1

MEMORANDUM

DATE: August 2 9

, 201 4

SUBJECT: Revised Technology Review for the Ferroalloys Production Source Category

FROM: Bradley Nelson, EC/R, Inc.

TO: Phil Mulrine , EPA OAQPS/SPPD/ M IC G

1.0 PURPOSE

The purpose of this memorandum is to summarize the re visions to the technology review to identify developments in practices, processes, and control technologies for emissions sources of hazardous air pollutants (HAP) from the ferroalloys production source category. This analysis is part of
EPA’s review efforts in accordance with section 11 2(d)(6) of the Clean Air Act (CAA). The technology review 1 was re

- evaluated using information received after proposal of the amendments to the national emission standards for hazardous air pollutants (NESHAP) for the ferroalloys production source category published in the Federal Register on November 23, 2011 (76 FR 72508).

2.0 BACKGROUND

Under the CAA section 112, EPA must establish technology

- based standards for sources of HAP. These technology

- based standards are often referred to as maximum achievable control technology, or MACT, standards. Section 112 also contains provisions requiring EPA to periodically revi ew these standards. Specifically, paragraph 112(d)(6) states:

(6) REVIEW AND REVISION.

– The Administrator shall review, and revise a s necessary (taking into account developments in practices, processes, and control technologies), emissions standards promulgated under this section no less often than every 8 years.

The current National Emissions Standards for Hazardous Air Pollutants (NESHAP) for Ferroalloys Production: Ferromanganese and Silicomanganese w as promulgated on May 20, 1999 (64 FR 27450) and codified at 40 CFR part 63, subpart XXX. The 1999 NESHAP (40 CFR 63.1650(a)) applies to all new and existing ferroalloys production facilities that manufacture ferromanganese or silicomanganese and are major sources or are co

- located at major sources of HAP emissions. The rule’s product

- specific applicability reflected the only known major source at the time of

1 Memorandum from Beth Friedman, Jeff Harris, and Brad Nelson, EC/R to Conrad Chin, US EPA, OAQPS, Draft Technology Review for the Ferroalloys Production Source Category, October 27, 2011.2

promulgation. Today, there are two ferroalloys production facilities subject to the MACT rule. No new manganese ferroalloys production facilities have been built in over 20 years, and no new ferroalloys production facilities are anticipated in the fores eeable future.

Ferroalloys are alloys of iron in which one or more chemical elements (such as chromium, manganese, and silicon) are added into molten metal. Ferroalloys are consumed primarily in iron and steel making and are used to produce steel and ca st iron products with enhanced or special properties. Emissions of HAP are generated from electrometallurgical (furnace) operations (primary and tapping), other furnace room operations (ladle treatment and casting), raw material handling and product handli ng , and are primarily emitted from ferroalloys production as process emissions
and process fugitive emissions . There is also potential for some outdoor fugitive dust emissions.

Process emissions are the exhaust gases from the control devices, primarily from the furnace, metal oxygen refining , local ventilation, and crushing operations. The HAP process emissions are primarily composed of metals (mostly manganese, ars enic, nickel, lead, mercury and chromium) and also include organic compounds (such as PAH s) that result from incomplete combustion of coal or coke that is charged to the furnaces as a reducing agent. There are also process metal HAP emissions from the product crushing control devices. Process fugitive emissions occur at various points during the smelting process (such as during charging and tapping of furnaces and casting) and are assumed to be similar in composition to the process emissions. Outdoor fugitive dust
emissions are believed to be minimal due to required fugitive dust control mea sures in the 1999 MACT rule. Nevertheless, some fugitive dust HAP emissions can result due to material handling, vehicle traffic, wind erosion from storage piles, and other various activities.

The MACT rule applies to process and process fugitive emissi ons from the submerged arc furnaces, the metal oxygen refining process, and the product crushing equipment and outdoor fugitive dust
emissions sources. For process sources, the NESHAP specifies numerical emissions limits for particulate matter (as a surro gate for non

- mercury metal HAP) from the electric (submerged) arc furnaces, depending on furnace type, size, and product being made. Particulate matter emission limits (again as a surrogate for non

- mercury metal HAP) exist for the metal oxygen refining pro cess and product crushing and screening equipment. Table 2

- 1 provides a summary of the applicable
limits.3 Table 2

- 1

. E missions Standards in the Ferroalloys NESHAP

(40 CFR part 63, subpart XXX)

New or Reconstructed or Existing Source Affected Source Applicable PM Emission Standards

New or reconstructed Submerged arc furnace 0.23 kg/hr/MW (0.51 lb/hr/MW)

or 35 mg/dscm (0.015 gr/dscf)

