Study Of Solidification And Stabilization Treatment Of The Arsenic Waste Residue

Though the raw materials structure of the sulfuric acid production in our country has been adjusted greatly in the past ten years, the waste solid produced in the process of metallurgical industry contains sorts of noxious substances, such as As, Cd, Cu, Pb, Zn, Cr, Hg, F. 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 must be filleded with the technology of solidification and stabilization. They contain lots of chemicalgypsum and cementing materials which could be chemical combination with fly ash and mineral waste residue. The arsenic waste residue could be filled securely under the technology of solidification and stabilization.Based on the full knowledge that the arsenic waste residue and fly ash and the mineral waste residue 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 mineral waste residue and waste fly ash as raw materials, the article started with studying the properties of the active materials according to the basic principles of cementing material. The additional medicament can act as the effective activator to the mineral waste residue and fly ash.The article made a conclusion on the components system and the optimum mixture proportion of cementing materials, the arsenic waste residue: cement: the mineral waste residue: fly ash: broken stone is 1:0.4:0.2: 0.2:0.2, with others additional medicament, w/s is 0.4. 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 maintainment mode are determined by different experiments. The best way is to put the sample into the natural condition for 24 hours,. then it will be maintained under the natural condition to the 28th day after being maintained in the 24 centigrade box for 15 days. The solidified strength of the sample is about 10Mpa,which could reach the correlative criterion of the fill. 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 techniques in this subject is economical and effective, they can really realize the finally safely handling of dangerous solid waste such as arsenic waste. The subject can offer reliable basises and guidances for the industrialization of these techniques, it can offer references for Daye Company to improve the original craft, and has great social, economic and environmental meanings to study and develop high-efficient arsenic waste residue technology.