Design Features and Experience of Porous Drainage Systems Operation in High-Rate Filters

Summary

Design features and multiyear experience in operation of porous drainage systems of two types in high-rate filters are expounded. Drainages ensure a high level of uniformity of washing across the filters’ area.

Key words:

potable water , fitlters , drainage system , granular media , granules , porous layer

Designing drainage systems of flooded areas on the basis of computer simulation

Summary

To make hydrogeological calculations of drainage systems for protecting territories from floods the methods of analogy, analytical and computer simulation are used. The method of computer simulation as applied to designing drainage systems on the territory of the Imeretinskaia Lowland of the Krasnodar Area is closely considered. The analysis of the model map of ground water depth after territory upfilling and building development provided for identifying the areas to construct the systems of engineering protection from flooding. The basic design solution of reducing ground water level on the flooded territories is constructing horizontal subsoil pipe drainage with filtering bedding or radial horizontal drainage. Depending on the results of the mathematical simulation of the hydrogeological conditions on the protected area and hydrogeological calculations pipe drainages of perimeter, linear or systematic (areal) type are constructed. Ground water by gravity is diverted into open-channel flows provided the proper ecological justification is available. As may be required automated drainage pumping over stations are established. The developed concept allows reducing and maintaining ground water level at the permissible depth.

Key words

filtration , drainage system , numerical simulation , territory underflooding , ground water , hydroisohypses

Efficient methods of rapid filter wash

Summary

This paper dwells upon rapid filter wash methods, focusing on air washing that significantly reduces water consumption, pumping equipment size, and facility volume. The operating principles of rapid filters including their design and drainage systems are discussed. The filtration process and filter media specificity are described. Also discussed are the disadvantages of the traditional water washing, such as hydraulic separation and high water consumption resulting in the operating costs increase. The proposed methods for improving the wash efficiency, including the use of air-water washing technology and wash intensity alternation, highlight the importance of innovative approaches in water treatment.

Key words

water-air flushing , drainage system , water treatment , rapid filter , filtering material