Plate Clarifiers

Tilted-Plate Clarifiers Lamella or tilted-plate separators have achieved increased use for clarification. They contain a multiplicity of plates inchned at 45 to 60° from the horizontal. Various feed methods are employed so that the influent passes into each inchned channel at about one-third of the vertical height from the bottom. This results in the solids having to settle only a short distance in each channel before sliding down the base to the collection zone beneath the plates. The clarified liquid passes in the opposite direction beneath the ceiling of each channel to the overflow connection. 

The principal advantage of the tilted-plate clarifier is the increased capacity per unit of plane area. Major disadvantages are an underflow solids concentration that generally is lower than in other gravity clarifiers and difficulty of cleaning when scahng or deposition occurs. The lower underflow composition is due primarily to the reduced com-... 

FIG. 18-131 Disk-and-plate clarifying-filter assembly. (Alsop Engineering Co.)... 

Rake The purpose of the rake is twofold direct the settled solids to the blowdown and to control the character of the sludge bed. High rake speed results in a fluffier bed while low speed hinders the contact between newly-formed floe (agglomerated suspended solids) and the bed. Note that most inclined-plate clarifiers do not have this feature. 

Inclined plate clarifiers, also known as Lamella clarifiers, use several inclined plates (or sometimes tubes) to maximize the settling area for a given floor area (Lamella is a registered trademark of Parkson Corporation, Ft. Lauderdale, FL). Figure 8.5 shows a diagram of an inclined-plate clarifier. 

Figure 8.5 Inclined-plate clarifier. Courtesy ofParkson Corporation.

Inclined-plate clarifiers have five treatment zones ... 

Rise rate is about 2.0 gpm/ft2in an included plate clarifier. 

Inclined plate clarifiers. KWM Wastewater Technologies, Evanston, Illinois, www.koch-water.com/clar.html. 

Blanket clarifier Circular clarifier inclined plate clarifier Rectangular clarifier Vertical flow clarifier... 

Figure 14 Schematic of a tilted-plate clarifier (Heil Process Equipment Co.). (From Schweitzer, 1997.)...

---