New design updraft but not updraft gasifier

Hi there. What i have in mind is simple updraft wood gasifier but outgoing gas is not on the top but twenty cm above the air income or grate. And diameter of the reaction reduction zone would be ten to fifteen cm.numbers are just an example. and on the top of the hopper feedback pipe taking the tarry gas to the intake. A circulation from top to bottom to hot charcoal. This design would require continusly blower. Reason to do so is having a tar free gas by passing them throug hot charcoal, less char in ash if not none and cooler outgas temps thus more eficient.the thing to set would be flow of feedback circulation. This can be set to equal to max tarry gas production on full power because if it doesnt produce that much tarry gas it would just circulate some of the clean gas. My question here would be would gasifier have always tar free char in the reaction reduction zone. I mean could it turn the wood above the outgoing pipe in to clean char before the char in the reaction reduction zone consumed?exuse my english please.

Hello Ali,

Sorry but not sure I understand .

Why make tarry gas and then try to clean it . Best to make no tar to start with.

What efficacy are you shooting for ? Test we have done shows 37% more effect than gasoline .


If i could draw a picture will be easy to understand. And my english also a problem:( sorry. Let me work on drawing something i will try to post later. Efficiency i meant is gassifiers. Downdraft design is less efficient than updraft due to hot gas out.

“ Efficiency i meant is gassifiers. Downdraft design is less efficient than updraft due to hot gas out. “

Hello Ali,

We have no hot gasses out past the point of diminished returns. We even capture heat from the vehicle motor and put back in the gasifier. With that said the point of diminished returns will be different for each operator and his expense for fuel.


Hello AliG.
Not correct on your efficiency assumption. When the hot produced fuel gasses heat is Sensibly used to dry down the incoming fuel wood stocks a downdraft IS the most thermal efficient system of all for WOODFUEL gasification.

I understand very well your proposed consept.
You propose to take separately made smokey pyrolisis gasses and then power blower deliver them to a separately made bed of HOT glowing char.
This has been tried many, many different times in many different ways in the last 130 years. Most recently in the 2005-09 time period. Aways fails for some very practical reasons. To keep sticky, adhearing, coating smokey tars gases flowing they have to be kept HOT and non-condnesing. They WILL all systems passages, piping, blower impellors layer by layer tars, soota and ash coat and flows clog with each successive system warming up and system shutting down cycle phase. So from a practical operating standpoint it is best to keep the non-vaporizable products like heavy tars, wood char and ashes all kept HOT in close contact and able to gravity flow DOWN.
Once the fuels/airs moistures and fuel heat released long chain hydrocarbons are first in a compact physical and HEAT vertical linear system thermal-chemical reduced to the non-sticky motor fuel gases then it is THESE that are easily piped moved around with minimal clogging of only washable, brushable soots.
These whole systems operate on self-generted HEAT. Aways best to keep the internal heat generation and fuel gas heat absorbing conversions systems as closely coupled and compact as possible. THIS is what will soundly produce system efficiencies over any always will have heat energy losing separated out systems with more theoretical “advantages”.

Actual Fossil coal gasification for engine motor fuels as in vehicles WAS done much in 1930’s, 1940’s Europe. Pictured evidence done in Asia as in Japan, China and North Koera much later in the post WWII 1950’s to in North Korea even into the late 1990’s.
VERY dirty, toxics condnesates, ash and air emitting end products.
Japan has some of the strictest laws applicable about many pollutions in the world. And they rever thier trees. Why they buy out most of their wood products overseas from The US/Canada, Russia and SE Asia.
Be careful about the local in-country legality of any of your creations. Once you reach hard learned sucess and this is recognized then the local energy supplier “toes you stepped on” will use thier native countries laws to paint you as a foreigner, a danger, a hazard.

Steve Unruh

Thanks for the warning sir steve. I should have mensioned that i am not planing to do these in big scales in japan. Seeing is believing. Today i am taking home a fire extinguisher i think its arround ten liters. And will try wood gasifier updraft but not updraft:)