The Use of a Turbulent Pipe-Flow for Rapid Flocculation of Precipitate in the Electroplating Wastewater Treatment

The paper presents the results of an experimental pilot study on advanced flocculation of metal hydroxides that are precipitated from electroplating wastewater during pH-adjustment. A pipe-flocculator with a turbulent flow, to ensure proper mixing conditions, was used instead of a classical flocculation tank. The results of the study indicated a high efficiency of the process. The flocculation proceeded within 50-100 seconds, which was much less than is required during classical flocculation. Application of a pipe-flocculator results also in reduction of both capital and operating costs of the wastewater treatment plant. In conclusions, important conditions, which are indispensable if pipe-flocculation is to be used, were formulated.