Underground water conditioning for utility and drinking water supply of oil refinery producing area

Summary

The results of experimental studies of conditioning underground water containing high iron concentrations for utility and drinking water supply of oil refinery producing area are presented. At the first stage the exact values of underground water pH and redox potential of the medium were defined in order to evaluate the potential of using different deironing-demanganation processes. A specially designed flow-through temperature-controlled cell was used for measurements. The comprehensive technology of chemical treatment developed earlier for conditioning underground water at the Tumen North here again ensures the standard quality of drinking water. In the process of removing iron and manganese from water with simultaneous stabilization the chemicals having RF certificates for drinking water supply are used: hydrogen peroxide (GOST 177-88), potassium permanganate (ANSI/AWWA 603-88 standard) and caustic soda (GB 5175-2008 standard). The use of stabilization treatment provides for the elimination of secondary pollution with iron in the distribution network. Separation of insoluble reaction products was carried out by filtration through granular bed (quartz sand of 0.5–1.2 mm fraction). The obtained correlations between redox potential and chemical dosages allow to automatize the dosing process. In this case the technology provides for the residual concentration of iron and manganese less than 0.1 mg/l in drinking water. As an additional effect the technology ensures reducing the concentration of pollutants of technogenic origin– anionic surfactants (75%) and oil products (90%). Thereby the residual concentration meets the standard for bottled water. On the basis of the carried out tests the Process regulations for designing facilities for underground water conditioning of 4800 m³/day capacity were developed.

Key words

deferrization , ground water , demanganization , stabilization treatment , removal of technogenic pollutants