Clarifiers are settling tanks built with mechanical means for continuous removal of solids being deposited by sedimentation. A clarifier is generally used to remove solid particulates or suspended solids from liquid for clarification and (or) thickening. Concentrated impurities, discharged from the bottom of the tank are known as sludge, while the particles that float to the surface of the liquid are called scum.
Clarification is the oldest and most widely used operation in the effective treatment of wastewater. The operation consists of removing sediment, turbidity and floating material from raw wastewater.
The two types of wastewater clarifiers provided by Watermax are parallel plate and the circular mechanical type described below. There are also two types of circular mechanical clarifiers offered by PCS: circular center feed, and circular peripheral flow types.
The SLWS circular mechanical clarifiers include circular center feed, and circular peripheral flow types.
Circular Center Feed Wastewater Clarifiers
The SLWS circular center feed clarifier operates with the effluent entering through a center stilling well with the flow being forced downward. This ensures the proper residence time of the water in the clarifier to allow for the settling of the solids. The water then rises and exits through a wall mounted weir trough that is placed on the inner circumference of the clarifier. A skimmer sweeps over the surface of the clarifier to collect any floatable solids and removes them via the scum trough. A scraper arm assembly passes over the bottom of the clarifier to densify and condition the settled solids prior to being drawn off for additional processing.
Circular Peripheral Flow Wastewater Clarifiers
The circular peripheral flow clarifier offered by PCS operates with the water flow entering the system at the periphery. The water flow is evenly distributed and spirals down around the annulus of the clarifier by means of a specially designed baffle skirt. This configuration provides for maximum settling of solids toward the sludge pick-up. The water flow exits the clarifier through a center supported weir trough. A scraper arm assembly sweeps the bottom of the clarifier to densify and condition the settled solids prior to being drawn off for additional processing.
circular center feed and circular peripheral flow clarifiers offer the user a variety of features and applications. PCS circular clarifiers are found in municipal, commercial, and industrial applications; they can be used for primary and secondary clarification; and they are available in steel or the internal components can be packaged for installation in a concrete construction (concrete by others).
Circular Center Feed
Flow enters through the center stilling well and is forced downward, ensuring a proper settling time before it rises and exits through the wall-mounted weir troughs. The skimmer covers the surface of the clarifier between the center stilling well and the scum baffle.
Circular Peripheral Flow
Flow enters at the periphery, where it is evenly distributed and spiraled downward around the annulus by means of the specially designed baffle skirt, providing for maximum settling toward the sludge pickup. Flow exits through the center-supported weir troughs.