Report of Northwest Portland ESCO Corporation: Conditions 59 and 60 of Title V Permit No , Reduction of Emissions from Dump Back Process

Transcription

1 Report of Northwest Portland ESCO Corporation: Conditions 59 and 60 of Title V Permit No , Reduction of Emissions from Dump Back Process July 24, 2012 Jim Karas P.E. Fred Tanaka James Karas

2 Table of Contents Executive Summary... 3 Objective... 4 Background... 4 Tasks and Schedule... 5 Summary of Observations... 6 Estimate of Emission Reductions... 6 Recommendations... 7 Conclusion... 7 Appendix... 8 Attachment 1: Attendees at June 28 & 29 visit... 8 Attachment 2: Glossary... 9

3 We were tasked to assess the improvements to reduce emissions at the dump back process at the Main Plant and Plant 3. The dump back is a step in the foundry process. It occurs after metal is melted in the electric arc furnaces (EAF), where alloy ingredients are added and this molten metal is poured into a transfer ladle. It is then moved to a station where final trim ingredients are added, and molten metal is dumped back and forth for a thorough mixing. This step was identified as one that generates significant emissions of both PM and metallic hazardous air pollutants (HAPs) in the 11/12/2010 ERM report 1 and the 6/16/2011 Karas Report 2. Recommendations were made to capture and control these emissions. Rather than directly capturing and controlling emissions generated during this process, ESCO chose to change their production process with the eventual goal of eliminating the dump back procedure for a majority of alloys they produce. To reduce the need for this step, alloy materials are added directly at the EAFs and during tapping where emissions are directly controlled. This project involved observing several transfers of molten metal at the EAFs into ladles until they were moved to the pouring area. During runs with dump back operations, ESCO operators performed dump back operations to simulate the process. During runs of no dump back, after tapping, the molten metal was moved directly to the mold pouring area, eliminating dump back operations altogether. At the Main Plant, the emission reductions from this change are estimated at 2 tons of particulate matter (PM) per year. At Plant 3, the PM emission reductions are estimated at 1 ton per year. 1 Final Air Emissions Assessment and Alternatives Analysis ESCO Corporation Steel Foundry Operations, Thomas W. Rarick, P.E., Environmental Resources Management, Carmel, Indiana, November 12, Final Report of Independent Review of Northwest Portland ESCO Corporation Alternatives Analysis, DEQ Contract #048-11, June P a g e

4 In June 2012, we were hired by ESCO to perform qualitative visual observations of metal transfers from the EAFs to the pouring area at the Main Plant and Plant 3. In the past, these events included a step called dump back, which was identified as generating significant PM and metallic HAP emissions. We observed simulations of events when dump back was performed and events when there was no dump back. This change represents Attachment A, Items 11 and 12 of the Good Neighbor Agreement (November 22, 2011) and is required in Conditions 59 and 60 of ESCO s Title V Permit No The commitments in Attachment A state that ESCO will Identify and implement operating changes to reduce emissions at the dump back and transfer points. The objective of this report is to provide an assessment if emission reductions have been achieved and to estimate the degree of those reductions. Founded in 1913, ESCO Corporation operates two steel foundry/metals casting facilities in Northwest Portland, Oregon. Their Main Plant is located at 2141 NW 25th Avenue. Plant 3 is located at 2211 NW Brewer and has operated since These plants manufacture parts for the construction, mining, and timber industries. The Main Plant fabricates larger metal products based on job orders whereas Plant 3 creates smaller products, primarily less than 40 pounds, and their operation is virtually continuous. This report focuses on the dump back process of ESCO s operation. After steel is melted in the EAFs (both plants) and refined in the (AOD) Argon Oxygen Decarburization (Main Plant only), the molten steel is transferred to different ladles before it is poured into the molds for casting. In the past for most heats, the melted metal was transferred into a transport ladle to a dump back station to adjust the metallurgy of the steel, heat the pouring ladle spout and to manage temperature of the melt. When dump back was used metal was transferred between the transport ladle to a smaller dump back ladle during which material such as alloys were added to produce a specific product. Empty paper bags, containing the needed material, were thrown into the small ladle to get the correct composition. When molten metal is moved back and forth between ladles during the dump back process or when the slag is displaced, significant air emissions are generated that are visible inside the melt shops. After the dump back process is completed, the transport ladle is conveyed to pouring ladles for pouring metal into molds. ESCO s Air Permit (Title V Operating Permit No ) Conditions 59 and 60 require that ESCO identify and implement operating changes to reduce emissions at dump back and transfer points at the Portland Main Plant and Plant 3 facilities. ESCO decided to change procedures and reduce the use of the dump back process from most of their production. ESCO believes that it can reduce the dump back process at the Main Plant for most of their steel alloys or about 70% of their production. At Plant 3, ESCO believes they can eliminate over 90% of the dump back process for all of their alloys. 4 P a g e

