With over 80 Selective Catalytic Reduction (SCR) systems (33,100 MW) installed world wide and some 20 years accumulated experience, Alstom is a leading provider of SCR solutions that meet our customer’s most stringent NOx emission requirements. NOx is formed in all combustion processes incorporating air through a reaction between nitrogen and oxygen at elevated temperatures. Because NOx contributes to the formation of acid rain and photochemical oxidants, its emission levels have drawn the attention of regulatory authorities worldwide. Consequently, in the past 20 years, the allowable level of NOx emissions from combustion processes has continually diminished.  To read more click download.

Alstom has recently developed a novel, low-cost, pump-free absorber for limestone gypsum applications. By removing most of the moving parts and using gravity flow extensively, the Flowpac™ design provides high reliability, excellent performance, and low maintenance.  To read more click download.

From June 6th through September 4th, 2007, a Bio-Reaction Industries pilot unit was operated to demonstrate the control of the air emissions from the manufacture of phenolformaldehyde based products. The unit consisted of a biotrickling filter followed by a biofilter containing compost-packed, plastic ball media. A slipstream from the product dryer exhaust was directed to the biofilter via a temporary, spiral metal duct.  To read more click download.

This paper describes a wind tunnel modeling study conducted for the Mirant Potomac River Generating Station (MPRGS) located in Alexandria, Virginia. The study was commissioned because a screening-level model indicated potential for plume impacts at a nearby uniquely shaped high-rise building within a few hundred meters of the station, constructed long after the station started operation in 1949. Due to the complex interaction between the two buildings, both a computer dispersion modeling study using AERMOD and a wind-tunnel modeling study were undertaken to help answer questions about potential impacts. The wind-tunnel study was conducted to obtain a better understanding of the concentration spatial distribution on and around the high-rise building and to provide site-specific building dimension inputs (i.e., Equivalent Building Dimensions or EBD) for AERMOD, to account for the complex building interactions in a form that AERMOD could handle. The study also had the important goal to help MPRGS design modifications to the plant that would help reduce potential ambient impacts on the highrise building and other areas in the vicinity of the plant.  To read more click download.

Emissions Management Strategies - Emissions management for single plant is dependent on the complexity of the CO2 calculations and the emissions caps imposed by the governmental or the local state regulator. Different European countries have imposed contrasting data quality constraints.  E.g. In the Netherlands spreadsheet cannot be used for data processing but for most other countries verifiers and regulations have been less stringent.  To read more click download.

A new stack with Flue Gas Desulphurization (FGD) is being designed to replace an existing stack at the Reliant Energy Cheswick Generating Station (CGS) located in the Allegheny River valley, 15 miles northeast of Pittsburgh. Since the terrain to the south of the new stack rises 178 m above stack base, there was concern that terrain wakes may affect ground-level concentrations. Since AERMOD can currently only model building wake effects, a wind tunnel modeling study was conducted to determine the appropriate building dimension inputs (i.e., Equivalent Building Dimensions or EBD) for modeling upwind terrain wake effects with AERMOD. Even though this modeling is not currently required by EPA, CGS wanted to ensure that concentration levels due to terrain wake effects would not pose a problem after the stack was constructed.  To read more click download.

Corrosion and eventual leakage in heat exchangers can have several undesirable effects. A concentrated process stream may leak into cooling water that is discharged into a lake or river, causing pollution. Process water, used to condense steam to feed a large boiler, may leak into the condensate and severely damage the boiler. In non-critical applications, corrosion is a problem because a corroded heat exchanger is less efficient and energy is wasted.  To read more click view or download.

Wind tunnel modeling is a very useful tool to assess and mitigate odors from industrial, laboratory, sewage treatment, hospital, and landfill pollutant sources. As the EPA Fluid Modeling Guideline so aptly puts it: “A well-designed and carefully executed fluid modeling study will yield valid and useful information – information that can be applied to real environmental problems – with just as much and generally more credibility than any current mathematical models.” This paper discusses the validity of wind tunnel modeling and how these studies are conducted, and also presents three applications to assess and mitigate odor impacts.  To read more click download.

The Plywood and Composite Wood Panel MACT requires mills to control greater than 90% of HAPs emissions coming from the dryers and presses at plywood, MDF, particleboard, hardboard and OSB mills by September 2007. The EPA approved technologies are Thermal Oxidizers (TO) and Biofilters. Due to the increase in natural gas costs, the wood products industry has been very interested in determining if a biofilter has the ability to degrade HAPs to a level that will meet the MACT and secondarily, if a biofilter can degrade the pinenes, terpenes and other hydrocarbons to a level that would allow biofilters to be a viable alternative for controlling VOC emissions.  Too read more click download.

