### DATE: November 12 , 2014

SUBJECT: Supplemental Proposal Technical Support Document for the Secondary Aluminum Production Source Category

FROM: Mark Bahner , RTI International

TO: Rochelle Boyd

, U.S. E nvironmental P rotection A gency (the EPA)

The purpose of this memorandum is to document the technical approach and rationale used to develop certain proposed modifications to the National Emission Standards for Hazardous Air Pollutant s (NESHAP) for Secondary Aluminum Production ( 40 CFR Part 63, S ubpart RRR ). The Supplemental Proposal is scheduled for signature in November 2014 , and will likely be published in the Federal Register a few weeks later

.
1. Capture Efficiency Assumption for Uncontrolled Furnaces Test data related to the capture efficiency for uncontrolled furnaces were analyzed. Two tests were available. Both were conducted at Southwire Corporation in Hawesville, KY. Testing was performed for PM, HCl and PCDD/PCDF from April 30

– May 02, 2007 at Furnace #5 in Mill 3, and reported on June 26, 2007. Testing was performed for PM, HCl and PCDD/PCDF from July 17

– 19, 2007 at a Group 1 furnace located in Rod Mill 1 and reported on September 5, 2007. These tests were performed on a furnace stack and also on a temporary canopy hood, which was installed for the test, to capture emissions not directed through the furnace stack.

One aspect of this testing , regarding sampling time at the canopy hoods versus the furnace stacks, potentially affects the results

. In the testing reported on June 26, 2007, sampling at the furnace stack was performed from 7.7 to 8 hours per run, whereas sampling at the canopy hood was performed for 3.0 to 3.33 hours per run. This is consistent with the concept th at emissions captured by the canopy hood would only occur during furnace charging, whereas emissions through the furnace stack would occur throughout the cycle (charging, melting, tapping) which presumably lasted 7.7 to 8.0 hours. However, in the testing r eported on September 5, 2007, testing at the furnace stack was performed for 3.2 hours per run, whereas testing at the canopy hood was performed for 3.0 hours per run. This could mean that the complete furnace cycle was only 0.2 hours longer than the charg ing period, or it could be a mistake in the testing reported on September 5, 2007, such that the testing at the furnace stack did not occur throughout the entire furnace cycle. If the testing reported on September 5th was indeed flawed in that the sampling at the furnace stack did not occur throughout the furnace cycle, then the ratio of emissions from the canopy hood to total emissions (canopy plus furnace stack emissions) would be biased high.

The results of the two tests are summarized in Table 1

. From Table 1, it can be seen that the average capture by the furnace stack, for all pollu tants and for both tests, was 71 percent. The EPA has considered various potential furnace stack capture eff i encies and resultant stack test estimation factors for unc ontrolled furnaces. For example, if the furnace capture efficiency is assumed to be 50 percent, the furnace test results would need to be mul tiplied by a factor of 2 to calculate total emissions . If the furnace capture efficiency was assumed to be 66.67 pe rcent (approximately 67 percent), the furnace test

### results would need to be multiplied by a factor of 1.5 to calculate total emissions . The test results in Table 1 support multiplying the furnace test results by a factor of 1.5, because the average captur e efficiency for all tests was 71 percent, which is slightly higher than 67 percent

. Additional tables related to this analysis are included in Appendix A to this memorandum. The tables can be summarized as follows:

Table A1 : This table presents data from the June 26, 2007 report. The data included pollutant emissions in pounds per hour and test sampling time. These are converted into total mass measured, so that the total emissions from the furnace stack can be compared
to t he total emissions in the canopy hood stack. For example, the during Run 3, hydrogen chloride (HCl) emissions in the furnace stack were 5.31 pounds (lb), and 0.84 lb in the canopy hood, for a total of 6.15 lb.

Table A2 : This table presents data from the Ju ne 26, 2007 report. The data are exclusively in pounds and the table includes a calculation of the percentage of pollutants emitted through the canopy hood stack versus the total mass of pollutants emitted through both the canopy hood stack and the furnace stack. For example, the 3

- run average fraction for HCl in the canopy hood is 0.19, meaning that 19 percent of the HCl passes through the canopy hood.

