用煤泥作还原剂制备褐铁矿含碳球团

Preparation of carbon-containing pellets made from limonite using coal slime as reducing agent

为确定低品位褐铁矿制备含碳球团的最佳工艺参数,以煤泥为还原剂,湿球落下强度和干球抗压强度为评价指标,探索了煤泥添加量、原矿粒度、水用量、成球压力、膨润土用量对含碳球团强度的影响。结果表明:球团强度因煤泥种类不同而有一定差异,在煤泥B加入量为25%,原矿粒度-0.074 mm含量占76%、水用量为4%、成球压力为10 MPa、膨润土用量为4%条件下,可以获得湿球落下强度7.3次/P,干球抗压强度197.6N/P的冷固结含碳球团。煤泥的高灰分、高黏性有利于提高冷固结球团强度且利用废弃物煤泥作为还原剂再利用,可减少污染,提高经济效益。

In order to work out the optimum parameters of carbon-containing pellets made from low-grade limonite, with the coal slime as the reducing agent,and with the drop strength of wet balls and compressive strength of dry ball as evaluating criteria, effects of dosage of coal slime, particle size of raw ores, water requirement, pellet pressure and bentonite consumption on strength of carbon-containing pellets are explored. The results show that the pellet strength is somewhat different due to different kind of coal slime, cold bonded carbon-containing pellets with drop strength of wet ball as 7. 3 times/P and compressive strength of dry ball as 197.6 N/P can be obtained under the conditions of coal slime B addition 25% ,particle size of -0. 074 mm raw ores accounting for 76% ,water requirement 4% ,pellet pressure 10 MPa and bentonite consumption 4%. High ash content and high viscosity of coal slime are favorable for improving the strength of cold bonded pellets, and the recycling of waste coal slime as reductant can reduce pollution of environment and improve economic efficiency.