Filter dimensions, pressure filters

Horizontal pressure leaf filters. In these filters the leaves may be rectangular leaves which run parallel to the axis and are of varying sizes since they form chords of the shelf or they may be circular or square elements parallel to the head of the shell, and all of the same dimension. The leaves may be supported in the shell from an independent rack, individually from the shell, or from a filtrate manifold. Horizontal filters are particularly suited to dry-cake discharge. 

Work during the 1960s on the CB Pressurized Pod resulted in the standardization of the M51 Shelter System in 1971. The unit was an easily transportable, pressurized enclosure. It could be air-dropped or towed to provide protection from chemical and biological agents in the field for combat, combat support, and combat service support troops. The M51 was a double-walled, air-inflated, self-supporting shelter and airlock structure. When erected, the shelter was semicircular in cross-section with a maximum inside height of 7.5 ft, with inside dimensions of 15 x 14 ft. An airlock entrance (with a set of double doors at each end) on the front was 11 (1) x 4.2 (w) x 6.7 (h) ft in dimension. The filter and support equipment were mounted on a two-wheeled trailer.186... 

To save energy, the filter is dimensioned in normal ventilation plants, often with a lower final pressure loss than indicated by the classification, and the filter does not achieve the intended filter classification. For reasons of hygiene, the filter is replaced after a certain period of time, rather than a specific final pressure loss. 

The final pressure drop is dimensioned and selected with regard to permitted variations in flow, the filter s life-cycle costs, and life-cycle analysis. 

Filters must be replaced when the pressure loss reaches the dimensioned final pressure loss or when the following hygiene interval is reached, if this is earlier ... 

Ultrafiltration is an improvement on the dialysis principle. Filters having pore sizes over the range of biomolecular dimensions are used to filter solutions to select for molecules in a particular size range. Because the pore sizes in these filters are microscopic, high pressures are often required to force the solution through the filter. This technique is useful for concentrating dilute solutions of macromolecules. The concentrated protein can then be diluted into the solution of choice. 

A continuous rotary filter is required for an industrial process for the filtration of a suspension to produce 0.002 m3/s of filtrate. A sample was tested on a small laboratory filter of area 0.023 m2 to which it was fed by means of a slurry pump to give filtrate at a constant rate of 0.0125 m3/s. The pressure difference across the test filter increased from 14 kN/m2 after 300 s filtration to 28 kN/m2 after 900 s, at which time the cake thickness had reached 38 mm. What are suitable dimensions and operating conditions for the rotary filter, assuming that the resistance of the cloth used is one-half that on the test filter,... 

Scale-up of IFF processes is usually done by arranging a large number of short devices in parallel. The individual filters should be kept relatively small in axial dimension, helping to avoid the excessive build-up of feed pressure resulting from the pumping of viscous slurries [96]. By arranging TFF membranes in parallel or in series, units can be scaled-up to process thousands of liters of cell culture fluid in a few hours [1]. 

The Model 835 multiwavelength filter photometer (Fig.3.44) provides energy at 254 nm with a low-pressure mercury lamp and at 280,313,334 and 365 nm with a medium-pressure mercury source. Selected wavelengths between 380 and 650 nm are also available with a quartz-iodine light source. Absorbance ranges of 0.01-2.56 AUFS are provided. Short-term noise levels are 5 X 10-s AU with the low-pressure mercury source and 1 X 10 4 AU with the other lamps. The design and dimensions of the cell are the same as for Model 840. A 24-jtzl cell is standard with the medium-pressure mercury lamp and the quartz—iodine lamp. 

A schematic of a monolith catalyst is shown in Fig. 19-18a. In cases where pressure drop is limiting, such as for CO oxidation in cogeneration power plant exhausts, monolith catalyst panels may be stacked to form a thin (3- to 4-in-thick) wall. The other dimensions of the wall can be on the order of 35 x 40 ft. CO conversion is over 90 percent with a pressure drop across the catalyst of 1.5 in of water. Alternatively, the monolith may be used as a catalyst and filter, as is the case for a diesel particulate filter. In this case, monolith channels are blocked and the exhaust gases from a diesel truck are forced through the walls (Fig. 19-18b). The filter is a critical component in a continuous regenerable trap. NO in the exhaust... 

A schematic presentation of one of the most convenient modifications of these cells is given in Fig. 8.2. It represents a glass cuvette 1 (internal dimensions 5x3 cm and 7 x 1.7 cm), made of transparent optical glass, sintered glass filters 2 for creating a definite capillary pressure and electrodes 3 for measuring foam electrical conductivity. 

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