OpTeaCup - Optimized Grit Washing System
Water and wastewater treatment

Industry leading grit concentration and classification – now with expanded clearances to prevent ragging and clogging.

The OpTeaCup™ is the next generation of TeaCup® grit concentration and classification. Based on Hydro International’s 40+ years of experience with industry leading grit washing systems, the OpTeaCup™ was developed to address the needs of modern wastewater treatment plants. Significantly expanded clearances prevent clogging from nuisance materials like flushable wipes and rags. Internal components have been minimized and streamlined to further increase throughput capabilities without reducing fine particle capture performance.

The improved geometry eliminates the need for fluidizing water, actuated valves, or solenoids - reducing utility requirements and maintenance needs. An improved and easily accessible / replaceable orifice plate simplifies long-term maintenance and ensures a very long product life.

The OpTeaCup™ is a durable, flexible, grit concentration / classification solution that will ensure that your grit removal process will protect your plant under all operating conditions.

The OpTeaCup™ is a high-performance accelerated gravity grit removal, separation, and classification system. The OpTeaCup™ is an evolution of Hydro International’s TeaCup® that has set the standard for high-performance headworks grit management for over four decades. OpTeaCup™ is optimized for grit collection, grit concentration / classification, sediment removal on pumped flows and for both continuous or intermittent operation. The OpTeaCup™ addresses both municipal and industrial solids grit removal challenges.

The OpTeaCup™ removes 95% of wastewater abrasives 75 micron and larger to cut deposition and reduce mechanical wear. OpTeaCup™ reduces maintenance and repair of downstream processes and can reduce solids handling costs by as much as 50%. 


  • Grit removal, concentration, and classification at WWTP headworks
  • Snail shell removal from trickling filters
  • Grit system replacement and upgrades 
  • Sediment removal and pretreatment of potable water

Designed to pass pretty much everything but grit

With no moving parts or fluidizing water, there’s fewer components to maintain. Significantly expanded clearances, with a clear 4” (100 mm) opening from top to bottom, prevent even the most stubborn nuisance materials like rags, strings, and plastic from getting caught in the system. Low profile fasters have been introduced which streamline the internals, further reducing plugging potential. The revised geometry of the OpTeaCup™ eliminates the need for a baffle plate, another potential pinch point for clogging.

Engineered for easy maintenance and enhanced durability

While the expanded clearances significantly reduce treatment plant operators' maintenance burden, the OpTeaCup™ doesn’t stop there. Strategically placed access hatches allow quick and easy access to every part of the OpTeaCup™ system, while a new poly-coated replaceable orifice plate has been added that is easy to remove and install, significantly reducing the time and cost of major long-term maintenance.

Reduce footprint and save money on electricity

The compact design of the OpTeaCup™ requires up to 80% less footprint than conventional grit concentration / classification systems, which frees up valuable plant space for other processes. The all-hydraulic OpTeaCup™ requires no fluidizing water, solenoids, or additional electricity to provide phenomenal grit removal performance. 

Reduce downstream wear and maintenance 

With guaranteed performance and removal rates of up to 95% of wastewater abrasives you can be confident that the OpTeaCup™ will reduce downstream deposition and significantly reduce excessive mechanical wear - cutting annual maintenance and repair costs. 

Increase processing capacity of all your downstream equipment 

Without the protection of a Hydro International Advanced Grit Management® system, grit accumulates in downstream processes and these processes serve as grit storage - clogging them and significantly decreasing their processing capacity. Additionally, excess capacity needs to be available to take various processes offline and manually remove uncaptured grit that has deposited. With the OpTeaCup™ you cut out the grit upstream, reducing downstream accumulation and reducing the need to pay for expensive process capacity to store your grit. 

Flexible after installation to manage organics  

For plant operations where coarse organics (such as corn) are beneficial to downstream bioprocesses, a smaller diameter orifice place and vortex finder can be provided which will allow more coarse organics to pass through the grit removal process to be utilized downstream. The smaller orifice plate can be provided at initial installation but can also be installed post-installation and is interchangeable with the larger versions. This allows plants to future proof their grit removal process if their organics retention needs change in the future.

