Method for improving iron and reducing phosphorus of high phosphorus oolitic iron ore by magnetic roasting and two-step bioleaching

Abstract

The invention discloses a method for improving iron and reducing phosphorus of high phosphorus oolitic iron ore by magnetic roasting and two-step bioleaching. The high phosphorus oolitic iron ore is subjected to magnetic roasting in a box-type resistance furnace, and ore grinding, magnetic separation and then a microbiological leaching experiment; and the used strain is thiobacillus. Microbes arecultured in a bioreactor for 5 to 30 days so as to obtain bacterial solution with the pH value between 0.5 and 1.5; filer liquor is utilized for ore leaching and phosphorus removal, the concentrationof the ore pulp is 1 to 20 percent, and the leaching time is 0.5 to 24 hours; and the final iron core concentrate product is obtained after solid-liquid separation. The roasted ore is leached by adopting a two-step bioleaching method, the phosphorus content in the iron ore can be reduced to less than 0.20 percent from 0.80-1.25 percent, simultaneously the grade of the final iron ore concentrate is improved to 55-62 percent from 43-45 percent, the sulfur content is less than 0.20 percent, and the iron loss rate is less than 4 percent. The method has good iron improving and phosphorus removing effects, can improve the concentration of ore pulp, shorten ore leaching time and recycle nutrient substances, and is particularly suitable for developing and utilizing high phosphorus oolitic iron ore rich in China.

Description

technical field [0001] The present invention relates to a magnetization roasting-two-step biological leaching method for iron ore reduction and phosphorus reduction of high-phosphorus oolitic iron ore, in particular to a two-step leaching method using Thiobacillus to leach high-phosphorus oolitic iron ore after magnetization roasting Method of Phosphorus in Stone. Background technique [0002] With the development of the metallurgical industry, smelters have higher and higher requirements for the quality of iron concentrates, and the implementation of new metallurgical processes has put forward higher requirements for the quality of iron concentrates. As harmful impurity minerals in iron ore, apatite and collophanite often appear in weakly magnetic iron ore. In my country's Hunan, Hubei, and Yangtze River basins, a large amount of phosphorus-containing iron ore is buried. For example, the phosphorus content of the Meishan iron mine is as high as 0.38%, and the "Ningxiang-st...

AI Technical Summary

Problems solved by technology

[0005] However, in terms of phosphorus removal from high phosphorus oolitic iron ore, there are few successful biological phosphorus reduction methods reported at home and abroad. Mainly focus on the single acidophilic thiobacillus, and mostly focus on microbial culture and ore leaching in the same process, resulting in too long immersion time of iron ore in acidic solution, high iron loss rate, and at the same time, the added energy substances , such as, He Liangju et al. [He Liangju, Hu Fangren, Wei Dezhou. Research on Microbial Dephosphorization of Meishan High Phosphorus Iron Ore, Mining and Metallurgy, 2000(9): 1:31-35] added pyrite, Jiang Tao et al. [CN 101037724A 2007.4 .28] Adding ferrous sulfate or Shen Shaobo [CN 101597037A 2009.7.15] Adding sulfur powder, etc., not being used by microorganisms or after the action produces ferrite precipitation, which is mixed in the final iron concentrate, resulting in iron after phosphorus removal The sulfur content in the ore is too high

Images