Bevel-helical speed reducer B3 ards For details on the shafts see Chapter B3-SH18A

Flender/Flender Gear Units/Bevel-helical speed reducer B3

obtained, .. primary lead concentrates and flue dusts can be processed into lea$bu/lion according to the QSL process, the final sla contains 3% Pb. Technically useful experience was gained as regards the qualit and serviceyife of the refractory masonry, the operation of waste heat boiler with dust-rici gases, and the measurement technique and materials sectors. The main goal of the pilot project was to prove that the QSL process is an ecologically compat- ible and energy-saving process for the production of lead bullion. Both goals were completely reached. In comparison with conventional lead smelter based on 1,0 tpa lead bullion, the lead emission has been reduced by 7V0,from approx.4 Pb/ lead bulliontoap rox 8 Pb/ lead bullion,and the SO2 emissions have been reduced by9Y0,from approx.4 tgSO,/ lead bullion to 2.6 kg SOJt lead bullion. The specific energy consumption was reduced by So%, from roughly 2,0 1 O3 kcal/ lead bullion to roughly 1,0 1 O3 kcal/ lead bullion. demonstration of the technical applicability of an innovative metallurgical process requires not only an adequate size for upscaling, but also several months of continuous trial operation. In addition, the economic efficiency can only be confirmed after sufficient continuous opera- tion under optimum process conditions. At present, 5% of the lead production in the Western hemisphere is based on secondary raw materials and waste roducts. Due to the process, only sulphur-free or low-sulphur raw mater- ials can be processeh secondary lead smelting works, because there are no facilities (installa- tions for production of su1phuricacid)for recycling the sulphur dioxide (SO,) produced. There- fore, all sulphurous residues must be processed in smelters with subsequent sulphuric acid production, .. in primary lead smelting works. Since the development and trial operation of the QSL process are aimed at the future substitution of conventional rimary lead smelters, it must be ensured