The 28th Annual International Pittsburgh Coal Conference will be held at the David L. Lawrence Convention Center on September 12-15. Heyl & Patterson will be part of the conversation, under the topic of Major Demonstration Projects.
Heyl & Patterson Blog
Utilities across the country are seeing increases in the cost of generating and transmitting electricity. With wholesale power bills 8-10% higher than previous years, rising costs are an industry trend – and one that won’t be ending soon.
One power source that can alleviate the problem is lignite, often referred to as brown coal, which has characteristics somewhere between bituminous coal and peat.
Lignite is easier to convert into gas and liquid petroleum products than higher ranking coal, but it is wetter and more susceptible to spontaneous combustrion. This obviously causes problems in transportation and storage. Some processes can remove the latent moisture locked within lignite, and lower the risk of spontaneous combustion to that of black coal, while transforming it into a black coal equivalent fuel.
For Minnesota-based electric energy provider Great River Energy, Heyl & Patterson went one step further, and provided a sustainable, cost-reducing solution utilizing waste energy to simultaneously dry and refine lignite and increase the efficiency of the power plant. The process is called DryFining, or Lignite Fuel Enhancement.
Heyl & Patterson custom-engineered a Fluid Bed Dryer to work with lignite coal and dry it from 38% to 29.5%, utilizing existing and previously wasted energy from within the power plant.
The project began with a single prototype dryer and was later expanded to eight Fluid Bed Dryers.
Designed to process free-flowing material, such as minerals, chemical, plastics, wood products, grain and waste, suspended in a rising flow of air or gas, Fluid Bed Dryers use an energy efficient fluidizing method that causes the material to act like a fluid. This provides a high rate of heat transfer while gently handling the solids. It also provides lower capital equipment and operating costs, with fully automated operation that’s integrated into the plan control system as a result of its efficiencies.
The concept was to dry lignite using a combination of direct and indirect heating, before it is burned in the power plant boiler. Using waste heat from the power plant we were able to dry the coal raising its heating value which in turn makes the power plant operate more efficiently. Overall, the process lowered the customer's nitrogen oxide (NOx) by 20%, sulfur dioxide (SO2) emissions by 35% and significantly reduced the carbon dioxide (CO2) and mercury as well as their overall maintenance costs. Over 400,000 tons of lignite coal has been processed through the prototype with no significant operating or maintenances issues.
The project has been a tremendous success for Great River Energy.
According to a statement issued by the Department of Energy (DOE) regarding the project, “the technology economically captures and uses the waste heat already being produced by the plant to remove water from the coal. By reducing moisture content, less coal is required to generate the same amount of electricity, which means fewer emissions and lower-emission-control costs.”
In 2010, the DryFining team was awarded Power Engineering’s Coal-Fired Project of the Year. Aside from Heyl & Patterson and team leader Great River Energy, the team also included the the Department of Energy's National Energy Technology Laboratory, the Lehigh University Energy Research Center, the Electric Power Research Institute and engineering construction contractor WorleyParsons.
Heyl & Patterson’s Renneburg Division engineers some of the largest Fluid Bed Dryers in the world and are among the most efficient and cost effective dryers on the market. The product line also provides Rotary Dryers, Calciners and Thermal Processors to customers around the world.
To speak with an engineer about DryFining,
FOR IMMEDIATE RELEASE: Pittsburgh, PA – Heyl & Patterson Inc., a specialist engineering company headquartered in Pittsburgh, is part of a team to be awarded with Power Engineering magazine’s 2010 Coal-Fired Project of the Year. The project, “DryFining,” created a new technology for coal-firing power plants that improves fuel quality, decreases volatile gas emissions, and reduces a plant’s operating expenses and maintenance costs.
Recently celebrating 20 years of serving the power industry, Power-Gen International is the industry leader in providing comprehensive coverage of trends, technologies and issues facing the generation sector. As the need to operate more efficiently and cost-effectively becomes increasingly important, no other event bridges challenges with solutions like Power-Gen International.