초록 ▼

By this method, the fluid to be filtered is led through a filter bed formed of particulate filter particles, such as sand, which filter bed is retained in an upstanding annular space. The fluid is introduced to the interior part 15 of the annular space and is led transversely to the movement the fil

By this method, the fluid to be filtered is led through a filter bed formed of particulate filter particles, such as sand, which filter bed is retained in an upstanding annular space. The fluid is introduced to the interior part 15 of the annular space and is led transversely to the movement the filter bed, through it and away. The filter bed is provided on the inner wall of annular space with a microfilter, such as sieve grid 16, with a mesh size of 10 to 200 microns, whereby the heavy and flocculated dirt particles settling upon the microfilter are led down and away and are drawn off together with the particulate filter particles 32. To avoid stoppages of the microfilter, it is flowingly hydraulically cleaned from the inner space. Additionally, by introduction of water in the take-off space 11 there is produced a vortex bed, whereby at this space the withdrawal of the particulate filter medium is effected with a mammoth pump 17 known per se. The compressed air for the operation of the mammoth pump 17 is supplied not steadily but pulsatingly. Thus, there are provided in the vortex bed in combination with the water supply thereto some hydraulic pulses which serve to hinder the development of bridges in and above it.

대표청구항 ▼

In an apparatus for the continuous filtration of liquids, said apparatus having a central receiving area and an upstanding outer area of substantial height; means for introducing a liquid to be filtered into said central receiving area, an upstanding liquid-permeable wall having a microfilter arrang

In an apparatus for the continuous filtration of liquids, said apparatus having a central receiving area and an upstanding outer area of substantial height; means for introducing a liquid to be filtered into said central receiving area, an upstanding liquid-permeable wall having a microfilter arranged between said central area and said outer area to allow the liquid to pass through said microfilter from said central receiving area to said outer area, particulate filter-media particles arranged in said outer area adapted to receive liquid passing through said microfilter, said particles forming an upstanding filter bed, means for collecting said filter particles at the bottom of said filter bed, means for introducing during said collection a liquid into said filter particles at the bottom of said filter bed to produce a vortex action on the particles, means for transporting the particles inwardly through said central receiving area to the upper portion of said outer area for recirculation downwardly through said outer area, and means for applying a liquid to said microfilter during the filtration to cause a removal of the relatively heavy and flocculated impurity particles deposited on said microfilter in a manner to cause the removing liquid to carry said impurity particles to the bottom of said filter bed.