Thickeners high-density

Clarmer-Thickener Clarifiers can serve as thickeners, achieving additional densification in a deep sludge sump adjacent to the center that extends a shoi t distance radi ly and provides adequate retention time and pulp depth to compact the solids to a high density. Drive mechanisms on this type of clarifier usually must have higher torque capability than would be supplied on a standard clarifier. 

Selection of Type of Thickener or Clarifier Selection of the type of unit thickener or clarifier depends primarily on the optimization of performance requirements, installation cost and operating cost. For example, the inclined-plate type of clarifier provides for less solids-holding capacity than a circular or rectangular clarifier, but at a lower installation cost. The high-density thickener maximizes underflow solids concentration, requiring a higher torque rating than conventional thickeners. 

Thickener Types Flocculants are commonly used in thickeners, and this practice nas resulted in thickener classifications as conventional, high-rate, ultrahigh-rate, or high-density. These designations can be confusing in that they imply sharp distinction between each type, which is not the case. 

The ultrahigh-rate (rakeless) thickener uses internal cones to achieve the tilted-plate effect. The design allows internal flocculation. The tank is tall, with a 60° bottom cone, providing sludge compression height and volume, resulting in a high-density underflow. 

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