Devices for Mechanical Wastewater Treatment

Fine Screens and Micro Strainers

Screw Conveyors and Separators

Fine Screen

Micro Strainer with Screw Conveyor

Sand Removal Unit

Unit for Mechanical Treatment of Wastewater

Fine Screens and Micro Strainers

One of the main problems in sewage treatment is the separation of solids from sewage and industrial wastewater. These solids are made up of personal hygiene product wastes, pieces of plastic, cork, fibres, rags, films, household and other wastes. The solids must be removed from wastewater at the beginning of the treatment process in order to avoid clogging of pipes and fittings, hindering of aeration or fouling of overflow edges. For the separation of these solids fine screens and micro strainers with screw conveyors can be supplied. These devices fulfill several functions:

Mechanical separation of solids (screening) from wastewater.
Washing of screenings.
Conveyance of screenings.
Compaction of screenings.

Features

Automatic operation - no need for continuous supervision.
Cyclic operation - little wear.
Washing of screenings - foul odours are eliminated.
Compaction of screenings - to 60% initial volume.
High operating efficiency and low operating cost.
Made completely of stainless steel - reduced corrosion.
Self cleaning.
Wear resistant to sand, gravel and stones.
Readily assembled in rectangular section channels.

Screw Conveyors and Separators

Apart from the solids mentioned above, municipal sewage and industrial wastewaters contain sand, which has to be removed at the initial stages of treatment process. Otherwise sand will cause problems during subsequent stages of wastewater treatment, such as clogging of pipes and fittings, hindering of aeration and premature wear of fittings. Screw conveyors and separators can be supplied. These devices fulfill several functions:

Horizontal transport of sand to collector funnel of a sand trap.
Separation of sand from wastewater.
Vertical transport and dewatering of sand.

Features

Automatic operation - no need for continuous supervision.
Cyclic operation - little wear.
De-watering of sand during its vertical transport.
High operating efficiency and low operating cost.
Made completely of stainless steel - reduced corrosion.

Fine Screens

This device is designed for preliminary removal of coarse solids flowing into wastewater treatment plant. It consists of the following units:

Filter basket with rotary rake for cleaning slots.
Screw conveyor with varying pitch.
Drive unit.
Washing unit.
Control panel.

Technical data

Channel width = basket diameter: 600mm-800mm
Slot size: 7mm or 10mm
Power input: 1.5kW
Capacity: 60-670 l/s
Control: Automatic
Construction material: Stainless steel

Operating principle

Coarse solids with wastewater accumulate in the slots in the filter basket. The rotary rake scrapes the screenings into the screw conveyor trough. The screenings are washed, de-watered and compacted within the conveyor. De-watered and pressed screenings are transferred to a container. The screw conveyor may be equipped with a heating jacket. The diameter of the screen is determined from a flow versus slot size chart, other dimensions subject to agreement.

Micro Strainer with Screw Conveyor

This device is designed for preliminary treatment of wastewater, especially in small treatment plants. It consists of the following units:

Filter strainer with screw scraper.
Screw conveyor with varying pitch.
Drive unit.
Washing unit.
Control panel.

Technical data

Channel width: 300mm-600mm
Filter slot size: 1mm-10mm diameter
Power input: 1.5kW
Output: 20-72 l/s
Control: Automatic
Construction material: Stainless steel

Operating principle

Coarse solids flowing with wastewater accumulate on the filter screen. Screw scraper with cleaning brushes transfers the screenings from the screen to the screw conveyor. The screenings are washed, de-watered and compacted within the conveyor. De-watered and pressed screenings are transferred to a container. The screw conveyor may be equipped with a heating jacket. The diameter of the screen is determined from a flow versus screen mesh diameter chart, other dimensions subject to agreement.

Sand Removal Unit

This device is designed to remove sand from the trough of a sand trap in a wastewater treatment plant. It consists of the following units:

Horizontal screw conveyor at the bottom of the sand trap.
Inclined screw conveyor in the collector funnel of the sand trap (separator).
Control panel.

Technical data

Channel width: 600mm-1800mm
Power input: 3kW
Control: Automatic
Construction material: Stainless steel

Operating principle

Decreasing velocity of wastewater flow causes sand to settle at the bottom of the sand trap trough. The horizontal screw conveyor (item 1) tranfers sand from the trough bottom to the settling funnel. The inclined screw conveyor (item 2) removes sand from the settling funnel. De-watered sand is transferred outside to a container.

Unit for Mechanical Treatment of Wastewater

This device is designed for complete mechanical treatment of municipal sewage and industrial wastewater. It consists of the following units:

Steel flow trough.
Fine screen at its inlet.
Screw conveyor at its bottom.
Sand separator in the settling funnel.
Control panel arranged near the device.

Unit for mechanical treatment of wastewater

Technical data

Channel width: 600mm-1200mm
Slot size: 7mm-12mm diameter
Power input: 4.5kW
Output: 40-160 l/s
Control: Automatic
Construction material: Stainless steel

Operating principle

Wastewater flows into the device through the fine screen where coarse solids are removed. The screenings are washed, de-watered and compacted on the screen and then transferred outside to a container. The wastewater flows on through the trough where sand settles on the bottom. The horizontal screw conveyor (item 3) transfers the sediment to a lateral settling funnel. The sediment is dredged out by the inclined conveyor (item 4) which de-waters it and transfers outside the settling funnel.