- Frame in AISI 304/316 stainless steel, depending on requirements
- Shaftless spiral in high tensile carbon steel or AISI 304/316, depending on requirements
- Flow rate up to 650 m³/h (180 l/sec.)
- Screen aperture from 3 to 7 mm (perforated plate)
- Screen diameter from 300 mm to 700 mm
- Extracted solids volume reduction of up to 30%
- Screenings washing system to reduce organic matter contents
- Insulation and heating for installation in very cold climates
- Extracted solids collection system: in single bags or continuous liner
- Manual system for disconnecting the screen from the deck (screen hoisting with crane)
- Starting from standard dimensions, the machine can be supplied in customized lengths in accordance with the screening and transport section
- Municipal or industrial: wastewater screening in pipes, in pumping pits and deep pits (up to 10 metres)
- Low investment profile
- Reduced maintenance due to the absence of screw end bearings and intermediate hangers
- No mechanical components in contact with the product
- Reduced rotation speed
- Shaftless spiral: no risk of jamming and/or clogging, even when handling fibrous products
- Extracted solids volume reduction of up to 30% and more, depending on the product (models with compaction only)
Description and operation
The Definitive Ecology vertical screw screen is a combined machine for screening, lifting and compacting suspended solids in wastewater, in pits up to 10 metres deep. The vertical screw screen is generally used for screening in pumping pits, to prevent suspended solids from reaching the pump. The machine is composed of a perforated plate with aperture from 3 mm to 7 mm, and a screw conveyor to lift the solids separated from the wastewater and transport them to the compacting basket. The machine can be combined with a compactor module to dewater the solids, thus reducing the volume by up to 30%, depending on the type of solid contents.
The wastewater inlet can be via an open or closed screen basket solution. The closed screen basket model makes it possible to connect to the inlet pipe by means of a flange or a specific accessory device that allows manual disconnection of the machine while the operator remains on the deck outside the pit. The closed screen basket solution also features a bypass so it can handle sudden changes in flow rate.
Optional washing stages can be combined in the screening and transport zones to reduce the contents of organic matter in the screenings.
In screen models with compaction, washing of the screened material is supplied as standard and the resulting effluent is discharged downstream of the screen.
Operating principle: with the passage of wastewater through the screen, solids of dimensions greater than the required aperture / spacing are intercepted, thus binding the screen and causing a rise in the liquid level in the pit.
Once a pre-determined level is reached upstream from the screen, the screenings screw conveyor is started.
Brushes, installed on the outer edges of the spiral, make it possible to clean the screen and hence restore the passage of wastewater through the screen, consequently lowering the water level in the pit until reaching the minimum level probe which will stop the screw.
SF/V = screw screen for vertical pit installation
SFC/V = screw screen for vertical pit installation, with compaction