How Does Sand And Gravel Filter Water

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How does a sand filter work?

Sand filter

Written by Joshua Reijnen | Last update: 23-02-2020

A sand filter, or sand h2o filter, makes use of sand to filter h2o. The water to exist purified slowly sinks through the sand of the sand filter, leaving the dirt particles from the h2o behind in the fine pores of the sand. This filter technology is especially suitable for pre-filtration of disinfection equipment, preparation for micro- and ultra-filtration, recirculation systems, rinse water processes, irrigation systems, basin water filtration and ground water cleaning.

Please note: a sand filter does not filter dissolved salts from the water. A sand filter can only filter solid particles from the water, like algae and organic material. Salts that do not dissolve in water, like salts that appear in fertilizers, tin be filtered from the water by a sand filter, provided that the particles are large plenty.

How does a sand filter work?

How does sand filter water? A sand filter works equally follows. The unfiltered water is distributed in the top of the sand filter and volition slowly sink through the filter bed. This filter bed consists of sand, gravel or another filter medium. The modest pores ensure that the dirt particles are not able to laissez passer through and retain the clay particles.

Sand filter aftermath

When a certain quantity of water has been filtered or when the sand has reached a certain degree of pollution, the sand filter will automatically switch to backwashing. During the backwashing the pores enlarge upon which the dirt is done from sand again. Afterward, this clay is discharged, together with the backwash water. As a result, the sand filter will not go blocked, retaining its optimal purification qualities.

Diameter of the sand

The diameter of the sand is predominantly dependent on the size of the sand filter, the desired catamenia and the desired filtration. In most case, for the filtering procedure, sand with a diameter of 0.8 mm to 1.25 mm is used. This may nevertheless vary per installation. For example, a UV installation has a lower flow and sand of 0.4 mm to 0.8 mm will be used to filter more restrictively.

When the sand has a modest diameter, the resistance will be increased, resulting in less flow. For this modest diameter less chapters is required for backwashing, because the sand is lighter and volition thus hands launder with the dirt. Likewise, in instance of a smaller sand grain diameter, y'all should have into account that more than frequent backwashing should take place considering more dirt is being captured than when using a larger diameter.

Checking and maintenance of the sand filter

Check the filling of the sand filter periodically. If the filling clumps together or gets rubbed off, or if the sand filter requires frequent backwashing, then replace the filling. Also ensure that yous maintain the sand filter well.

Questions about sand filters every bit a filter applied science

Exercise you have a question about the working of a sand filter, how does sand filter water, or would you lot similar customized advice about this filter technology? So contact water specialist Joshua, or ask your question via below form. Nosotros will and then contact you as soon every bit possible, fifty-fifty within 24 hours on working days.

Well-nigh Joshua Reijnen
Joshua Reijnen is a product specialist in the area of water technology. In 2015 he started studying water direction, while working at Royal Brinkman as a trainee. Meanwhile, he has been supporting growers on a daily basis since 2017, by advising them about different kinds of h2o-related bug. "A satisfied customer and being able to really make a contribution; that is what I similar nearly nigh my task."