What is a sand filter?
Sand filters are called tanks made of steel, concrete, fiberglass, etc., which are manufactured under atmospheric pressure. These tanks are often cylindrical and circular and sometimes square. As its name implies, pure sand is used in their beds.
Sand filters are typically used to remove all types of biologically suspended particles in water up to 50 microns in diameter. These impurities can include all kinds of organic matter, plankton, bacteria and particles resulting from corrosion, mud, paint, and so on. This cleanup is done in the early stages of industrial water treatment systems. Carbon filters are also often used in the water treatment path after these filters.
The sand filter system with physical water filtration eliminates suspended particles and turbidity in the water. In this machine, water containing turbidity is passed through a bed containing sand and silica grains. As water passes through the sandy bed, the water suspended between the sand particles and the water is almost free of suspended matter and turbidity. Sand filters are one of the best ways to reduce the concentration of suspended solids in water. These filters have a substrate consisting of one or more types of layers, each containing particles of rock, granite, or anthracite grains. The grain and size of these particles also differ.
Using Under pressure sand filter
The sand filter is used as an effective step in the water treatment process. There are four main types of this device: pressure sand filters, gravitational sand filters, upstream filters and slow sand filters. All four methods are widely used in the water industry worldwide.
The first two need fluculent chemicals (substances that accumulate all kinds of particles and substances in water) to work effectively. While slow sand filters can produce very high quality water by removing the pathogen from 90% to 99% (depending on the type), with a good taste and odor, without the need for chemicals. Sand filters, regardless of being used in water treatment plants, are also used for water treatment and purification in residential and other commercial areas.
The most common type of sand filter is the under pressure sand filter. This type of filter is often used in pools. And it can offer very acceptable speed while doing a good cleaning.