Smelting primary

Because of the high tin content of the slag, a primary smelting is used to effect a first separation, followed by a second stage to process the slag and hardhead from the first smelting plus refinery drosses. 

In primary smelting, carbon (in the form of coal or fuel oil) is the reducing agent. During heat-up, carbon monoxide is formed by reaction with... 

Primary smelting can be carried out in a reverberatory, rotary, or electric furnace. The choice depends more on economic circumstances than on technical considerations (3). Thus, in the Far East, reverberatory furnaces fired with anthracite coal as the reductant were and still are widely used. 

Primary smelting and refining of copper 3334 Primary production of aluminum 3339 Primary smelting and refining of nonferrous metals, except copper and aluminum 3341 Secondary smelting and refining of nonferrous metals... 

Primary smelting, of tin, 24 787-788 Primary timber products, 26 361-363 Primary uranium minerals, 25 396 Primary vulcanization accelerators, 21 797 Primary wastewater treatment, 25 888 Primers, 18 67... 

Tin is produced from oxide by heating at high temperatures with carbon. Small amounts of limestone and sand are added to coal for this reduction and to promote removal of impurities. Primary smelting is carried out in a rever-baratory furnace at a temperature between 1,200 to 1,300°C. Electric arc furnaces also are used. The molten tin collected at the bottom is cast into slabs. The slags are resmelted at a higher temperature, up to 1,480°, in the same type of furnaces to recover more tin that is combined as silicates. 

Spurgeon DJ, Hopkin SP. 1996. Risk assessment of the threat of secondary poisoning by metals of predators of earthworms in the vicinity of a primary smelting works. Sci Total Environ 187 167-183. 

TABLE 13.1 Major World Producers of Copper Concentrates and Primary Smelted Copper"... 

Sandifer, R.D. (1996) The effects of cadmium, copper, lead and zinc contamination on arthropod communities in the vicinity of a primary smelting works. PhD thesis, University of Reading, UK. 

Spurgeon, D.J. and Hopkin, S.P. (1999) Seasonal variation in the abundance, biomass and biodiversity of earthworms in soils contaminated with metal emissions from a primary smelting works. Journal of Applied Ecology, 36, 173-183. 

Production of matte. A few secondary smelters form a matte, a high sulfide material generally containing arsenic, to remove unwanted elements. This process is common in primary smelting. 

Analysis of primary lead reveals higher impurity levels, particularly for valuable elements such as silver and gold. The removal and recovery of these elements is an important and valuable process in primary smelting. 

Primary smelting and refining of nonferrous metal (except... 

Primary smelting in either a Flash Furnace or an Ausmelt TSL... 

The capacity distribution of primary smelting capacity is shown in Figure 1.5. The vertical axis represents cumulative capacity of plants above a given plant size, as given by the horizontal axis. 

The number of primary and secondary smelters within a given size range is illustrated in Figure 1.7, which shows the significant difference in numbers and in plant capacities. The scale of these plants also has an impact on the technologies used for secondary smelting in comparison with primary smelting, and the most common approach is the use of the short rotary furnace. 

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