Rectangular clarifier provides a layout friendly option in the primary treatment for water & wastewater applications. Rectangular clarifier is used for the handling of sludge removal. They provide minimum dead space between the units, and these units can be placed on the common wall. The mechanisms involved with rectangular clarifier can be provided with non-metallic components including chain, sprocket and scrappers. They ensure easier erection due to the decreased weight and also provide longer life. These scrappers are driven through the chains on both ends of the tank. 

The rectangular clarifier can be used with traveling bridge scrappers. The scrappers are mounted on the bridge that moves on the steel rails along the length on the top of the tank wall. A drive is used for the bridge, which takes the electrical supply through an independently supported festooning cabling system. They can be placed either above the tank wall or along the tank according to the requirement. The scrapper moves the settled solids towards the discharge section in the forward movement. During the reverse movement of the bridge, the scrapper is lifted up to the water level and then it moves the floating scum in the reverse direction for further disposal.

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