Improved processing routes for secondary and primary resources used in iron and steel-making

Scenery

Responsible persons : IONKOV Krassimir

Supervisor  : GAYDARDZHIEV Stoyan

Academic partner :

Industrial partner : Arcelor Mittal

Budget : 300 k€

Flowsheet for dephosphorisation of iron ore.

Context

Low phosphorus iron ores are to be depleted within the next two or three decades and the development of technologies rendering high phosporous viable  iron resources  becomes of paramount importance. The cleaning of pig iron from phosphorous  in blast furnaces or convertors is quite inefficient, expensive and energy consuming which necessitates  its removal prior to  metallurgical processing. The physical methods for separation failed because phosphorus forms solid solution with limonite and the main route for problem solving are the pyro- and hydrometallurgy based technologies.

Objectives

The project aims to investigate the dephosphorisation efficiency of limonite oolitic iron ore from Arcelor Mittal’s Lisakovsky deposit, North Kazakhstan. The research targets improvement and optimization of the existing technology at the experimental plant. Roasting at 900°C and acid leach are the basic operations for dephosphorisation of gravity-magnetic iron pre-concentrate and  their upscaling is forthcoming. The process efficiency can be improved by addition of alkaline agents in roasting and by introducing steps aiming  their as well as  the used acids recycling.  In such a way the quality of concentrate and the process economics are improved and the circuit for acids neutralization is facilitated. The latter will make technology more environmentally friendly.

Laboratory equipment

Equipment for size reduction and size distribution determination, magnetic and electric separators, equipment for determination of floatability, leaching vessels and pressure leaching equipment ,  furnaces for roasting – batch and continuous mode.