Textile fibers are widely used for fine filtration in the disposable cartridge filter market. The Amiad AMF2 filter uses fiber thread technology to create a self-cleaning filter system. The basic filtration element in a “Microfiber” filter is the “thread cassette”. Fine threads, which are 10 micron in diameter, are wound over a rigid grooved base plate. Water flows through the thread layers into the grooves and channel the water to specially designed outlets. The rigid base plate supports the thread layers and also plays a major role in the cleaning process of the media. The filter cassettes are mounted on hollow collector pipes.
The cleaning mechanics
High-pressure water jets spray through the thread layers hit the grooved base plate and reject back through the layers again. The contaminant is carried off the cassettes by the reject stream. Therefore, no dirt passes through the filter during back-flush. The filtration mechanics are a combination of surface and depth filtration. The design velocity through the media is 1-40 m3/h. The newly developed filters is efficient for Drinking Water filtration, including the removal of Cryptosporidium, as well as for Swimming Pools, Reverse Osmosis protection, Cooling Tower side stream filtration for Legionella reduction, etc.
The cleaning process
The filtered water flows from the four collector pipes to the filter’s outlets. As dirt builds up on and in the cassettes, the pressure differential across the cassettes increases. When the differential pressure reaches a pre-set adjustable level, it triggers the filtration system’s flush sequence. Flush sequences also can be triggered at pre-set timed intervals. The flush sequence is governed by an electronic control unit or by manual input.