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Reusing reclaimed municipal wastewater as circulating cooling water is one of the effective ways to solve the water resource shortage. This paper investigated into the relationship between water quality and corrosion and scaling. Furthermore, after investigation on lime coagulation, we proposed use soil-aquifer treatment (SAT) as a new wastewater reclamation process for circulating cooling water, and the study focused on it.This paper is divided into three stages. The fist stage the relationship between water quality and corrosion and scaling was studied by static experiment. In the second stage, beaker experiment was used to study the optimum operation parameters of lime coagulation, and the effluent was applied to circulating simulator to investigate the water quality, corrosion and scaling conditions of the cooling pipe.Results of static test indicated that, in corrosion, and varied similarly, the corrosion rate changed slowly at mid-concentration; Ca2+ and HCO3- at low concentration could inhibit corrosion. In scaling, fouling quantity varied closely with the concentration of Ca2 + and HCO3- ; had not generated precipitation with Ca2 + as some literature indicated; organic matter had a very small effect on corrosion and scaling. Cl -SO42-2-SO4Results of lime coagulation indicated that, the dosage of lime at 1.25 times of the theoretical calculations, dosage of PFS at 20mg/L is the optimum chemicals- feeding quantity when water quality is in the experimental conditions. And the removal rate of hardness, alkalinity, SS and COD is 25.86%, 40.00%、77.39%、39.98% respectively. But to and , the removal rate was bad. In the process of operation when the effluent was used in the circulating simulator, pH, the concentration and remained stable with the concentration multiple,but the harness and alkalinity decreased. And the corrosion rate, the fouling, Cl -SO42-Cl -SO42-relative percentage content of Fe and organic matter was decreased compared to the secondary effluent used.The results of soil aquifer treatment indicated that, the removal rate of SS, COD, Cl - and SO24-was 95.25%、64.86%、38.46%、38.33% respectively when the secondary effluent was treated with the SAT system. And when the effluent of SAT system was used in the circulating simulator, the PH, hardness and alkalinity remained stable with the change of concentration multiple, while the concentration of and changed with concentration multiple closely. The corrosion rate, fouling and the relative percentage content of Fe and organic matter decreased from 0.336mm/a, 2.16g, 46.90% and 14.84% or 0.160mm/a, 1.56g, 43.12%, 11.75% when the secondary effluent and the lime coagulation effluent was used as cooling water respectively compared to 0.086mm/a, 0.97g, 37.76% and 8.70% when SAT system effluent was used. That verified the SAT system has a better performance compared to lime coagulation.Cl -SO42-
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