Filter cloths provided with the filter press have been selected specifically for use on each particular application. Proper care and maintenance of the filter cloths are important to the performance of the filter press. During filtration, the filter cloth is the initial barrier that separates solids from the liquid. Therefore, the filter cloth must remain porous to provide high filtration rates.
During normal operation, the filter cloth may gradually become plugged with microscopic particles. These particles penetrate the cloth and become lodged in the depth of the weave, which leads to decreased filterability. These particles must be removed periodically to maintain high filtration rates and drier cakes.
Filter cloth washing is required when one of the following factors indicate plugging has occurred.
There are several methods used to wash the cloths while they are installed on the press. The most commonly used method with metal finishing sludge is acid washing, which requires the following:
Met-chem offers a customizable Acid Wash System which includes a skid-mounted platform with a holding tank, mixer, controls, and a diaphragm pump. The Acid Wash Station will clean filter cloths and maintain high levels of filtration. These system can be installed with the purchase of a new or used filter press. They can also be added to your existing filter press (some plumbing changes may be required). After installation, please follow the procedures for Acid Washing Filter Press Cloths.
Caution: Acid washing is not recommended on non-gasketed filters unless extra precautions are taken to contain the leakage between plates.
Customers can also acid “dip” wash the plates by immersing them in a tank of 3-5% acid and water mixture. The immersion method though is less efficient than through washing in the press and will require at least an overnight soaking to clean out the depth of the weave. Polypropylene plates are lighter than water and will float, so they will need to be manually kept submerged.
Another method used for cloth washing is a portable high-pressure (800-1200 PSI at 2-10 GPM) cold water spray unit. These units come with a hand held power wand with spray nozzle, which is slowly moved over the cloths. This method cleans by not only flushing off the cloth surfaces but by also penetrating the cloth to flush particles out of the depth of the weave. Contact Met-Chem for more information on availability of units.
Met-Chem, Inc.
837 East 79th St.
Cleveland, OH 44103
Phone: (216) 881-7900
Email: info@metchem.com
A Senney Enterprise Company
Copyright © Met-Chem, Inc
