FINAL NESHAP FOR LIME MANUFACTURING PUBLISHED
EPA has finalized the Lime Manufacturing National Emission Standard for Hazardous Air Pollutants (NESHAP) on January 5, 2004 (69 FR 394). This rule applies to facilities that own or operate a lime manufacturing plant that is located at, or is part of a major source of hazardous air pollutants (HAPs). A brief summary of the rule follows:
Determination of Major HAP Source
The EPA is requiring that all lime manufacturing facilities potentially subject to the final NESHAP demonstrate, with an emissions test, that they emit less than 10 tpy HCl if they wish to claim area source status. The EPA is allowing three (3) test methods:
 | EPA Method 320 in Appendix A to 40 CFR Part 63; |
| EPA Method 321 in Appendix A to 40 CFR Part 63; |
| ASTM Method D 6735-01 (it is required that the paired-train option in Section 11.2.6 and the post-test analyte spike option in Section 11.2.7 be used). |
Compliance Date
| Compliance Date for Existing Sources – January 5, 2007 |
| Compliance Date for New Sources Constructed before January 5, 2004 is January 5, 2004 and all performance tests must be conducted by July 5, 2004. |
| Compliance Date for New Sources Constructed after January 5, 2004 is the initial date of start-up and all performance tests must be conducted no later than 180 days after start-up. |
Affected Sources
The affected sources include 1) lime kilns and its associated coolers; and 2) individual processed stone handling (PSH) systems. A PHS system includes all equipment beginning at the stone storage bin or open storage pile and ending where the processed stone is fed into the kiln. Emission units in a PHS system include conveying system transfer points, bulk loading or unloading systems, screening operations, bucket elevators and belt conveyors. No other material processing operations (MPO’s) are subject to this rule.
Emission Limitations
The primary air toxics found in kiln exhausts are hydrogen chloride and metals such as arsenic, cadmium, chromium, and nickel. The rule, however, only has numeric limits for particulate matter, as a surrogate for non-volatile and semi-volatile HAP metals. The emission limitations are:
Lime Kilns and their associated lime coolers
|
· Existing lime kilns and their associated lime coolers that did not have a wet scrubber installed and operated prior to January 5, 2004 - 0.12 pounds of particulate matter (PM)/ton of stone feed (lb/tsf); |
|
· Existing lime kilns and their associated lime coolers that have a wet scrubber that was installed and operating prior to January 5, 2004 – 0.60 lb/tsf of PM. If at any time after January 5, 2004 the kiln changes to a dry control system, then the PM emission limits is changed to 0.12 lb/tsf. |
|
· New lime kilns and their associated lime coolers - 0.10 lb/tsf of PM. |
|
· For both new and existing lime kilns and their associated coolers where owner chooses to average PM emissions (except that any kilns meeting 0.60 lb/tsf is ineligible for averaging) – weighted average PM emissions calculated according to Equation 2 in 63.7112 must not exceed 0.12 lb/tsf if averaging only existing kilns/coolers or 0.10 lb/tsf if averaging only new kilns/coolers. If averaging both existing and new kilns/coolers, emissions must not exceed weighted average calculated according to Equation 3 in 63.7112, except that no kilns and its associated cooler considered alone may exceed an average PM emission limit of 0.10 lb/tsf. |
Processed Stone Handling (PSH) Operations
|
· Stack emissions from all PSH operations at a new or existing affected source – 0.05 grams per dry standard cubic meters (g/dscm). |
|
· Stack emissions from all PSH operations at a new or existing affected source, unless the stack emissions are discharged through a wet scrubber control device – Emissions not to exceed 7% opacity. |
|
· Fugitive emissions from all PSH operations at a new or existing affected source, except if enclosed in a building – Emissions must not exceed 10% opacity. |
|
· All PSH operations at a new or existing affected source enclosed in a building – All individual affected PSH operations must comply with the PM and opacity limitations or the building must comply with the following: |
|
o No visible emissions from the building, except from a vent; |
|
o Vent emissions must not exceed 0.05 g/dscm of PM and 7% opacity. |
|
· For each fabric filter that controls emissions from only an individual, enclosed storage bin, the opacity emissions must not exceed 7%; |
|
· For each set of multiple storage bins with combined stacks emissions, emissions must not exceed 0.05 g/dscm of PM and 7% opacity. |
Operating Limits
Kilns and PSH operations using a wet scrubber to meet the emission limitations will be required to maintain the 3-hour block average gas stream pressure drop across the scrubber and 3-hour block average scrubber liquid flow rate at levels equal to or above the levels established during the performance test for PM.
Kilns using a fabric filter or ESP must monitor opacity using a continuous opacity monitoring system (COMS) and maintain the opacity level of the kiln at or below 15% for each 6-minute block period. As an alternative to the COMS, a PM detector can be used and must be maintained such that the alarm is not activated and the alarm condition does not exist for more than 5% of the operating time in each 6-month period. For kilns that use a fabric filter, a bag leak detection system (BLDS) can be used as an alternative to the COMS or PM detector. As with the PM detector, the BLDS alarm must be maintained such that the alarm is not activated and the alarm condition does not exist for more than 5% of the operating time in each 6-month period.
The owner or operator will have to prepare a written Operation, Maintenance and Monitoring (OM&M) Plan that details procedures for proper operation and maintenance of each emission unit and control system, procedures for monitoring and proper operation of monitoring equipment and corrective action to be taken when necessary.
Compliance Demonstrations
For the initial compliance demonstration, a performance test to demonstrate compliance with an emission and/or opacity limitation must be conducted by the dates detailed above in Compliance Dates. During the initial test, if using a wet scrubber, control device parameters must be monitored so that appropriate operating limits can be set for demonstration of continual compliance.
Continual compliance for kilns/coolers and PSH operations using a wet scrubber is demonstrated by maintaining the 3-hour block average of the exhaust gas stream pressure drop and scrubbing liquid flow rate greater than or equal to levels established during the performance test. Both parameters are to be continuously monitored.
Continual compliance for kilns/lime coolers equipped with a fabric filter using a bag leak detection system or equipped with a fabric filter or ESP and using a PM detector is demonstrated if the alarm is not activated and the alarm condition does not exist for more than 5% of the total operating time in each 6-month period. For kilns using a COMS, the owner is required to maintain each 6-minute block average opacity level at or below 15% opacity.
For continuous compliance with opacity and visible emission limits, monthly visible emission checks of each units will be required. If no visible emissions are observed for 6 consecutive monthly checks, the frequency can be decreased from monthly to semi-annually. If visible emissions are observed during any semi-annual check, the frequency must be resumed to monthly. If no visible emissions are observed during the semi-annual check, the frequency can be decreased to annual.
Author: Kimberly D. Coy, Senior Engineer
Date: January 5, 2004