The process, based on SBS Injection (sodium-based solution) technology, enables power plants to realize operational cost savings by burning less coal. It also results in less coal combustion residual wastes and lower air pollution emissions.
The SBS technology injects sorbent into the combustion system, removing sulfur trioxide (SO3) prior to the selective catalytic reduction system and/or air preheater. It improves plant operational performance and reliability, enhancing the capture and removal of mercury while helping the plant to meet stringent sulfuric acid emission limits. By eliminating sulfuric acid and other compounds from the flue gas, which lead to fouling and corrosion of air preheater equipment in the power plant, the performance and efficiency of the equipment can be improved, URS says.
Working with a leading supplier of air preheaters for the power industry, long-term testing of the SBS technology has successfully shown recovery of thermal energy from combustion gases down to temperatures as low as 220°F, corresponding to an improvement in overall plant efficiency of up to 3 percent or approximately a 300 Btu/MW-hr. heat rate reduction, the company says. To achieve maximum efficiency gains, most plants will require relatively simple modifications to the air preheater.
In April, URS won a National Grid contract to develop a framework on natural capital and ecosystem services — a system that will place a value on the goods and services provided by nature.