Chemical and physical characterization of western low-rank-coal waste materials

Abstract

Evaluations of disposal requirements for solid wastes from power stations burning low-rank western coals is the primary objective of this program. Solid wastes to be characterized include: fly ashes, sludges from wet scrubbers, solids from fluidized bed combustion (FBC) processes and solids from dry scrubbing systems. Fly ashes and sludges to be studied will be obtained primarily from systems using alkaline fly ashes as significant sources of alkalinity for sulfur dioxide removal. Fluidized bed combustion wastes will include those produced by burning North Dakota lignite and Texas lignite. Dry scrubbing wastes will include those from spray drying systems and dry injection systems. Spray dryer wastes will be from a system using sodium carbonate as the scrubbing reagent. Dry injection wastes will come from systems using nahcolite and trona as sorbents. Spray dryer wastes, dry injection wastes, and FBC wastes will be supplied by the Grand Forks Energy Technology Center. Sludges and other samples will be collected at power stations using fly ash to supply alkalinity to wet scrubbers for sulfur dioxide removal. Sludges will be subjected to commercial fixation processes. Coal, fly ashes, treated and untreated sludges, scrubber liquor, FBC wastes, and dry scrubbing wastes will be subjected to amore » variety of chemical and physical tests. Results of these tests will be used to evaluate disposal requirements for wastes frm the systems studied.« less