Backwash filtration device
Abstract
Abstract 1. A backwashable filter installation for the purification of water, comprising at least one filter bed having a base bearing a layer of granular filter material, in or on which base drainage pipes are laid for collecting the filtrate, said pipes leading into a filtrate collecting duct beneath the level of the filter bed, the installation being provided with a backwashing system for combined air and water washing of the filter bed, the backwashing media further being supplied and distributed through the drainage pipes, which are provided with connecting pipes extending into the collecting duct and having at least one air inlet aperture, and the feed pipes for the backwashing medium are connected to the collecting duct, characterised in that strainers (15) with the strainer heads (3) extending downwards are fitted into the drainage pipes (2), said heads being formed with passage apertures (33 and 31) of different total cross-section for washing air and washing water, at least the large cross-section passage apertures (31) intended for the water being closable.
Inventors
- 👤 Paul Brulhart
- 👤 Josef Tylmann
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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