THE PAVER PLACE 

# WHITACRE 

# GRE R Q__u-a,lity SiiHe- 19 0 0 Mr. Jeff Telander Telander.Jeff@epa .gov Re : Comments for pre-SBREFA panel March 26, 2013

On March 141h I was in attendance at the pre-SBREFA meeting in Washington regarding the Brick MACT. I would like to thank you and your staff for that meeting . I believe it was very helpful to hear directly from Keith on where the MACT stands and the current thoughts . While the high cost of a traditional MACT was once again brought up, so was what we believe to be the more practical and affordable Health Based MACT. The industry model ing of the Health Based approach has results which show this is an acceptable, more practical way to proceed . We support the Health Based approach. I would like to respond to the request for comments, specifically sub-categorization and the differences between small and large kilns. I firmly believe that there is a significant difference between large and small kilns and that 10 tph is a reasonable breakpoint. You were able to use that level for sub-categorization previously and I feel that there is now a significant gap at this level and it should continue to be used . We have two small kilns in which we produce firebrick and pavers . In the past we have run our larger kiln at 8-9 tph. However, due to decline in sales we are currently running at 6.5 tph . The smaller kiln has not been run in years, but typically ran intermittently at 4-5 tph. The total emissions from an older kiln at 6.5 tph, or 4-5 tph should not be handled in the same manner as the emissions from a newer kiln at 25-30 tph . As outlined below, there are several design and operational differences between small and large kilns : 

### Firing. Both of our small kilns are fired using high velocity side burners . The burners are positioned at the very bottom ofthe car deck. The high air volume is used to churn the air around in the kiln . Even so, the temperature difference between the top and bottom is as much as 100 degrees . Larger kilns are top fired with a more even temperature distribution . 

### Car Size. Our kiln cars are narrow (6' wide) but higher (5 ' in our larger kiln, but lower in the small kiln) than new kiln cars, with a large space (1 ' ) down the center to aid w ith ai r flow . The two separate rows of hacks are done so very loose ly in several distinct columns, again to help with air flow. Typically the newer, larger kilns are of a low and w ide design , with the hacks continuing across and down the deck with much less airflow between . Doors. Our kilns were designed without being completely sealed . The exit end on our kilns have no door at all. You can see straight through the kiln , right down the 14 00 SouthMahonin gAve . Al liance ,Ohio44601 BOO WG PAVER P: 330.823.1 610 F: 330 .823 .550 2 in

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### open center, through the glowing fi re zone, to the entrance. While the entrance has a single door, no vestibule, it is not sealed in any way. It is there strictly to keep the heat from blasting out. When a new car is loaded, the single door is opened which changes the dynamics ofthe firing zones . These firing differences are part ofthe inherent appeal of our product. Kiln Construction . 

### The walls and ceilings ofthe smaller older kilns were designed with sizeable amounts of refractory bricks in the walls and the arched ceilings . The arched ceilings allow for considerable open spaces above the kiln cars, something not found in the large kilns . Large kilns are typically designed with a lighter fiber lined ceiling . The design and operational differences ofthe small kilns is what makes our product and colors unique . The addition ofAPCD to our kilns, along with be ing financially insupportable, would require a kiln redesign which would not allow for the same product to be duplicated . We continue to urge you to use the discretion afforded you and evaluate fully the Health Based approach along with sub-categorization at 10 tph . This approach fulfills the requirements ofthe Clean Air Act wh ile not putting a financial burden on the entire industry. S

incerely,

John E Miller, PE Engr/EHS Manager Whitacre Greer Co.