Sand

Sand is used in water purification as a filter medium to remove suspended particles, organic matter, and microorganisms. The water flows through a bed of sand, and contaminants are trapped in the spaces between the sand grains or adhere to the sand's surface, resulting in cleaner water.

Here's a more detailed explanation:

Removal of Suspended Particles:

Sand filtration effectively removes solid particles like dirt, sediment, and sludge from the water, improving clarity and reducing turbidity.

Microorganism Reduction:

While not always capable of removing all microorganisms, sand filters can significantly reduce the population of bacteria and protozoa through physical and biological processes within the filter.

Types of Sand Filters:

• Slow Sand Filtration: Uses a bed of fine-grained sand to filter water slowly, relying on natural processes like filtration and biological activity to remove impurities, according to Wikipedia and a blog on zuiveringstechnieken.nl.
• Rapid Sand Filtration: Filters water faster and often uses a mix of sand and gravel, which may involve flocculation and coagulation to remove particles before filtration, according to an article on expresswatersolutions.com.
• Applications: Sand filters are used in various settings, including municipal water treatment, swimming pools, irrigation systems, and industrial processes.