Saving energy with the high efficiency super boiler

The super boiler was developed to reduce emissions and increase efficiency, thus lessening the environmental impact of steam generation. It achieves high efficiency by two approaches: a staged combustion technique which allows lower excess air in combustion, and a novel heat recovery system that recovers both sensible and latent heat from the flue gas stream as well as the water vapor itself. At the current stage of development, up to 94 percent fuel-to-steam efficiency on a higher heating value (HHV) basis can be achieved. The super boiler has the potential to save U.S. industry $4 billion annually in fuel and facility costs while preventing over 140,000 tons of NOx and 20 million tons of greenhouse gases per year. A 300-horsepower (10,000-lb/h steam) boiler is being demonstrated at a manufacturing site in Alabama, and another 300-horsepower boiler field demonstration is scheduled to begin in November, 2007, at a food processing site in California.