5 The Title V permit requires that ESCO use a consultant to conduct qualitative visual observations before and after the operating changes are complete. The goal of the visual observations is to determine if emissions have been reduced as a result of the changes. ESCO evaluated alloys that could eliminate dump back mixing operations. The practice of eliminating dump back operations began in April, At Plant 3, they started with one shift and by June after a number of refinements, practices, and training all shifts were converted and this became the standard practice. During June, over 90% of all Plant 3 heats were processed without using the dump back operation. At the Main Plant, all alloys made for pouring at the Doghouse are targeted to use this new operation. In addition, chain making, which is typically done once per week, is also targeted to use the new process. During June, about 70% of Main Plant heats were processed without using the dump back operation. The 2011 Karas report recommended controls such as portable bag houses to reduce emissions at the dump back process. Instead, ESCO chose to target eventual elimination of the dump back process on most alloys. Changing a production process is a significant effort. ESCO believes they can achieve the emission reductions while maintaining product quality. Quality issues can take time to reveal themselves. All products should be tracked over time to insure that indeed quality has not been sacrificed. The major tasks covered by this contract are: Observe several events where molten metal is tapped and taken to the pouring area. Both simulated dump back and no dump back events were observed. Submit draft report of the independent assessment, including an estimate of the emission reductions. Submit final report. June 28, 2012 Met with ESCO representatives for introductions and project overview. Visited Main Plant and Plant 3 for observations. Community representatives were present for most of the day. June 29, 2012 Visited Plant 3 for observations. Met with ESCO representatives for a closing meeting and next steps. July12, 2012 Submitted draft report to ESCO. July 25, 2012 Submitted final report to ESCO. 5 P a g e

6 Nine (9) events were observed at the Main Plant and Plant 3. The following table summarizes each event. # Date & Time 1 5:35 2 7:21 3 8:55 4 9: : : :03 8 7:31 9 8:59 Location Alloy Dump Back? Comments MP 12SL No Some emissions when temperature was taken. MP 12C Yes Emissions observed during transfer between ladles, break up slag & taking of temperature. MP 12C No Some emissions when temperature was taken. MP 12C No Some emissions when temperature was taken. MP 12C Yes Emissions observed during transfer between ladles, break up slag & taking of temperature. P3 N/A No No significant emissions observed. The wait at DB station to pouring area was 5 minutes. P3 N/A Yes Emissions observed during dump back and when the bag was added. P3 N/A No No significant emissions observed. P3 N/A Yes Emissions observed during dump back and when the bag was added. The emissions observed in 2011 were much more significant from the dump back operations than what was observed in June The simulated operation did not include adding any ingredients at the dump back operation. At the Main Plant, no additional trim material was added to simulate dump back, but at Plant 3, operators intentionally undershot the required alloy ingredients, so that trim material could be added during dump back. At Plant 3, the side arm control system is in place during melting and the Cupola vent is closed. After tapping, the side arm control system is returned to the idle position and the Cupola vent is opened. Wind drafts can reduce the emissions captured. During our visit, the wind draft was not a factor and the control system was efficient. The Cupola vent is presently the secondary capture and control system for operations that now take place at the EAF instead of the dump back. From their 2011Emissions Inventory to the Oregon Department of Environmental Quality of Northwest Portland (DEQ), the dump back process used an emission factor of P a g e

