Simple Biochar retort or oven -seeking designs or plans #technology #kiln #pah

Kobus Venter

Hi Kim,

Unfortunately not. PM2.5 also not predicted. It would be useful to know PM in micrograms per cubic meter (μg/m3). I guess it can be converted if anyone is up for it?



On Sat, 10 Oct 2020, 20:14 Kim Chaffee, <kim.chaffee2@...> wrote:

Also, do you have the particulate emissions in micrograms per cubic meter (μg/m3).  I assume the testing company didn’t measure PM2.5.  Thanks.


On Oct 10, 2020, at 1:34 PM, Kim Chaffee via <kim.chaffee2@...> wrote:

Hello Kobus,

Thank you for that very helpful data and video.  Do you have the gas pollutant results in parts per million or billion (ppm or ppb)?  This information would be helpful for scaling the results to other size kilns.  Thanks.

Kim Chaffee

On Oct 10, 2020, at 12:17 PM, Kobus Venter <kobus@...> wrote:

Hi all,

We have had the emissions emitted by VUTHISA kilns tested by AIRSHED. Results attached. Emission rates and factors were not available so use was made of emission factors for charcoal kilns as reported by Pennise et al (2001), primarily and US EPA AP42. 

Point Source Emissions ~  Maximum Hourly Release Rate

From left to right:

Pollutant Name|mg/Nm³|mg/Am³|Emissions kg/hr 

CH4 (a) 936|319|0,25
CO2 (a) 37816|12876|10,0
N2O(a) 3,2|1,07|0,0008
CO 4680|1593,00|1,25
NO 11,8|4,0|0,0031
NOx 13,2|4,5|0,0035
PM(b) 638|217,00|0,17
PAH(c) 0,07|0,023|0,000018
VOC 1943|662|0,52
(a) Greenhouse gas
(b) Minimum emission standard for PM, 50 mg/Nm3
(c) Minimum emission standard for PAH, 0.1 mg/Nm3

VUTHISA kilns uses after burning to reduce emissions. The US EPA states that afterburning is estimated to reduce PM, CO and VOC emissions by at least 80%. The above fugures includes the 80% reduction.

Thought that may be of interest.

Here is a video of the process:




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