Existing Open submerged arc furnace producing

ferromanganese and operating at a furnace power input of 22 megawatts (MW) or less 9.8 kg/hr (21.7 lb/hr)

Existing Open submerged arc furnace producing

ferromanganese and operating at a furnace power input greater than 22
MW 13.5 kg/hr (29.8 lb/hr)

Existing Open submerged arc furnace producing

silicomanganese and operating at a furnace power input greater than 25
MW 16.3 kg/hr (35.9 lb/hr)

Existing Open submerged arc furnace producing

silicomanganese and operating at a furnace power input of 25 MW or less 12.3 kg/hr (27.2 lb/hr)

Existing Semi

- sealed submer ged arc furnace

(primary, tapping, and vent stacks) producing ferromanganese 11.2 kg/hr (24.7 lb/hr)

New, reconstructed, or existing Metal oxygen refining process 69 mg/dscm (0.03 gr/dscf)

New or reconstructed Individual equipment associated with

the product crushing and screening operation 50 mg/dscm (0.022 gr/dscf)

Existing Individual equipment associated with

the product crushing and screening operation 69 mg/dscm (0.03 gr/dscf)4

The 1999 NESHAP established a building opacity limit of 20 percent that is measured during the required furnace control device performance test. The rule provides an excursion limit of 60 percent opacity for one 6

- minute period during the performance test

. The opacity observation is focused only on emissions exiting the shop due solely to operations of any affected submerged arc furnace. In addition, blowing taps, poling and oxygen lancing of the tap hole; burndowns associated with electrode measurements; and maintenance activities associated with submerged arc furnaces and casting operations are exempt from the opacity standards. For outdoor fugitive dust sources, the 1999 NESHAP requires that plants operate according to an outdoor fugitive dust control plan
that describes in detail the measures that will be put in place to control outdoor fugitive dust emissions from the individual outdoor fugitive dust sources at the facility.

3 .0 RE

- EVALUATION OF THE PROPOSED RULE AMENDMENTS BASED ON
DEVELOPMENTS IN PRACTICES, PROCESSES AND CONTROL
TECHNOLOGIES

The propos ed rule amendments to the NESHAP for the ferroalloys production source category published in the Federal Register on November 23, 2011 (76 FR 72508) included changes to the stack emission limits and requirements for the capture of fugitive emissions. The proposed rule included changes to the stack emission limit for PM (as surrogate for metal HAP ) , in addition to the
inclusion of HAP emission limits for mercury, formaldehyde, p olycyclic a romatic h ydrocarbons (PAH) and hydrogen chloride (HCl). The 2011 proposed amendments also included a proposed requirement for a furnace building ventilation system, which encloses the building and evacuates the captu red emissions to a control device. These proposed amendments in 2011 for PM were based on the initial technology review of the ferroalloys industry. The limits for Hg, PAHs, formaldehyde and HCl were proposed under 112(d)(2) and (d)(3) of the Act. A sum mary of the proposed emission limit requirements in the 2011 proposal publication is provided in Table 3

- 1.

The proposed furnace stack emission PM limits were a result of a technology review of test data
received from the 2010 Information Collection Reque st ( ICR ) . Since the proposed rule was published, EPA has received additional test reports from the facilities, including test data in response to a 2012 ICR. Based on these new test data, the emission limits proposed in the
NESHAP amendments were re

- eval uated. Because PM limits (as a surrogate for metal HAP) are already established in the current NESHAP for Ferroalloys Production, a technology review was performed for the proposed rule. The technology review for the 2011 proposed rule found that develop ments in practices, processes, and control technologies had occurred and therefore, EPA proposed tighter revised PM emission limits as shown in T able 3

- 1. These proposed limits were significantly more stringent than the limits in the 1999 MACT rule as they reflected the current performance of the facilities, and for some of the limits, presented in a different format (i.e., mg/dscm, instead of kg/hr).5

Table 3

- 1. Proposed HAP Emission Standards for the Ferroalloys Production NESHAP that

were publ ished in the November 2011 Proposal ( 76 FR 72508)

HAP Pollutant New or

Reconstructed or Existing Source Affected Source Proposed Emission Standard

PM (surrogate for metal HAP) New or reconstructed Electric arc furnace 9.3 mg/dscm corrected to 2% CO 2

PM (surrogate for metal HAP) Existing Electric arc furnace 24 mg/dscm corrected to 2% CO 2

Hg New, reconstructed, or existing Electric arc furnace 16 μg/dscm corrected to 2% CO 2