By replacing the sodium sulfide chemistry used in its nitrogen oxide (NOx) scrubber with a non-hazardous NOx control chemistry, ChemResearch Co. Inc. (CRC; Phoenix, AZ.) reduced its operating costs and eliminated a health and safety hazard.  To read more click download.

Siemens Power Generation combustion technology has under-gone a significant transformation over the past 20 years. Evolving from the 1980's diffusion flame combustor technology, whicproduces a very stable flame, but is associated with relatively higher levels of emissions output of some constituents, SiemensPower Generation incorporated material and technological design advancements, industry-leading design engineers, and state ofthe art design tools to develop a successful Dry Low NOx (DLNcombustion system in the 1990's.  To read more click download. 

When International Ingredient Corp.’s drying plant in Monroe,WI, opened in 1994, it was the first plant designed specifically for large-scale drum drying of dairy products for the feed industry.At that time, its only neighbor was a cheese producer. International Ingredient used a land spread technique to process the discarded liquids resulting from its neighbor’s cheese manufacturing process.  To read more click download.

At the Air and Waste Management Associations (A&WMA) meeting on April 2-3, 2008, in Washington DC, the Environmental Protection Agency (EPA) expressed the need for harmonization between whatever carbon reduction policy is adopted by the United States with existing pollution emission regulations under the Clean Air Act (CAA). The goal of this harmonization is to allow industry to reduce greenhouse gas emissions and improve air quality without causing a new layer of compliance requirements that are in direct conflict with existing regulation.  To read more click download.

The thermal mass flow meter’s ability to deliver a direct reading of mass flow rates of air, natural gas and other fuel gases provides a simple, reliable and cost-effective method for tracking and reporting fuel consumption.  To read more click download.

The Roseville Energy Park (REP) will be a natural gas-fired, combined-cycle electrical generating facility. The project,planned for a 12-acre site, will be owned by the city.and will use state-ofthe-art equipment to locally generate about 60 percent of Roseville’s electricity needs. The Roseville Energy Park will use recycled wastewater from the nearby Pleasant Grove Wastewater Treatment Plant as its source of cooling water during operation. A zero liquid discharge (ZLD) system will be used to recover process wastewater and generate sludge for offsites disposal.  To read more click view or download.

Federal efforts, along with federal transportation funding aimed at reducing the health risks from air pollution, have started to make a difference, but must be protected and strengthened if the nation’s initial progress is to be sustained. Even so, some in Congress and the Bush Administration are proposing to make drastic changes to clean air laws and programs that could severely undermine current and future progress towards cleaner air. These changes could seriously jeopardize ongoing efforts to protect public health from air pollution. This report:  To read more click view or download.

The Babcock & Wilcox Company (B&W) has developed a rule driven design (RDD) computer application to speed the design of its wet flue gas desulfurization (WFGD) slurry spray header system including support steel. The application, written using the RuleStream RDD system, captures the talents of the many people involved in the spray system.s design, including those involved in process engineering, design engineering technology, structural mechanics, and technical design. B&W's design standards and best practices are blended with fabricator capabilities and industry standards to form the application rules. Third-party software (for example CAESAR II) and proprietary computer programs are leveraged by the application courtesy of the RuleStream RDD architecture.  The application seeks to automate the routine first 80% of the design, while providing interfaces to complete the design or explore what-if situations. Interfaces allow the evaluation of spray coverage, pipe velocities, pressure drop, physical clearances, weights, and stresses. The application generates drawings, a solid model, and a bill of material for fabrication. Using the application, repeatable, consistent results are achieved. There is a higher confidence in the generated design and a reduction in design cycle time. This saved time may be allocated to exploring alternative designs, pursuing fabricator quotes, performing contract level analysis in the proposal phase, or may be applied to other areas of the WFGD design.  To read more click download.

New Brunswick Power (NB Power) is the largest electric utility in Atlantic Canada with a generating capacity of more than 4000 MWe consisting of nuclear, thermal, and hydro. Among the generation portfolio, Coleson Cove generating station with its 1050 MWe generating capacity is NB Power’s largest generation facility. In 2002, NB Power embarked on a multi-facet emissions reduction and plant improvement program:  To read more click download.

When a high-sulfur fuel is fired in a combustor, the sulfur in the fuel combines with oxygen and forms gaseous sulfur dioxide (SO2).  SO2 can further be oxidized into sulfur trioxide (SO3). After the air heater, the reduced temperature changes some SO3 to acid mist that can corrode flues, air heaters, and other equipment. SO3 forms an aerosol in a wet scrubber, which contributes to a visible, trailing plume. A wet flue gas desulfurization/scrubber (WFGD) system collects some acid mist. Acid mist can be considered PM2.5 and may become regulated. There can be more acid mist than dry particulate in many wet scrubber stacks. Control of acid mist may be required for permits in the future. Wet electrostatic precipitators (WESPs) can be successfully applied to address fine particulate emission requirements from fossil-fuel-fired combustors.  To read more click download.

