Filtration mechanism bridging

The two special filtration mechanisms, sieving and bridging, in the blood filtration process are explained below, and the other five filtration mechanisms can be seen in Section 6.3. 

The camera, including the lens, is cooled in the harsh environment by compressed air from a mechanical air conditioner that circulates under positive pressure to cool the camera housing. Compressed air from a separate source goes through the protective lens tube and out its end. An air filtration system removes aerosols, vapor, oil, and particles as small as 0.03 microns. Automatic retractors pull the tube and camera back about 2 feet if the kiln shuts down. Additional cameras can be mounted in the clinker-cooler area to monitor "bridging," where material could accumulate and block removal of the cooled limestone. 

Cake filtration this is undoubtedly the most widely encountered mechanism in industrial filtration and involves the accnmulation of particles that bridge together in a porous structure on the surface of the fabric. It follows from this that, once formed, the cake effectively becomes the filter medium, with the fabric thereafter acting simply as a support. In cases where it is difficult for the particles to form a naturally porous cake, the use of a special precoat or body feed may be employed to assist in this task. 

Selective deposition is indicated by poor separation of the solids fi om the filter cloth The presence of a heavy reridnal cake on the sur ce, after cake discharge, may be fire resuh of preferential deposition of fines. One control mechanism here is to increase the effective solids conemtration before filtration, e.g. by settling or hydrocyclones. As discussed in later sections dealing with particulate bridging increases in concentration generally lead to the creation of stable bridges. 

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