Method for treating liquid used for absorbing gaseous sulfur dioxide in the process for desulfurization of combustion exhaust gas
First Claim
1. A method for treating a liquid used for absorbing gaseous sulfur dioxide in the wet process for desulfurization of a combustion exhaust gas of the gypsum-by-producing type so as to remove chloride ions from said liquid wherein said liquid has been saturated with gypsum, has dissolved at least magneisium sulfate and magneisium chloride and has been used for absorbing gaseous sulfur dioxide, the method comprising the steps of conducting a clarification treatment and afterward passing said liquid through an electrodialyzer having three dialyzing chambers which comprise one sheet of cation-exchange membrane and two sheets of membrane selectively permeable to monovalent anions as one unit, and thereby selectively separating and removing chloride ions fom said liquid as an aqueous solution of magnesium chloride of a high concentration.
1 Assignment
0 Petitions
Accused Products
Abstract
Disclosed herein is a method for treating a liquid used for absorbing gaseous sulfur dioxide in the wet process for desulfurization of a combustion exhaust gas of the gypsum-by-producing type, which method comprises the steps of, after subjecting a liquid, which has been saturated with gypsum, has dissolved at least magnesium sulfate and magnesium chloride and is used as the above-mentioned liquid for absorbing gaseous sulfur dioxide, to clarifying treatment, passing the liquid saturated with gypsum through an electrodialyzer having three dialyzing chambers comprising one sheet of cation-exchange membrane and two sheets of membrane selectively permeable to monovalent anions as one unit, thereby selectively separating and removing the chloride ion in the above-mentioned liquid as an aqueous solution of magnesium chloride of a high concentration.
12 Citations
9 Claims
- 1. A method for treating a liquid used for absorbing gaseous sulfur dioxide in the wet process for desulfurization of a combustion exhaust gas of the gypsum-by-producing type so as to remove chloride ions from said liquid wherein said liquid has been saturated with gypsum, has dissolved at least magneisium sulfate and magneisium chloride and has been used for absorbing gaseous sulfur dioxide, the method comprising the steps of conducting a clarification treatment and afterward passing said liquid through an electrodialyzer having three dialyzing chambers which comprise one sheet of cation-exchange membrane and two sheets of membrane selectively permeable to monovalent anions as one unit, and thereby selectively separating and removing chloride ions fom said liquid as an aqueous solution of magnesium chloride of a high concentration.
Specification