Raw materials storage and blend 

    Raw material ore into the factory, then transfer into concentrate warehouse, there are various of underground storages, separately store raw materials such as lead concentrate, limestone, coal, coke, crushed aggregates that got from sintering and smelting process, soot etc. There is a grab bucket crane in the concentrate store for blending and feeding. To meet the requirements of pelleting,flux and other material particle size must less than 3mm.There is a feeding hopper on the concentrate store, the volume of each hopper is 6m3,feeding by measuring. All the materials are sent toФ1200×5000 drum pelletizer by belt conveyor, then directly pelletize with water. Mixing granules are sent to sintering system by belt conveyor. 

    Sinter roasting 

    Sinter roasting is the preparatory work before reduction smelting, its main purpose is to remove most of sulfur of raw materials, make the galena to be lead oxide and output hard porous agglomerate that meet the requirements of reduction smelting of blast furnace. 

    The basic technological process of sinter roasting: the mixture prepared enters into belt-type sinterer evenly by feeder, through ignition and blast, the metal sulfide of mixture oxidizes(mean roasting),produce metal oxide and sulfur dioxide, release large quantities of heat and make the oxidation reaction continues. At the same time, making the low melting point material (silicate etc.) in a state of cementation and mutual bonding into pieces. Agglomerate through crusher and screening machine, big material is sent to stock bin of furnace smelting system, powder returns for blending. 

    During the process of sinter roasting, most of galena oxidized to lead oxide; copper, zinc, iron sulfide partial oxidation, the rest remains in agglomerate; the oxide of arsenic and antimony is easy to volatilize, part of them enters into soot; gold and silver is hard to be oxidized and remains in agglomerate, the calcium carbonate of material dissociate calcium oxide and carbon dioxide.  

    Blast furnace reduction smelting 

    The purpose of Blast furnace reduction smelting is to make the metal oxide in agglomerate can react with reducing agent in the heat, restoring the metal. The reduction smelting of lead blast furnace uses coke as fuel and reducing agent, it has two main processes: first, the burn of carbonaceous material; second, react with metal oxide (most of is lead oxide, such as lead oxide, lead silicate, lead ferrous acid etc.)that with oxygen affinity is smaller, reducing to get crude lead, precious metal such as gold, silver etc. all enriched in crude lead. Gangue’s component such as SiO2, FeO, CaO and so on, can output complex multi-component molten slag after slagging reaction. A small amount of sulfide in agglomerate can form matte in the smelting process. 

    Blast furnace’s specification is 2.6㎡,supply air by Roots blower, feed on either side, auxiliary materials such as agglomerate measured and coke is added into furnace by car with hopper, then output crude lead ingot. Water quenching slag for sale, fuel gas cooling, dedusting and discharge, the soot output return blending system.