From Dictionary of Water and Waste Management, Second Edition
vaccination of water velocity control grit chamber
vaccination of water
See stabilisation (1).
vacuum breaker
In a water supply system, a valve that closes under positive pressure and allows in air under negative pressure.
vacuum filter
A horizontal shaft, continuously rotating drum with filter cloth or metal coil stretched around it, subjected to vacuum inside the drum. The lower 25 to 40% of the drum is submerged in the fluid being filtered or dewatered. Rotation is slow, at 2 to 9 rev/min allowing a cake of sludge to form outside the cloth. There are several methods of discharging the cake, with, e.g. drum type filters having the cloth attached all the way round the drum, discharging by pressure blowback just ahead of the knife discharge. String discharge filters use strings about 1.3 cm apart passing around most of the drum but departing from it at the top over discharge rolls to carry the cake away from the drum. Belt type filters use a continuous woven cloth or metal belt which acts as the filter medium but it also is led away from the drum to discharge and washing rolls. This facility for continuously washing the cloth reduces blinding. Coil type filters use two layers of stainless steel coil springs which leave the drum in the same way as on the belt filter. The two layers are then separated and the cake discharges from the upper layer. The coils are washed and re-applied to the drum by grooved...
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WAC waste treatment WAC Waste Acceptance Criteria. waffle bottom anaerobic digester An anaerobic digestion tank built egg shaped which aims to reduce the need for cleaning. The...
Rotary drum filters consist of a large drum divided into circumferential sectors. Each sector forms a separate vacuum cell. Each sector has internal piping that connects to a port on the end of the...
Automatic pressure filters resemble filter presses, but with pressure plates stacked vertically instead of horizontally, changing the direction of filtration to the vertical direction. The slurry is...
Vacuum nutsches are designed to operate under either pressure or a vacuum. The majority of these filters operate under pressure in batch type processes, such as fine chemicals, pharmaceuticals and...
6.1 Batch Filter Cycle Configurations Depending on the type and mode of operation of a batch filter, a cycle may comprise up to two filtration phases followed by a number of compression, gas...
