Schreiber’s Peripheral Drive Clarifiers are favored because of their ability to accomplish rapid sludge removal and continuous collection and removal of floatables. Instead of the typical center-drive high torque arrangement, Schreiber Clarifiers utilize the mechanical leverage and mechanical simplicity of a peripherally driven system. A low horsepower single drive unit is all that is needed to rotate both the scraper and the skimming assemblies. The assemblies are suspended from a rotating access bridge or, in the case of smaller units, a lightweight rotating beam arm. The rotating skimming equipment removes floatables regardless of wind direction, and the helical scrapers convey settled solids to the center of the basin for removal in one revolution or less.

Additional accessories such as effluent weirs, baffles, and return sludge pumps ensure compatibility in all applications. As in all of our products, our clarifiers are designed for the hoisting of all underwater equipment above the water level for inspection and or maintenance without dewatering the basin. For corrosion protection, our clarifiers are hot-dip galvanized and all of the hardware is stainless steel.

Other available options include weir cleaning systems, fabricated flocculation tanks and inlet feed wells.

Our Bridge Clarifiers serve basins ranging in size from 20’ to 200’ in diameter. As a result of the leverage achieved by the peripheral drive design, only one, small, 0.5 to 1.0 hp, drive motor is required – even for clarifiers as large as 200’ in diameter.

Our Beam Clarifiers are designed for smaller, 20’ to 90’, diameter basins.  In these smaller units, a fabricated beam is employed, instead of a bridge, to pull the helical scrapers along the floor of the clarifier. The beam clarifier, which requires only a 0.5 hp drive, is used for our GR configurations and for those applications that require a fixed access bridge.


  • Rapid sludge removal via helical scrapers which move sludge to center hopper in one revolution.
  • Retrievable underwater assemblies allow maintenance with dewatering the tank.
  • Peripheral drives preclude the high torque issues inherent with center drive units.
  • Drive wheel serves as a natural clutch by spinning, if obstructions are encountered.
  • Bridge load is equally split between center bearing and outside wall
  • Proven Long-Lasting Equipment and Low Maintenance Design
  • Wheeled scrapers, that are pulled, rather than pushed, accommodate irregular clarifier floors eliminating the need for grouting.


  • Wastewater Primary Clarification
  • Wastewater Secondary Clarification
  • Drinking Water Clarification
  • Sludge Thickening
  • Anywhere a clarifier is needed