Industrial filtration dust collection

Key words industrial filtration, dust collection, solid-liquid filtration, cake filtration, thermal and chemical conditions. 

It has been argued that the theories behind these mechanisms may be valid for certain air filtration applications, where total-particle capture is vital however, for the purposes of industrial dust collection, they are of limited value. A sieving mechanism is probably more appropriate wherein the size of the apertures in the medium assumes a more dominant role, at least until the fibres have accumulated a layer of dust which then takes over the sieving action. 

Conversely, by constructing the filter medium with a blend of fibres of widely contrasting triboelectric properties, it is claimed by a fibre manufacturer that superior collection efficiency can be obtained. It is further claimed that, by virtue of this enhanced efficiency, a more open structure can be used with consequent advantages in respect of the reduced power consumption required to pull the dust-laden air through the collector. However, although this effect has been used to some advantage in clean air room filtration applications, considerably more research is necessary if the triboelectric effects in industrial dust collection are to be fully understood and exploited. 

Abstract Industrial filtration operations involving textile filter media are found in the production of countless items that we encounter in our everyday lives, and yet more operations are engaged in protecting the environment. The chapter attempts to provide a brief overview of the filtration mechanisms that are involved both in industrial dust collection and solid-liquid separation processes, and the equipment types that are engaged in each. The chapter also describes the types of textile filter media that are employed in the various operations, their component strengths and weaknesses, and some of the finishing treatments that are applied to enhance their efficiency. 

The field of filtration in its widest sense covers the capture of particles ranging in size from several millimetres down to the molecular scale. Table 71 provides an indication of the various particle size ranges, and where textile filter media fit into this picture. The industrial filtration processes on which the chapter will concentrate are separated into two broad sections, namely, the separation of solids from gases, more commonly referred to as dust collection, and the separation of solids from liquids, usually referred to as liquid filtration. 

Needlefelts are not as widely used in liquid filtration as they are in dust collection. Unless required for depth straining, as in the viscose industry, or unless the particles can be restricted to the surface as in some filter belt mining applications, the risk of premature blinding through pore blockage is always a threat. 

In factories, a dirty atmosphere can produce an unpleasant working environment, reduce operator efficiency, shorten the life of machines, increase maintenance costs and contaminate products. The problem of air treatment is aggravated by the abnormally high concentration of heavy and/or abrasive contaminants in the industrial atmosphere. Full control may be beyond the scope of conventional filtration systems (or be uneconomic to apply). In this case, special dust collecting treatment may need to be applied to specific areas (a topic further discussed in Section 6D). 

Airflow Systems, Inc Resource for the collection and filtration of dust, smoke, mist, fumes and other airborne contaminants generated during industrial and commercial manufacturing and processing applications. http., llwww.air, flowsvstems. com... 

One of the oldest, simplest, and most efficient methods for removing solid particulate contaminants from gas streams is by filtration through fabric media. The fabric filter is capable of providing high collection efficiencies for particles as small as 0.5 pm and will remove a substantial quantity of particles as small as 0.01 pm. In its simplest form, the industrial fabric filter consists of a woven or felted fabric through which dust-laden gases are forced. A combination of factors results in the collection of particles on the fabric filters. When woven fabrics arc used, a dust cake eventually forms. This, in turn, acts predominantly as a sieving mechanism. When felted fabrics are used, the dust cake is minimal or nonc.xistent. 

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