PAH New, reconstructed, or existing Electric arc furnace 89 μg/dscm corrected to 2% CO 2

HCl New, reconstructed, or existing Electric arc furnace 809 μg/dscm corrected to 2% CO 2

Formaldehyde New, reconstructed, or existing Electric arc furnace 201 μg/dscm corrected to 2% CO 2

PM (surrogate for metal HAP) New, reconstructed, or exis ting Local ventilation used to capture tapping, casting, or ladle treatment emissions 24 mg/dscm corrected to 2% CO 2

PM (surrogate for metal HAP) New, reconstructed, or existing MOR process 3.9 mg/dscm corrected to 2% CO 2 PM (surrogate for metal HAP) New, reconstructed, or existing MOR process 13 mg/dscm corrected to 2% CO 26

The technology review for this rule was re

- evaluated to include the additional test data received
after the 2011 proposed rule was published. The results of this revised technology review for PM (a surrogate for metal HAP) are presented in this memorandum. The results of the PAH and HCl analyses can be found in the revised MACT floor memorandum. 2 The mercury emission limit was

re

- evaluated and presented in the mercury co ntrol option memorandum. 3 The formaldehyde
emission limits were not change d as the new data continued to support the 2011 proposed emission limit for formaldehyde.

3.1 PM Furnace Stack Emission Limit

Under Section 112(d)(6) of the CAA, EPA is required to revi ew the emission standards, taking into account developments in practices, processes, and control technologies , and revise the standards if appropriate based on that review

. As shown in Table 2

- 1, the PM limits, used as a surrogate for metal HAP, in the existing NESHAP for the furnaces ranged from 21.7 to 35.9 pounds per hour (lbs/hr) depending on the furnace size, type and product being produced. For the 2011 proposed rule, t he particulate matter (PM) emissions that were reported by the industry in t he 2010 ICR were far below the level specified in the 1999 NESHAP, indicating improvements in the control of PM emissions since promulgation of the existing NESHAP. In 2011, based on the initial technology review, EPA proposed revised emissions limits for PM, which are shown in Table 3

- 1 . These limits
were based on limited data from the facilities and did not include test data from each furnace. In addition, the 2011 proposed rule revision for the PM furnace limits included a correction for the exhaust gas carbon dioxide (CO 2 ) concentration.

Prior to the supplemental proposal, EPA received multiple test data from each of the furnaces at the

two facilities

. Under the revised technology review

, the emissions and performance of each of the
furnaces in the sou rce category were again evaluated and compared with the emission limits in the
1999 MACT rule. Th e new test data received from the ferroalloy production facilities in response to information requests from EPA for this NESHAP review show outlet PM emission rates from the furnaces ranging from 0.5 to 12.9 lbs/hr. Based on th is evaluation , it was again determined that all
of the furnaces had PM emissions well below the PM limits in the 1999 MACT rule. Because all of furnaces were performing well below the 1999 MACT limit, the potential to establish a lower PM limit for furnaces under the technology review was evaluated to reflect the current performance of the furnaces and reduce “allowable” PM emissions for the source category without being so stringent as to require facilities to replace their current PM control devices. To determine an appropriate level for a PM limit that would reflect the improved performance of furnaces since the 1999 MACT rule, the PM emissions data from the highest emitting furnace ( Eram et F urnace 12)

w ere evaluated to determine a potential PM limit for the supplemental proposal. Another factor considered in selecting the revised proposed PM limit for furnaces is the expectation that Eramet

2 Memorandum from Bradley Nelson, EC/R to Phil Mulrine , EPA OAQPS/SP PD/M IC G, Revised MACT Floor Analysis for the Ferroalloys Production Source Category, August 2 9 , 201 4

. 3 Memorandum from Bradley Nelson, EC/R to Phil Mulrine , EPA OAQPS/SPPD/M IC G, Mercury Control Options and Impacts for the Ferroalloys Production Industry, August 29, 2014

.7

will likely need to upgrade the existing scrubbe r on Furnace #12 in order to comply with the proposed requirements for process fugitive emissions and as described in Eramet’s particulate control plan

. 4 A summary of the test results and average test data concentrations for each of the furnaces is provided in Appendix A. The test data for Eramet Furnace #12 includes five 3

- run tests
and the average of the se five PM test data points was calculated to be 16.9 milligrams per dry
standard cubi c meter (mg/dscm) with minimum and maximum test averages of 9.9 and 23.8 mg/dscm, respectively. Based on th ese data and the expecta t ions that Eramet will likely need to upgrade the controls on that furnace to meet the standards for process fugitive emissi ons , we conclude that all existing furnaces should be able to maintain PM emissions below 25 mg/dscm without the need to completely replace their control devices and therefore the EPA is propos ing an emission limit of 25 mg/dscm for existing ferroalloy pro duction furnaces in the 2014 supplemental proposal based on the revised technology review

.

