Panzhihua Iron And Steel Blast Furnace Gas Mud Comprehensive Utilization Of Resources

The course of blast furnace pudding can produce a lot of dirt. Through the collecting and bathing can bring blast furnace (BF) gas mud. The granularity is imperceptibility. The water contained in the sludge is great. Iron zinc and carbon are the mostly valuable element in the BF. Iron mineral mostly exist in the hematite and magnetite. Zinc mostly exist in the zinc oxide. Carbon mostly exist in the coke. As the BF is the waste residue of puddling, the amount is great. So the BF not only impropriate the soil, but also bring disbennifit influence to the surroundings. At present, Panzhihua iron & steel co. produce the BF gas mud 100, OOOt every year. The raw mineral of puddling is the magnetite containing vanadium and titanium. The grade of iron is only 53%. The grade of sinter mineral is only 47-48%. So the percentage composition of iron is relatively low, only 29.70%. The grade of zinc is relatively high, reach 9.92%. And the percentage composition of carbon is relatively high, reach 16. 80%. In the next place, the BF gas mud is the production through sinter in high temperature. SiO₂, Al₂O₃ and iron was melted together partly, which increase the difficulty of mineral processing. Contraposing the speciality of the BF gas mud in Panzhihua iron & steel co. Contraposing these questions, we have research on comprehensive utilization of BF gas mud.First, the conventional method was used in the test to reclaim the iron ore in the BF. Which include magnetism separation, gravity concentration, reverse flotation. Through comparing, we selected spiral concentrator to reclaim the iron. Following, we tested the time of gravity concentration, we adopted one roughing, two cleaning and then we scavenge the tailings of the two cleaning. In this way, we can increase the recovery and ensure the grade. Finally, we research to reduce the content of zinc of the iron concentrate through flotation. The result indicated that this method can reduce the content of zinc in effect, and can increase the grade of ironconcentrate and ensure the recovery. Through the united flow of gravity concentration and reverse flotation can gain the result: the grade of iron concentrate is 47. 20%, the recovery is 49. 24%, the content of zinc is only 2. 89%.Second, we have research on reclaiming zinc from the tailings. Through comparing flotation and acid leaching. Acid leaching can reclaim the zinc in effect. In order to utilize the resource comprehensive and protect the environment, we adopted trash acid in Panzhihua iron & steel co. Through the tests on whisk time, acid dosage, the ratio of liquid and solid, we ensure the best condition of leaching: whisk time: 30min;acid dosage: 2.0t/t; the ratio of liquid and solid: 3:1; temperature: normal; whisk rate: over 200r/min. In this condition, the leaching rate of zinc can achieve 98. 75%.As the leaching solution contain Fe²⁺. we have research on the conventional process of the dividing iron. We have research on the dosage of lime and natrium sulphide. But the effect was bad. After the dividing of iron, through controlling the dosage of natrium sulphide, we can got the high grade and recovery of zinc. But the flow is complex, so we cannot adopt.Finally, on the basis of the solubility products of ZnS and FeS. Zn²⁺ will create deposition first. So we choose to swing in with natrium sulphide directly. Through controlling the dosage of sulphide natrium, we can control the deposition of iron. When the dosage of sulphide natrium is 1. 50 times of the requiring, the grade of zinc concentrate can reach to 44. 56%, the recovery is 92. 83%.Finally, we can adopt flotation to reclaim the carbon from the zinc leaching residue.