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Despite well-known corrosion inhibition behavior of cathodic protection (CP) system, this process might be a potential hazard to surrounding ecosystem resulted mostly from continuous electrical current which is applied to the adjacent environment and metallic anode dissolution as well. In this research, deepwater CP wells at different locations of Golestan province, Iran, were taken into consideration to evaluate the impact of these protective systems on underground waters from viewpoint of chemical and physicochemical characteristics resulted from anode dissolution. For this purpose, concentration of metallic constituents of the anode as well as the amount of pH, total dissolved solids (TDS), electrical conductivity (EC), and total hardness were determined. On the basis of obtained results, the concentration of Mn, Cr, and Fe in CP well located nearby an industrial district (i.e., 0.087, 0.475, and 8.5 mg/L, respectively) was higher than both WHO and USEPA standards. This fact can be resulted from the position where the well was dug as well as the CP anode dissolution within the deep CP water wells.

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The present paper aims to examine the method used to calculate the flash temperature of binary mixtures containing alcohol−alcohol and alcohol−acid based on activity models of Wilson, UNIQUAC and NRTL. The binary interaction parameter is obtained by group contribution method in these equations. The advantage of this method is that the methods used to calculate the flash temperature are based on the activity coefficients and the binary interaction parameter are independent from VLE experiments and phase equilibria. These parameters may be obtained from group contribution methods for calculation of flash temperature of binary mixtures containing alcohol. Therefore, 12 binary mixtures containing 97 binary flash data were used; for the three models of Wilson, NRTL, and UNIQUAC, adjustable parameters were obtained by a similar method using group contribution method and it was later tested for three activity equations and 4 mixtures containing 33 binary flash data. Test results indicate that the overall average absolute relative deviation and average absolute deviation for normal butanol/normal pentanol, normal pentanol/propionic acid, and isobutanol/propionic acid when the fitted coefficients are used by equilibrium data are, respectively, equal to 3.6 K and 1.11%, 1.39 K and 0.43%, and 1.11 K and 0.34%. When the binary interaction parameters were obtained using group contribution method (the present work), the results were, respectively, 1.03 K and 0.33%, 1.02 K and 0.32%, and 1.11 K and 0.35%. Moreover for isobutanol/normal pentanol mixture with equilibrium data, the group contribution method was solely applied which was highly consistent with experimental data on flash temperature.