The proposed revised new source PM limit was determined by evaluating the test data from the best performing furnace from the test data provided to EPA. The average furnace PM outlet
concentrations were calculated and ranked for each of the furnaces

. A summary of the data set used for determining the best performing furnace is provided in Appendix A. Based on this ranking,
Furnace 2 at Felman was selected as the best performing furnace . The test data for Furnace 2
includes fo ur 3

- run tests with an average of 1.67 mg/dscm and minimum and maximum test

average s of 0.79 and 2.51 mg/dscm, respectively. With regard to all the 12 individual test runs, we
observe that th e highest measured value of all 12 runs was 3.73 mg/dscm. Based on these data and analyses, and given that the highest test result from Furnace #2 is 3.73 mg/dscm, we conclude that a new source with a similar or better baghouse will be able to meet a PM em issions limit of 4 .0

. Therefore, b ased on this revised technology review , the EPA is propos ing an emission limit of 4 .0 mg/dscm for new ferroalloy production furnaces.

A test report w as received from Eramet recently that included March 2014 PM test res ults from the Furnace 12 scrubber outlet, Furnace 1 baghouse outlet, and the Furnace 1 tapping baghouse outlet. However, th ese data w ere not included in this analysis because a quality assurance assessment could not be performed before the finalization of this memorandum. The test report is available in
the docket and will be analyzed during the comment period for the supplemental proposal. Potential comments on this test report are requested in the Federal Register notice for this supplemental proposal

.

4 “Estimated Costs For Potential Fugitive Particulate Control Modifications at Eramet Marietta Inc. (as of 11/22/2013)”, Eramet Marietta Inc, 11/22/13. “Answers for EPA”, Felman Production Inc, 11/12/13.8

3.3 PM Local Ventilation Stack Emission Limit

The 1999 MACT rule did not include any PM emission limits for local ventilation control devices
associated with the furnace (e.g., units that control tapping, casting or ladle treatment emissions)

. Only one of the facilities operates a separate baghouse to control emissions from tapping operations at the furnace (Eramet Furnace 1 Tapping Baghouse). An e mission limit for PM from this emission

source w as included in the 2011 proposed rule, but was based on the PM emission limit from the furnace outlet. Since the proposed rule was published, EPA has received three PM test reports that
include PM emissions test results (with 9 test runs) from the tapping baghouse . Since EPA never
established a MACT Floor limit for the local ventilation stacks, a standard UPL analysis 5 was conducted using the 3 emissions tests results (9 test runs) to calculate a 99% UPL. The calculated 99% UPL is 3.94 mg/dscm. Based on this UPL analysis, EPA is proposing a PM emissions limit of

4 .0 mg/dscm for local ventilation stacks in the supplemental proposal

. A summary of the data set
and the UPL calculation for the local ventilation unit is provided in A ppendix A.

Because the data set only included test data from one source, the “best performing source” was determined to be the Eramet Furnace 1 Tapping Baghouse and t herefore, the revised PM MACT limit for both new and existing sources for local ventilation devices was determined to be 4 .0 mg/dscm.

3.4 PM Metal Oxygen Refining Stack Emission Limit

No additional test data was received after the publication of the proposed rule for the metal oxygen refining (MOR) operation

. Therefore, the proposed limit of 3.9 mg/dscm that was presented in the 2011 proposed rule would still be appropriate for new and existing metal oxygen refining operation

sources based on the technology review

. 6

3.5 Crushing and Sizing Stack Emission Limit

The technology review for the 2011 proposed rule calculated a proposed stack emission limit of 13 mg/dscm for crushing and screening equipment that would apply to both new and existing sources. No additional test data was received after publication of the proposed rule and therefore the proposed limit wa s not revised.

5 Memorandum from Phil Mulrine, EPA OAQPS to Docket ID No. EPA

- HQ

- OAR

- 2010

- 0895, Use of the Upper Prediction Limit for Calculating MACT Floors, July 30, 2014.

