rear window>near怎么读
extended火法炼铜流程英文版
海外考试中心earth dayCopper is one of the comparatively few metals found in the "native" metallic state.Most cooper ud today is extracted by smelting.Sulfide ores are ground and then require a roasting process to reduce sulfur and arnic content.The fume given off in the process is destructive to the environment surrounding the smelter,so that collection of the fume is required.The copper oxide also contains gold,silver,and other impurities,which are later removed.
The copper ore is then smelted in a reverberatory or electric furnace to produce an impure alloy called matte.
新东方英语口语班Air is then blown through the molten matte in a converter to remove any iron and remaining sulfur to produce a refined copper known as "blister" copper.There are two steps in the converter.first is slag-forming step,and the nest is copper-forming step.
Further refinement is necessary to produce copper for electrical and other us,which is do非关风月 只为真心
republique
ne by electrolysis.At the electrolysis process,the cathode,or the starting sheet is made of pure copper.And the anode is made of some metals which have a more negative standard electrode potential than copper such as PGMs.The electrolyte is copper sulphate and some sulfuric acid.Electrons move from the cathode to the anode through the electrolyte,and the copper irons move from the anode to the cathode through the conductor.It is at this stage that impurities such as silver are collected at the bottom of the tanks and removed from the sludge by a parate process.Copper 99.9 percent pure is produced by the electrolytic process.baidu翻译