DECREPITATION BEHAVIOR OF SOUTH AFRICA,PB AND AUSTRALIA LUMP ORE
In recent years,the steel industry has achieved the goal of cost reduction,efficiency improvement,energy conservation,and emission reduction by increasing the proportion of ore used in furnaces.However,the powder generated by thermal cracking of lump ore can easily reduce the permeability of the upper part of the blast furnace,thereby affecting the smooth operation of the blast furnace.The study of the thermal decrepitation performance of lump ore is beneficial for providing experimental basis for the raw material ratio during production.This article takes South African,PB and Australian lump ores as research objects,systematically studying the effects of heating temperature,heating time,and high-temperature pretreatment on the thermal decrepitation performance of lump ores,as well as the ability of lump ores to produce powder again under external stress extrusion friction after thermal cracking.The experimental results show that the degree of thermal decrepitation of lump ore is positively correlated with the content of crystal water and burning loss.The higher the temperature,the more severe the thermal decrepitation situation.The thermal decrepitation index of South African lump ore is less affected by temperature than PB and Australianlump ores,and their resistance to high temperature decrepitation is stronger.As the heating time increases,the thermal decrepitation index increases,with a larger change in the first 10 minutes and a smaller change in the second 20 minutes;High temperature pretreatment reduces the crystal water content of the lump ore,effectively relieving the internal stress of the lump ore and suppressing the occurrence of thermal decrepitation.After preheating at 400 ℃ for 60 minutes,the thermal decrepitation indices of PB and Australian lump ores were 1.52％and 0.86％,respectively,indicating a significant decrease in thermal decrepitation indices.In addition,PB ores and Australian ores have a stronger ability to generate powder again.
lump oredecrepitation indexheating temperatureheating timehigh temperature pretreatment
万方数据
维普
