Friday, February 17 was our fifth test burn with our improvised TLUD. We decided on another night burn to study flames in darkness, and capture more dramatic video of the gas flare.
On another balmy, warm mid-winter afternoon, Brad and I loaded the barrel with twigs and branches from the brush pile, plus a few thick stalks of Johnsongrass and thin slats of oak lumber. Most of the effort for a burn is to gather, prepare and load biomass.
We re-used the partly melted fiberglass insulation. It's thin and ragged, but even deteriorated, it serves to hold heat in the barrel and sustain a higher burn temperature.
We lit the TLUD after dark to harvest a new batch of nighttime burn videos. One particular I wanted was to study the gas flare in the dark to monitor the emission of sparks.
Normally, the persistent Kansas wind dies down in the evening, and we were nervous after the grass fire at the end of Burn #2. So, a night burn seemed a safe strategy.
However, on this night, just as we lit the TLUD, the wind picked up. Soon, 20mph gusts whipped the gas flare into 3-foot streamers of flickering flame just above my head. I watched nervously as sparks flew out horizontal at high speed.
|The Final Glow
bottom of the barrel & air intake tube
At least three times, strong, persistent gusts nearly extinguished the gas flare, forcing it inside the chimney cap. But even the wildest gust failed to create a downdraft strong enough to suppress or snuff out our gas flare.
The night wind was a true test of our wind shields on the chimney cap and air intakes. While not perfect, our wind shields performed very well under extreme conditions, and minimized the effects of wind on air intake, flame spread and draft. A metal skirt slipped around the cap can further shield the louvers to nearly neutralize wind effects on the gas flare.
Our burn was a special success. The burn went very smooth, and I could see, study and understand the gas flare more completely. I recorded some exquisite flame images with my digital camera.
This fourth successive successful burn gave us confidence we can master the efficient operation of this TLUD equipment. This method will also be easy to demonstrate and teach to others, and they will find it cheap and simple to make their own biochar, and explore its use in their own soilsÑand a dozen other uses.
Ultimately, these test burns will give us the insights we need to design and build a permanent TLUD at Four Oaks Farm that can steadily, easily make small biochar batches.
Learn to burn carbon-negative
Learn to live in the 21st Century
Co-create carbon accountable culture
|Blue Flames Dancing
up out of the barrel at the end of the burn