||Scale control in limestone wet scrubbing systems /
Wen, C. Y. ;
McMichael, W. J. ;
Nelsen, Jr, R. D. ;
Berkowitz, J. B. ;
||Little (Arthur D.), Inc., Cambridge, Mass.;National Environmental Research Center, Research Triangle Park, N.C. Control Systems Lab.;West Virginia Univ., Morgantown.
|| U.S. Environmental Protection Agency, Office of Research and Development,
||EPA 650-2-75-031; ADL-C-75092; EPA-68-02-1013; EPA-ROAP-21ACY-038
Sodium sulfate. ;
Calcium sulfate. ;
Scrubber (Chemical technology) ;
Sodium sulphate ;
Air pollution control equipment ;
Corrosion prevention ;
Calcium inorganic compounds ;
Reaction kinetics ;
Sulfur dioxide ;
Calcium carbonates ;
Inorganic phosphates ;
Limestone scrubbing ;
||Some EPA libraries have a fiche copy filed under the call number shown.
||vi, 91 pages : illustrations ; 28 cm.
The report gives results of tests of a number of phosphate and polymeric additives--which have proven effective in controlling scale in some commercially encountered calcium-containing systems--for scale control potential in limestone wet scrubbers. Additives selected were Lime Treet; Acrysol A-1, A-3, A-5; Calnox 214 DN; Darex 40; Dequest 2000; PD-8; sodium hexametaphosphate; Calgon CL-14; sodium pyrophosphate; Versenex 80; Quadrol; and sodium tripolyphosphate. The kinetics of oxidation of calcium sulfite in clacium carbonate/sulfite slurries was studied and compared with the oxidation of sodium sulfite solutions. Rates of oxidation in the calcium system, found to be proportional to bisulfite ion concentration, increased in the presence of solid calcium sulfite. Therefore the rate of sulfite dissolution is a contributing factor to the oxidation under normal operating conditions. Cationic impurities, such as sodium or magnesium, which can increase bisulfite concentration in solution in the 5-6 pH range, are expected to accelerate oxidation.
EPA Project Officer: R.H. Borgwardt. Arthur D. Little, Inc. Prepared for the U.S. Environmental Protection Agency Contract Number: 68-02-1013 "April 1975." "EPA 650-2-75-031." Cover title. Control Systems Laboratory, National Environmental Research Center. Also distributed by National Technical Information Service (NTIS) as PB243309.