Sand and Carbon Filter Media for Filteration

Water filtration has many filter options, from Anthracite to Limestone. Out of all filter media, sand, and carbon filters are widely used for water filtration and desalination. They both work to remove harmful particles from water, even though they function differently. The sand filter's fine pores allow water to pass through and trap dirt particles slowly. Sand filters are universally used for various types of water treatment, including groundwater cleaning, rinsing water processes, re-circulating systems, and irrigation systems. In this blog, we will discuss sand and carbon filter media for desalination, along with their differences and benefits.

What is a Sand Filter?

These filters are essential parts of any water filtration or desalination procedure. They are filled with sand of different particle sizes so that nothing gets past it. Although the size of the sand filter depends on the liquid's flow rate, it is usually placed at the beginning of the process. The water first passes through a sand filter before going into an activated carbon filter.

What is a Carbon Filter?

Activated Carbon filters are important for water purification as they remove chlorine, odors, volatile organic compounds, and unpleasant tastes from water. The use of activated carbon as a filter media results in its high porousness and extensive surface area. Heavy metals and impurities get absorbed or removed when passed through the filter. Finally, the water that leaves this filter is much cleaner than before.

How Does a Sand Filter Work?

The sand filter media works when water moves from the top of the tank through the sand to the bottom of the tank. High pressure is applied to make the movement smooth. As the water passes down, the sand grains collect particles such as dirt, debris, and body waste materials in them. Bit by bit, even the smallest particles are removed from the water as it passes through the sand, and the sand becomes denser and requires cleaning. 

To clean the sand filter media, it needs to be backwashed. It can be backwashed by both manual and automatic methods. In backwashing, the sand filter reverses the flow of water through it, so starting from the laterals at the bottom and working the way to the top while taking out the collected debris and particles with it. After the water goes through the whole sand filter, it is then sent to the waste instead of the pool. It only takes a couple of minutes to finish backwashing, so it doesn’t take much time and doesn’t need any labor. Once backwashing is completed, the system is rinsed, and the clean sand resumes filtering the water.

How is a Carbon Filter Different from a sand Filter?

Although both sand filters and carbon filters have similar construction, they still differ significantly. The main difference between them is the media they use for filtration process. For example, the carbon filter contains a large layer of activated carbon, while the sand filter has collection of sand with different particle sizes.

The carbon filter is perfect for removing whatever chlorine that was leftover after the water passes through the sand filtration stage. It is also great for removing molecular organic particles or elements that have managed to escape the previous stages of filtration. Activated carbon is great for eliminating any odors, colors, pesticides, or even organic components that may be present in water.

Bottom Line

Even though Sand filters are placed before activated carbon filter media, they still need to be cleaned and maintained in the same way. Factors such as the composition and pollutant concentration in the water, the airflow duration, and the water temperature and humidity affect the expectancy and efficiency of the filter media. For any inquiry related to sand and carbon filter media for desalination, get in touch with us at info@keiken.es.