Purification of Field Wastewater by Filtration.

A filter charge consisting of asbestos waste possesses great ability to retain emulsified oil and mechanical impurities in comparison with quartz sand. The grain size of this waste should lie in the range from 0. 5 to 2 mm, while the inhomogeneity factor should range from 1. 5 to 1. 6. The thickness of the working layer of the charge without allowing for supporting layers should be taken equal to 0. 7 m. The filtering of the wastewater can occur only after it has undergone a settling treatment and has an emulsified oil content of no more than 100 mg/liter. The surface tension of the water at the water-oil interface should be no less than 12 mN/m.