808results about How to "Less sludge" patented technology

The invention relates to a method for screening and dewatering urban sludge efficiently. Sludge in an urban wastewater treatment plant is conveyed to a self-synchronizing translation elliptical vibrating screen for dewatering and screening, and then the urban sludge is dewatered efficiently by a method of a combination technique of chemical agent concentration, liquid tempering and box-type filter pressing. After the method detects the concentration of the sludge automatically, dosing amount is calculated and medicament is automatically added to realize automatic dosing; and a filter pressing and dewatering process can meet the requirements of the modernized wastewater treatment plant, the full automatic operation of a system can be implemented by the control of a PLC system, and operations, such as charge-in, the movement of a filter board, segmental filter pressing, positive and negative aeration, filter cloth flushing, unloading and the like can be completed by the remote control of the PLC so as to relieve the labor intensity of workers. Because of the successful adoption of a segmental filter pressing technique of low-pressure filtering and high-pressure extrusion, the operating efficiency is 2 to 3 times that of the conventional plate-and-frame filter press; and after the sludge is dewatered, the water contents of mud cakes of the urban sludge screened and dewatered by the method are reduced to below 60 percent.