Table A3 : This table presents data from the September 5 , 2007 report. The data included pollutant emissio ns in pounds per hour and test sampling time. These are converted into total mass measured, so that the total emissions from the furnace stack can be compared to the total emissions in the canopy hood stack. For example, the during Run 3, hydrogen chloride (HCl) emissions in the furnace stack were 2.18 pounds (lb), and 0.84 lb in the canopy hood, for a total of 3.02 lb.

Table A4 : This table presents data from the September 5 , 2007 report. The data are exclusively in pounds and the table includes a calculati on of the percentage of pollutants emitted through the canopy hood stack versus the total mass of pollutants emitted through both the canopy hood stack and the furnace stack. For example, the 3

- run average fraction for HCl in the canopy hood is 0.23, meani ng that 23 percent of the HCl passes through the canopy hood.

2. Costs for Lowering the Dioxin/Furan (D/F) Emissions L imit for Group 1 Furnaces To evaluate the potential to reduce D/F emissions, our analysis focused on two options: 1) lower the D/F emissions limit from 15 to 10 μ g TEQ/Mg for group 1 furnaces processing other than clean charge at all facilities ; and 2) lower the D/F emissions limit for Group 1 furnaces processing other than clean charge to 10 μ g TEQ/Mg, after applying a subcategorization that only required facilities with a Group 1 furnace production capacity of more than 200,000 tons per year (tpy) to meet the lower limit. The lower limit could potentially be met with activated carbon injection systems.

With regard to the first option, base d on testing reported in information collection request responses 1



### , and supplemental information received from facilities after the 2012 Proposal 2 

### , there are twelve Group 1 furnaces with emissions above 10 μ g/Mg as shown in Table 2 . All twelve furnaces are presently controlled with fabric filters, and it is assumed that activated carbon injection would be added. The total capital cost for adding activated carbon injection on the 12 furnaces is estimated to be $390,000, and the total annualized cost is estim ated to be $1,400,000 (see Table 3 ) . The total annual D/F emission reduction s if all furnaces emitted at 10 μ g/Mg are estimated to be approximately 0.49 grams TEQ.

2

### Therefore, the calculated cost effectiveness is approximately $2,900,000 per gram TEQ of D/F (see Table 4 )

. For the second option, only facilities with combined production capacity of all Group 1 furnaces greater than 200,000 tpy would be required to meet the 10 μ g TEQ/Mg limit. Of the facilities listed in Table 2

, Aleris Recycling (RTI #389) a nd Novelis Corporation (RTI #269) have a production capacity greater than 200,000 tpy. The calculated total capital cost to add carbon injection to the three furnaces at RTI #389 and the one furnace at RTI #269 is estimated to be $130,000, and the total an nualized cost is estimated to be $46 0 ,000 (see Table 3 ) . The total emission reduction s if these four furnaces emitted at the 10 μ g TEQ/Mg limit would be 0. 12 grams TEQ. Therefore, the calculated cost effectiveness is approximately $3,800,000 per gram TEQ of D/F (see Table 4 )

.

3. Compliance with Emission Limits during Startup/Shutdown

The EPA is proposing standards for startup and shutdown for all secondary aluminum process units. The subpart RRR standards would apply at all times, including periods of s tartup and shutdown. Because the scrap processed at secondary aluminum production facilities is the source of emissions, emissions during startup and shutdown are expected to be no higher and probably much lower than emissions during normal operations sinc e no scrap would be processed.

For production processes in the secondary aluminum production source category where the standards are expressed in units of pounds per ton of feed or similar units (i.e. thermal chip dyers, scrap dryer/delacquering kiln/dec oating kilns , dross

- only furnaces, in

- line fluxers using reactive flux and group 1 furnaces), the form of the standard would raise implementation issues if facilities were simply required to demonstrate compliance in the exact same way as they do during no rmal operations because the equipment is not receiving feed material during startup and shutdown periods . For example, the startup procedure for a furnace consists of gradually heating the furnace to normal operating temperature, without any addition of fe ed material. Since the feed rate is zero, the emission rate per ton of feed would be calculated to be infinite.

