IECMQ: a computer program for calculating equilibrium-state in aqueous systems

The present computation determines the phase-compositions (partial pressures, molalities or activities) and respective amounts of gaseous, aqueous, and solid phases occurring in the equilibrium system; the method is illustrated by the wet flue-gas (power-plants, furnaces) desulfurization system that employs a slurry of lime and natural waters. Hot flue-gas consisting of N(2), O(2), CO(2), H(2)O(g), NO, N(2)O, SO(2), SO(3), and HCl is scrubbed with the Ca(OH)(2)-slurry to convert sulfur oxides to sulfite (CaSO(3). 1/2H(2)O) and sulfate (CaSO(4). 2H(2)O) products. The calculation considers 10 gaseous species SO(2), SO(3), HCl, CO(2), NO, N(2)O, N(2), O(2), H(2)O(g) and HNO(2) - 11 non-ionic aqueous species - SO(2)(aq), SO(3)(aq), HCl(aq), CO(2)(aq), NO(aq), N(2)O(aq), N(2)(aq), O(2)(aq), H(2)O(aq), HNO(2)(aq) and HNO(3)(aq) - 11 ionic aqueous species HSO(3)(ag),HSO(4)(2-)(aq), Cl(-)(aq), HCO(3)(-)(aq), CO(3)(2-)(aq), NO(3)(-)(aq), NO(2)(-)(aq), OH(-)(ag), H(+)(aq), Ca(2+)(aq) and SO(3)(2-)(ag) - and two solid phases. The effect of the Ca(OH)(2)-content on sulfur-partition between the sulfite and sulfate phases was investigated. (C) 2000 Elsevier Science B.V. All rights reserved.