February 15, 2023
New Emission Limits Proposed for Lime Manufacturing NESHAP
Though EPA finalized its risk and technology review (RTR) for the lime manufacturing NESHAP on July 24, 2020 (85 FR 44960), not all hazardous air pollutant (HAP) emissions were addressed. In Louisiana Environmental Action Network vs. EPA (U.S. Circuit Court of Appeals, D.C. Circuit; Docket No. 17-1257; April 21, 2020), the court held EPA must address unregulated emissions from a major source category during a standard’s periodic review.
When the agency collected emissions data for the 2020 RTR, it found lime kilns emitted unregulated HAPs, including hydrogen chloride (HCl), mercury, organic HAPs, and dioxin/furans (D/F). On January 5, 2023, EPA proposed amendments to the Part 63, Subpart AAAAA air toxics standard. [88 FR 805] The amendments include a set of emission limits for these unregulated pollutants and operating parameters for the associated emission control equipment. Comments may be submitted through February 21, 2023 via Docket ID No. EPA-HQ-OAR-2017-0015.
Emission Limits
In 2017, EPA prepared a questionnaire to collect information on the lime kiln industry. The industry reported on the location and number of lime kilns, types and quantities of emissions, annual operating hours, types and quantities of fuels burned, and information on air pollution control devices and emission points. The collected data indicated that HCl, mercury, organic HAPs, and D/F are emitted, but unregulated, HAPs. Though the agency conducted a “beyond-the-floor” MACT analysis, it did not identify any techniques that would achieve greater HAP reductions than the new and existing source floors. Consequently, the proposed emission standards are based on the MACT floor. Additionally, total hydrocarbon (THC) is used as a surrogate for organic HAPs. The proposed numerical emission limits vary depending on the type of kiln used and the lime produced, as shown in the table below.
Summary of Proposed New and Existing Source Limits for the Lime Manufacturing NESHAP
Pollutant1 | Kiln type2 | Lime produced3 | New source limit | Existing source limit | Unit of measure |
|---|---|---|---|---|---|
HCl | SR | DL, DB | 1.6 | 2.22 | lb/ton lime produced |
QL | 0.021 | 0.58 | lb/ton lime produced |
||
PR | DL, DB | 0.39 | 0.39 | lb/ton lime produced |
|
QL | 0.015 | 0.015 | lb/ton lime produced |
||
VK | All | 0.021 | 0.021 | lb/ton lime produced |
|
Mercury | All | QL, DL | 24.9 | 24.9 | lb/MMton lime produced |
DB | 24.4 | 33.1 | lb/MMton lime produced |
||
THC | All | All | 1.86 | 3.21 | ppmvd as propane @7% O2 |
D/F | All | All | 0.028 | 0.028 | ng/dscm (TEQ) @7% O2 |
ng/dscm = nanograms of pollutant per dry standard cubic meter of air; ppmvd = parts per million by volume, dry; TEQ = toxic equivalency
1Hydrogen chloride (HCl), total hydrocarbon (THC), dioxin/furans (D/F).
2Straight rotary (SR), preheater rotary (PR), vertical (VK).
3Dolomitic lime (DL), quick lime (QL), dead burned dolomitic lime (DB).
Source: Adapted from 88 FR 815.
Demonstrating Compliance
Affected sources that commence construction or reconstruction on or before January 5, 2023 would be considered existing sources and have three years after the effective date of the final rule (or upon startup, whichever is later) to comply with the provisions of this rule. Affected sources that commence construction or reconstruction after January 5, 2023 would be considered new sources and must comply with the provisions of this rule by the effective date of the final rule (or upon startup, whichever is later). The effective date of the final rule will be its promulgation date. [88 FR 816]
New sources must demonstrate initial compliance with the new emission limits within 180 days after startup, while existing sources must do so within three years of the final rule’s promulgation. Subsequent performance testing would be required every five years thereafter. Continuous compliance with the emission limits would be demonstrated through control device parameter monitoring coupled with periodic emissions testing. New operating parameters are proposed for three types of control devices: activated carbon injection, dry sorbent injection, and regenerative thermal oxidizers.
Facilities will be required to submit semi-annual compliance summary reports documenting compliance and any deviations from the standard. Records of this report and the calibration and accuracy checks on the continuous parameter monitoring system will also be required. [88 FR 815]
©2023 McCoy and Associates, Inc. All rights reserved.
McCoy and Associates has provided in-depth information to assist environmental professionals with complex compliance issues since 1982. Our seminars and publications are widely trusted by environmental professionals for their consistent quality, clarity, and comprehensiveness.
Disclaimer
Considerable care has been exercised in preparing this document; however, McCoy and Associates, Inc. makes no representation, warranty, or guarantee in connection with the publication of this information. McCoy and Associates, Inc. expressly disclaims any liability or responsibility for loss or damage resulting from its use or for the violation of any federal, state, or municipal law or regulation with which this information may conflict. McCoy and Associates, Inc. does not undertake any duty to ensure the continued accuracy of this information.
This document addresses issues of a general nature related to the federal RCRA regulations. Persons evaluating specific circumstances dealing with the RCRA regulations should review state and local laws and regulations, which may be more stringent than federal requirements. In addition, the assistance of a qualified professional should be enlisted to address any site-specific circumstances.