One possibility would be to have concentration

- based limits. However, these are probably not appropriate for the secondary aluminum industry, because hooding draws in large amounts of ambient air in order to increase hooding capture. Therefore, i t is expected that emissions during startup and shutdown could be measured and determined under the applicable test method in pounds per hour (lb/hr). U nder the 2012 proposed rule, to demonstrate compliance during the startup and shutdown periods, for the emissions standards that are in units of lbs per ton, t he emissions in units of pounds per hour w ould be divided by the feed rate in tons per hour (ton/ hr) from the most recent or current performance test and compared to the emission limit for the affected source . For example, the PM limit for a new or existing group 1 furnace is 0.4 lb/ton. If, during a startup or shutdown, the emission rate determined u nder the applicable test method is 2 lb/hr, and the furnace charge rate during the most recent performance te st was 10 tons per hour, the calculated emission rate for that test during a period of startup or shutdown would be 0.2 lb/ton of feed (2 lb/hr of PM divided by 10 tons per hour of feed). This would be in compliance with the PM standard of 0.4 lb/ton of feed.

4. Representativeness for Nine

- Company HAP Metals and HAP Organics Testing

The EPA use d a n ine

- company ICR t o gather testing data that would correlate emissions of THC surrogate to speciated organic HAP s and emissions of PM surrogate to speciated metal HAPs . Testing was limited to nine companies for efficiency and to avoid undue burden to the industry. The nine

3

### companies were chosen primarily beca use they were large companies operating many facilities, and because the se companies are known to operate major source facilities that ha ve thermal chip dryers or scrap dryer/delacquering/decoating kilns. Thermal chip dryers and scrap dryer/delacquering de coating kilns are the only types of equipment that have THC limits. Testing for t hese two pieces of equipment were limiting, in that few companies in the secondary aluminum source category currently operate those pieces of equipment. Therefore, the sampling of th e pieces of equipment was quite representative, because the sampling represented a large fraction of th e equipment operated by the industry. The sampling for HAP metals in fabric filter dust r epresented a much smaller fraction of the industry (less than 10 percent of all equipment). However, there were a total of 55 samples analyzed for the full suite of HAP metals (including arsenic, cadmium, total chromium and hexavalent chromium, manganese, mercury, nickel, etc.)

. Because 55 samples were taken from many facilities owned by nine companies, these results are believed to be representative of metal concentrations in fabric filter dust within the secondary aluminum industry and are suitable for u se in developing speciated metal HAP emissions from PM emissions.

References

References

1. Letter, Peter Tsirigotis (U.S. EPA) to Russell Mayfield (Mayfield Salvage Company) et al.,

“ Requirement to provide information according to 42 U.S.C 7414 ,” February 7, 2011. This was the cover letter for the all

- company data collection ICR.

2. Memorandum, Mark Bahner (RTI, International) to Rochelle Boyd (U.S. EPA), “Development of the RTR Supplemental Proposal Risk Modeling Dataset for the Secondary Aluminum Production So urce Category,” July 11, 2014. This memorandum also has a table that correlates RTI facility ID numbers wi th facility names and locations.

4

## List of Tables

Table 1. Southwire Test Results Summary

................................ ................................ ................................ . 6 Table 2. Group 1 Furnaces with Reported Emissions Greater than 10 μg TEQ/Mg Feed

......................... 6 Table 3. Group 1 Furnace D/F Reduction Options

................................ ................................ ..................... 7 Table 4. Cost

- effectiveness Calculation for D/F Reduction Options

................................ ......................... 7

Table A1. Southwire Testing Reported June 26, 2007: Complete Test Results

................................ ........ 9 Table A2. Southwire Testing Reported on June 26, 2007: Results in Pounds

................................ ........ 10 Table A3. Southwire Testing Reported September 5, 2007: Complete Test Results

.............................. 11 Ta ble A4. Southwire Testing Reported on September 5, 2007: Results in Pounds

................................ . 12

5

### Table 1

. Southwire Test Results Summary

Test Report Date Pollutant Three

- run Average Fraction in Furnace Stack Three

- run Average Fraction in Canopy Hood Stack
June 26, 2007 PM 0.78 0.22
June 26, 2007 HCl 0.81 0.19
June 26, 2007 D/F 0.97 0.03 Sept. 5, 2007 PM 0.49 0.51 Sept. 5, 2007 HCl 0.77 0.23 Sept. 5, 2007 D/F 0.42 0.58 Average for all All 0.71 0.29



### Table 2 . Group 1 Furnaces with Reported Emissions Greater than 10 μ g TEQ/Mg Feed

RTI ID Number Facility Name Emission Release
Point ID 2014 Reported
Emissions Update TEQ

