Lead smelting primary smelters

Lead is also produced in a blast furnace using coke as the primary reductant. Much like the iron blast furnaces, the off-gases from the smelting of lead oxides will primarily contain CO and CO2. This gas is recycled back to the blast furnace to use the reducing power of the CO and the heating value otherwise lost. This helps to reduce the total amoimt of carbon that would be needed to produce lead. In many smelters, galena (the natural mineral PbS) is the feedstock. The... 

Similar to the rest of the world, the traditional primary smelters also tend to treat an increasing amount of lead scrap in their primary lead smelting operations. 

The main driving force for this development is the overall process improvement to be gained by removing many internal secondary recycle streams, thereby freeing the QSL smelter for primary lead smelting activities. This smelter is the third Ausmelt technology smelter installed at Korea Zinc s Onsan complex and will commence operations in the second half of... 

It is of interest to note that during 1976 the arithmetic mean lead content of lead works emissions examined by HM Alkali Inspectorate was 0.011 g mT. It was also noted in the report of the Inspectorate [7] that at the Avonmouth primary lead-zinc-cadmium smelter of Commonwealth Smelting Ltd. (with a capacity of 40 000 tonne of lead annually), emission of lead was about 4 kg h in 1976, compared with a consent limit of 5.4 kg h . ... 

Primary smelters are often associated with major mining operations, bnt are nsnaUy centrally located in major industrial centres. Because of the environmental issues associated with lead smelting sites in the past, it will be very difficult in the future to obtain licences for the construction of new... 

Secondary lead smelting tends to be localised around major population centres and the supply of waste batteries, due to the relatively high cost associated with the transport of used batteries. The secondary smelting technologies used are also suited to relatively small-scale operations in comparison with primary smelters, which can benefit significantly from the economies of scale. 

Moriya, K, 1989. Achievement in lead smelting during a quarter century at Mitsubishi-Cominco s Naoshima smelter, in Proceedings Primary and Secondary Lead Processing Symposium, Halifax, August, pp 71-86. 

Clearly actual capital costs for each individual project partly depend on chosen scale, process technology and a range of site-specific factors. However, on the basis of recent or planned new greenfield developments, capital costs for new primary lead smelting focilities can be reasonably estimated at between US 2-3000 per annual ton of capacity, with new secondary lead capacity about one half to two-thirds of this. Where smelter refits or modifications are involved, and infrastructure already exists, the capital cost will clearly be much lower. 

A number of companies in Europe (Metallgeseiischafc, Metaleurop, Nuova Samim, for example) have important secondary interests in addition to primary smelting activities, and have been actively developing these. So too has MIM, through ownership links with Britannia Refined Metals in the UK. In North America, while several primary smelters use lead scrap feed. Doe Run s Buick secondary plant (opened in 1991) was the first example of direct primary producer involvement in recycling facilities. Emissions from this plant are apparently 60 per cent less than at traditional secondary lead facilities. 

The principal U.S. lead producers, ASARCO Inc. and The Doe Run Co., account for 75% of domestic mine production and 100% of primary lead production. Both companies employ sintering/blast furnace operations at their smelters and pyrometaHurgical methods in their refineries. Domestic mine production in 1992 accounted for over 90% of the U.S. primary lead production the balance originated from the smelting of imported ores and concentrates. 

Lead compounds are emitted from both the sintering and smelting processes during primary lead production (Chapter 5). Measurements both within the stack and the atmosphere in the vicinity of primary lead smelters indicate emission of lead primarily as PbS04 and Pb0 PbS04. 

These two stages may be within the one smelting site or may be two separate businesses, with crude lead bullion being the traded intermediary. Traded lead bullion is commonly derived from the treatment of primary concentrates, but can also be lead bulUon produced from secondary sources. Secondary bullion generally contains much fewer impurities. As an example, ISF smelters do not usually include lead refining operations and consequently sell their crude lead bullion to a refinery. The commercial terms for the sale of lead bullion are typically as follows ... 

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