Phoenix Process Engineering, Inc. Project Experience Helping Clients Achieve MACT Compliance

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1 Phoenix Process Engineering, Inc. Project Experience Helping Clients Achieve MACT Compliance The Boiler MACT, 40 CFR 63, Subpart DDDDD, was vacated in 2007 by the U.S Court of Appeals and the 2004 rule was remanded. For solid fuel fired existing boilers the vacated rule addressed emissions limits (PM, HCl, and Hg) and there were no continuous emissions monitoring (CEM) requirements. Small solid fuel fired boilers (10 million BTU s per hour or less) had emissions limits for PM only under this vacated rule. The EPA s promulgated schedule is to issue a proposed Boiler MACT rule for public comment in April, 2010 and promulgate a final rule in December, Phoenix Process Engineering, Inc., has 45 years experience in the application of bag houses, including the replacement of ESP s with bag houses. For elevated temperature gas streams we have extensive experience in gas cooling prior to treatment in bag houses and ESP s. This work includes the application of air atomized water sprays, spray towers, quench chambers, and process gas-to-air heat exchangers. Systems have been designed to cool gases from 750 F (and higher) to as low as 250 F using air atomized water spray systems. This work has included gas flow modeling and spray tower sizing to resolve uneven distribution in existing spray tower systems and define the configuration of the new facilities we designed. We have also designed air atomized water spray cooling systems for metallurgical applications in which off gas temperatures varied from 2200 F to 750 F. We are not implying water spray towers or systems are the only solution to elevated temperature gas streams, only that we have experience in these systems. Key project summaries are presented. Our expertise, experience and qualifications allow us to identify project efficiencies and savings. This ability to identify opportunities by looking outside the box is often lost at larger engineering companies. The majority of these summaries focus on bag house and ESP applications. We also have expertise in gas cleaning systems requiring scrubbers and in sulfur dioxide capture, abatement of oxides of nitrogen and the technical needs of the emerging technology of mercury capture. We would be pleased to present our more descriptive PowerPoint presentation of these projects and our qualifications, capabilities and expertise to you and your colleagues. Phoenix Process Engineering, Inc Cave Springs Road, Suite 305, St. Peters, Mo Phone: , Fax:

2 Reference Profile: The client requested engineering services for replacement of a collector duct at the discharge of cyclones and replacement of a gas duct to the bag house manifold. This duct was failing in place with numerous holes. Investigations determined the existing horizontal duct was in danger of failure from years of overload from accumulated dust, which enhanced corrosion and the occurrence of cyclone plugging. Replacement ducts were designed with adequate carrying velocities and installed, providing for a more uniform dust loading to the bag house and eliminating saltation. Total project value: NA

3 Reference 05101/05111 Profile: The client requested an evaluation and performance review of an existing fabric filter due to high filter bag failure rate. This fabric filter handled the off gas streams from two similar processes. Annual bag replacement costs rose from $250,000 to $500,000 in one year and significantly impacted operating up time. All system components were thoroughly inspected internally and externally. Upstream gas quality was assessed. These investigations showed the high bag failure rate was due to a series of events including wet dust coating the bags resulting in concentration of gas flow and cleaning air flow to a reduced cleaning area. This in turn resulted in dust penetrating the weave, higher differential pressure, more frequent cleaning and mechanical deterioration of the bags. The cause of the wet dust was determined to be an inadequately sized gas cooling tower aggravated by high water pressure spray nozzles that did not provide the needed fine water droplet size.

4 Phoenix received a subsequent assignment to design two properly sized gas cooling towers with the correct inlet cone geometry and atomizing nozzles that provide that Sauder Mean Diameter (SMD) water droplets. Although the fabric filter was not the main problem some low pressure transition ducts with straightening vanes were needed in certain elbows and some other inlet manifold modifications were made to get equal gas and dust distribution to each compartment, extending bag life. As the recommendations needed several months to implement interim solutions to reduce fabric filter failures were provided including a reconstituted water system, specific additional maintenance procedures and different spray nozzles. Total project value: $4.4 million. This was the lowest cost solution.

5 Reference Profile: The client planned to re-activate an alkali bypass of a four stage preheater kiln. Phoenix provided engineering services to support the client s purchase of major equipment. This included new quench air fans, a new fabric filter, a new inlet air damper for secondary cooling of bypass gases, and a new ID fan. Phoenix designed modifications to the existing quench chamber to improve performance. Vendor proposals were evaluated through a) generating comparative capital cost estimates inclusive of structural, mechanical and electrical costs, b) providing general conceptual arrangement drawings, c) evaluation of risk factors for each system including buildup of alkali chlorides, periodic removal of buildups and access and safety considerations for the work, and d) a capital cost summary of each option. Vendor submitted approval drawings were modified where needed. Additional project features included: A fresh air damper to control moisture in duct gases. A new duct from the quench chamber to the new bag house. A new bin vent filter for an existing dust storage bin. An ESP had to be removed to accommodate this system. In this case we were able to re-use the removed ESP s structural steel base for the new (smaller footprint) bag house. The existing ID fan s base was reused for the new ID fan with minimal modifications saving time and money. Total project value: ~$1.5 million