(ug/Mg) 2014 Actual Emissions,

grams 2014
Emissions at

10 ug/Mg,

grams Emission Reduction at

10 ug/Mg,

grams 316 Metal Industries, Inc. 001 14.98 0.110 0.073 0.037
364 Continental Aluminum RV-1 14.55 0.224 0.154 0.070
269 Novelis Corporation 760MT 13.10 0.376 0.287 0.089
347 Hydro Aluminum - Louisville MELTFURN 01 (01) 12.40 1.055 0.851 0.204
389 Aleris Recycling P905 12.20 0.113 0.093 0.020
389 Aleris Recycling P901 11.30 0.105 0.093 0.012
302 Tennessee Aluminum Processors, Inc. 2 10.79 0.217 0.201 0.016
303 Aleris Specifiation Alloys, Inc. EP-002 10.77 0.350 0.325 0.025
392 Aleris Recycling, Inc. Rotary Furnace 7 10.50 0.351 0.334 0.017
364 Continental Aluminum RV-2 10.27 0.002 0.002 0.000
389 Aleris Recycling P903 10.20 0.095 0.093 0.002
303 Aleris Specifiation Alloys, Inc. EP-001 10.08 0.327 0.325 0.003
3.324 2.830 0.494 Totals



### 6

### Table 3

. Group 1 Furnace D/F Reduction Options

Option Furnace Status Number of Furnaces Capital Cost 1 Each (2011 $) Total Annual ized Cost Each

(2011 $) Combined Total Capital Cost (2011$) Combined Total Annualized Cost (2011$) Limit of 10 μg/Mg TEQ for all Controlled 1 2 32,478 115,983 390,000 1,400,000 Limit of 10 μg/Mg TEQ for all Uncontrolled 0 617,000 156,100
Limit of 10 μg/Mg TEQ if production >200,000 tpy Controlled 4 32,478 115,983 130,000 460,000 Limit of 10 μg/Mg TEQ if production >200,000 tpy Uncontrolled 0 617,000 156,100

1 

### Controlled furnaces have fabric filters, and are assumed to add activated carbon injection. Uncontrolled furnaces are assumed to add fabric filters with activated carbon injection.

Table 4

. Cost

- effectiveness Calculation for D/F Reduction Options

Option Combined Total Annualized Cost (2011$) Annual D/F Emission Reduction (grams TEQ) D/F Removal Cost Effectiveness ($/gram TEQ)
Limit of 10 μg/Mg TEQ for all 1,400,000 0.49 2,900,000
Limit of 10 μg/Mg TEQ if production >200,000 tpy 460,000 0.12 3,800,000



### 7

### Appendix A

Southwire Test Results

8

### Table A 1. Southwire Testing Reported June 26, 2007: Complete Test Results

* reported as 2378

- TCDD equivalent Southwire Testing Reported on June 26, 2007
PM PM HCl HCl TOTAL D/F* TOTAL D/F* Duration(hr) furnace stack
Run 1 7.70 0.56 #/hr 4.31 lb 0.71 #/hr 5.47 lb 8.69E-08 #/hr 6.69E-07 lb
Run 2 8.00 0.75 6.00 lb 0.7 5.60 lb 7.72E-08 #/hr 6.18E-07 lb
Run 3 7.70 0.57 4.39 lb 0.69 5.31 lb 2.18E-08 #/hr 1.68E-07 lb

Duration(hr) canopy hood
Run 1 3.00 0.32 #/hr 0.96 lb 0.51 #/hr 1.53 lb 3.87E-09 #/hr 1.16E-08 lb
Run 2 3.33 0.58 1.93 lb 0.41 1.37 lb 4.92E-09 #/hr 1.64E-08 lb
Run 3 3.00 0.41 1.23 lb 0.28 0.84 lb 2.95E-09 #/hr 8.85E-09 lb

Total
Run 1 5.27 lb 7.00 lb 6.81E-07 lb
Run 2 7.93 lb 6.97 lb 6.34E-07 lb
Run 3 5.62 lb 6.15 lb 1.77E-07 lb

average 6.27 lb 6.71 lb 4.97E-07 lb



### 9

### Table A 2. Southwire Testing Reported on June 26, 2007: Results in Pounds
Southwire Testing Reported on June 26, 2007

Pollutant Location Units Run 1 Run 2 Run 3 Average
PM Furnace stack lb 4.31 6.00 4.39 4.90
PM Canopy hood lb 0.96 1.93 1.23 1.37

