Evaluation of pollutant characteristic when choosing wastewater treatment methods

Summary

The variety of pollutant characteristics in industrial effluents is considered. When choosing a treatment method in each particular case the evaluation of pollutants with testing the indicators that characterize mineral particles in suspended phase is required. Their correlation described by the first- and second order equations is disclosed. The dependences used at present for the recalculation of the laboratory data on particle hydraulic size that should be separated to provide for the required precipitation effect with the purpose of calculating the geometry of the facilities included into the project are considered. The conclusion is drawn about possible errors of the applied method of precipitation process modeling. On the basis of the research results a new indicator is suggested – agglomeration index that characterizes agglomeration capability of pollution suspended particles. The technique of its determining and the method of recalculating laboratory data on hydraulic size obtained for the layer depth differing from the settling level in the applied facility with account of the agglomeration of pollution suspended phase are presented. As shows the experience of evaluating many designed projects and technical solutions the authors of which have participated in tenders a large number of these solutions are not supported by the analysis, do not have enough proofs and are often a fortiori incorrect and consequently cheap. Therefore tender boards find difficulties in making an objective choice.

Key words

suspended substances , Agglomeration , wastewater , settling kinetics , agglomeration index , hydraulic size