Stormwater tank

polyethylenecylindricalin-ground

The first rainwater treatment plant is made with monolithic polyethylene tanks, designed to be buried and constructed using rotational molding with a constant thickness. The system consists of four distinct elements: Stormwater Overflow Chamber: Suitable for the separation of first rainwater. Storage Tank: Sized to retain the first 5 mm of rain that falls on an impermeable surface. Calm Chamber Coalescence Oil Separator: To remove oils and fats present in the accumulated water. A submersible pump with a recessed impeller is installed inside the storage tank, which lifts and transfers the accumulated effluent to the next phase of oil separation. The effluent exiting the system can be discharged into surface water or sent for further treatment stages. The structures are equipped with vents, inlet and outlet pipes, and inspection and maintenance caps. Technical features Function and Use The plant is used for the treatment of first rainwater from roads, yards, and parking lots. In practice, the first rainwater is separated from the subsequent (second rain) and sent to the treatment unit (grit chambers, oil separators, etc.) via an underground storage basin, with sufficient capacity to contain the water volume of the first 5 mm of rain that falls on the runoff surface of the plant. The basin is preceded by a separator chamber with an internal weir, over which the second rainwater flows when the water level in the basin reaches the weir threshold.