Iron Ore Concentrate Dressing Down Phosphorus Process Optimization Study

With modern industry's developing rapidly, rich ore and good beneficiability ore in the word are reducing. It is important to research concentration flowsheet for fine iron ore with harmful elementary (phosphorus and sulphur). There are large quantity high phosphorus iron ore in the world. In our country there are 7.45 billion ton high phosphorus iron ore, about 14.86 percent of total iron resource. Meishan iron mine lies in the south-west of Nanjing about 260 million ton. The average phosphorus content of ore body is 0.329%. Partial ore reaches 1%. The type of deposit is Ning-Wu skarn iron ore. With the help of domestic university and institute, Meishan iron mine has studied several dephosphorization flowsheet. But it is still difficult problem for dephosphorization of concentrate and improvement of concentrate recovery. The aim of this paper is to find a proper dephosphorization flowsheet fitted for Meishan iron ore through flowsheet optimization to improve metal recovery and reduce phosphorus content of concentrate and production cost.Using processing low-intensity magnetic separation tailings as sample made high intensity magnetic -anti-floatation dephosphorization flowsheet experiment. Trying to improve iron recovery by improving magnetic field strength. Then use antifloatation dephosphorization technological flowsheet for high magnetic scavenging concentrate. At the same time we studied the influence of magnetic field strength, the amount of wash water and feeding concentration on high intensity magnetic separation and the influence of the amount of collector and sodium silicate on anti-floatation separation. We studied collector MZ's collecting power and selectivity as compared with collector H907.We also have made processing imitation flowsheet experiment, classification- high intensity magnetic separation (coarse)- anti-floatation (fine) separation dephosphorization flowsheet experiment, high magnetic scavenging concentrate-grinding- anti-floatation dephosphorization flowsheet experiment. By comparison we try to find best dephosphorization flowsheet for Meishan iron ore.We disclosed the principle of dephosphorization separation by the influence of mineral magnetic property on magnetic separation, apatite siderite and hematite's property chemical in aqueous medium including mineral's interface characteristic in aqueous medium, the influence of sodium silicate on mineral's interface electric property, fatty acids collector adsorption on the surface of mineral including apatite and siderite, he influence of sodium silicate on collector adsorption, infrared spectrometry test collector MZ adsorption.The results of this paper indicated that high intensity magnetic roughing- high intensity magnetic scavenging- classification- anti-floatation dephosphorization flowsheet fits for Meishan iron ore. It can reduce phosphorus content of concentrate and concentration ratio and tailings grade, improve metal recovery, create good condition for tailings comprehensive utilization. It also indicated that new collector MZ is a kind of high collecting power and good selective reagent.