About old times ... I once visited the Imbert works in Arnsberg in the late 70ies. They had begone to work on gasifiers again after a long time. That was a result of the 1. oil shock. They built V4A gasifiers mainly for South America as i was told. The production was modern for those days. I had a chance to meet Dr. Ide, one of the fathers of the Imbert design during WW2. He must have been in his late 80ies than. I remember him grabbing me by my arm and leading me away from the guided tour to a small room in the basement where he made some research of his own. He said : "Young man, what do you want this old rubbish for (the downdrafts), it was obsolete even in those old days!" And then he showed me his fluidized bed garbage and bark gasification system and the wonderful flame it turned out. "This is the future" he said. "There will never be enough good wood for the downdrafts !"
Rolf Am Samstag, 25. September 2010 01:45:15 schrieb doug.williams: > Hi Jim and Colleagues, > > This is certainly a rare glimpse of the past, even if it is glamorised just > a tad. > > http://www.youtube.com/user/bioenergyken > > >there are some interesting things to see in the video. in particular, > >between 2 and 3 minutes, there is a quick shot of how the imbert did > >its grate shaking. bear and i are currently rather interested in this > >question and doing lots of testing to characterize the impacts of > >different shaking mode types and different grate hole sizes. > > In my visits to Germany where I had a chance to talk to old men users, the > shaker was important for start-up to have fresh porous char in the > reduction zone, and to refresh this grate char bed support on each > refilling. > > >as we all know, bell packing is a major challenge for long untended > >running. needing to poke a rod down the rig every once in awhile is > >unacceptable for untended genset operation. expert operators of car > >rigs tend to do this regularly, and don't think much of it. for a > >newbie or a regular run situation, you need to eliminate the knowledge > >dependency that only the expert has so they know when and why to do > >this. > > The Imbert design, and any other that draws the gas up around the sides, is > prone to plugging in the central core, and channelling down the sides of > the reduction zone bed as the gas takes the shortest route out towards the > source of suction. A pyramid of solidified char and fines form on the grate > quickly after start-up, then all the gas forces it's way out down the sides > often resulting in channels. > > >the imbert apparently had the side shake design via a pivot point > >going through a gimble ball. this is a mode i was playing with in the > >phillipines given challenging fuel there. now we're trying to > >formalize the performance of this vs vibrator, vs in/out shake vs > >rotary. oddly, we're finding up and down motion to potentially be more > >effective than side to side or rotary motion. i thought such would > >contribute to packing above. but so far it seems to do the opposite. > > The up and down shake we have used since 1977, but the issue of any shaking > is that it disturbs the char evolution right through the bed from top to > bottom. Any shake should only be used to clear a stray stone or clinker, as > actual bed disturbance can results in a total loss of CO2 reduction., and > of course a slug of tar coming through. Engine vibration > is good, but can cause packing of the bed, if the motion is vertical rather > than horizontal. Our experience has shown over many trials of fuels, that > shaking is not going to give you a good quality gas with any high ash fuel > that needs shaking to keep the gas flowing. > > Hope this is of some assistance, > Doug Williams, > Fluidyne Gasification. > > > > _______________________________________________ > Gasification mailing list > [email protected] > http://listserv.repp.org/mailman/listinfo/gasification_listserv.repp.org > http://gasifiers.bioenergylists.org > http://info.bioenergylists.org > > UNSUBSCRIBE HERE; > http://listserv.repp.org/mailman/listinfo/gasification_listserv.repp.org _______________________________________________ Gasification mailing list [email protected] http://listserv.repp.org/mailman/listinfo/gasification_listserv.repp.org http://gasifiers.bioenergylists.org http://info.bioenergylists.org UNSUBSCRIBE HERE; http://listserv.repp.org/mailman/listinfo/gasification_listserv.repp.org