6 Reference Profile: The client requested we analyze the flue gas temperature profile and review the performance of the downstream fabric filter due to inadequate bag life. We provided a detailed analysis of the requested items and other items we identified as possible contributors to the high failure rate, including temperature control, bag cleaning cycle frequency, bag characteristics, particulate emissions, and system online time. Recommendations were implemented and bag failures were reduced. Total Project value: NA Reference 05107/05114 Profile: The client was faced with the need to rebuild an ESP. Due to emissions limits issues a bag house would be necessary on the clean side of the ESP in addition to rebuilding the ESP. The upstream process equipment was experiencing corrosion believed to be due to the presence of condensed acid gas in the gas stream. We suggested an alternative to rebuilding the ESP was to install a new fabric filter suitably protected against corrosion by coating the steel components. Mechanical, Process and Electrical Specifications were prepared for the supply and erection of the fabric filters and ID fan. Conceptual plans and Capital cost estimates were developed comparing two bag house vendors. Evaluations of the potential vendors capabilities and equipment were provided. An 800,000 acfm bag house at 425 F was needed. The performance guarantee for the bag house was emissions particulate concentration had to be less than gr/dscf and opacity had to be less than 10%. The ID fan was sized at 2500hp. Total project value: $12.9 million (included new upstream ductwork and insulation. Reference Profile: The client requested engineering services for replacement of a collector at the discharge of cyclones and replacement of a gas duct to the bag house manifold. This scope was similar to reference although for a different client. In addition to the items addressed in reference we determined other items contributed to inadequate bag life. This system required bleed in air regulated to control gas temperature to the bag house and the duct diameter was modified to provide gas velocities to minimize dust settling out. Total Project Value: NA

7 Reference Profile: The client requested a capital cost estimate and preliminary engineering for replacing an ESP with a bag house. Downtime for the switchover had to within the normal maintenance period of days. Project related items that could impact the work required during the switchover period included confirmation of existing gas flow rates, pressures and temperatures and evaluation of the existing gas cooling tower and ID fan to meet the new requirements. Rather than remove the existing ESP we determined it was more cost effective to leave it in place, using it as a combination duct and drop out chamber prior to the new bag house. The new fabric filter s location did not require the existing ESP to be removed. This arrangement helped meet the client s constraint of switchover time. Some modifications were made to the existing gas cooling tower to improve performance. Design requirements for the new bag house were 137,000 acfm at 475 F. Total project value: $4.1 million. Project completed on time and within budget and has been in operation for five years.

8 Reference 06130/07131 Profile: The client requested engineering services to replace an ESP with a bag house to comply with emissions limits at this Canadian facility. Phoenix proposed a two step process with a) preliminary engineering to define the layout, define the flow sheet and preparation of a capital cost estimate and b) the complete engineering services to allow a contractor to install the new bag house and demolish the existing ESP. The preliminary engineering phase examined two alternatives to capture the dust: Use the existing ESP as a drop out chamber. Install cyclones ahead of the bag house and demolish the existing ESP once the new system was on line. The scope of the detailed engineering depended on whether the ESP was left in place or demolished with cyclones installed. Our evaluation and capital cost comparisons indicated re-use of the ESP as a drop out chamber was a cost effective solution. We received a subsequent assignment to provide detailed engineering for this selection. The new bag house design capacity was 227,000 acfm at 450 F with a vendor performance guarantee that emissions would not exceed 0.01 gr/dscf to meet regulatory requirements. Total project value: $7.1 million.

9 Reference Profile: With the success of reference 06130/07131 this same client requested engineering services to replace an ESP with a bag house to comply with emissions limits on another piece of process equipment at this Canadian facility. Phoenix determined a bag house capacity of 450,000 acfm at 500 F was needed. Specifications were prepared and vendor quotes solicited with a performance guarantee for the emissions not to exceed 0.01 gr/dscf. A capital cost estimate was prepared for capital appropriation submittal. Unfortunately, funds were not approved for this $6.2 million project, which remains open to this day. Reference 07124/07136 Profile: The client requested a study to determine the needed process modifications to reduce emissions and improve carbon capture at an activated carbon production facility. Phoenix included evaluating the client s original proposal of adding cyclones, calculating expected operating parameters and providing recommendations regarding the advisability and expected results of the operation. Our evaluation indicated adding cyclones without additional process gas fans would introduce unacceptable pressure drops. An expanded project scope was required. We were awarded a subsequent assignment to develop the project and provide detailed engineering services. Besides reducing emissions an added scope of the expanded project was to develop additional heat recovery. Total project value: $4.5 million. Reference Profile: Due to the high cost of a carbon black material handling system from the vendor, Phoenix Process Engineering was asked to develop a more cost effective system. The process flow stream was Raw Material to Grinding to Bag House to Storage to Pelletized to Dryer to Bagging. Phoenix designed the material handling system and the process and nuisance dust collection systems. Total project value: $1.3 million. The client is currently considering our services for additional production facilities.

10 Reference Profile: The client requested we evaluate their air pollution control system on a proprietary drying process and define a system that will meet stipulated emissions limits. The original designed system did not adequately capture the process emissions and subsequent work by a second engineering company did not result in any further improvement at this Canadian facility. We provided flow diagrams of the recommended system with our report. Additional equipment (a bag house and additional fan) was needed to capture particulate emissions. System gas carrying velocities were excessive and resulted in mechanical damage that can be avoided. We developed a schedule where the system modifications could be made without disrupting production and downtime of less than two days would be needed for the final connections. Total project value: In progress. Total project cost estimated to be less than $0.5 million.