely four months later on another list, as if it > all the fuss they'd made here had never happened. Yuk. Too much ego, > not enough of what makes people human, IMHO. > > Best wishes > > Keith > > _______________________________________________ > Biofuel mailing list > [EMAIL PROTECTED] > http://wwia.org/mailman/listinfo.cgi/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.cgi/biofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuel archives at Infoarchive.net (searchable): http://infoarchive.net/sgroup/biofuel/
