EWT™ Plow Blade Scraper Clarifier

The EWT™ Model C3 plow blade mechanism uses the fundamental principal of gravity separation of solids from liquid to produce a clarified overflow water and sludge. The sludge accumulated at the bottom of the clarifier is then scraped and removed. How does it work? Follow the different steps of the sedimentation and withdrawal process described hereafter.

Mixed liquor enters the clarifier through a center column and is discharged into the EquaFlo 360 EDI through influent ports in the center column. 

The EquaFlo 360 EDI dissipates the kinetic energy of the influent mixed liquor flow.  Evenly spaced tangentially oriented vanes at the top of the EquaFlo 360 EDI shell create a controlled and quiescent discharge of the mixed liquor into the flocculating feedwell to enhance flow distribution and flocculation.

The flocculating feedwell promotes flocculation of the mixed liquor suspended solids. It allows for a gradual redirection of the flow velocity into the clarifier and the sedimentation of the flocs creating a sludge blanket at the bottom of the tank.

An EWTTM cast iron oil lubricated drive mechanism mounted on a center column supports and rotates a center cage with truss arms. Each arm supports plow type scraper blades.

The blades transport the sludge accumulated at the bottom of the clarifier toward a sump located at the center of the tank. The sludge is then withdrawn from the sump periodically.

Scum is removed from the surface with a scum skimming system. The skimming system consists of two full radius skimming arm assemblies connected to the center cage and cantilevered from the rotating feedwell and a full radius scum collection trough anchored to the concrete tank wall. The scum is skimmed into the trough and then flushed out of the clarifier twice per revolution with maximum efficiency.

Clarifier sizes: 30’ to 250’ diameter.

Drive design: cast iron base, solid deep gear, oil bath lubrication, up to 35 years of service.

Drive torque capacity: 9,000 ft-lbs to 1,000,000 ft-lbs AGMA 20 years continuous torque.

Rotation speed: 8 to 14 fpm, variable speed available.

Fabrication material: A36 steel, hot dip galvanized steel, 304 & 316 stainless steel

Scum skimming design: conventional scum box, full trough skimmer, rotating pipe skimmer.

Tank configuration: accommodate existing and new tank, steep to flat tank bottom, shallow or deep side water depth

• Low maintenance requirements
• Trouble-free installation 
• Long lasting durable design