Abstract: Orthogonal experiments were carried out to determine the optimal mass ratio of various components in the solidified wastewater, and to study the effects of different water samples on the properties of the blocks. Taking the concentrated desulfurization wastewater as the blending medium, the chloride ion binding ability of the solidified desulfurization wastewater was researched. Results show that the optimal mass ratio of the solidified body is as follows:cement:fly ash:high-salt brine:sand=0.97:0.17:0.60:0.98; the Friedel's salt formed by the reaction of Cl^- in water with C₃A in cement could increase the compressive strength of the blocks; the sulfate in concentrated FGD wastewater reduces the Cl^- binding capacity and increases the Cl^- leaching rate of the blocks; solidified blocks with high content of free Cl^- could be taken as the non-reinforced materials or road stones, etc.