UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION I

JOHN F. KENNEDY FEDERAL BUILDING

BOSTON, MASSACHUSETTS 02203-0001

SEP I 3 1995

Sarah R. Anderson

Division ofLicensing and Enforcement

Bureau of Air Quality

Depal1ment of Environmental Protection

Stale House Station No. 17

Augusta, ME 04333-0017

Re: Alternative NOx RACT for Dragon Products Company. Inc. in Thomaston, Maine

Dear Ms. Anderson:

Thank you for the opportunity 10 review the proposed alternative NOx RACT for Dragon

Products Company. Inc.. in Thomaston, M::line. The enclosure cont::lins Ollr detailed comments.

Please enter these comments into the public record. IfYOlI have any comments on the enclosed.

please contact Steven Rapp of my staff at (617) 565-9024.

Sincerely,

David B. Conroy. Chief

Ozone Programs OOice

Enclosure

cc: Bryce Sprolll, ME DE?
Enclosure:

EPA Comments on the Proposed Allemative NOx RAeT for Dragon Products Company,

in Thomaston, Maine

1. Process and Combustion Modifications: For miscellaneous and alternative RACT

determinations, Chapter 138.3.1 requires a company to submit an analysis of various options for

the reduction of NOx to the atmosphere. Specifically, the regulations require that the company

submit, "an examination ofthe technical and economic feasibility of available NOx control

techniques for the applicable NOx emitting eC]uipment for which alternative RAeT emission limits

are sought, including but not limited to... i. Low NOx Burners, ii. Overfire air, iii. Flue Gas

reburn, iv. Burners out ofservice, v. Use of alternative fuels-, vi. Selective non-catalytic

reduction, vii. selective catalytic reduction, and viii. Alternative operating scenarios."

However, the application and proposed license fi'om Dragon Products Company (Dragon) contain

only a limited analysis ofselective non-catalytic reduction, selective catalytic reduction, and a

number of process and combustion modifications. It is not cle'H to EPA why other potential NOx

reducing technologies for cement kilns, such as 10w-NOx burners/staged combustion, have not

been included in Dragon's analysis. The applic(jtion and proposed license describe Dmgon's kiln

as having an average clinker production of 55 IOns per hour with a capacity heat input of

approximately 263 MMBtu/hr. The EPA's "Alternarive Contra! Techniques (ACT) Document--

NOx Emissions From Cement Manufacturing (EPA-45J/R-94-004; March 1994)," discusses lowNOx burners at indirect fired long wet kilns, with capacity of 50 tons clinker per hour and 300

MJv1Btu/hr, as having a cost effectiveness of$230 per ton of NOx removed. According 10 the

proposed license, Dragon has already converted the kiln from n "semi-direct" 10 an indirect-coal

firing combustion system Therefore, Dragon's RACT anC"llysis should include an analysis of

technical and economic feasibility of using low-NOx burners/staged combustion at the Thomaston

facility.

Also, given that the application also mentions a current feClsibility study for burning tires in the

kiln, EPA suggests that Dragon's analysis include this as a potential NOx redllction technique.

The ACT shows similar facilities with mid-firing of tires as having a cost effectiveness of$430 per

IOn of NOx removed, Additionally, with the recent proposal of the Open Market Trading Rule

for Ozone Smog Precursors (see 60 FR 39668, August 3, 1995), EPA is strongly encouraging

States to consider discontinuing the issuance afsource-specilic vari<lIlces for f<lcilitles where

discrete emission reductions are available and economically feClsible. Therefore, all future

requests for compliance extensions and alternative emission limits, sllch as for Dragon, should

include in their analysis of control options the potential use of discrete emission reductions to

comply with the otherwise applicable emission standard (see 60 FR 3968S, section Ill.e.6 of the

preamble). Since the RACT compliance deadline has (llremly passed, EPA believes that it is

reasonable to re{]uire Dragon to submit the nnfllysis of these additional options within the next 90

days.
2. RACf Conclusion: The proposed license states that, "The only reasonably available control

technologies for the reduction ofNOx are process and combustion modifications." As discussed

in comment #1, EPA does not agree that Dragon's RACT analysis is complete. Furthermore, the

proposed license states that, "Dragon instituled many of these control technologies in advance of

the RAeT analysis...which have resulted in NOx emissions 20% below the average for wet

process kilns an~ emissions reduced to 60% of tile facility's maximum potential-uncontrolled NOx

emissions." EPA agrees that the combined effect of these modifications will reduce fuel use at the

facility and may indirectly reduce NOx. However, the RACT analysis should provide an estimate

of the reduction in the actual NOx emission rate from a 1990 baseline. RACT is generally

considered a reduction of the actual NOx emission rate ofa unit of 30 - 50% from 1990 levels.

3. Emission Standards/Order: The proposed license lists an interim NOx emission limitation of

800 Ibs/hr for any hour period, 335 Ibs/hr expressed as a 90 day rolling average, and 1467 TPY.

Yet, it is unclear how these interim limits were derived. The interim emission limit should be

based on the expecled reduction from the approved controls. However. it is unclear ifany

reduction is being required from the unit since the control analysis seclion of the proposed license

lists the maximum hourly emission rate as 732 Ibslhr, yet Maine is allowing Dragon a hourly NOx

emission rate of 800 Ibs/hr.

Additionally. the proposed license allows Dragon to propose a NOx emission limitation by May

31, 1997. However, it is unclear to EPA why the facility, already equipped with a NOx

monitoring system, needs almost 2 years to perform adequate testing! monitoring and propose an

emission limit. This delay in assigning an emission limit amounts to a 2 year RACT compliance

date extension. EPA does not agree that such an extension is warranted. EPA believes that it is

technically and economically feasible for Dragon to perform the testing and propose a limit within

four months oflhe issuance of the final license or, l'lfter Ihe dale ofinstallmion of low-NOx

burners, if they are shown to be feasible in the analysis discllssed in comlllent # I.

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