|Enhanced polypropylene plate-and-frame filter press"|
A plate and frame filter press is the most fundamental design, and many now refer it as a "membrane filter plate". Filter press consists of an array of filter chambers containing filter plate and filter frame arranged alternatively. There are grooves on the surface of filter plate, and the protruding parts are used to support the filter cloth. The filter frame and corners of filter plates are provided with through-holes, forming a complete channel after assembly, which is available for passing through of suspension liquid, washing water and filtrate extraction. The beam is set with handle brackets at both sides of filter plates and frame pressed by the pressing device. The filter cloth between plates and frames has sealing function. The suspension liquid is pumped into the filter chamber by the feed pump, forming filter residue on the filter cloth until the filter chamber is filled up with filter residues. Then, the filtrate will penetrate the filter cloth and flow to the corner channel of the filter frame and plates along the filter plate groove to be discharged in a concentrated way. After filtration, the filter residue can be washed with washing water. After washing, compressed air may be pumped in to remove the residue washing liquid. Then the filter press can be opened to remove the filter residue, wash the filter cloth, compress the plate and frame and start the next working cycle.
Filter presses are used in a huge variety of different applications, from dewatering of mineral mining slurries to blood plasma purification. At the same time, filter press technology is widely established for ultrafine coal dewatering as well as filtrate recovery in coal preparation plants. According to G.Prat, the "filter press is proven to be the most effective and reliable technique to meet today's requirement".One of the examples is Pilot scale plate filter press, which is specialized in dewatering coal slurries. In 2013 the Society for Mining, Metallurgy and Exploration published an article highlighting this specific application.It was mentioned that the use of the filter press is very beneficial to plant operations, since it offers dewatering ultraclean coal as product, as well as improving quality of water removed to be available for equipment cleaning.
Many specialized applications are associated with different types of filter press that are currently used in various industries. Plate filter press is extensively used in sugaring operations such as the production of maple syrup in Canada, since it offers very high efficiency and reliability. According to M.Isselhardt, "appearance can affect the value of maple syrup and customer's perception of quality".This makes the raw syrup filtration process extremely crucial in achieving desired product with high quality and appealing form, which again suggested how highly appreciated filter press methods are in industry.
China Plate-and-frame Filter Press