Constellation Power Source Generation Uses Neural Network Technology to Optimize Cyclone Boilers at its C.P. Crane Station in Baltimore; Cuts NOx Emissions by 25 Percent PITTSBURGH, PA (Sept. 8, 2003) - In a project believed to be among the first of its kind in the United States, Emerson Process Management's Power & Water Solutions industry center has utilized dynamic closed-loop neural network technology to optimize the performance of two units at Constellation Energy's C.P.
Crane station in Baltimore. The results of this project are impressive: Commissioned in May 2003, Unit 2 has experienced a 25 percent average improvement in NOx emissions. Unit 1 was commissioned in July 2003 and results are not yet available. Based on cost savings realized by a reduced need to purchase expensive NOx credits, Constellation recouped its investment in just two months.
Constellation's C.P. Crane station Unit 1 is 200 MW and Unit 2 is 205 MW. Each Babcock & Wilcox boiler has four cyclones in an opposed pair firing configuration. Historically, these types of boilers were more efficient than traditional boiler designs.
However, they produced higher thermal NOx emissions due to greater combustion temperatures in the cyclone. In the late 1990's, natural gas reburn / overfire air systems were installed on both units to reduce NOx emissions. Although the new systems resulted in a 60 to 65 percent reduction in NOx emissions while using the overfire air only, Constellation determined further reductions would be beneficial. This boiler optimization project is being rolled out in three phases. The most critical area, NOx Optimization, was the focus of the first phase.
Emerson, with a rich history in the power industry, has successfully reduced NOx levels at more than 50 units in the United States and abroad. However, this is one of the first projects undertaken on a cyclone boiler design in the United States. For the project, the utility installed Emerson's SmartProcess® optimization software into the station's control systems to further reduce NOx emissions and increase overall unit efficiency. SmartProcess, a suite of intelligent software modules, uses neural network and linear technology to construct a customized plant model that simulates a variety of plant variables under changing conditions and load levels, and then identifies precise control settings for continuous optimal performance.
SmartProcess is capable of working with any distributed control system to provide consistent, reliable results during all plant operation scenarios, including start up, shutdown, load ramps and base load operation. "Because C.P. Crane units are load-following, we needed a product that could dynamically optimize the process during constantly changing demand," said Steven Stultz, senior engineer, Constellation Generation Group. Emerson worked with plant personnel to install and customize the SmartProcess Combustion Optimizer module, then develop a model to interact with the site's existing control systems: Emerson's WDPF® distributed control system on Unit 2, and Emerson's Ovation® Information & Control System on Unit 1.
Analysis of parametric testing, in which several plant variables were manipulated, revealed that several factors - cyclone stoichiometry (a measure of the fuel to air ratio for the combustion process), boiler excess oxygen, boiler air duct pressure and boiler overfired air flow - all had an impact on the NOx production of the boiler. Installation and testing was performed during normal plant operation. Since the boiler optimization for Unit 2 was placed in operation, Constellation has achieved average NOx reductions of 25 percent. And this is expected to further improve, according to Ron Oscher, marketing vice president for the Power & Water Solutions industry center of Emerson Process Management.
"The models will continue to improve over time as more data is collected and modeled," he explained. And that's not all. Constellation should experience additional improvements following the completion of two subsequent phases of the boiler optimization project - the addition of efficiency models to the Combustion Optimizer and the installation of the SmartProcess Steam Temperature Optimizer, according to Oscher. "We anticipate that these two phases will be completed by year's end." About Constellation Energy Based in Baltimore, Constellation Energy Group owns energy-related businesses, including a North American wholesale power marketing and merchant generation business, and the Baltimore Gas and Electric Company (BGE), a regulated energy delivery company in Central Maryland.
In total, Constellation Energy owns 11,300 megawatts of generating capacity. For more information about Constellation Energy, visit www.constellation.com.
About Emerson Process Management Emerson Process Management ( www.emersonprocess.com ), an Emerson business, is a leader in helping businesses automate their production, processing and distribution in the power, water and wastewater treatment, chemical, oil and gas, refining, pulp and paper, food and beverage, pharmaceutical, and other industries.
Emerson's Power & Water Solutions division ( www.emersonprocess-powerwater.com ), formerly Westinghouse Process Control, is a global supplier of advanced distributed process control and information systems. The Pittsburgh-based company is a recognized leader in developing plant-wide process control solutions for the power generation, water treatment and wastewater treatment industries. Power & Water Solutions plays a key role in the Emerson mission of combining superior products and technology with industry-specific engineering, consulting, project management and maintenance services.
Emerson brands include: PlantWeb ; Ovation ; SmartProcess ; Fisher ; MicroMotion ; Rosemount ; DeltaV ; and AMS. About Emerson St. Louis-based Emerson ( www.gotoemerson.com ) is a global leader in bringing technology and engineering together to provide innovative solutions to customers in process control; electronics and telecommunications; industrial automation; heating, ventilating and air conditioning; and appliance and tools.
Sales in fiscal 2002 were $13.8 billion. # # # Ovation, SureService, SmartProcess, PlantWeb, Fisher, Micro Motion, Rosemount, and DeltaV are marks of Emerson Process Management. Other marks are the property of their respective owners.