Stablization/solidification Of Non-ferrous Metallurgy Sludge

The waste water produced in the process of metallurgical industry contains sorts of noxious substances. Such as Cu, As, Pb, Zn, and Cd. They will be turned into deposition mingled with lime; the component of the deposition is complex within various poisonous and harmful materials. If they are piled untreated for a long time, they will not only occupy the farmland, but also pollute groundwater, farmland, and human body health and ecosystem environment. They contain lots of chemical gypsum and cementing materials, which could be used to produce low-level building materials, the technology of solidification and stabilization could not only make the waste innoxiously, but also turn them into resource.The application of fly ash and slag to solidify sludge is not only advantageous to solving the question of environment protection and energy conservation, but also comes to the new style which take environmental materials as main body, moreover it plays a positive role in improving the function of building materials especially the materials durability, extending the variety and scope of building materials commonly used today.Based on the full knowledge that sludge and fly ash and slag have differences in their ingredient and potential activity, The article has important practical significance in analyzing the specific property and investigating their utilization. Using special industrial sludge and waste fly ash and slag as raw materials, the article started with studying the properties of the active materials, and choose lime hydrate as the alkali activator, according to the basic principles of cementing material. The lime can not only neutralize acids in sludge, but also act as the effective activator to the sludge and fly ash.The article made a conclusion on the components system and the optimum mixture proportion of cementing materials, the sludge: slag: fly ash: cement is 25 ." 30 I 30 I 15,with 8% additional lime, w/s is 0.183. Many kinds of medicines are also investigated with a medicine we named it A which could reach the best result with 0.06% of the weight of sludge, the molding pressure is 25Mpa, Different factors which influencing the properties of the cementing materials are investigated. With advanced testing methods of XRD,SEM, etc, the solidifying mechanism and the microstructure of products solidified are analyzed.Pretreatment method and curing mode are determined by different experiments. The best way is to put the sample into the steaming box for 24 hours, then to the natural condition. The solidified strength of the sludge is 11.8Mpa,which could reach the correlative criterion of the construction The leaching of the heavy metal iron from the sample is lower than the figure which is required in the identification standard for hazardous wastes- Identification for extraction procedure intoxicity. The solidifying and stabilizing is energy saving and it won't bring the second pollution, the result has great value of application and social benefits.