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This is how genuine RuZ1 primary zinc is produced

Harbour / Delivery of Materials
At the company's own harbour on the Dortmund-Ems Canal, the zinc concentrates (zinc ores upgraded at the ore mine) are delivered as a fine-grained bulk material from all over the world. Enclosed conveyor belts convey the concentrates into closed ore warehouses.
Waelz oxides, as the second important raw material source, are delivered by silo trucks or in big bags. The harbour is also used for transporting sulphuric acid away.
Stockyard / Concentrate Storage
Here the zinc ore concentrate is stored. A grab crane picks up the different concentrate types, mixes them and drops them on conveyor belts that convey the mixture, referred to as blends, into the roasting works building.
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Roasting Gas Cleaning
In two fluidized bed furnaces, the sulphur from the zinc concentrates is burned at almost 1,000øC with atmospheric oxygen to form sulphur dioxide gas. The roasted product obtained is now mainly acid-soluble. Cooled and ground it is pumped pneumatically into the storage silos of the lixiviating plant.
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Sulphuric Acid Production Plant
The gases from the zinc ore roasting plant are subjected to multi-stage wet cleaning and freed of traces of mercury. The SO2 from the roasting gases free of dust and mist is converted into sulphuric acid in the contact plant. Put into intermediate storage in three large tanks, it is transported to the customers by trucks and ships.
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Leaching and purification
The calcine and Waelz oxide are mixed separately with spend acid to dissolve zinc, copper and cadmium. The components that are difficult to dissolve in diluted acid (e.g. zinc-iron oxides, lead, silicic acid, aluminium oxide and silver) remain as residues. The remaining free sulphuric acid is neutralized with the calcine or Waelz oxide at the end of the leaching process while the solid residues are incinerated.
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Storage and mixing station
The cleaned neutral leach is cooled to electrolyte temperature and mixed with heated recirculated spend acid returning from the bath halls. Part of the spend acid from the electrolytic process is conveyed to the leaching department for use in the leaching of calcine and Waelz oxides. Some of it is also conveyed after de-zincing in the leaching department to the waste-water-treatment plant.
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Electrolysis / Cell house
The thus cleaned electrolyte is transported through channels and distributor pipes to the 106 electrolysis basins, each of which holds 85 anodes and 84 aluminium cathodes. This causes metallic zinc to precipitate on the aluminium cathodes. The precipitated zinc is removed from the aluminium plates by stripper machines cleaned and transported to the casting plant.
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Smelting and casting plants
The cathode zinc produced in the cell house is melted in two induction furnaces. The liquid zinc is then channelled to foundry circles where blocks of one or six tonnes are cast. Zinc-containing scrap and returned metal are used in process again.
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Other facilities / plants
Various other facilities are required for operating the above systems. These include among others a waste-water-treatment plant, a laboratory, a central compressed-air supply, extensive power distribution, central and local workshops, magazines and intermediate storage facilities, social buildings, gates and administration.
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