Vertical tank filter

Pressure Leaf Filters Sometimes called tank filters, they consist of flat filtering elements (leaves) supported in a pressure shell. The leaves are circ ilar, arc-sided, or rectangular, and they have filtering surfaces on both faces. The shell is a cylindrical or conical tank. Its axis may be horizontal or vertical, and the filter type is described by its shell axis orientation. 

Pressure filters are available in either horizontal or vertical tank (vessel) arrangements, with manual or automatic backwashing facilities and with tanks constructed of steel or noncorrosive construction materials. Flow through the filters is normally from the top and then down through the bed. 

The typical back-pulse filter is a vertical tank pressure vessel with a conical bottom,... 

Pressure leaf filters are supplied in a wide range of size and materials of construction. One typical design is the Verti-jet unit with a vertical tank and vertical leaf filter, as shown in Figure 7.12, with rectangular leaves mounted individually but connected to a common outlet manifold. For sluice cleaning either a stationary or oscillating jet system... 

Various filter designs are available to the industry, including plate and frame filter presses, horizontal tank/ vertical leaf pressure filters with retractable bundles or shells, and vertical tank/vertical leaf pressure filters. The latter (Figure 29) has been accepted by the industry as perhaps the best overall choice in terms of price, performance, space requirements, and ease of automation. Filter sizes up to 85-m filter area/filter are available with this model. However, the horizontal tank/vertical leaf model with either retractable bundle or retractable shell also has its proponents. Commonly, a major factor in deciding on this type filter is the fact that these units are available in sizes up to 200-m filter area/filter. 

For more efficient leaf cleaning, horizontal tank-vertical leaf filters are made with various types of movable sluices. 

In comparison with nutsche filters, leaf filters provide more filtration area in the same volume of a pressure vessel. They are more suitable for handling larger quantities of slurry. Leaf filters can be subdivided into four classes in accord with the vertical or horizontal position of the tanks and leaves. In Figures 22.32 and 22.33, vertical leaves are shown in vertical and horizontal tanks. For vertical leaf filters, to prevent cake dropping, the cake thickness is normally restricted to 3.5 to 4.0... 

FIGURE 22.32 Vertical tank vertical leaf filter. 

FIGURE 58.4 Vertical tank, vertical leaf filter. (From Shirato, M. et al.. Filtration—Principles and Practice, eds. M.J. Matteson and C. Orr, Marcel Dekker, New York, pp. 299-423, 1987. With permission.)... 

Monel and lined carbon steel are standard materials of construction for filter vessels. Linings are similar to those used in primary filters. Figure 7.60 shows a typical vertical-tank vertical-leaf filter. The stream to be filtered enters the body of the tank. A bottom connection is shown, but there are other options. The leaves are arranged vertically, and flow is from the outside to the inside of the leaves. Filtrate collects in a pipe at the bottom this also serves as support for the filter elements. The tank also has drain, vent, and compressed air connections. The detail shows one type of assembly that can simply be lifted from the effluent pipe. O-rings supply the seals. 

A candle filter contains a number of cylindrical elements in a vertical tank, using materials of construction similar to those used in leaf filters. The elements can be built up, in modules similar to those used in mist eliminators (Section 9.1.5), or they can be solid cylinders made of carbon or a ceramic. The latter are porous, with walls about... 

Figure 3. Details of a typical vertical leaf pressure filter with vertical tank orientation.

Pressure-vessel leaf filters (a) vertical-tank, vertical-leaf filter, and (b) horizontal-leaf filter. 

Vertical-tank, vertical-leaf filters (Figure 12.6)... 

The tank-leaf pressure filter (Figure 50.4) features a number of leaves (filtering elements) suspended within a closed vessel. Common variations involve the arrangement of the tank and leaves into various vertical and horizontal combinations. Vertical tanks normally contain vertical leaves whereas horizontal tanks may have either vertical or horizontal leaves. The leaves are hollow shells fitted with support grids and covered with a metal gauze or woven fabric. They... 

Vertical tank with vertical leaf filters i.e., Niagara, Angola, and Pronto. 

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