Levels of outdoor air ventilation required to meet Federal and State building codes add substantially to the cooling load of buildings located in hot, humid climates.  The largest part of this increased load is the latent (moisture removal) load of the moist outdoor air.  To read more click download

Total particulate emissions are being set near detection limits on new or revised power plant operating permits. Acid gas emissions, such as SO3, which form particulate and make up a portion of total particulate, must be controlled to even lower values. Thus, the selected acid gas control technologies must be based on meeting the required emissions. This paper provides the results of investigations that have been performed and demonstrates achievable SO3 emissions utilizing an emissions control system approach for a range of fuel sulfur contents. Available total particulate emission results on both high and low sulfur fuels with multiple control technologies are presented as demonstration of SO3 mitigation. Consideration of multiple SO3 mitigation technologies and reagents is included. The conclusions of this analysis can be utilized in the economic selection of the proper control technologies for the selected primary fuel and sulfur content to achieve the total particulate emissions.  To read more click download.

A new, staged low-NOx, pulverized coal burner named AireJet™ was developed with the aid of computational fluid mechanics modeling and tested at pilot scale. Tests were conducted in a 100 million Btu/hr facility that was set up with “separated” and “close-coupled” overfire air (OFA) ports at different elevations above the burner centerline. An eastern high-volatile bituminous Middle Kittanning coal and a western Powder River Basin Black Thunder coal were chosen for testing. Effects of burner hardware, combustion stoichiometry, and coal fineness on NOx (NO + NO2), CO, and loss of ignition (LOI) were evaluated. Under the normal operating conditions of 17% excess air and 0.85 burner stoichiometry, and with the OFA ports being separated about 21 ft above the burner centerline, we achieved 0.148 lb NOx/MBtu and 3.84% LOI for the eastern bituminous Middle Kittanning coal and 0.076 lb NOx/MBtu and 0.35% LOI for the western Black Thunder coal, respectively. In the close-coupled OFA arrangement, the OFA ports were 2 and 3 ft above the burner centerline, resulting in 0.240 lb NOx/MBtu and 1.26% LOI for the Middle Kittanning coal, versus 0.122 lb NOx/MBtu and 0.34% LOI for the Black Thunder coal. In the first commercial application of twelve AireJet burners in a 95 MWe utility boiler that burns a Powder River Basin coal, the NOx emissions averaged around 0.13 lb/MBtu and the LOI levels were less than 1%.  To read more click download.

To comply with Title I guidelines from the Clean Air Act Amendments of 1990, coal-fired power plants in the United States were required to have significant reductions in their nitrogen oxides (NOx) emissions by May 1, 2003. Many utilities have or are already planning the installation of Selective Catalytic Reduction (SCR) systems on operating units to meet these and future requirements.  Consumers Energy approached The Babcock & Wilcox Company (B&W) to engineer, fabricate and install Selective Catalytic Reduction (SCR) equipment at the Dan E. Karn generating facility, located in Essexville, Michigan. Karn 1 is a 255 MW CE tangential fired boiler; Karn 2 is a 260 MW B&W wall-fired boiler (Fig. 1).  After extensive evaluation of reagent suppliers, Consumers Energy contracted with Chemithon Corporation for their SafeDeNOx® process to convert urea to ammonia.  To read more click download.

Recent upgrades to the AES Deepwater Unit have been completed to reduce NOx, SO3 and fine particulate emissions. The changes made on the system to achieve this reduction and the testing completed in 2007 and 2008 to confirm these reductions are outlined in this report. A comparison of similarities and differences between the AES Deepwater installation and a typical high sulfur coal-fired plant is also discussed. The series of tests conducted were across the SCR and air heater for SO3, across one of the recently upgraded wet ESPs measuring SO3 and Total PM, and in the stack for SO3 and Total PM. The results of the tests and descriptions of the test methods are presented.  To read more click download. 

This paper describes the successful design, installation and operation of Canada.s first Selective Catalytic Reduction (SCR) systems for nitrogen oxides (NOx) reduction installed at Ontario Power Generation.s (OPG.s) Lambton and Nanticoke coal fired power stations. OPG.s initiative to reduce the emissions of NOx (which contribute to the formation of smog) from their coal fired stations led to the award of a contract to Babcock & Wilcox Canada (BWC) in June 2001 for the turnkey supply of SCRs for Lambton units 3 & 4 and Nanticoke units 7 & 8. B&W.s scope included design, supply, construction and start-up of the SCRs, anhydrous ammonia systems, SCR support steel, pressure part modifications, platework modifications and reinforcement, control components and induced draft (ID) fan upgrades.  To read more click download.

