Water with low to high polluting load, with organic and mineral origin for any type of use
- process water
- industrial water
- cooling water
- agricultural irrigation water
Unsuitable for well water with high amount of sand, instead, upstream sand separator recommended.
How It Works
Sand filtration is one of the most worldwide spread and oldest ways to filter. It imitates the concept of surface water, that percolates through layers of earth. In this way, suspended particles get retained in the intervals of the filtering element. As with a spring, water emerges cleaned from the filter and the dirt particles remain in the filter. Due to different forces, especially attraction generated by friction, even smaller particles get retained. The speed of the water flow and the depth of the filter bed are crucial for the quality of the filtering process.
By the reversal of the water flow (backflushing), the filtering element is cleaned. The filtering bed is restored for many cycles. This type of filtration is suitable for almost all kinds of water and impurity, including very small particles of organic as well as of mineral origin. Due to the large filter surface area, water with high dirt load can be successfully processed. The eventual addition of a chemical pretreatment (flocculation) makes it possible to achieve excellent results. The principle of sand filtration is not suitable for well water with high amount of fine sand. For this purpose, so-called pre-filtration/ sand separators should be preceding.
It is possible to back-flush manually or all-automatically controlled by pressure difference. The backflushing results from the reversal of the water flow through the filtering medium. By this, the filter medium creates a sensation and the detained dirt is flushed out with the backwash water. Periodic and especially timely backflushing is required for a failure-free operation. Otherwise, the filter medium gets clogged. Rifts are formed through those raw water can enter unfiltered.
Sand filter available in diverse versions
- applications with PVC underdrains
- applications with filtering nozzles and filtering bottom
- standard container made out of steel with epoxy coating
- standard bed height (diameter = 2/1 to 1/1-) →especially for agricultural applications
- deep sand filter (diameter 1/1 to 2/1-) →especially for industrial applications and drinking and process water
- volcanic filter gravel (standard)/ with large-sized pore void volume for high dirt holding
- quartz sand/ gravel with different grain sizes, also combined high level filter systems for especially good results
- anthracite coal
- special filling (marble gravel, ion exchanger resin, etc)