Catalogue

Plants, equipment and machines for water treatment

ESC

The screw sand classifier integrating the Coanda effect is designed for the installation in sewage and wastewater treatment plants of medium to large and very large size. It is mainly applied to work together with sand traps, to obtain a high dewatering rate of the discharge sands resulting in a water content, besides an organic content, that is usually approximately 90÷95%.
It is essentially composed of: 
- a trunk conical tank; 
- a specially formed screw inclined at 30° or 45°; 
- a motorized valve for the organic matter discharge; 
- a completely automatic sand washing system composed of rotameter, for flow measurement and valves and solenoid valves for regulating the water flow; 
- a sensor for the sand density measurement; 
- a bottom drainage system; 
- a sturdy gearmotor suitable for the rotation of the screw; 
- a sand discharge hopper; 
- suitable supports and anchor bolts to ensure good stability.
Sand mixed with water and organic substances comes in the sand classifier ESC by the upper central part of the tank, through a tangential inlet with cyclone that guarantees separation by Coanda effect. The design of this upper part is oriented to have immediately the separation of sands heavier than water.
Sand washing water is injected in the tank bottom to guarantee a good sand washing and to separate the organic content. In this way, water and organic substances come out the tank respectively by a special overflow and a motorized valve, while the sand settles in a section of the bottom.
Settled sand is kept and lifted by means of the rotating screw, suitable for a maximum drainage of water, and then it is discharged through a pipe into a disposal device.
The protection against overloads is ensured by an electronic load limiting device.
The construction simplicity of the equipment and the quality of all its components always guarantee high performance and reliability, also for continuous working.
The standard construction is in stainless steel, but on request it’s possible the construction in carbon steel protected by an epoxy painted cycle after a treatment with inorganic primer.

Strengths

• USE THE COANDA EFFECT FOR A HIGHER PERFORMANCE OF THE UNIT.
• SCREW INSTALLATION SLOPE AND SIZE CAN VARY ACCORDING TO THE APPLICATION.
• SIMPLE AND RELIABLE.
• FLEXIBLE APPLICATION WITH ANY TIPE OF SAND TRAP AND DISPOSAL DEVICE.