A screen for sewage treatment plants just the way you want it
Effective & economical
A brilliant result in every respect: a nrw contec screen reliably removes floating matter, sediment, suspended matter and fibrous matter. Extremely low-maintenance, it also requires little cleaning water and energy.
Numerous wastewater treatment plant operators and industrial companies trust the stable, long-lasting contec screen.
Permanently working
- High degree of separation of screenings
- Low space requirement
- Little cleaning water
- Extremely low maintenance
- Designed for high durability
- Economical thanks to low drive power.
- Low-wear
Cleaner & conditioner
Areas of application wastewater treatment plant
- Mechanical wastewater treatment
- Pre-cleaning for membrane sewage treatment plants
Fields of application
- Industrial waste water treatment
- Treatment of process or cooling water
Function: simple
- The waste water reaches the semicircular perforated screen plate, which retains screenings.
- The screenings are conveyed by brushes into the lateral screenings discharge.
- The cleaned water flows freely downwards from the perforated screen.
- A simple process for an exceptionally high degree of separation.
The sewage screen for screenings from 0.8 to 16 mm
Screenings 0.8 to 2 mm
Examples: Lint, hair, wool, fine paper fibers, short fibers, and other fine solids.
Screenings 2 to 4 mm
Examples: Bristles, hair, paper, long fibers, cotton swabs, and other solids.
Screenings 4 to 16 mm
Examples: Stones, cans, crown caps, long solids, plastic bags and other coarse materials.
Wastewater treatment with the right sieve size
Ultra-fine screens
Opening 0.8 mm – 2.0 mm
Ultra-fine screens for the effective protection of membrane wastewater treatment plants or particularly sensitive process wastewater treatment plants.
Fine screen
Opening 2.0 mm – 4.0 mm
Conventional municipal or industrial wastewater treatment plant, contaminant removal and to protect downstream equipment.
Coarse screen
Opening 4 mm – 16 mm
Coarse screens for coarse material separation in industry, waste water from vacuum trucks, slaughterhouse, 1st cleaning stage in waste oil treatment, washing plants for military vehicles.
The screen of the wastewater treatment plant: 1st point of contact for screenings in wastewater
Screenings are the substances retained by a screen or sieve in a screening plant or waste water treatment plant.
Screenings consist primarily of organic substances and mineral components. Unfortunately, there are always contaminants in the wastewater for which actually a different way of disposal is supposed. For example, hygiene articles or small packaging.
The nature and the proportion of the usually foul-smelling screenings are important parameters for professional planning and the design of an efficient screening plant. For example, at the sewage treatment plant.
The nrw contec screen: With throughputs of
up to 3,600 m³/h an ideal screen for screening plants or waste water treatment plants.
A good piece of mechanical waste water treatment
The screen in a wastewater treatment plant usually represents the first purification stage. Here the coarse components, the so-called screenings, are filtered out. The geometry of the opening determines what the screen filters out. At the same time, the screen protects downstream treatment stages – for example membrane treatment plants – from coarser sediment, floating, suspended and other impurities. In terms of the process, the screen represents a part of the mechanical wastewater treatment in the wastewater treatment plant.
Waste water simply cleaned well:
The nrw contec screen
Based on the only low flow velocity and its generously designed screen surface, a nrw contec screen offers particularly good solids retention.
There is no need for a separate or particularly time-consuming cleaning process: during screening, the nrw contec screen virtually cleans itself all the time.
For increased demands on solids retention, a screen is the right choice. Also in smaller rooms.
Areas of application of the nrw contec screen
Mechanical pre-cleaning
For screening out disposable products (impurities) in municipal wastewater.
Examples:
- Raw sewage
- Clarification
- Small sewage treatment plants
- Direct discharge
- Sedimentation tank
- Sludge screening
- Rain overflows
Membrane pre-cleaning
For the pre-treatment of waste water before membrane plants (MBR / membrane bioreactors). Or so that MBR plants are not damaged. The use of the nrw contec combination screen is also possible here.
Examples:
- Untreated raw sewage
- Pretreated waste water
Industrial applications
For the pre-cleaning of industrial water.
Examples:
- For mechanical pre-treatment of industrial waste water before discharge into the receiving water or into the plant’s own waste water treatment plant.
- For the treatment of industrial process or cooling water for reuse.
- Removal of contaminants to protect downstream equipment.
- Separation of valuable materials in the recycling industry.
