The principle of “shallow sedimentation” originated from the use of oblique tubes in medicine to accelerate blood sedimentation. In 1904, Doctor Hazen putted forward the theory of “Shallow Pond”. This is Tube settler’s working principle. Simply speaking, Many tube setters were be seted up on the despositing area,when sewage containing particles flows along the surface of the tube setter, the particles will naturally sink under the influence of gravity.Tube settler is a very significant unit of clarifiers in the water and wastewater treatment plant. Tube settlerimproves effluent water quality and results in a significent decrement in plant costs. Tube settler is usually made of PP and PVC