Filter media edge filters

There are, however, certain special applications where the filter medium around the edge of the section may be dehberately blinded by painting in order to improve cake discharge. This technique is most frequently used on disk filters, with the result that the actual area may be only 75 to 85 percent of the nominal area. This is a significant deviation from the nominal area and must be considered separately. 

In each filter plate, the filter medium is attached to a moving belt (Fig. 18-190). An elastomer seal is used at the edge of the filter chamber. The slurry is fed into the filter chamber, and the operation starts as a pressure filtration. After filtration, the diaphragm is inflated to squeeze on the... 

Knife discharge following a previous reverse air blast. Here a reasonably fiiick cakei is required, and sometimes it is necessary to protect the filter medium, hich covers the drum, by using a mbber- or plastic-edged knife. The blow-back technique can create a rewetting of the partially dewatered cake with filtrate v hich remains undrained in the conduits behind the fiber cloth. 

The edge filter is of a solid fabrication structure wherein the medium consists of the edges of a stack of specially formed washers or thin discs mounted on a central perforated core (shaft), and held under compression so as to form a continuous cylindrical outer surface. Each washer has grooves or scallops cut into it, such that very fine and carefully controlled gaps occur between the adjacent washers. The gaps are usually sized from 5 pm upwards. Filtration takes place by flow of liquid inward through the narrow gaps between adjacent discs. The filter is essentially a strainer in that particles are stopped on the outside surface. The discs are usually metal but they can be nylon, polypropylene or paper. 

Mount on a slide in 60% glycerol in PBS and cover with a coverslip. Flatten the specimen by wicking out excess mounting medium with filter paper strips applied to the edges of the coverslip. 

It should be noted, however, that the edge filters described in Section 2E are also mainly made of metal and made with precise apertures. It should also be noted that every type of filter medium described in this part as made from metal can also be made of plastic materials, with almost as much strength and almost as much precision in aperture size. Corrosion resistance may actually be higher with plastic wire screens or sheets than for some metals. 

The filter pocket is just as its name implies two rectangular sheets of filter medium, placed side-by-side, joined together at three edges, the fourth being open. Pockets are used almost exclusively for air cleaning, in which function they act, Uterally... 

The surface of the flush plate was machined or moulded to provide flow channels for filtrate liquid to run across this surface to the filtrate discharge point(s). A sheet of appropriate filter medium would be placed across the face of the plate, to be supported by the edges of the plate and by the shoulders of the flow channels in it. The frame would then be clamped to the plate, with its sheet of medium, by an identical plate on the other side of the frame. The plates would be double sided, so that each plate could be part of two successive chambers. 

Imaging system it ordinarily contains little reflector, cutter point, filter, special lens and imaging medium. The cutter point includes black-white and color edge and is the key component of schlieren apparatus. It is parallel to the source slit and is located in the focal plane of reflector. When there is no disturbance in the flow field, if the knife cut off part of the image of the source, light intensity on photographic plane will weaken uniformly. Black and white edge has steel sheet with... 

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