sizing up an afterburner

[Gila]

I'm looking for an afterburner setup that would basically zero out smoke and odor for an Ambex YM-2 [at present] and an Ambex YM-10 or YM-15 [in the future]. When talking to thermal oxidizer fabrication companies, I'm asked for an exhaust SCFM number as a starting point for the design. I called Ambex, but they do not know SCFM numbers for these smaller models. Is there any general correlation between roaster capacity and SCFM number? Are there any good afterburner reference materials out there?

 

[topher]

Wow...afterburner for a 2.5 kilo? Why are you required to do this?

 

[seeingcoffee]

You will first need to check with the government agency that regulates emissions in your area. They will provide you with very specific criteria you need to meet with respect to particulate matter levels, residence/dwell times, operating temperatures, etc. The afterburner (referred to as a thermal oxidizer in the industry) for a 10 kilo roaster is going to be considerably different than one for a 15 kilo roaster. There will be a considerable price difference between the two. To spec the proper afterburner, you need to provide the manufacturer with information regarding roasting chamber temperatures, exhaust flow in cubic feet per minute, and BTU output of the roaster's burner. There will be a considerable variation between 10 and 15 kilo roasters. Also, you need to determine whether you have adequate natural gas supply and pressure to run the afterburner. Keep in mind the afterburner uses a considerably higher amount of fuel than the roaster. Most burners on afterburners that meet my local air quality mandates require natural gas pressure of 1/2 psi or 14 inches above water column. This would require most commercial sites to upgrade to a medium pressure gas system.

Just a few thoughts to consider when sizing an afterburner. It is not as simple and straightforward as most people think. Hope this helps...

 

[chast]

Contact Craig. This guy is great to deal with and knows what you will need.
Thermal Afterburners For Coffee Roasting Systems

 

[seeingcoffee]

Contact Craig. This guy is great to deal with and knows what you will need.
Thermal Afterburners For Coffee Roasting Systems

Yes, Craig is the guy!

 

[Gila]

Wow...afterburner for a 2.5 kilo? Why are you required to do this?

No requirement as of yet but we'd be operating with a conditional permit in a dense commercial area with lots of foot traffic on the edge of a neighborhood. I was thinking a 'no loss' stack head and/or booster fan might also work for now, but I'm not sure if that smoke might come down somewhere nearby depending on wind/weather.

You will first need to check with the government agency that regulates emissions in your area...

I've confirmed that there are no formal local or state emissions regulations at this scale, so it's just a question of perceived smoke and odor. Thanks for the rundown; I was wondering about the gas supply.

Contact Craig. This guy is great to deal with and knows what you will need.

Thanks - will do

 

[Gila]

Craig is a _fantastic_ resource, but it sounds like a fairly high-ceilinged space is required to fit his smallest afterburner (~11 - 12ft ceiling).

Investigating alternatives brings me to a question: the Coffee-Tech Avirnaki air cleaner claims to allow a 2KG roaster to roast without any outdoor ventilation whatsoever. The roaster exhaust duct just goes into the Avirnaki box and - voila - clean, warm air exits into the room. The roasters that Coffee-tech cite in their sales pitch for the Avirnaki are their electric 'Solar' 2KG and 'FZ-94' 2.4KG models. However, what happens with a 2KG natural gas or propane fired roaster hooked to an Avirnaki venting into a room? Would it even be allowed in a commercial setting?

 

[seeingcoffee]

I think you might be looking for a "good neighbor" afterburner to allow you to roast without being a nuisance. Many roaster manufacturers make this. I know Toper does. They are reasonably priced and do not use much fuel. There is also a device called the Thermo Stack. This is a smoke stack with an embedded burner. For my geographic location and with regard to its respective air quality standards, we ran the calculations and determined it was only able to service a 15 kg or less roaster, so it might be perfect for you. It was too small for us. This device runs under $10K and uses about 300,000 BTU.

 

[Gila]

I have a call into Thermostack, but Toper politely declined: "We are sorry to inform you that we are not able to supply these afterburners for machines other than Toper."


Can anyone comment on the effectiveness of odor elimination between these two approaches: A.) a thermal oxidizer B.) an electrostatic filter + carbon filter device?

 

[WajihSadad]

Omg why you need it !!

 

[Musicphan]

You may want to call US Roasters and see what they have available... I believe Dan makes one for their 3K.

 

[ellatas]

Craig is a good resource for Afterburners of this size. Since he only deals with Afterburners, he will be able to guide you to the correct size. And I wouldn't bother getting a separate Afterburner for the Sample Roaster as it could be directed into the Afterburner for the larger Roaster.

 

[slurp]

I have a used afterburner for sale, it is for a 60 kilo. Sure it will cover a 2.5 kilo and you have room to upgrade.

 

[Gila]

UPDATE: Thanks to everyone, but we've gone the other direction and found a location where it looks like we'll be fine without any smoke elimination.