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- up Hector.Ybanez to: Keith Barnett 09/17/2010 02:31 PM Show Details
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Keith During our August 31, 2010 meeting we discussed numerous issues and as part of that discussion we identified some follow
- up items. Follow
- up items included (i) article regarding the design of wet scrubbers to control HCl and SO2; (ii) Clinker production; (iii) Calculation of 30
- day rolling average expressed in lb per ton of clinker; and (iv) the alternative PM limit for combined sources.

HCl and SO2 have different optimum pHs where maximum adsorption occurs. For example; the optimum pH for HCL is between 2 and 3 and the optimum for SO2 is about 7. Therefore, it is possible that EPA’s assumption; that any SO2 scrubber will additionally control HCl emissions to the degree necessary to meet the final standard. The second item deals with measuring clinker production. This is an i mportant issue to the cement industry. For instance, each plant is equipped with specific measuring devices (i.e. weight feeders) to determine the daily production. In accordance with CORPORATE guidelines, if the difference between the measured value and the value calculated based on the Monthly Inventory Verification Process is 5% or greater the plant must calibrate the measuring device. This is how many (if not all cement manufacturing facilities) complete their month end closures. My concern is that t he final promulgated rule is written with no realization of the operational realities. To that end, EPA should clean
- up this matter as part of its efforts to improve the Final Rule. However, in the meantime, I think that this can be accomplished using an alternative monitoring request. Would you agree with that approach? On the third item you asked for our opinion of how to best calculate a 30
- day rolling average. We would agree that each 30
- day average is bestcalculated by dividing the total ma ss of pollutant emitted in 30
- days by

the total mass of clinker produced in 30
- days. The fourth major item deals with the alternative particular matter (APM) limit. The final rule describes the situation when there is an alkali bypass associated with a k iln, the combined PM emissions from the kiln or in
- line kiln/raw mill and the alkali bypass stack are subject to the PM emissions limit of 0.04. Existing kilns that combine the clinker cooler exhaust with the kiln exhaust for energy efficiency purposes an d send the combined exhaust to the PM control device as a single stream may meet an alternative PM emissions limit. This limit is calculated using the following equation:

PM alt = 0.004 x 1.65 x (Qk + Qc)/7000 However, the industry contains numerous other plant configurations not addressed by the final rule. For instance, several plant configurations include the following: a. In - line kiln/raw mill, alkali bypass, and in
- line coal mill b. In
- line kiln/raw mill and in
- line coal mill c. In - line kiln/raw mill, alkali bypass, in
- line coal mill, and cooler Holcim believes that the above configurations should be allowed to use the above equation to establish an alternative PM limit. Item “c” above fits the definition in the final ru le with the exception of the in
- line coal mill. The in
- line coal mill can use hot gases from the kiln or the cooler and Holcim recommends that depending on the configuration Qk or Qc should include airflow volumes associated with the in
- line coal mill. I tems “a” and “b” above are configurations where the clinker cooler vents to the atmosphere however because of the in
- line coal mill we believe that the appropriate alt PM limit equation is: PM alt = 0.004 x 1.65 x (Qk + 0)/7000 Where Qk would include those sources listed in items “a” or “b” associated with the kiln and in that case Qc would equal zero. Qc would equal zero because the cooler in such configurations is vented to atmosphere. I think that this can be accomplished usi ng an alternative monitoring request. Would you agree with that approach? Let’s discuss these issues once more if you need any additional clarifications. Thanks (See attached file: HCL and SO2 Scrubbers.pdf)_____________________

Hector Ybanez Corporate Manager, Environmental 122 West Carpenter Freeway Suite 485 Irving, Texas 75039 Phone (214) 524
- 2814 Cell (972) 268
- 1139 Hector.Ybanez@holcim.com hybanez@gmail.com www.holcim.com/us This e
- mail is confidential and intended only for the use of t he above named addressee. If you have received this e
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