Recleaning process for section of strong magnetic tailings in mixed lean iron ores

The invention discloses a recleaning process for a section of strong magnetic tailings in mixed lean iron ores, comprising the following steps of: tailing regrinding: adding water into a section of tailings subjected to strong magnetic separation, grinding the tailings into regrinding ore pulp with mineral aggregate proportion of 60-95% and fineness of -0.045mm, and controlling the concentration of the ore pulp at 65-75%; strong magnetic separation: adding water into the regrinding ore pulp and desliming in an ore separation box to obtain bottom ores with the ore pulp concentration of 25-35% and overflow tailings, and feeding the bottom ores into a strong magnetic separator with the magnetic field strength of 5000-20000 oersteds to obtain strong magnetic concentrates and magnetic separation tailings; spiral chute separation: screening the magnetic separation tailings through a spiral chute to obtain spiral chute concentrates with the concentration of 15-25% and spiral chute tailings; and table separation: separating the spiral chute concentrates by a table with the stroke of 8-10mm and the stroke times of 250-300 times/min to obtain table concentrates and table tailings. A regrinding, magnetic separation and recleaning process is adopted for respectively recovering large-grain and fine-grain recovering magnetic iron ores and weakly magnetic iron ores in the section of strong magnetic tailings, and therefore, the recovery rate and the concentrate grade are high. The process provided by the invention is simple and convenient, high in production efficiency, low in production cost, high in concentrate grade and recovery rate and low in tailing grade lower than 10%.