The limestone emission control (LEC) system has ademonstrated capability to greatly reduce sulfur dioxide (SO2)emissions, a major contributor to acid rain, from both utility andindustrial sources. The LEC also removes particulate matter. Thisproject's objective is to greatly improve the capability to removeparticulate matter by precharging the dust entering the LEC; thus,utilities and industry may save billions of dollars in equipmentand operational costs. Many utility and industry coal-firedboilers use electrostatic precipitators (ESPS) alone, which are not capable of removing @ and many older ESPs will require upgrading inthe 1990s to meet more stringent particulate standards. Tests of a patented LEC system demonstrate greater than 90% S02 removal capability. LECs can be placed downstream of ESPS, and it isbelieved, the precharged LEC can also remove fine flue gasparticulates, which pose the greatest health hazard and are themost difficult to capture. Phase I of this project will involveexperiments on a bench scale device and on a pilot plant, to testfor increased particulate removal (especially submicrometer)because of precharging. The bench scale device will be speciallyconstructed for this project. The pilot plant will be an existingLEC system, modified to include an inlet electrical precharger.Anticipated Results/Potential Commercial Applications as described by the awardee:If the precharged LEC, as modified, is capable ofsignificant fine particulate removal, the LEC would provide bothS02 removal capability and improved particulate removal @onnarwe toexisting ESPS. Further, an ESP/LEC combination would be alower-mst alternative to spray dryer/baghouse combinations. If LECfine particulate removal performance is sufficiently high, it mayeven be possible to use the LEC as a stand-alone particulate andS02 removal device. TUs will make it suitable not only as an acidrain retrofit technology, but also as a stand-alone New SourcePerformance Standard (NSPS) technology for new installations.
