From Water Intake Systems
A Hubert vertical drum screen is the ‘heart’ of the ‘screening train’. A (vertical) rotary drum screen is mainly used used for (sea)water intakes as part of power plants and desalination plants, where tidal differences can also play a role. More information about applications can be found here. A drum screen is typically installed in water intake systems downstream from coarse bar screens. Regularly occurring flow rates are between 40.000 and 120.000 m3/h per screen, depending on customer requirements and the local situation at the intake. Woven mesh with a diameter of about 2-3 mm is used as filter medium.
A vertical drum screen is used for mechanically clean or screen water extracted from the sea, rivers or lakes. Mechanical cleaning removes entrained (floating) matter with screens or sieves. This protects the downstream process stages from buildup, clogging and abrasion. The aim is to protect suction pumps and other downstream equipment such as desalination membranes, heat exchangers/ condenser tubes or from the carry-over of coarse and fine debris.
Hubert supplies its own designs where possible, however all systems are engineered as per your project specifications. If you prefer a different design, we can of course also supply this. We are happy to advise you to make the best choice for your project. When renovating existing installations (which have been in operation for many years), dated designs are often used or, if possible, the civil construction is adapted to a modern design.
This movie gives an impression of a vertical drum screen during assembly.
Design, Construction & Operation
The drum is placed in a concrete pit or tanks and rotates on a stationary hollow shaft. The water to be filtered flows through the drum panels and the dirt particles remain trapped in the mesh. Hubert vertical drum screens are available for different flow patterns see further on this page, or see page Flow Patterns Drum Screen for a comparison between different flow patterns. As the drum rotates the row of sceen panels pass under or above a set of high pressure water jets at the top of the drum. The dirt particles are washed from the screen and discharged through a debris collector system. The Hubert vertical (rotary) drum screens are designed with A-shaped spokes, resulting in high rigidity and resistance to deformation. This produces an accurate fit against pit walls, enabling filtration of particles down to 2 mm. All Hubert drum screens are fitted with maintenance free slide (sea)water lubricated bearings. The same applies to the ring gear and drive pinion, which are made of special wear resistant polyamide.
Vertical Drumscreen – Flow Patterns
Hubert supplies both ‘Dual Flow’ and ‘Center Flow’ patterns. A ‘Dual Flow’ configuration has some advantages against ‘Center Flow’. In case of a newly built plant, Hubert advises the ‘Dual Flow’ pattern. More information about the differences and a comparison in flow patterns can be found on page Flow Patterns Drum Screen .
Fish Friendly - Fish recovery system
Hubert’s drum screens can be supplied with a fish recovery gutter or channel that allows trapped fish to be removed in a gentle and effective way. These recovery systems are tailor-made for each project.
Features & Benefits
- Large flow capacities
- The A-spoke construction results in a light stable and rigid structure
- Maintenance free
- Long lifetime (30 years or more)
- Resistant to abrasive water
- Debris is removed at or above deck level, eliminating the need for a debris pump
- Savings on spare parts
- (Sea)water lubricated bearing
- Spray water cleaning
- Fish removal system
Standard Dimensions & Materials
- Drum width up to 5 m
- Drum diameter up to 20 m
- Mesh opening 2/ 10 mm
- Materials can be coated carbon steel, stainless steel and exotic alloys (a variety of (super) Duplex grades)