High-gradient Magnetic Filters
High-gradient Magnetic Filters (HGMF) are advanced filter systems developed for controlling and removing coarse particles from industrial sewage and other liquid streams. Featuring robustness and high efficiency, they are applied in water and wastewater treatment, coal and polymer processing, and specialty chemicals. HGMF are applicable to treating streams with broad solids size distributions, rather than narrow ones.
They are widely accepted in various industries as mature and effective technology. Using these filters in many applications has proven to be both economical and reliable. HGMF have been used to remove various suspended solids on the order of 50 μm down to less than 1 μm. The filter’s separation efficiency range is between 50 and 100 µm particles.
The technology of an HGMF is based on the magnetic attraction of certain elements in the solid that are magnetically sensitive. When water and other liquid streams with suspended solids pass through a filter, the magnetic field generated by the filter entraps or traps the magnetically-sensitized particles. The filter then uses a mechanical process to separate the particles from the liquid feed, producing filter cake or slurry.
HGMF typically consists of permanent magnets and an assembly of specially designed components. The filters usually come in two basic configurations, either vertical or horizontal. Each design depends on the kind of solids that need to be removed from the liquid.
In vertical layouts, the solids are trapped between two plates as the liquid flows upward. This system applies a strong magnetic field to the particles, causing them to stick together while the liquid continues to flow. During the filtration process, the liquid and particles can separate more efficiently since the fine particles are attracted by the magnets and stick to each other.
In horizontal layouts, the filter has a stationary filter bed at the bottom. This filter bed has a magnetic filter material that is attached to the bottom of the filter unit blades. As the water and solids move through the filter, the blades create turbulence and attract magnets to the particles. This process helps to entrap them and separate them from the liquid stream.
The main advantages of using HGMF for treating liquid streams are their high recovery rates, high efficiency, and low maintenance costs. Furthermore, these filters are usually easy to install and use, making them an ideal solution for many industrial applications. They are also particularly useful for treating water or wastewater containing fine particles that are difficult or impossible to remove using conventional filter systems.
In conclusion, high-gradient magnetic filters are the preferred filter choice for aggressively separating and removing fine particles from liquid streams. Thanks to their low operating costs, ease of installation, and high efficiency, they are increasingly being used in various industries.
