From: Garth Tayler [mailto:gtayler@brick.com] 

Sent: Friday, April 10, 2009 1:47 PM

To: Marinshaw, Richard

Cc: Susan Miller (E-mail); Jason Pence

Subject: RE: Information on Periodic Kilns

Rick

Please see my responses to your questions below. Please feel free to call for further discussion on this.

It can be seen from the engineering studies we have done, that the process variables with these round 

kilns makes it extremely difficult to determine a representative emission rate.

Thanks

Dr.Garth Tayler

Technical Director

Acme Brick Company

Fort Worth, Texas.

(817) 870-8354 (office)

(817) 907-1208 (mobile)
-----Original Message-----

From: Marinshaw, Richard [mailto:rjmarinshaw@rti.org]

Sent: Thursday, April 09, 2009 1:51 PM

To: Garth Tayler

Subject: Information on Periodic Kilns

Garth,

I left you a voicemail but thought it would be easier to pose my questions in an email. Basically, we have

three questions:

1) For the tests on the three periodic kilns, the emission factors for the Ft. Smith kiln are much lower 

than the factors for the Bridgeport and Milsap plants. Do you know why the Ft. Smith kiln emissions are 

so low?

We are dubious about the FTIR engineering study that was done in January 10 -12, 2003 . Studying the 

methodology used by the stack testing firm, we see that each of the measurement periods taken 

to determine the average were not the same and not evenly spaced through the firing cycle. This 

could have resulted in a lower average reading. 

We have data from an engineering study stack test carried out at Fort Smith, using Method 26A, on 

October 6 - 9, 1992. The plant configuration at that time was different. The plant had 6 smaller 30 foot 

round kilns in use. (These were replaced 1999 - 2000, with three larger 42 foot kilns). 

This ealier stack test was carried out on one of the 6 kilns, by taking 18, 1 hour readings, at 

approximately 2 hour intervals, over the duration of the firing cycle. The average HF and HCl emissions 

rates per hour were seen to be about 2.2 times higher. (HF 1.25lb/hr and HCl 0.0905lbs/hour, compared 

to 0.502 lbs/hr and 0.041lbs/hr respectively for the 2003 test on the 42ft kilns). Furthermore, the brick load 

in the smaller kilns was nearly half that of the large kiln (157 tons versus 288 tons). 

2) The time-temperature profiles you provided to us run through the end of the firing cycle, but what 

happens then with respect to temperatures? I assume that the kiln cools down for several hours before 

the fired bricks and shapes can be removed.

Yes, the kiln cycle moves into the cooling phase. During the cooling phase the air supply to the burners is 

increased to maximum (gas is ofcourse is shut off), the exhaust is increased to maximum, and a large 

panel fan is placed in front of the open kiln door to provide further cooling air to the kiln. The cooling cycle 

takes 16 to 24 hours, depending on the production rate of the plant.

3) The FTIR data indicate that HF emissions can still significant at the end of the kiln cycle. Do you 

have any information on what happens to emissions after the kiln cycle ends?

Will the rapid drop off in temperature and the high rate of air dillution that takes place when the cooling 

phase is started, the HF and HCl emission decreases to vitually zero instantly.

We appreciate your help with this.

Thanks

Rick Marinshaw

Richard J. Marinshaw, P.E.

Research Environmental Engineer

RTI International

3040 Cornwallis Road

P.O. Box 12194

Research Triangle Park, NC 27709-2194

Phone: 919-316-3735