Experimental Study On The Iron Recovery From A Tailling From Rare-earth Flotation Using Magnetic Separation

Due to the massive consume of mineral resource,the ore is being deficient day by day. The tailings,a kind of main solid waste,not only have taken the large numbers of lands, and polluted the environment,but also resulted in the waste of useful elements in the tailings. How to effectively recycle the useful resources in ore tailings is of great significance for the stable development in national industry and economy.The constituent of Bayunebo taillings from rare-earth metal flotation is relatively simple, and the contents of iron, rare earth and the niobium content is up to 18%, 7-8%, 0.2%. It is very necessary to recycle these elements in order to elevate the utilization efficiency and save production cost. But the general dressing technics isn't very ideal in the grade iron concentrate or the economic cost.In this paper, the recovery of iron from Baiyunebo taillings,which results from rare-earth metal flotation,was investgated experimentally in terms of"the high gradient magnetic separation"and"the microwave magnetization roasting - weak magnetic separation"two experiment schemes are designed as follows.For the first,the experimental study is carried out with the high gradient magnetic separation directly to the tailings,the effect of the magnetic field strength,slurry velocity, slurry density, the tailing size and the magnetic dielectric on the separation efficiency was investigated. When the first separation field is 0.8T and second separation field is 0.3T, the tailings of TFe18.04% were tested with simple high gradient magnetic separation, the iron concentrate obtained is 46.1% in grade and 53.8% in recovery using a slurry flow velocity of 4.2cm/s, a slurry density of 20%, and the tailing size of -200 sieve mesh number,a magnetic dielectric filling rate of 8.6%. The rare earth and the niobium is concentrated in the tailings of magnetic separation,also rare earth,the niobium obtained is 85%~90% in recovery. So it will be very advantageous to recover the rare earth and the niobium in the tailings of the high gradient magnetic separation.For the second,the influence of Carbon content on rising-temperature time and speed and the reduction rate of hematite was researched In the experiment of the microwave magnetization roasting.the tailings from rare-earth metal flotation, which have been deoxidized by the microwave,is researched by the weak magnetic separation. the agglomeration of the deoxidized tailling, Carbon content and excited current of magnetic tube is investigated. Test result shows: the iron concentrate of 64.6% in grade and 43.6% in recovery can be obtained through the weak magnetic separation by magnetic tube,when exciting current is 0.11T and carbon content is 4%.