CycloneTM boiler owners continue to drive down NOx emissions by increasingly sophisticated staging and air distribution schemes. For example, Alliant Energy has employed RMT’s SmartBurn® technology, and Ameren UE has pioneered neural nets to reduce emissions. Over the last 11 years under sponsorship of EPRI, the team of ORNL and B&W has developed pulverized coal burner diagnostic technology by applying nonlinear signal analysis techniques to flame scanner signals. The team has extended the technology to cyclones to facilitate deeper staging of the cyclones to reduce NOx emissions. Development projects were conducted at the Alliant Energy Edgewater Units 3 and 4, and Ameren UE Sioux Unit 1. Nonlinear analysis statistics were correlated to upsets in cyclone operation resulting from poor air distribution in the burner and barrel. The team demonstrated that the lighter and main flame scanners can be used to independently guide adjustments to the burner and barrel.  To read more click download.

The authors will present a paper detailing key test data on the individual and cumulative roles of SCR catalyst, ammonia injection, and sodium hydrosulfide (NaHS) on the speciation and removal of mercury within a forced-oxidized limestone scrubber. Testing was completed at Dominion Resources 1,662-megawatt Mount Storm power station (firing a medium sulfur Eastern bituminous coal) in Grant County, West Virginia.  Baseline mercury removal testing was completed under several scenarios including full flue-gas bypass of the SCR (with one full ozone season of operation or approximately 3300 hours) and fluegas flow through the SCR with and without ammonia injection.  After baseline testing, sodium hydrosulfide was injected into the scrubber recirculation pumps to evaluate its impact on oxidation and re-emission of elemental mercury. Ontario Hydro sampling occurred at the economizer exit, air heater exit, wet scrubber inlet, and wet scrubber outlet with a set of solid/liquid samples (coal, ESP ash, FGD slurry, FGD gypsum, FGD purge water) taken during each sampling period.  Results indicated the effectiveness of B&W’s patented injection technology (sodium hydrosulfide) in suppressing the re-emission of elemental mercury. Moreover, the presence of SCR catalyst significantly impacted the mercury speciation profile at the inlet of the wet scrubber, causing oxidation of the remaining elemental mercury.  The oxidized mercury was effectively removed by the wet scrubber.  To read more click download.

Michigan South Central Power Agency (MSCPA) operates a nominal 55 MW unit with a limestone forced oxidized WFGD system. It has been in operation since 1983. The absorber was a tray tower with a single tray designed for 90% SO2 removal and supplied by The Babcock & Wilcox Company (B&W). The boiler fires high sulfur eastern bituminous coal producing SO2 loadings up to 7.5 lbs/MBtu. To increase the removal in the WFGD system, MSCPA and B&W added a second tray in 2002 to take advantage of dual tray technology. SO2 removal has been increased from 90% to 98% without the use of organic acids. Performance tests and parametric tests have been performed on the system over the last two years. The testing also included tests for SO3, HF, HCl, and PM. This paper discusses the absorber design, operating parameters, results of the testing and system chemistry.  To read more click download.

Wet electrostatic precipitators (WESPs) have been commercially available since their first introduction by F.G. Cottrell in 1907. However, most of their use has been with small, industrial type settings as opposed to electrical utility power plants. In the past 20 years, this technology has been applied periodically to electric power plant sources.  In electric utility plants firing sulfur-bearing fuel, wet flue gas desulfurization (WFGD) and, in the past decade, selective catalytic reduction (SCR) technologies have been added to control sulfur dioxide and nitrogen oxides emissions. The recent start-ups of new SCR systems on coal-fired power plants have demonstrated an increase of sulfuric acid emissions due to the oxidation of a portion of SO2 across the SCR catalysts.  1 Although the control of sulfuric acid mist from electric utility sources has typically not been regulated, concern and questions regarding these emissions are now being observed.  To read more click download.

In response to the stringent NOx limits for the Houston-Galveston area, and provisions contained in Texas Senate Bill 7, the Texas Electric Utility Deregulation Act, Reliant Energy has developed a plan that will result in implementation of aggressive NOx controls in 2003.  Due to stringent regulatory requirements addressing allowable NOx emission limits for Reliant Energy’s Texas generating units, Sargent & Lundy LLC (S&L) was contracted in mid 1999 to provide a NOx compliance assessment study for the Houston area generating units. In the period of 1997-1999, Reliant Energy W.S. Jones Reliant Energy Houston, Texas, U.S.A. installed various NOx reduction technologies on several Houston-area generating units to meet NOx RACT (Reasonably Available Control Technology) requirements.  To read more click download.