Internal feed screen.
A fine screen for the inlet of a treatment plant: the flow is fed to the inside of the mesh panel belt, the screenings stay on the inner face, and the wash system carries them out to the discharge instead of back into the channel.
How the internal feed screen works
The mesh panels are carried on a frame that sits in the inlet channel, and the flow is fed to the inside of the belt rather than to the outside. Water passes outwards through the panels, so everything larger than the aperture is held on the inner face, and the panels are washed on their return path: the wash system flushes the captured material into a discharge chute or a conveyor, and the panels go back to the channel clean. Feeding from the inside is what keeps the screenings out of the flow on the way back — the material cannot be dragged down the channel by the downstream face of the belt. The belt runs slowly and continuously, so the screen takes a flow that varies through the day without an operator in attendance, and the drive and the wash water supply are the only services it needs.
Channel-mounted internal feed screen
The screen is built as a fabricated channel section that is cast into or bolted onto the inlet structure. The casing carries the inlet and outlet connections, hinged covers over the panel run, and an inclined screw conveyor that lifts the washed screenings clear of the channel to the discharge point. The drive is mounted above the covers, clear of the water, so the panel run and the wash system can be inspected from the walkway without dewatering the channel.
Vertical internal feed screen
In an inlet chamber rather than a straight channel, the same screen is built as a vertical unit: the drive and the discharge sit on the head frame and the panel run hangs below it into the water. The assembly is lowered into the chamber as one piece, which suits a retrofit where the inlet structure already exists and the screen has to fit the space that is there.
Applications
Municipal pretreatment and headworks
The inlet duty of a municipal plant, where the fine screen takes out the material that would otherwise reach the grit removal stage, the pumps and the process units downstream.
Industrial inlet screening
The same duty at the front of an industrial treatment train, where the incoming wastewater carries process solids, fibres and packaging debris.
Protection of downstream units
Fine screening ahead of a membrane, filtration or dosing stage, where the equipment that follows cannot tolerate fibrous material and has to be protected from it.
Delivery
Units are assembled and tested at our factory before shipment, then shipped with export documentation. The channel or chamber dimensions and the discharge arrangement are confirmed against the site before the build. Loading arrangement and delivery schedule: [to be confirmed with factory].
