An Experimental Study On A Compound Sludge And Silt Haydite Sintering

Sludge is a type of solid wastes and produced during the process of sewage disposal, which can do great damage to the environment. With the rapid development of city construction, more and more sludge is produced. Sludge contains a lot of poisonous and harmful substances and will induce serious environmental issues without proper disposition. Although silt is less harmful compared with sludge, it is large in quantity and is difficult to recycle in solid wastes. Therefore, it is essential to develop a technique for sludge and silt disposal.In this thesis, the physical and chemical properties of sludge and silt are introduced. Experiments are conducted to study the effects of the conditioner, the pressure and time taken in mechanical dewatering, and the microwave and air drying on the dehydration of sludge and silt. Based on these experiments, an economical and feasible dewatering scheme of compound sludge is proposed. Considering the haydite sintering technique, compound sludges with different mass ratios of sludge to silt are analyzed. Experimental results show that, when the mass ratio of sludge to silt is in the range of5%and15%, the preheating time is from20to30minutes under a temperature of300℃, and the sintering time is10minutes under a temperature of1120to1150℃, the physical properties of haydite, such as the volume, bulk density, cylinder compressive strength, and apparent density, all meet the relevant standards of building materials and therefore it can be applied to practical engineering.