Chloride Ion Removal from the Wet Flue Gas Desulfurization and Denitrification Wastewater Using Friedel’s Salt Precipitation Method

Table 1

Experimental conditions of the individual experiments.

Number	Experiment	Experimental conditions
1	The effect of NaAlO2 dosage	Vsolution = 1 L, [Cl^−] = 2000 mg/L, Treaction = 25°C, stirring = 400 r/min, t = 30 min, initial pH = 7.0.
2	The effect of Ca(OH)2 dosage	Vsolution = 1 L, [Cl^−] = 2000 mg/L, Treaction = 25°C, stirring = 400 r/min, t = 30 min, initial pH = 7.0.
3	The effect of the solution’s initial pH	Vsolution = 1 L, [Cl^−] = 2000 mg/L, Ca/Al/Cl molar ratio = 6 : 3 : 1, Treaction = 25°C, stirring = 400 r/min, t = 30 min.
4	The effect of the solution’s temperature	Vsolution = 1 L, [Cl^−] = 2000 mg/L, Ca/Al/Cl molar ratio = 6 : 3 : 1, stirring = 400 r/min, t = 30 min, initial pH = 7.0.
5	The effect of reaction time	Vsolution = 1 L, [Cl^−] = 2000 mg/L, Ca/Al/Cl molar ratio = 6 : 3 : 1, Treaction = 25°C, stirring = 400 r/min, initial pH = 7.0.
6	The effect of stirring speed	Vsolution = 1 L, [Cl^−] = 2000 mg/L, Ca/Al/Cl molar ratio = 6 : 3 : 1, Treaction = 25°C, t = 30 min, initial pH = 7.0.
7	The effect of SO4^2− concentration	Vsolution = 1 L, [Cl^−] = 2000 mg/L, Ca/Al/Cl molar ratio = 6 : 3 : 1, Treaction = 25°C, stirring = 400 r/min, t = 30 min, initial pH = 7.0.
8	The effect of F^− concentration	Vsolution = 1 L, [Cl^−] = 2000 mg/L, Ca/Al/Cl molar ratio = 6 : 3 : 1, Treaction = 25°C, stirring = 400 r/min, t = 30 min, initial pH = 7.0.
9	The effect of NO3^− concentration	Vsolution = 1 L, [Cl^−] = 2000 mg/L, Ca/Al/Cl molar ratio = 6 : 3 : 1, Treaction = 25°C, stirring = 400 r/min, t = 30 min, initial pH = 7.0.
10	The effect of precipitated solid reuse	Vsolution = 1 L, [Cl^−] = 2000 mg/L, Ca/Al/Cl molar ratio = 6 : 3 : 1, Treaction = 25°C, stirring = 400 r/min, t = 30 min, initial pH = 7.0.
11	Removal of chloride ion and other ions in actual DDW	Two-stage Freund’s salt precipitation method: (1) First stage mainly removed SO4^2−, Vsolution = 1 L, Ca/Al/S molar ratio = 4 : 1 : 1, Treaction = 25°C, stirring = 400 r/min, t = 30 min. (2) Second stage mainly removed Cl^−, Vsolution = 1 L, Ca/Al/Cl molar ratio = 6 : 3 : 1, Treaction = 25°C, stirring = 400 r/min, t = 30 min.