Sludge belt press

The sludge belt press NPF type is recommended for medium-small sludge treatment plants. Generally it is installed downstream the sludge treatment lines and consists of a frame with two stiffed lateral sides suitably connected to each other, storage and drain tanks for the filtered water, two joined belts through which the sludge to be dewatered passes, a roller assembly used to drain and press the sludge, belt puller, belt centring and transmission rollers, a washing system with nozzles for each belt and a variable speed drive. The roller assembly includes a big diameter roller for the drain, a low pressure roller and six high pressure rollers two of which also for transmission, two belt pullers, two belt centring rollers, three return rollers and one roller for the inlet to the working area. The sludge enters the hopper of the belt press through a delivery piping and is distributed on the lower belt by a baffle; successively it meets the upper belt and helped by the inlet roller is conveyed to the pressure zone. The sludge goes in contact with the drain roller which has a big diameter and allows a slight compression of the sludge. The sludge is then compressed at an increasingly higher pressure up to the high pressure zone. After the sludge evacuation, the two belts are washed for the residual material removal. The variable speed drive, which transmits the motion to the two transmission rollers, allows the belt speed adjustment according to the type of sludge to be treated. The main characteristic of this equipment lays in the compactness and completely closed execution which avoids any water sprays and meets the hygiene requirements in the working place. The standard type of construction is with hot dip galvanized carbon steel frame while the other parts in contact with the water, the tanks and all the rollers are in stainless steel. Moreover, the transmission rollers and the belt centring elements are covered with a rubber layer in order to ensure the friction required for transmission and control. On request it is possible the construction with particular protections or completely in stainless steel.