Sand traps 

A grit chamber is a mechanical treatment unit designed to separate sand, gravel, and rapidly settling mineral particles from the wastewater flow.

At first glance, sand may appear to be a harmless contaminant.
However, in real operation it becomes the source of many technological problems.

Mineral particles:

accumulate in channels and pipelines

cause wear of pumps and valves

damage mechanical equipment

reduce the efficiency of subsequent treatment stages

For this reason, grit chambers are installed at the initial stage of wastewater treatment plants, where they perform an important protective function — removing abrasive particles before the flow reaches the main technological equipment.

The removal of mineral solids significantly extends the service life of pumps, pipelines, and mechanical components of treatment facilities.

TYPES OF EQUIPMENT

Two main types of grit chambers are commonly used in wastewater treatment systems.

Underground Cylindrical Grit Chambers

These units are mainly used in stormwater treatment systems.
They are installed underground and occupy minimal surface area.

Above-Ground Vertical Grit Chambers

These units have universal application and are widely used in industrial, municipal, and domestic wastewater treatment plants.

Such systems provide convenient maintenance and allow efficient removal of accumulated mineral sediments.

The operation of a grit chamber is based on a simple physical principle — the difference in settling velocities of particles.

When the wastewater flow enters the working chamber, the velocity of the liquid decreases.

As a result, heavy mineral particles begin to settle at the bottom of the tank.

In above-ground grit chambers, the settled sand is collected in a special trough equipped with a screw conveyor.

The screw conveyor performs two main functions:

collecting the accumulated sediment

transporting it to the discharge area

The separated sand is then directed to a collection container for further disposal.

At the same time, the treated flow, freed from mineral particles, is discharged through the upper outlet pipeline and directed to the subsequent stages of treatment.

STRUCTURAL DESIGN

To ensure reliable operation in aggressive environments, grit chamber components are manufactured from corrosion-resistant materials.

The body and screw conveyor are typically made of:

stainless steel

acid-resistant steel

These materials provide excellent resistance to corrosion and mechanical wear.

Underground horizontal grit chambers are usually manufactured from reinforced fiberglass, which offers high structural strength and strong resistance to chemical exposure.

Compact design

Efficient equipment layout allows significant savings in installation space.

Automatic sediment removal

The screw conveyor automatically removes accumulated sand as it forms.

High corrosion resistance

The use of stainless and chemically resistant materials ensures long service life.

Ease of maintenance

The design provides convenient access to main components and minimizes operating costs.

Grit chambers are widely used in various mechanical treatment systems, including:

• preliminary treatment units for industrial wastewater
• stormwater treatment systems
• municipal and domestic wastewater treatment plants
• dedicated sand separation units in technological processes

Due to their design, grit chambers effectively protect treatment plant equipment and ensure stable operation of the entire wastewater treatment system.