Carbothermic reduction of electric arc furnace dust and calcination of waelz oxide by semi-pilot scale rotary furnace

Journal of Mining and Metallurgy. Section B: Metallurgy

关键词: zinc;    zinc oxide;    iron oxide;    waste mixed oxides;    pyrometallurgy;   

DOI  :  10.2298/JMMB111219031M

来源: DOAJ

【 摘 要 】

The paper gives a common outline about the known recycling techniques fromelectric arc furnace dusts and describes an investigation of apyrometallurgical process for the recovery of zinc and iron from electric arcfurnace dusts (EAFD). In the waelz process, the reduction of zinc and ironfrom the waste oxides using solid carbon (lignite coal) was studied. In thereduction experiments; temperature, time and charge type (powder and pellet)were investigated in detail. It was demonstrated that zinc and iron recovery(%) increases with increasing temperature as well as time. Pelletizing wasfound to be a better method than using the powder as received for the zincrecovery and iron conversion (). In the calcination (roasting) process, crudezinc oxide, which evaporated from non-ferric metals were collected ascondensed product (crude waelz oxide), was heated in air atmosphere. Lead,cadmium as well as chlorine and other impurities were successfully removedfrom crude waelz oxide by this method. In the calcination experiments;temperature and time are investigated in detail. It was demonstrated thatzinc purification (%) increases with increasing temperature. The highest zincrefining (%) was obtained at 1200°C for 120 minutes. A kinetic study was alsoundertaken to determine the activation energy of the process. Activationenergies were 242.77 kJ/mol for the zinc recovery with powder forms, 261.99kJ/mol for the zinc recovery with pellet forms respectively. It was foundthat, initially, the reaction was chemically controlled.

【 授权许可】

Unknown