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Zinc Dust and Compounds
Published in Frank Porter, Zinc Handbook, 1991
Zinc Dust in Electrolytic Zinc Refining. Zinc dust is used in the preliminary stages of the electrolytic refining of zinc itself. Zinc ores are roasted to remove sulphur compounds and are then treated with sulphuric acid to produce an impure solution of zinc sulphate. If attempts were made to electrolyse this material as it stood, the metallic impurities in the solution would prevent the formation of a sound and pure deposit of zinc. The addition of zinc dust precipitates all those metals which are below zinc in the electrochemical series, and after filtration, pure zinc can be deposited from the solution. The presence of copper among the impurities speeds up precipitation and small quantities of copper sulphate solution are added prior to treatment with zinc dust where the ore being treated is very low in copper. The quantities of zinc dust used vary from plant to plant according to the nature of the raw material, and the purity required in the final metal.
Alternative Energy Sources for the Mineral Sector
Published in Sheila Devasahayam, Kim Dowling, Manoj K. Mahapatra, Sustainability in the Mineral and Energy Sectors, 2016
Sheila Devasahayam, Raman Singh
In Australia, and Tasmania in particular, the electricity needs of remote mining operations that lacked access to coal prompted hydroelectric development, for example, in the remote tin mining operation at Mt Bishoff, Mt Lyell Mining (9 MW scheme) and Railway Company copper mine in Queenstown, and the Pioneer Tin Mining Co. in eastern Tasmania. The Complex Ores Company built a 49.1-MW scheme at Waddamana for their new electrolytic zinc refining process requiring a low-cost source of large amounts of electricity (Harris, 2011).
Renewables—The Future’s (only) Hope!
Published in Anco S. Blazev, Energy Security for The 21st Century, 2021
As such, it is in limited quantities, spread all over the world. The principal sources of silver today are ores of copper, copper-nickel, lead, and lead-zinc. The silver metal is produced as a byproduct of electrolytic copper refining, gold, nickel, and zinc refining, and from lead ores containing small amounts of silver. Commercial-grade fine silver is at least 99.9% pure, and purities greater than 99.999% are available, some of which are used in the solar industry.
ASM-VoFDehaze: a real-time defogging method of zinc froth image
Published in Connection Science, 2022
Wenhui Xiao, Zhaohui Tang, Ce Yang, Wei Liang, Meng-Yen Hsieh
According to Figure 1, the main light source of the froth image video comes from the light-emitting diode installed at the top of the box. Due to the physical and characteristics of the froth, the froth that adheres to the mineral particles automatically burst after a certain period under the action of gravity. As a result, the mineral content on the top of the froth slowly decreases until only a water film is found at the end, which bursts immediately. The reflection of the light source at the water-air interface is total reflection, so in the froth image we obtain, bright spots are seen at the top of the froth. In the non-fog state, the brightness of the froth highlights is extremely high and is basically pure white. In the foggy state, the froth highlights are shrouded in haze, which is grey and foggy. In the image of the flotation froth with fog, the bright spots on the froth reflect the atmospheric light value of the corresponding area of the image. In this section, the froth image is first greyed out, and then the threshold is set to extract the highlight pixels of the froth image. The average value of these pixels is taken as the estimated result of the atmospheric light A value. Many experiments have proved that the estimated results of atmospheric light A value in different flotation cell froths are different. The atmospheric light A of the zinc-roughing tank is approximately 220, the zinc-refining tank is approximately 175, and the zinc-scavenging tank is approximately 190. The result can effectively reflect the real atmospheric light conditions and restore the texture details of the fog-free image.
Subcellular distribution, chemical forms, and physiological response to cadmium stress in Hydrilla verticillata
Published in International Journal of Phytoremediation, 2019
Guoxin Li, Qingsong Li, Lei Wang, Guoyuan Chen, Dandan Zhang
The pollution of aquatic ecosystems by heavy metals has increased considerably in recent years due to their toxicity and accumulative behavior. In particular, cadmium (Cd) is a hazardous pollutant in various ecosystems and to human health (Kováčik et al. 2017a). Various serious health risks are associated with Cd intake, including lung cancer, renal disturbance, osteoporosis, cardiovascular disease, and hypertension. Furthermore, Cd is carcinogenic, embryotoxic, teratogenic, and mutagenic (Vimalraj et al. 2017). The main source of Cd contamination is wastewater from industries, such as electroplating, pigments, plastic and battery production, and zinc-refining or mining (Lima et al. 2013).