Safe drinking water is a necessity for all. However, the abundant available water globally cannot be deemed to be safe for drinking. The presence of unwanted media in water makes it unsafe and if consumed can cause health risks.

This is why water filtration is an essential process that is adopted in water treatment industries to ensure pure and safe drinking water is supplied. Now, there are many filtration methods and one of them is the sand filtration system.

As the name suggests, this filtration system uses sands and other particles such as pebbles, gravels, etc. of different sizes. The porous nature of sand helps in trapping the unwanted media in water and filtering it in the process.

Keep reading till the end to learn all things essential about the sand filtration system.

What are Sand Filters?

Sand filters are one of the water treatment processes that uses sand in the filter vessel. The use of different particle sizes of sand is contained in the vessel and a double-bottom collector is fitted.

The porous nature of sand works to trap the unwanted presence in water such as bacteria, protozoa, etc. and reduce the concentration of a series of particulate and dissolved matter.

Sand filters come in a variety of sizes and you can choose the ideal size depending on the flow rate of water. The sand used in filters are generally in a plastic, steel or concrete filter.

Rapid vs Slow Sand Filtration System

Rapid sand filtration system is used primarily for disinfecting and eliminating the color from the water. The base material for this type of filtration system is mainly gravel and it ranges from 0.6 to 0.9 mm in depth. The gravel base helps in uniform distribution of water over the sandy surface.

It is well-known for treatment of turbid water. However, it is effective for removing only 80% to 90% of bacteria from water. The construction of this system is a bit complicated and also has a bunch of pre-treatment requirements such as coagulation, sedimentation and flocculation.

Whereas, Slow sand filtration system also has a gravel base but its depth ranges from 0.3 to 0.75 mm. It is simple to construct and is more effective than rapid sand filters in removing bacteria. Almost 98% to 99% bacteria can be removed with the use of this filtration system.

The disinfection is improved; however, removal of color or turbidity can be less effective. Even though the initial cost can be high, the overall operations and maintenance cost is less.

Things that can be removed with Sand Filters

Sand filtration system is a multimedia removal system that can filter a range of particles from water. The following are some particles that can be filtered with the use of sand filters.

·        Insects

·        Bacteria, viruses, protozoa

·        Sludge

·        Seeds

·        Solid particles

·        Manganese particles

·        Precipitated iron

Sand filters when combined with other water treatment methods can offer you high performance results. They are pretty easy to operate and have overall low maintenance needs. Make sure to check out the sand filtration system before settling on a water treatment process.