7 pounds of PM emissions per ton of metal melted. This attributed 2.96 tons of PM emissions in 2011, using 30,350 tons of metal melted. In the Main Plant, 70% of the metal melted is targeted to eliminate the dump back step. By conservatively assuming that 70% of the dump back activity will be eliminated the resulting emission reduction at the Main Plant is estimated to be 2 tons of PM emissions. Emission reductions at Plant 3 are more difficult to estimate because the emissions of the dump back activity are not separated. They are included in the emission factor for the EAF and these emissions are partially captured by the Cupola vent. All these emissions are now occurring at the EAF which are controlled. In 2011, fugitive PM emissions from Plant 3 were estimated at 6.57 tons using 20,230 tons of metal melted. Assuming direct controls will improve overall capture efficiency by an additional 1%, from 95% to 96%, the emission reduction of PM emissions is estimated at 1 ton per year. ESCO should track all melts for dump back use for each alloy. In addition, ESCO should track products to ensure quality has not been sacrificed due to the new process. Decreasing the need for the dump back process is a major step to reducing PM emissions from the manufacturing sites. At the Main Plant, the dump back process has no emission controls. Plant 3 dump back emissions are somewhat controlled when the furnace Cupola vent is open. By reducing the need for the dump back process, potential PM emissions that would have been lost are now captured at the furnace, resulting in a net improvement or reduction in emissions. By reducing the need for dump back operations for many alloys, ESCO has significantly reduced emissions. Since the implementation of this new process ESCO has eliminated the need for dump back at Plant 3 by about 90%. At the Main Plant, about 70% of the production has been initially targeted with this new process. Assuming the same production rate as in 2011, emission reduction of PM emissions for both plants is estimated at 3 tons per year. Since the implementation of this process change is only a few months old, more time will allow ESCO to refine and improve the new processing practice. 7 P a g e

8 Attachment 1: Attendees at June 28 & 29 visit June 28, 2012 Pete Betich, Plant 3 Maintenance Manager Kelley Egre, ESCO Director Public Affairs and Communications Jay Fagan, Plant 3 Site Manager Sharon Genasci, Neighborhood Advisory Committee, NW District Association Tom Giese, Neighborhood Advisory Committee, Neighbors for Clean Air Bob Holmstrom, Neighbor, NW District Association James Karas, consultant Jim Karas, consultant Aaron Koeher, Main Plant Site Manger Brian Krytenberg, ESCO, Global Environmental Process Engineer Fred Tanaka, consultant Robert Van Riper, Plant 3 Manufacturing Manager J. Carter Webb, ESCO, Manager, Environmental Affairs Allen Wedderburn, GM Portland Plants June 29, 2012 Jay Fagan, Plant 3 Site Manager James Karas, consultant Jim Karas, consultant Aaron Koeher, Main Plant Site Manager Brian Krytenberg, ESCO, Global Environmental Process Engineer Fred Tanaka, consultant Robert Van Riper, Plant 3 Manufacturing Manager J. Carter Webb, ESCO, Manager, Environmental Affairs 8 P a g e

9 Attachment 2: Glossary AOD Argon oxygen decarburization DEQ Oregon Department of Environmental Quality of Northwest Portland Dump back A process where metal is mixed by transferring it back and forth between ladles. Additives are usually incorporated during dump back step when used. EAF Electric arc furnace HAP Hazardous air pollutant MP Main Plant N/A Not available P3 Plant 3 PM Particulate matter Particulate matter emissions that are 2.5 microns or less PM P a g e