Method for preparing ceramsite by utilizing dried sludge and burnt fly ash

The invention discloses a method for preparing ceramsite by utilizing dried sludge and burnt fly ash, belonging to the technology of reduction, harmless treatment and disposal and recycling of dangerous solid waste. The method comprises the following steps of: drying dewatered sludge with moisture content of 75-85% to obtain dry sludge; crushing the dry sludge, and then screening; mixing the screened dry sludge, burnt fly ash and bentonite uniformly according to a certain proportion to obtain a mixture; injecting the mixture into a powder pressing machine for extruding and forming to obtain a blank; preheating the blank at certain time; roasting the blank at high temperature at certain time; and naturally cooling to room temperature to obtain a ceramsite product. Simultaneous reduction, harmless treatment and disposal and recycling of two dangerous wastes of the burnt fly ash and municipal sludge are realized with the method, and the produced ceramsite product conforms to the standard of toxic leaching and meets the requirement of lightweight aggregate of buildings. The method has the advantages of simplicity in process, less investment, low operating cost, large required quantity of the produced ceramsite products and the like.