Flow enters the stainless-steel vessel tangentially at a controlled rate and velocity. The flow regime established in the device forms a free vortex which results in high centrifugal forces and a thin predictable boundary layer. Grit is forced to the outside perimeter or held in suspension until it falls by gravity into the boundary layer which sweeps the grit into the collection chamber at the bottom of the unit. Volatile solids are lifted from the bottom of the unit and ejected out the system overflow and returned to the WWTP for treatment. 

The OpTeaCup™ uses a combination of a free vortex and the accelerated gravity boundary layer effect to capture, classify, and remove fine grit, sugar sand, and high-density fixed solids. The OpTeaCup™ discharges concentrated grit slurry to the Grit Snail® for dewatering.

  1. Flow enters the stainless-steel vessel tangentially at a controlled rate and velocity.
  2. The flow regime established in the device forms a vortex, which results in high centrifugal forces and a thin, predictable boundary layer.
  3. Grit is forced to the outside perimeter or held in suspension until it falls by gravity into the boundary layer, which sweeps the grit into the collection chamber at the bottom of the unit.
  4. Volatile solids are lifted from the bottom of the unit and ejected out the system overflow and returned to the WWTP for treatment. 
  5. The concentrated grit slurry leaves the bottom of the unit.  
  6. Periodically, flow to the system is paused to allow the vessel to drain down and pass any large solids that might have stalled within the system.

Watch this Video to see a demonstration of the throughput capacity of OpTeaCup™ and how well it handles rags

OpTeaCup Cutaway Image

Performance characteristics

Removal rate

  • Removes 95% of grit particles 75 micron and larger at the design flow rate


  • Outputs less than 20% Volatile Solids when sufficient fixed solids are present in wastewater influent


  • Handles flows between 200 to 400 gpm (13-24 L/s) 
  • Solids concentrations up to 1.5%

Unit size

  • Single unit diameter is 32” (0.8 m) diameter

Design notes

  • Open free vortex design 
  • Simple operation, long product life
  • Large diameter easily handles peak flow volumes without clogging
  • Prefabricated modular components provide simple installation and maintenance 
  • Discharges a clean grit slurry, with low volatile solids 
  • Suitable for batch processing or continuous operation 

  • OpTeaCup - Optimized Grit Washing System
  • Replaceable poly-coated orofoce makes long term maintenance a breeze!
  • Cutaway view of OpTeaCup Internals
  • OpTeaCup on Grit Snail dewatering
  • Two OpTeaCup Grit Snail Sysytems
  • Orifice plate prior to install
  • OpTeaCup Close view
  • OpTeaCup on Grit Snail

Can the replaceable wear plate be serviced by our plant staff, or does it require a Hydro International Technician?


Either way. The procedure is designed to be simple and detailed instructions are provided in the O&M manual, but Hydro does have field staff standing ready to perform this task if you would rather have us do it. 


Are additional sizes available to handle larger flows?


The OpTeaCup™ is currently available in a 32" (0.8 m) diameter system that can accommodate flows of 200-400 gpm (12.6-25.2 L/s). Two OpTeaCup™ systems can be provided on a single Grit Snail® to double that flow capacity. 


We have extreme ragging issues at our plant, can the central internal clearance be larger than 4"?


Yes. In situations like this, the OpTeaCup™ can be provided with a 6" (15.2 cm) diameter central internal clearance. 


What types of grit dewatering systems can be used with the OpTeaCup?


The OpTeaCup™ can either be paired with a high performance Grit Snail® dewatering escalator or a SpiraSnail® Compact dewatering classifier from Hydro International.

Parts & Spares

Keep your Hydro International water management systems running effectively and efficiently. Our services teams will supply you with…

OpTeaCup vs. TeaCup

Learn more about the design improvements built into the OpTeaCup™ and how it compares to TeaCup® technology. 

  • HeadCell

    Industrial water treatment

    Remove more, finer grit to protect downstream equipment, increase plant efficiency and cut maintenance and repair costs. The HeadCell®…


Join our mailing list

We'll keep you updated about things like news articles, upcoming webinars and product developments.