Noardling Hubert - Micro Screen
A Hubert micro screen is applied in places where high demands are made on the purity of surface, process and re-circulated water. Hubert micro screen or microstrainer can be found in freshwater intakes, acting as fine pre-flit ration system of potable water for production plants, or production plants that consume a lot of processwater. This filter can also be applied for process water recirculation. The recovery of useful raw materials from process water, stricter discharge requirements, and recycling of process water makes the use of these engineered filters increasingly interesting. Other applications are treatment of effluent in a wastewater treatment plant and pre-flltratton in membrane filtration systems.
Design and construction
A Hubert micro screen is a rotating cylindrical construction, provided with a filter medium at the perimeter consisting of one or more layers of woven wire mesh. This filter is placed in a concrete container or steel tank and is usually applied under free fall conditions. Flow rates can be up to 5,000 cubic meters per hour per screen, depending on customer requirements and the application.
The woven wire mesh has a nominal filter rating (mesh opening or aperture) of 11 to 500 microns. The filtration fabric is supported by coarse mesh and sometimes reinforced with perforated plates. The efficiency and capacity of a micro screen strainer depend on several factors, including the characteristics of the fine filtration fabric, the rotation speed of the micro screen, the composition and quality of the water to be purified, and the amount of backwashing water.
It is important to mention that there is no standard method known to determine the nominal filter rating of a woven wire mesh. Depending on the filter fineness, different types of weaving patterns are possible. Therefore, the standard data often stated should be used with care. As a result, this type of filter is almost always first tested in a pilot setup in the field, often with different media.
Also, the composition of the water (including changes due to factors such as seasonal influences and location) has a major influence on the filter results. In consultation with the customer, it is determined which filter mesh will achieve the best result.
Standard Dimensions and Materials
- Drum length: up to 6 m
- Drum diameter: from 0,7 up to 3,5 m
- Mesh opening from: 11 to 500 micron
- Light, stable, and robust construction
- Reliable
- Maintenance free
- Long lifetime (30 years or more)
- Resistant to abrasive water