Importance

Loading Importance Indicators...

Abstract

A process and apparatus for the chemical-mechanical treatment and purification of ground and surface waters and effluents of various types employs adding materials for coagulation, flocculation, precipitation, sedimentation and altering the pH value. The process comprises separate process stages carried out successively as follows: (1) a first initial process stage wherein certain additives are admixed to the raw water by stirring; (2) a second initial process stage wherein contact sludge is admixed by stirring; (3) a third initial process stage wherein a flocculent aid and possibly also at least some of the other materials added in the first stage are admixed by stirring with high energy input; and alternatively (4) a fourth initial process stage for the formation of course flocs and completion of reaction of the previously added materials and formation of settleable particles and conglomerations of particles together with adsorbed and attached and occluded raw water components with moderate movement. After the initial process stages a further stage occurs wherein flocs and reaction products and raw water components are separated from the clarified water with separate removal of the separated solids and the clarified water. The separation of flocs and reaction products and raw water components from the clarified water in the further zone is accomplished by inclined sedimentation means and at least a part of the sludge is concentrated to a solids concentration of at least 1% weight/volume after drying with at least a part of the concentrated sludge being returned as contact sludge in the second initial process stage.

Loading the Abstract Image...

First Claim