Basic equipment of the nrw contec screening system:
Sophisticated, robust and durable
nrw contec screen with explosion-proof motors in tough use
RBS twin combi screen system in special design for the chemical industry
Drive: Made in Germany
The brush cross in a nrw contec screen copes very well with only approx. 2 rpm. Driven by energy-efficient and highly reliable gear motors made in Germany.
Variable: Cleaning brushes
The polypropylene brushes used in the screen achieve a service life of several years. Due to their length and arrangement, they are extremely resistant even to abrasive Screenings.
To compensate for wear, you can simply readjust the brushes. In normal operation, the brushes achieve service lives of several years.
Safe: Cover
Smaller systems are equipped with a hood.
Larger units have a hood, door and protective grille.
Options for the nrw contec screening system
screen with emergency overflow pipe
Lower tub with two drains
Infeed
The Infeed of the nrw contec screening system is located on a front side. In the standard system you can choose
- from Infeed different sizes according to DIN or ANSI standard,
- from special constructions according to your requirements.
Outlet
Every drain installation is different. nrw contec screening systems adapt.
How the purified water runs
- freely downwards into a tank/ container,
- via an open channel into downstream plant components,
- into a catch basin with connected piping to downstream plant components.
Screen perforation
Select the screen that matches the screenings ...
- Ultra-fine screen: opening 0.8 - 2 mm
- Fine screen: opening 2 - 4 mm
- Coarse screen: opening 4 - 16 mm
Material
- Stainless steel 1.4301
- Stainless steel 1.4571
- Special materials, for example 1.4462 Duplex (extremely corrosion-resistant)
Emergency overflow
If, for any reason, a nrw contec screen should experience a hydraulic overload, it is protected by
- an overflow pipe.
For example, if the screen is installed to protect an MBR system.
- a box as a bypass.
An overflow that allows wastewater to pass through the screen untreated in the event of an overload.
Accessories for the nrw contec screening system
screen with screenings chute
Screen with integrated screenings press
Discharge via screening chute
The simplest ejection solution.
Via the screenings chute, the solids are discharged directly into a container.
The chute in the form of a flat channel can be open, covered or equipped with heating.
Discharge via screenings conveyor
For the removal of separated screenings.
A screenings conveyor (spiral conveyor / screw conveyor) installed at the screenings discharge conveys the screenings horizontally/sideways.
Screenings press discharge
For weight and volume reduction of the screenings.
The screenings press is installed directly at the screenings discharge.
The screenings press or "screw press" conveys the separated screenings laterally into the pressing zone by means of an integrated screw conveyor. A counterpressure is generated in the pressing zone. In this way, the soft, waterlogged screenings are wrung out and compacted.
While the water drains off through a perforated screen in the pressing zone, the pressed screenings push out like a sausage.
Discharge via a screenings washing press
For the removal of still adhering faecal residues.
Similar to the screenings press, the screenings washing press is installed directly on the nrw contec screen. Or it is at the end of a screenings conveyor.
The screenings washing press also presses the water out of the screenings. In addition, however, it washes out the screenings. This is done via forward and reverse rotations, while wash water is injected via additional solenoid valves.
This washes away most of the adhering fecal matter. And flow back via a pipeline into the inlet shaft through which the screen is fed.
Sagging devices
For hygienic collection and storage of the separated screenings.
Undesirable: Odour nuisance due to unpleasant smells or vermin "hatching" in the screenings.
A sagging device provides a remedy here. This also discourages animals from searching for food in screenings and spreading it over a large area.
Heating system
For winter operation
Controlled heating system for winter operation in various heating capacities.
Drainage sump
With outlet flange according to DIN or ANSI.
Cleaning system
For cleaning the back of the perforated screen plates.
Elevation
Underframes for adaptation to special installation conditions.
Warning system
Detection via sensor in emergency overflow.
Screenings container
Container with or without drainage.
Exhaust pipe
With flange according to DIN/ANSI for the extraction of unpleasant odours.
Electrical controls
Control incl. safety devices as standard or according to your specification.
Lubrication equipment
Manual or automatic lubrication devices for the shaft bearings.
For waste water flow rates from 2.5 to 3,600 m³/h
nrw contec screen
Suitable for low flow rates – for example for small wastewater treatment plants or small mobile test plants – up to large wastewater treatment plants for wastewater treatment.
Sieving: 1-fold
Flow rate: 2.5 to 3,600 m³/h
nrw contec combination screen
Screening system with 2 cleaning stages connected in series. One drive for coarse and fine screening.
Sieving: 2-fold
Flow rate: up to 80 m³/h