Advantages of Dry Type Preselection Technology

The rapid development of China's iron and steel industry makes the iron ore demand also grow, so a lot of lean ores whose grade lower than the average level are mined and used, which leading to the increase of processing cost. Dry type preselection technology can save energy and reduce the processing cost.

Dry-preselection operation is normally taken in the mines, and its purpose is to throw the tailings and improve the ore grade. Dry-preselection technology has five advantages:
①Reduce transportation costs of the ore;
②Improve the grade of crude, reduce wet-selection costs;
③Beneficiation medium is air without greater requirement of working conditions; it is much better used in water-scarce areas;
④Tailings are directly discharged into the mine, and do not need to build a tailings pond. In addition, the tailings after simple treatment can be used for farmland afforestation without environmental pollution;
⑤Most of the soil and mud are jettisoned with tailings in dry election, more favorable to subsequent sorting.
In the beneficiation flow, dry-type preselection can be divided into pre-crushing pre-selection and pre-milling preselection.
Pre-crushing pre-selection refers to the selection before secondary crushing and three-stage crushing. It throws away non-magnetic minerals and barren rock that produced in the last crushing process, greatly reducing consumption and pressure of the following crushing.
Pre-milling preselection refers to the selection between fine crushing process and grinding process. After crushing, magnetite material and gangue are further separated, dry separation then can vastly improve concentrate grade so that improve ore taste and reduce grinding quantity.
The dry type preselection has significantly obvious effect; it can greatly improve resource utilization, reduce processing cost, and has been popularized by crushing machine production enterprises.