The GritCup® is an efficient and economical all-hydraulic grit washing and classification device, which produces clean grit ready for dewatering by a SpiraSnail® dewatering system. Effectively separating and classifying 95% of all particles 106 micron and larger and 75% of 75-106 micron particles without the need for washwater, it provides effective, affordable grit washing and classification that is ideal for smaller plants with peak flows of up to 10 MGD.

A fully enclosed system with no power requirements, no moving parts and no washwater requirements, the GritCup® is a low-maintenance, economical, operator-friendly grit washing solution.  


  • Grit washing and classification at smaller wastewater treatment plants
  • Grit washing for plants with no available washwater
  • Treatment plant retrofits
  • Grit washing for advanced grit removal systems such as HeadCell® and Grit King®

Only GritCup®

  • Is optimized for use with the SpiraSnail® grit dewatering system

Designed for

Coarse particles

Fine particles


Get efficient grit washing optimized for smaller plants

Designed to address flows of up to 10 MGD peak, the GritCup® has been optimized for use at smaller plants - meaning that it is able to provide effective, economical grit washing, separation and classification while maintaining the high performance that wastewater treatment plant operators need. 

Minimize operational and maintenance costs

The fully enclosed GritCup® system has no moving parts and no power requirements, and features removable access hatches and maximized internal clearances, making infrequent maintenance tasks quick and easy. The system can run fully automatically, requiring virtually no operator input or in-field adjustment, and the system is optimized for intermittent operation - meaning that you save money by only operating it when you need it. 

Eliminate wear and replacement parts

Replacement parts can rapidly erode a plant's operating budget. The GritCup® is a single self-contained unit with no moving parts, meaning that wear and expensive replacement parts are not a factor.


How it works
  1. Flow enters the GritCup® tangentially, creating a vortex flow pattern. The GritCup® uses a combination of vortex principles to achieve removal and washing performance while maintaining a low headloss.

  2. The GritCup® unit uses accelerated gravity to create a separation zone in which organics are removed from the heavier grit. Grit is retained while the organics are stripped away and exit with the degritted effluent. 

  3. The degritted overflow and organic particles exit at the top of the vessel to be conveyed back into the wastewater stream. All of the collected solids are constantly discharged from the grit pot as concentrated slurry via the tangential underflow pipe.

A Hydro-Brake® flow control device is located on the underflow pipe to regulate the volume of slurry exiting the GritCup®. The flow control uses a tangential inlet to create a vortex with an air core in the center that effectively limits the discharge through the centrally located outlet. This allows metered underflow from the GritCup® without the restriction of a small orifice or pipe run and prevents the associated risk of plugging.

Technical information


  • 95% separation of 106 micron particles and larger
  • 75% separation of 75-106 micron particles


  • 200 gpm

Design notes

  • Standard 304 stainless steel construction (316 SS optional)