Crossflow Grit Detritor

Product name

Crossflow Grit Detritor

System components

Grit separators

Crossflow Grit Detritor & Rake Classifier by Tuke and Bell Ltd is a grit removal system for wastewater treatment, designed to separate and collect grit and organic matter. System uses a rotary scraper in a collection tank and a reciprocating rake mechanism in a sloping channel. Scraper blades have replaceable, height-adjustable wear tips. All bearings and drives are rated for 100,000-hour design life.

Influent first enters the collection tank through baffles to slow down the flow and assist grit settlement. The tank is capable of handling a wide range of flow variation.

A rotary scraping mechanism, driven from the centre of the tank, moves settled grit through a discharge point located at the side of the collection tank.

From here the grit is discharged to a grit classifier system by means of gravity or by pumping.

The Tuke & Bell Crossflow Grit Detritor incorporates the following features: –

Grit removal system for wastewater treatment using rotary and reciprocating mechanisms
Heavy duty slewing ring supports scraper load with no extra load on gearbox bearings
Direct coupled drive allows easy removal and reduces maintenance
Scraper blades have replaceable, invertible wear tips for longer life
Rake Classifier uses a lightweight space frame to reduce drive loads
All pivot bearings in the Rake Classifier are maintenance free
Fully enclosed mesh panel guards allow instant inspection and access

Rake Classifier

The Tuke & Bell Rake Classifier is a multiple-rake reciprocating mechanism, mounted within a cleaning channel, which is a narrow, continuously sloping ramp.

The reciprocating action moves the grit, up the ramp towards a discharge point above top water level. At this point the grit is free of water, which assists easy and efficient disposal, and free of organic matter caused by the washing action of the reciprocating rakes.

A pumping unit is located within the organics return chamber which induces a current of liquid to flow from the collecting tank through the cleaning channel and back into the collecting tank. For free-standing Rake Classifier units, a wash water pipe connection is included for cleaning of the grit.

Organic matter originally settled with the grit and freed during the washing process is diverted back to the sewage flow for further treatment.

The Tuke & Bell Rake Classifier incorporates the following features: –

Lightweight space frame design to reduce drive loads.
Single sided crank allows for simple drive removal.
All pivot bearings are 100% maintenance free – No lubrication required.
Heavy duty, replaceable ‘Big end’ crank bearing lubricated by single point grease canister or local grease line.
Fully enclosed mesh panel guards allow instant inspection of the rake. Drive is accessible through full size, locked double doors.
25-year design life.

Typically, the Rake Classifier is used in conjunction with a Crossflow type Grit Detritor and together carries out the complete grit extraction process within a compact area. The system can be located either above or below ground level. The Rake Classifier is available as a design suitable for a civil or steel chamber construction.