6 Memorandum from Beth Friedman, Jeff Harris, and Brad Nelson, EC/R to Conrad Chin, US EPA, OAQPS, Draft Technology Review for the Ferroalloys Production Source Category, October 27, 2011.9

3. 6 Metal HAP Fugitive Emissions

The technology review for the proposed rule evaluated an option to enclose the furnace building(s)
and evacuate the fugitive emissions of metal HAP to a control device(s). The determination was based on the feasibility of install ing enclosures and hav ing the fugitive emissions at the ridge vents of the shop building collected under negative pressure and ducted to a control device, with a PM
emissions limit at the control de vice stack outlet set at the same level as for the furnace stacks. This would allow sources the option to duct some or all process fugitive emissions to an existing furnace control device if it has excess capacity.

After proposal, EPA received cost estima tes from the two ferroalloy production facilities that show that the proposal cost estimates of building evacuation were underestimated. The cost estimates algorithms used for the proposed rule building evacuation costs were based on the EPA Control
Cost Manual

. 7 The facilities provided vendor quotes and engineering designs that estimated the cost of building ventilation 2

- 3 times higher than the EPA estimate. W e have reviewed this information and agree that the costs and feasibility of building enclosur e in the 2011 proposal were underestimated

. Therefore, the technology review for controlling fugitive metal HAP emissions

was re

- evaluated to determine if other control methods could be used.

Both ferroalloys production facilities submitted alternat ive c ontrol methodolog ies for controlling

process fugitive HAP emissions from the furnace buildings based on the principle of enhanced capture options

. 8

, 9 These enhanced capture options methods included;

 Increasing primary capture at the source of fugitive metal HAP emissions,

 Adding primary capture to sources that were previously uncontrolled,

 Adding secondary capture to capture fugitive metal HAP emissions not captured by the primary capture system,

 Partitioning of parts of the building where fugitive metal HAP emissions occur, and

 Installing new metal HAP control devices to control the captured fugitive emissions.

The EPA has evaluated these design narratives from the facilities and believes that they provide comparable fugitive metal HAP reductions a s the building evacuation option. In addition, the total cost of installing and operating this enhanced capture option is considerably less than the building evacuation option. A comparison of the fugitive emission capture options is provided in the cost impacts memorandum for ferroalloys production. 10

7 EPA Air Pollution Control Cost Manual

– Sixth Edition, http://www.epa.gov/ttncatc1/products.html

8 QSEM, National Emissions Standards for Hazardous Air Pollutants: Ferroalloys Production Technical Comments to Alternative Approach to NESHAP Subpart XXX Compliance

- November 23, 2011 Proposed Rule, June 29, 2012

. 9 Chu & Gassman Design Narrative, July 9, 2012

. 10 Memorandum from Jeff Harris and Brad Nelson, EC/R to Phil Mulrine , US EPA, OAQPS, Cost Impacts of the Controls Options considered for the NESHAP for the Ferroalloys Production Source Category to Address Fugitive HAP Emissions

, August 1 3 , 201 4

.10

3.7 Outdoor Fugitive Dust Emissions

Outdoor fugitive emissions are believed to be relatively low. Nevertheless, t he technology review for the proposed amendments to the Ferroalloys Production NESHAP was unable to quantify HAP
emissions from these sources and did not identify any additional procedures or controls that could be expected to have a significant impact on these emissions. The determination in the technology review for controlling outdoor fugi tive emissions i s that the e xisting requirements for an outdoor fugitive dust control plan still reflect an appropriate control approach for those potential emissions

sources

. No additional data was received for this fugitive emission source, and therefor e the requirement of the outdoor fugitive dust control plan that is in the 1999 MACT rule was determined

to still be the best control option for this source.

4.0 CONCLUSIONS

Th e re

- evaluation of the technology review did not identif y any new developments in practices, processes, or control technologies that have been implemented in this source category since the proposed rule was published. However, new test data indicates that both facilities have significantly reduced stack emissions of met al HAP compared to allowable levels, primarily through improved performance of baghouses.

Based on the re

- evaluation of the technology r eview, it was conclude d that it is feasible and cost

effective for facilities to achieve an existing source furnace st ack PM emissions limit of 2 5 mg/dscm and new source furnace stack emissions limit of 4 .0 mg/dscm. The re

- evaluation also determined that new and existing local ventilation control devices could achieve a PM emission
limit of 4 .0 mg/dscm. The previous tec hnology review concluded that a stack PM emission limit of 13 mg/dscm for new and existing crushing and screening equipment is reasonable. Our analyses
indicate that a stack emission limit for PM of 3.9 mg/dscm is achievable for new and existing metal

oxyg en refining operations.

We believe that these controls and measures are cost

- effective and reflect achievable performance for this industry. Details of the costs and emissions reductions associated with these measures are
available in the cost impacts mem orandum available in the docket for the Ferroalloys Production
source category.11 Appendix A

Furnace and Local Ventilation PM Data Sets1213