Practical Study On The Optimization Process Of Sintering Production At YiGang Iron＆Steel

With the progress in BF smelting technology and the continuously increasing ofproduction capacity, the sinter capacity of Shanxi Yigang Iron&Steel Company(JISCO) canno longer meet the needs of raw materials for blast furnace with high productivity. In theJISCO sintering process, due to the defects of second mixer device parameters and the limitsthat JISCO has no fixed raw material base area, most iron ores need to be purchased orimported. For a long time, the rate of concentrate is only15-20%and grain size is a littlecoarse, only30%of the concentrate grain size is smaller than200mesh. When the rate of fineore reaches to40%-45%, the grain size composition of sinter mixture is polarization, thecontent of grain size below3mm can reach to32%, and the rate fluctuate greatly with4%-5%.The physical properties and chemical composition of raw materials are variable, which iscurrently a restrictive step that constrained the capacity of sintering machine.In order to make the best use of existing material conditions to improve the sintercapacity of JISCO, experimental studies for optimizing the granulation and sinter materialproportion were studied, the results were as follows:1) rotational angle, speed and feeding amount of drum mixer have a great impact ongranulation efficiency of sinter mixture, under the experimental conditions, the optimisticangle parameter is1.8°, rotational speed is20rpm, feeding amount is20kg each time, belowor above this standard, granulation efficiency has different degrees of variation. Thegranulation efficiency is much better with longer mixing time, the appropriate mixing time is5min, and when the mixing time exceeds6min, the granulation efficiency of sinter mixtureimproves to a lesser extent, tends to be stable.2) Under the existing material conditions of JISCO, with many sintering experiments, wecan discover that when the match of material is Newman powder40%, low grade printingpowder5%, Dai County concentrate25%, Fushan concentrate10%, production output of sinter is increased significantly. When sinter basicity is2.10, sinter has a better drum strength;reducibility and low-temperature reducibility have a significant improvement.3) When taken the measures of optimizing the granulation and sinter material proportion,comparisons between the experimental results and field data of JISCO show that sinter yieldis raised about3%, return sinter decreased, tumbler strength increase significantly, andmetallurgical properties of the sinter are better.