Fluidization

[Alan]

I have been experimenting with the 18mm glass roasting tube to see why it produces such smooth vapor and have determined that I am creating a glass fluidization chamber. http://en.wikipedia.org/wiki/Fluidization
The Volcano, Herbalizer, and Cloud also utilize a fluidization chamber arrangement which is one of the reasons they work so well. Air corn poppers and coffee roasters use fluidization to ensure uniform roasting temperature. It makes sense that it would work well for vaporization since all you are doing is roasting a herb. Getting the air to spin like a corn popper should provide the most effective extraction (need to work on that).
The roasting tube is the second half of a vaporizer and every bit if not more important than the heat unit.
A fluidizing tube will improve the effectiveness and flavor of the vaporizer system. A glass chamber is the most ideal for taste.

 

[Hippie Dickie]

i concur ... i find a 18mm tube to be smoother/cooler than a 12mm tube. i think the vapor expansion coming out of the heater section causes this effect. i recently got some 25mm tubes to see if that is even better (or not) ... just sitting in a cabinet right now, since i haven't gotten around to drilling any glass tubes for a while.

 

[HoneyAir]

Does the herb fly around in the chamber like popcorn does in a popper? If so, that is quite the ultimate stirring method! Stirring the bowl with a stick will seem so crude in comparison.

 

[Alan]

Does the herb fly around in the chamber like popcorn does in a popper? If so, that is quite the ultimate stirring method! Stirring the bowl with a stick will seem so crude in comparison.

Between hits the herb mass cools and sticks together. I have found that if I quickly start and stop the air flow, it will shake and break up the herb mass until it is a uniform thickness. The herb pops up and down and bounces around while you do it. I am also able to blow back into the roasting tube to clear the material from the second screen.

I have been able to create fluidizing tubes from 13mm x 10mm glass tubing and also 5/16" ss tubing. Wine corks hold the 13mm x 10mm glass tubes together. Cork is also used to hold the 5/16" ss tubes together.
The 18mm glass roasting tube still has the best flavor since it has the best air flow.

 

[vap999]

I recall Bob (commonly attributed as the Eterra/log-style vaporizer "inventor") at his Web site (Flashevap.com; page could still be there) explaining how he was inspired to develop his first vaporizers after inspecting a city waste incinerator, with this a very large-scale fluidized bed. Yes, a fluidized bed would be highly efficient, and is something to strive for, good for inspiration.

But fluidized beds are not conducive to small-scale applications (although a wood fire that goes to glowing floating burning powder, drawing fresh air from below, is an example). This technology, even a wood stove, operates as a continuous process, requiring air flow (often driven by heat from combustion) through the bed/herbal particles and a good amount of space above the bed to allow for particle settling. With herbal particles too light weight and fluffy to be held down in a bed by gravity alone (in a fluidized bed), with use of a herbal-retentive screen/filter required (with a convection vaporizer), this makes true fluidized bed (no retentive filers) herbal vaporizers a likely unattainable goal.

 

[Alan]

Bob is like the godfather of vaporization. Very practical application of vaporization on a small scale.

I may not be getting true fluidization, but it is working so much better than traditional combustion based methods.