Contact

E. BEAUDREY ET CIE.

Tel. +33 1 42 57 14 35

beaudrey@beaudrey.com

BEAUDREY AMERICAN SERVICES

Tel. +1 970 237 2578 / +1 970 286 1953

beaudreyas@beaudreyas.com

BEAUDREY ASIA SDN BHD

Tel. +60 3 2284 1912

beaudreyasia@beaudreyasia.com.my

©2018 by Beaudrey

TRAVELLING BAND SCREENS
CENTRE-FLOW FROM INSIDE TO OUTSIDE

PURPOSE AND APPLICATION

Travelling screens are used to arrest the small debris contained in the water so that the downstream users remain unobstructed and clean (condensers, exchanges, spray-water circuits, membranes etc). Debris can be of all types including fish, shrimps, jellyfish, grass, man-made refuse, plastics, seaweed, etc. They are especially suited to deep pits.

 

They are used in thermal and nuclear power plants, LNG terminals, desalination or fertilizer plants, drinking water, sewage and irrigation plants.

DESCRIPTION

Installed in a channel in which the water to be cleaned flows, the screen consists of a set of rectangular screening mesh panels carried by two endless chains. The panels travel up and down again between an upstream partition set across the channel, with an inlet central aperture and a downstream wall set across the channel. The water enters through the aperture in the upstream partition, flows through the upstream face of the panels on each side, where the debris are arrested. The water flows out through the apertures on both sides of the downstream wall-plate.

 

The debris-laden panels travel up above deck level, around the top and down again. One or two spray pipes with fantail jet nozzles set on the down stream side of the panels within the screen’s head structure, back-wash the panels, remove the debris which are projected into a collection trough. They travel in a deck flume to the debris disposal system (basket, separator, etc.)

 

The screens are normally stopped and are washed periodically when obstructed by debris. Permanent rotation can be provided.

Center-flow Travelling Band Screen Hydraulics

ADVANTAGES

  • Large debris-handling capacity

  • Compact civil structure

  • Fully automatic

  • Capable of high-speed rotation

  • Fish-friendly option

  • Reduced maintenance

  • Cost effective

  • No debris carry-over

  • Easy access to external debris trough

  • No internal debris interference

NECESSARY ANCILLARIES

  • Spray-water supply circuit

  • Head-loss monitoring system

  • Electrical control cabinet

  • Upstream bar rack (25 to 75 mm spacing (1 to 3”)

  • Pit dewatering stoplogs

  • Trash collecting system (basket, etc).

SIZES AND DATA

  • Mesh aperture     
    From 1x1 to 10x10 mm (0.04 to 3/8”)     

  • Flow rates
    Up to 70000 m3/h (300000 gpm)

  • Tidal variation      
    No practical limit  

  • Panel frame useful width
    0.6 to 4 m (2 to 13 ft)      
    Wider machines on special order

OPTIONAL FEATURES

  • Two or three-speed operation

  • Seismic qualification

  • Special high travel speed design for handling heavy debris loads

  • Jellyfish lifting trays

  • Screening medium resistant to fiber build-up

  • Screening medium preventing jellyfish adherence

  • Low pressure water-life protection system

  • Atex compliance

  • “Scoop-a-fishTM” total fish survival system

  • Wall-mounted chain guides on full carrying structure

  • By-pass valves

MATERIALS

  • Main structure, panels, frames, guide rails        
    For fresh-water applications: painted carbon steel or AISI 304L stainless steel     
    For seawater applications: AISI 316L stainless stee, duplex or super-duplex stainless steel      

     

  • Head-shaft, sprockets, chain links and pins, tensioning capstan screws     
    For fresh-water applications: High-tensile steel 
    For seawater applications: Duplex or super-duplex stainless steel      

     

  • Bolts, nuts, washers        
    For fresh-water applications: A2 or A4 stainless steel  
    For seawater application: A4, duplex or super-duplex stainless steel  

     

  • Small fittings, spray-water pipes
    For fresh-water applications: AISI 304L stainless steel
    For seawater applications: AISI 316L, duplex or super-duplex stainless steel     

     

  • Screening mesh frames, sprocket teeth
    In all cases: composite materials

     

  • Covers     
    GRP or stainless steel on special request

     

  • Anodes    
    None required for fresh-water applications        
    For seawater applications: required for use with AISI 316L stainless steel and sometimes for duplex stainless steel.

CENTER-FLOW BAND SCREEN - BROCHURE

CENTER-FLOW BAND SCREEN - DATA REQUIRED TO QUOTE