Case Studies

H&P’s Fluid Bed Dryer Dries and increases the BTU’s of Lignite Coal

Utilities across the country are seeing increases in the cost of generating and transmitting electricity. With wholesale power bills 8-10 percent higher than the previous year. Unfortunately, rising costs are an industry trend – and one that won’t be ending soon.

Fortunately for one Minnesota based wholesale electric energy provider, Heyl & Patterson was able to help provide a sustainable, cost-reducing solution utilizing waste energy to dry lignite which increased the efficiency of the power plant.

Working together with the customer, we were able to custom engineer our Fluid Bed Dryer to work With their lignite coal and dry it from 38% to 29.5% utilizing existing energy from within the power plant which was previously wasted said Jeff Morris Vice President of the Renneburg Division of Heyl & Patterson Inc.

Heyl & Patterson’s Fluid Bed Dryer

This project was initially started with a single prototype dryer and has been expanded with 8 Fluid Bed Dryers. Heyl & Patterson’s Renneburg Division make some of the largest Fluid Bed Dryers in the world and are among the most efficient and cost effective dryers and on the market. The Renneburg Division of Heyl & Patterson Inc. provides Dryers, Cooler, and Calciners to thermal processing customer around the world. Heyl & Patterson Inc. is based in Pittsburgh PA and was founded in 1887.

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, the dryers use an energy efficient fluidizing method that causes the material to act like a fluid. In turn, 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.

Heyl & Patterson’s Contribution

“The concept was to dry – using a combination of direct and indirect heating - the lignite coal before it is burned in the power plant boiler,” said Morris. “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 customers NOx by 20%, SO2 emissions by 35% and significantly reduced the CO2, and mercury as well as their overall maintenance costs.” Over 400,000 tons of lignite coal has been processed thru the prototype with no significant operating or maintenances issues.

The End Result

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.”