GB752077A - Improvements in or relating to apparatus for use in water purification treatment or like processes - Google Patents

Abstract

752,077. Purifying liquids. BRISTOW, A. W. April 13, 1954 [June 1, 1953], No. 15254/53. Class 46. Water, with chemicals added to precipitate dissolved matter and to coagulate suspended matter, enters, through pipes 22, Fig. 4, and 23, Figs. 4 and 5, the divergent chamber 25 of a mixing device 24. Further mixing occurs in four convergent chambers each constituted by a wall of a skirt 26 and adjacent portions of two intersecting strips 29 extending diagonally across the skirt and supporting a baffle plate 28. Still further mixing takes place in the lower end of a cell 18 constituted by an inverted square-based pyramidal cavity in a concrete block 13. Coagulation occurs here and the water flows upward, supporting the sludge blanket so formed, in a tank 11. Purified water flows away by troughs 36, Fig. 4, to filters (not shown) while the level of the sludge blanket is controlled by sludge draw-off pipes 34, Fig. 4. The two parts of the mixing device 24 are preferably square based pyramidal and it is then located with its sides parallel to those of its cell by extensions (through the corners of the skirt 26) of the strips 29. The baffle 28 is accordingly square with its sides parallel to the sides of the device 24. In a modification of the device the upper end is completely closed while the inlet pipe penetrates the baffle and discharges towards the upper end. The cells 18 preferably have parallel-sided upward extensions 17.