What is the main function of a sand filter in water treatment?

The main function of a sand filter in water treatment is to remove solids from the water. Sand filters operate by allowing water to pass through layers of sand, which physically traps and retains particles, such as dirt, sediment, and other particulates. The effectiveness of this filtration process depends on the size and configuration of the sand grains, which create spaces that can capture various solid contaminants as water flows through.

While other options involve processes related to water treatment, they pertain to different types of filtration or treatment methods. For instance, removing tastes and odors typically involves activated carbon filters or chemical treatments rather than mechanical filtration like sand. Dissolved materials usually require advanced processes such as reverse osmosis for removal, as these substances pass through sand filters. The removal of bacteria often relies on additional disinfection methods, such as chlorination or ultraviolet light, instead of just sand filtration. Therefore, the primary role of a sand filter is centered on the effective removal of solids from the water.