Experimental Research Of Alkaline Pellets Of Chengchao Iron Mine

The best structure of or mathching, alkalinsty of pellets and the process parametersare reschered, try to optimize various performance indicators of alkaline pellets andproduct high quality of alkaline pellets.The process paramenters of acid pellets test results show that:when addition ratiosof bentonite of1.5%, amount moisture of wetting grinding of6%, time of wettinggrinding at2min, pelletizing time at12min, roasting temperature at1200℃, roastingtime at25min, fine quality pelletscan be produced. The green pellets have a dropstrength of9.2times/0.5m, a compressive strength of21.3N/P, a burst temperature of435℃, the roasted pellets have a compressive strength of2640N/P.The alkaline pellets test results show that, when addition ratios of bentonite of1.5%, amount moisture of wetting grinding of6%, time of wetting grinding at2min,pelletizing time at12min,roasting temperature at1250℃, roasting time at30min:(1)when addition ratios of forsterite of3.0%, the alkaline pellets of a green balldrop strength of12.2times/0.5m, a green ball compressive strength of22.9N/P, a bursttemperature of465℃a roasted ball compressive strength of2642N/P could be produced;(2)when addition ratios of dolomite of1.08%, the alkaline pellets of a green balldrop strength of6.4times/0.5m, a green ball compressive strength of18.1N/P, a bursttemperature of420℃, a roasted ball compressive strength of2692N/P could beproduced;(3)when addition ratios of limestone of3.7%, the alkaline pellets of a green balldrop strength of4.9times/0.5m, a green ball compressive strength of15.2N/P, a bursttemperature of465℃, a roasted ball compressive strength of2625N/P could beproduced;(4)when addition ratios of hydrated lime of2.25%, the alkaline pellets of a greenball drop strength of11.9times/0.5m, a green ball compressive strength of23.8N/P, aburst temperature of417℃, a roasted ball compressive strength of2643N/P could beproduced.The TFe grade of acid pellets on the optimal condition is65.84%, the TFe grade offorsterite alkaline pellets, dolomite alkaline pellets, limestone alkaline pellets, hydrated lime alkaline pellets on their optimal condition are65.12%,65.24%,64.42%,65.36%，they can meet the requirement of grade of pellets of the blast furnace, and the chemicalcomposition of several kinds of alkaline pellets are ideal.The reduction degree of acid pellets on the optimal condition is70.61%, thereduction degree of forsterite alkaline pellets, dolomite alkaline pellets, limestonealkaline pellets, hydrated lime alkaline pellets on their optimal condition are83.50%,80.76%,84.58%,85.34%, compared with acid pellets, several basic pellet reductiondegree increased.The XRD analysis results show that, if there is MgO or CaO, the pellets can formcalcium ferrite or magnesium ferrite to reduce the formation of fayalite on roastingconsolidation, it is beneficial to the improvement of the degree of pellets reduction.The date of this research could provide theory support for industrial productionof alkaline pellets, and create economic value.