Filter bags for liquids are effective in removing particulate contaminants in the processing of a wide variety of materials. Bag filtration is a pressure-driven operation, wherein the product to be filtered is forced through the filter unit. Such a unit would normally consist of the filter housing, a retaining basket and the filter bag. Generally […]
The flat elements employing a thick filter medium and working by depth filtration, are distinguished here, as filter pads, from those using thin sheet media and working by surface filtration, which are called filter panels. The basic need of all kinds of filter is to maximize the available filtration area, and a single thin sheet […]
The pad filter (often called a cassette) is a special case of the range of panel filters, all of which are made in standard sizes, to fit air-conditioning installations. The pad, as its name implies, is a thick flat sheet of fibrous filter medium, made either by wet-laying (as in paper) or by dry-laying (as […]
The requirements for dust filtration vary considerably with the particle size of the dust material, and with its concentration in the suspending air or gas (and also with the velocity of the suspending gas). Where the concentration of the solids is reasonably high, the most likely separator would be a cyclone, or even a simple […]
From the complexities of the centrifugal filter, the Handbook moves on to one of the simplest forms of filter, used mainly for dust removal from air, in ventilating situations. These are the pad or panel filters, consisting of thick sheets of filter medium, or thinner materials folded to occupy the same space as a pad, […]
The moving bed centrifuge with a cylindrical basket is known as the pusher centrifuge, and is one of the most common types of centrifuge for separating fast-draining crystalline or fibrous solids from suspension, at high throughput rates of solids. In its basic action, a layer of filter cake forms on the inside of the basket, […]
There are two main designs of moving bed centrifuge: those with a cone-shaped basket and those with a cylindrical basket. In the latter, solid movement needs mechanical assistance, but in the conical basket, the solids are potentially free to slide from the narrow end of the cone, which is where the feed zone is, to […]
The fixed bed centrifugal filter is thus a batch-operated device for recovering solids from liquid suspension. All types have cylindrical baskets, open to the atmosphere (or to the enclosing casing) at one end. Filtrate passes through the filter medium and the developing cake, into the casing and so to a filtrate receiver. The formed cake […]
Centrifugal separations are of two broad kinds, those using filtration and those operating by sedimentation. The latter are covered in Section 7, while centrifugal filters are the subject of this part of Section 3. Also broadly classifiable into two types, centrifugal filters, which are essentially devices for recovering solids from liquid suspensions, are defined by […]
The vacuum belt filter employs a continuously moving horizontal belt of filter medium, commonly of woven wire mesh, moving between two rollers. In the forward direction, a suspension, of medium to high solids concentration, is fed onto the upper surface of the belt close to one roller. The cake formed in the feed zone is […]
