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The Trident High Solids Contactor (HSC) designed by Siemens Water Technologies is a high rate, solids contact clarifier employing buoyant media capable of operating at loading rates of 8 to 18 gpm/ft2, as piloted in Foundation Project # 3114. The Trident HSC system includes chemical addition followed by removal of particulate material in two clarification stages. The first stage includes a tube settler section followed by passage of the partially clarified water upward through a bed of buoyant plastic media that the manufacturer describes as an "adsorption clarifier" (AC). Five to ten percent of solids collected from tube settler section are recirculated to the front of the process, thereby promoting additional solids contact prior to clarification in the tube settler portion of the process. The subsequent AC portion of the process provides additional mixing, contact flocculation, and solids removal. In other applications, the clarified water from AC will pass through filtration and UV disinfection stages (see schematic links below). In all applications, the combined residuals solids from the tube and AC clarification sections produces less than one percent solids, typically on the order of 0.5 percent. Characteristics of the Trident HSC system demonstrated during this study include:

  • Hydraulic loading rate of up to 6 gpm/ft2 in the tube section and up to 18 gpm/ft2 in the "AC" section
  • Median turbidity <1 ntu and 95th percentile turbidity <2 ntu
  • Residual solids of about 0.3 percent solids

Process Schematic (note that UV disinfection and filtration modules were not used during SFBW pilot testing; schematic provided by Siemens Water Technologies, September 2007)

Process Flow Schematic (Provided by Siemens Water Technologies, September 2007)

View Typical System Drawings (Provided by Siemens Water Technologies, September 2007)