Study On Curing / Stabilization Of Copper Smelting Sludge

Copper metallurgical sludge resulted from the waste acid treatment by using the lime-iron salt technology in the copper metallurgical plant contains arsenic and other heavy metal ions, mainly including CaSO4·xH2O and the arsenic content is about5%～15%, though such heavy metal contents exist in the form of hydrate, sulfate, arsenate, arsenite and other compounds. And some of them tend to be unstable and permeable in the process of soil and water transportation, and in turn is highly detrimental to the eco-environment, this kind of sludge treatment need to be solved.In this article, through analysis of the sludge characteristics and its formation mechanism, the calcium sulfate ingredients in the sludge are obtained with the ordinary slag Portland cement, fly ash gel material such as potential activity characteristics, and explore its use. By studying gelling material such as cement, fly ash on the effect of sludge solidification and gypsum-water hardening mechanism of fly ash gel material, optimal proportion of colloid materials, copper sludge:cement: fly ash:sand=45:36:9:10; according to the principle of gelled material and environmental science, choose a small amount of composite curing agent A to inspire gelled material hydration activity, the molding pressure of25MPa, water/cement ratio of0.25. Curing mode are determined by different experiments. The best way is to put the sample into the standard curing fur24hours, then to the natural condition. Different factors which influencing the properties of the cementing materials ate investigated. With advanced testing methods of XRD, SEM, etc, the solidifying mechanism and the microstructure of products solidified are analyzed.The experimental results show that the solidified samples strength up to18.9MPa, the leaching of the arsenic ion from the sample is for2.55mg/L lower than below (GB5085.3-2007) standard in5mg/L, natural radioactive conforms to the national standard of the People’s Republic of China-building materials radionuclide limited (GB6566-2010). After solidification/stabilization treatment of copper sludge can not only achieve the purpose of prevention and control of pollution, and the rubber of condensed used with cement and other raw materials can be used in the production of building wall products, this paper studies the scheme not only solve the problem of environmental pollution but also has a certain economic benefits.