PM Total lb 5.27 7.93 5.62 6.27

PM Furnace stack fraction of total 0.82 0.76 0.78 0.78
PM Canopy hood fraction of total 0.18 0.24 0.22 0.22 22% Avg
PM Total fraction of total 1.00 1.00 1.00 1.00

HCl Furnace stack lb 5.47 5.60 5.31 5.46
HCl Canopy hood lb 1.53 1.37 0.84 1.25
HCl Total lb 7.00 6.97 6.15 6.71

HCl Furnace stack fraction of total 0.78 0.80 0.86 0.81
HCl Canopy hood fraction of total 0.22 0.20 0.14 0.19 19% Avg

HCl Total fraction of total 1.00 1.00 1.00 1.00

Total D/F Furnace stack lb 6.69E-07 6.18E-07 1.68E-07 6.35E-07
Total D/F Canopy hood lb 1.16E-08 1.64E-08 8.85E-09 1.48E-08
Total D/F Total lb 6.81E-07 6.34E-07 1.77E-07 4.97E-07

Total D/F Furnace stack fraction of total 0.98 0.97 0.95 0.97
Total D/F Canopy hood fraction of total 0.02 0.03 0.05 0.03 3% Avg
Total D/F Total fraction of total 1.00 1.00 1.00 1.00



### 10

### Table A 3

. Southwire Testing Reported September 5, 2007 : Complete Test Results

Southwire Testing Reported on September 5, 2007

PM PM HCl HCl TOTAL D/F* TOTAL D/F* Duration(hr) furnace stack
Run 1 3.20 0.61 #/hr 1.95 lb 1.38 #/hr 4.42 lb 2.02E-09 #/hr 6.46E-09 lb
Run 2 3.20 0.49 1.57 lb 0.81 2.59 lb 3.97E-09 #/hr 1.27E-08 lb
Run 3 3.20 0.49 1.57 lb 0.68 2.18 lb 8.31E-10 #/hr 2.66E-09 lb

Duration(hr) canopy hood
Run 1 3.00 0.86 #/hr 2.58 lb 0.38 #/hr 1.14 lb 8.31E-09 #/hr 2.49E-08 lb
Run 2 3.00 0.36 1.08 lb 0.25 0.75 lb 2.20E-09 #/hr 6.60E-09 lb
Run 3 3.00 0.53 1.59 lb 0.28 0.84 lb 1.35E-09 #/hr 4.05E-09 lb

Total
Run 1 4.53 lb 5.56 lb 3.14E-08 lb
Run 2 2.65 lb 3.34 lb 1.93E-08 lb
Run 3 3.16 lb 3.02 lb 6.71E-09 lb

average 3.45 lb 3.97 lb 1.91E-08 lb



### 11

### Table A 4

. Southwire Testing Reported on September 5 , 2007: Results in Pounds
Southwire Testing Reported on September 5, 2007

Pollutant Location Units Run 1 Run 2 Run 3 Average
PM Furnace stack lb 1.95 1.57 1.57 1.70
PM Canopy hood lb 2.58 1.08 1.59 1.75

PM Total lb 4.53 2.65 3.16 3.45

PM Furnace stack fraction of total 0.43 0.59 0.50 0.49
PM Canopy hood fraction of total 0.57 0.41 0.50 0.51 51% Avg
PM Total fraction of total 1.00 1.00 1.00 1.00

HCl Furnace stack lb 4.42 2.59 2.18 3.06 HCl Canopy hood lb 1.14 0.75 0.84 0.91 HCl Total lb 5.56 3.34 3.02 3.97

HCl Furnace stack fraction of total 0.79 0.78 0.72 0.77 HCl Canopy hood fraction of total 0.21 0.22 0.28 0.23 23% Avg

HCl Total fraction of total 1.00 1.00 1.00 1.00

Total D/F Furnace stack lb 6.46E-09 1.27E-08 2.66E-09 1.06E-08 Total D/F Canopy hood lb 2.49E-08 6.60E-09 4.05E-09 1.27E-08 Total D/F Total lb 3.14E-08 1.93E-08 6.71E-09 1.91E-08

Total D/F Furnace stack fraction of total 0.21 0.66 0.40 0.42 Total D/F Canopy hood fraction of total 0.79 0.34 0.60 0.58 58% Avg Total D/F Total fraction of total 1.00 1.00 1.00 1.00



### 12