Surface Water Treatment Systems

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Clarifiers play a crucial role in water treatment wherever the concentration of suspended solids in raw or wastewater is elevated. Found in almost all treatment plants, clarifiers typically feature circular or sometimes rectangular designs.

The operation of clarifiers is based on the principle of gravity settling. Under the quiescent conditions established in the clarification zone, heavier suspended solids settle within the clarifier. The settled solids are then directed towards the center well, which is designed for the collection of sludge, facilitated by the movement of scraper blades. This process allows for the separation and removal of suspended solids from the water, contributing to the clarification and purification of the liquid.

Filtration has been a water purification method employed for thousands of years to reduce the levels of dirt, rust, suspended matter, and other impurities in water. The process involves passing the dirty input water (influent) through a filter media, where impurities are retained within the filter material. The mechanisms for removing impurities can vary based on the nature of impurities and the specific media used.

Over time, some filtration systems have undergone significant changes in equipment, while others, like depth filters, have seen minimal alteration. As our understanding of the fundamental physical and chemical mechanisms involved in filtration has improved, there has been a refinement in the removal of impurities from water. Filtration systems not only remove particulate matter but, due to the extensive surface area of filter media, they can also drive chemical reactions leading to the removal of various contaminants. These advancements have allowed for the optimization of water purification processes over the years.