Sale of fly ash is a flourishing business for many electric utilities. In fact, some 12 million tons of fly ash produced by coal-fired electricity plants in the U.S. are sold to the cement and concrete industries. However, this business may be in danger. Many utilities find that nitrogen oxide (NOx) reduction equipment installed to meet Clean Air Act emissions standards can increase the unburned carbon content of fly ash, making it unmarketable. A new technology, Carbon Burn-Out (CBO), could solve this problem. Designed around fluidized-bed combustion, the process provides temperature, residence time, and oxygen content at values optimized for fly ash carbon combustion. The system's hot restart and cycling capability is similar to that of fluidized-bed steam generators in its ability to quickly recover from a trip condition or short-term forced outage. Not only does CBO produce a high-quality, low-carbon fly ash, but the heat recovered in the process improves the efficiency of the host power plant. Based on successful tests conducted by the Electric Power Research Institute (EPRI) at a pilot plant operated by South Carolina Electric & Gas, the utility has constructed a full-scale facility designed to produce about 160,000 tons of the low-carbon fly ash per year. E-mail firstname.lastname@example.org.
Applied Research Associates has delivered several of its Pointman Tactical Robots to the CBP in Tucson, which the agency is using to explore drainage tunnels that run between Nogales, Ariz., and Nogales, Mexico. These tunnels are out of sight from border surveillance and are increasingly being used for illegal activity.