Mentioned above was a hot filter Ben added later, I bought his books, but never saw that afterwards. Any one have that?
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Hi Al F.
You mean his example of a conversion shown to a hot filter shown on the 3rd edition books page 216?
You’d never see this change once done.
It is a vertically pleated center drop in-insert into the standard filter can. Using as a couple of the Sweed guys use: welding blanketing as the material.
Book page quote,
“Clean with a shop vac or just a light brushing to remove fine carbon dust. Produce the cleanest gas and service in just minutes”
“Some new users have problems using this tight of a filter, so I recommend getting some hours on the gasifier before switching to this. When you are actually putting solid hours on an engine, then make the switch. Some reconfiguration of the gas flow will be necessary, but pretty easy.” Ben Peterson.
Does this answer your question?
S.U.
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I’m building one of Ben Peterson gasifiers and for the hot filter do you run the gas through hot filter before the cooling tubes? And also why are people having trouble with it?
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You run into problems with a hot filter when the gas is too moist, you want to preheat the system before the filter to get it good and hot.
When the gas isn’t hot enough the moisture makes the soot and carbon clod up and reduce flow.
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So you would heat the system then drop in the filter?
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Have a tapping point for your starter blower right before the filter, start up right there until you’re at a good operating temperature. Then close that tapping point off and run the blower where it normally would be on a Peterson.
You could have a Tee off point with a valve to close it off.
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There are a lot of “Depends” when you would hot filter the Ben’s Book system JoshL.
A Hot filter must be kept gasses hot above condensation point or you will wet and then flow clog the filter media.
But the gas must be pre-cooled enough to not heat damage the blanketing material used.
Here is a for’instance. Say you were Ben’s book system built just as in the book woodgas fueling a 4 cylinder industrial Ford or GM water cooled electrical generator. These are 8-12kW electrical.
Summer temperatures that single pass zig-zag tube cooler might not cool the gas enough before the filter can when the generator system is under a high AC or water well pumping loading. You cook embrittle the filter fibers. Tears allowing unfiltered gas flow.
Same system in cool, cold winter might over cool the produced gas then sending wet gas into the filter can making soot mud clogging your filter blanket. Poor gas flow. Poor power.
A small only 500cc electrical gen-set would probably always run gas too cooled wetting never letting the hot filter to work.
A 240-300 cid six cylinder big Onan gen-set might always run too gas hot.
Others using hot filters do set up for all gas flaring bypassing until gas temps are high enough. Mistakes happen.
Others will close couple the Hot filter directly out of the gasifier lower. Then at high system loadings and a grate activation while under this loading can pass thru red hot hot char embers. These can and have lit-off the soot cakes on the hot filter surfaces.
Hot filters and mistakes can happen. You must be an aware better Operator for the better filtered gas.
On a Ben’s book system for hot filtering I’d add on a thermal sensor switch system from a vehicle with the electric auto type fans able to force cool the gas cooler tubes.
If I lived in a cold, cold climate I’d roller shade type have a pull-up cooler cover. Had these from the factory on all of my early Volvo cars. This could be temperature sensor automated too.
The basic book system is set up for a don’t care can get wet filtering. Ha! Ha! maintain your wife’s bagless Shark vacuum and study their three stage filtering for effectiveness ideas.
Temperature and moisture resistant sheep’s wool layers first. Thick open cell foam next. Final pleated paper filter.
Joni and Tone picture here on the DOW doing this on their all-in-one big can/barrel filter systems successfully. And they both do a basic cooler pass thru first, also.
Regards
Steve Unruh
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Thanks for the input! I plan on running 300 4 cylinder engine on it i don’t have a power head yet for it but I’m hoping for 15 kw
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So it seems this of grid48 guy and ben are really having it out this Kind of stuff really sucks I hope they come up with some sort of agreement. Anyways do you sell the automation kits on a website? I would really like something like that system on mine when i finish putting it together and run some tests first
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Hi Josh,
For your automation, just get these cycle timers for your grate and hopper shaker. You dont want to know what I would charge for a full blown automation package. This system cost as much or more than some of our gasifier systems.
Use this controller to set up timed intervals to agitate your grate and hopper. If you are running a stationary system then this will be predictable and somewhat linear.
If you want the AFR system there is DIY thread hear on the forum. If I were to build this system alone you are looking at $1200 bucks just to give you an idea. Guys I hire to wire and build this stuff are expensive; it takes a couple days just to build and wire one of these boxes. These guys get $25 to $30 bucks an hour plus the $400 in parts and material’s cost and then our margin.
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Ok thanks I appreciate it and keep up the good work!!
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