Cementation mineral processing

Applicability Most hazardous waste slurried in water can be mixed directly with cement, and the suspended solids will be incorporated into the rigid matrices of the hardened concrete. This process is especially effective for waste with high levels of toxic metals since at the pH of the cement mixture, most multivalent cations are converted into insoluble hydroxides or carbonates. Metal ions also may be incorporated into the crystalline structure of the cement minerals that form. Materials in the waste (such as sulfides, asbestos, latex and solid plastic wastes) may actually increase the strength and stability of the waste concrete. It is also effective for high-volume, low-toxic, radioactive wastes. 

Cementation the process of precipitation of a binding material around grains or minerals in rocks. 

Refractories made using aluminas are used in the iron and steel, chemical and petroleum, ceramics and glass manufacture, minerals processing (cement, lime, etc), pubHc utflities, waste incineration, and power generation industries. 

Mineral Processing. This older application dating back to the 1950 s is used to decompose or purify ores through calcination or the roasting and pre-reduction of ores. Fluidized bed processing is also used in cement manufacture. 

Other appUcations include lined pipes to transport acidic wood chip slurries in pulp and paper mills, as well as mixtures of sand, tailings, cements and water for backfiUing shafts and drifts in ore mines. Furthermore, alumina protection is applied to transport pipes of sand tailings in Canadian tarsand extraction facilities in northern Alberta, and for the lining of cyclones to clean and classify ores in aU flelds of wet mineral processing (Foster, 1996). 

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