关键词: 磁铁矿, 预选抛废, 磁选, 工艺流程设计

Abstract: In order to make efficient use of an iron ore in Qinghai，systematic ore properties，benefi‐ ciation test research and technological process design were carried out. The iron grade of the raw ore is 34.02%，and the iron is mainly present in the magnetic iron，with a share of 86.05%. Through the compari‐ son test of stage grinding-stage magnetic separation (one cleaning)，stage grinding-stage magnetic separa‐ tion (two cleaning)，one-stage grinding-three magnetic separation，pre-selection and tailings discarding comparison of dry & wet，wet tailings discarding-stage grinding-stage magnetic separation，the recom‐ mended separation process is wet tailings discarding-stage grinding - stage magnetic separation. The de‐ signed beneficiation process flow has been improved in combination with the practical experience in recent years. The magnetic pulley pre-selection and tailings discarding operation has been added，and the step�grinding and step-selection process flow has been adopted to discard the gangue that has been dissociated as soon as possible. Auxiliary methods such as demagnetization，magnetic gravity separation and tailings recovery are used to strengthen the separation effect. The designed process of the concentrator reflects the principles of energy saving，high efficiency and maximum utilization of resources，and provides a new idea for the construction of this type of iron ore concentrator.

Key words: magnetite, discarding by pre-concentration, magnetic separation, technological process design