The rotary screen is self cleaning and constructed of stainless steel AISI 304.

 

A wedge shaped bar is wound in a spiral form to obtain the screening drum. The broad base of the wedge is at the outside. The slotwidth is therefore the smallest on the outside of the screen. In this way clogging risk of the slots is reduced to a minimum.

 

Water enters the screen at the outside of the drum. Particles larger than the slotwidth are retained on the drum, scraped off and discharged through a gutter.

 

Water flows into the drum from the top and leaves the drum at the bottom. Any remaining particles, after scraping, will be picked up by the water leaving the screen.

 

In the inlet compartment an overflow weir is installed to protect the screen from excessive water flow or to adjust the capacity.

 

A high pressure jet spray is installed in the drum for cleaning. A pipe provided with spray nozzles is installed axially into the drum. An automatic cleaning cycle can be installed in the control panel to activate an electric valve in the water supply to the spray nozzles. In cases with high fat contents in the waste water it is recommended to connect warm water to the spray system.

 

The curved screen is constructed of stainless steel AISI 304 wedge shaped bars, which are installed with spacing equal to the desired slot width for screening. Due to the wedge shape, the slot width is the smallest at the water supply side and as such clogging is minimized since particles can hardly get stuck between the wedges. Only in cases of water with high fat contents a slight risk of clogging exists. In such cases a spray cleaning device is installed to keep the screen clean.

 

The waste water is fed on top of the curved screen and flows downward the spacing between the wedges. Solids larger than the spacing will be retained on the screening surface and will be collected down into whatever collection system is available.

It  proofed to be very suitable for municipal wastewater and wastewater from slaughter-houses, meat- and vegetable processing, food-, leather-, beverage-, chemical industry and at water conditioning plants.

The rake is installed directly in the feeding channel of the water to be treated. Solids settle in front of the screen blocking it. As a consequence the water level in front of the screen will rise. This situation is registered by the level sensor which at this point starts the motor drive of the screen and consequently cleaning of the screen. This way the screening effect is optimized and wear of mechanical part minimized. The screenings are transported from depths to the top of the channel or to a higher level and can be discharged into a container or treated further (washed, compressed etc.).

Its advantage also consists in usability in deep channels and the self cleaning of the filtration band.

 

The PSC/PSC/C-type screen press is a combined machine consisting of the components:

 

 

Screen, tubular trough fabricated parts in stainless steel 304

Screw flighting in special high resistance steel ST52

 

Solids settle in front of the screen blocking the mesh. As a consequence the water level in front of the screen will rise. This situation is registered by the level sensor which at this point starts auger rotation and consequently cleaning of the screen automatically. Solids are now conveyed and compacted (PSC/C) and then ejected through the outlet. An adjustable timer will stop the machine after the preset time.

This way the screening effect is optimized and the wear of mechanical parts minimized.