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Heavy Metals
Published in Abhik Gupta, Heavy Metal and Metalloid Contamination of Surface and Underground Water, 2020
Nickel (Ni) with an atomic number of 28, an atomic weight of 58.693, and a density of 8.90 g cm–3, is classified as a heavy metal. Pentlandite [(NiFe)9S8], a sulfide mineral, is the principal ore of nickel. Nickel is extensively used in a large number of alloys for different purposes. For example, nickel–chromium–iron alloys have corrosion-resistant properties and are, therefore, used in corrosion-resistant equipment, applications, and utensils. Nickel–copper alloys such as monel metal are used for minting coins, and in several types of machinery and equipment. The other main uses are the manufacture of magnets and catalysts (nickel–aluminum alloys), heating elements, gas turbines and jet engines (nickel–chromium alloys), and jewelry (nickel alloys with precious metals). Nickel and its alloys are also used in electroplating, arc-welding, and the manufacture of magnetic tapes, computer equipment, surgical and dental prostheses, nickel–cadmium batteries, paint pigments, molds, and others (Encyclopaedia of Occupational Health and Safety 2012).
Arctic mining in Raglan
Published in John E. Udd, A.J. Keen, Mining in the Arctic, 2020
In general, the majority of ore mineralization consists of Pentlandite (main Ni source) and Pyrrhotite (iron sulfide) with accessory chalcopyrite (copper). The ore is typically located within ootwall embayments that appear to have been generated by thermal erosion. Minor but significant quantities of cobalt, platinum and palladium are also associated with the ore.
Minerals
Published in F.G.H. Blyth, M. H. de Freitas, A Geology for Engineers, 2017
F.G.H. Blyth, M. H. de Freitas
In the important pyrrhotite ore-deposits at Sudbury, Canada, the mineral is accompanied by the nickel sulphide pentlandite (Fe,Ni)S. These deposits yield the greater part of the world’s nickel supply; the ore-bodies occur at the margins of a basic igneous mass (gabbro or norite).
Workability, strength and microstructural properties of ground ferronickel slag blended fly ash geopolymer mortar
Published in Journal of Sustainable Cement-Based Materials, 2022
Jhutan Chandra Kuri, Md. Nabi Newaz Khan, Prabir Kumar Sarker
Ferronickel slag (FNS) is an industrial residue discharged as a by-product of the manufacturing process of ferronickel alloys [10]. The main sources of nickel are pentlandite, garnierite and laterite ores. The ore is usually smelted in an electric furnace to produce ferronickel. After completion of the primary reduction operation at a temperature between 700 °C and 800 °C, the nickel ore is melted at temperatures ranging from 1500 to 1600 °C. The molten by-product known as ferronickel slag is cooled by air or water. The air-cooled FNS is usually gray and lumpy, whereas the water-cooled FNS consists of dark green granules [11]. The principal constituents of FNS are Si, Fe and Mg, in a combination of crystalline and noncrystalline minerals [12]. The physical characteristics of water-cooled FNS are suitable to utilize as fine aggregate in concrete. Several investigations were carried out on the utilization of FNS as an aggregate [13,14]. Furthermore, since FNS has a notable content of amorphous silica, ground FNS (GFNS) shows reactivity when mixed with cement or an alkaline liquid [15–18]. Komnitsas et al. [19] investigated the reactivity of GFNS by leaching test. The authors found that high amounts of Si and Al dissolute in the leached solution, which indicated a higher reactivity of GFNS. Yang et al. [20] investigated the reactivity of different types of air-cooled and water-cooled GFNS by using the dissolution experiments. It was reported that the air-cooled GFNS shows lower reactivity compared to the commonly used source materials, such as fly ash and blast furnace slag. On the other hand, water-cooled GFNS showed high reactivity.
The Direct Leaching of Nickel Sulfide Flotation Concentrates – A Historic and State-of-the-Art Review Part I: Piloted Processes and Commercial Operations
Published in Mineral Processing and Extractive Metallurgy Review, 2023
Nebeal Faris, Mark I. Pownceby, Warren J. Bruckard, Miao Chen
A list of economically important nickel sulfide and arsenide minerals, as well as common sulfidic gangue in nickel sulfide deposits is presented in Table 3. Pentlandite is the most important nickel sulfide mineral and commonly occurs with pyrrhotite and chalcopyrite. Other nickel sulfides listed in Table 3 can be important where alteration has taken place. Violarite is a supergene alteration product of pentlandite and typically occurs in pyrite-violarite and transition zones above the primary zone (massive pentlandite-pyrrhotite ore) (Marston et al. 1981; Nickel, Ross, and Thornber 1974) and can be economically important during the mining of some massive nickel sulfide ores. Millerite forms as an alteration product of pentlandite (Bide, Hetherington, and Gunn 2008; Holwell et al. 2017) and is an important nickel sulfide mineral in some deposits such as Mt Keith, Black Swan and the Otter Shoot, Kambalda (Dowling et al. 2004; Grguric et al. 2007; Keele and Nickel 1974). Niccolite and gersdorffite can occur in nickel sulfide deposits as a result of hydrothermal alteration; their presence in nickel concentrates is undesirable due to the deleterious effects of As during smelting and typically requires dilution to an acceptable level by blending with low As concentrates (Grguric et al. 2007). Pyrrhotite, an iron sulfide, is the primary gangue sulfide that occurs in nickel sulfide deposits though it typically contains Ni, either in solid solution or as fine pentlandite intergrowths (Rezaei et al. 2017; Toguri 1975). Typically, the Ni concentration in solid solution in pyrrhotite is 0.4–0.6% and the presence of micron-size inclusions of pentlandite can raise the nickel content even higher (Rezaei et al. 2017; Toguri 1975). Hence during beneficiation of nickel sulfide deposits, nickel loss due to pyrrhotite rejection is inevitable.