磷尾矿在生料配料中的应用研究

Research on the Application of Phosphorus Tailings in Cement Raw Meal

磷尾矿是磷矿石选矿后产生的尾矿,主要矿物为白云石,其氧化钙含量在40%左右,同时具有高镁特性,对其在生料配料应用具有一定限制。分析磷尾矿对煅烧熟料的各项经济及性能指标的影响,发现磷尾矿对改善生料易烧性作用不明显,熟料标煤耗变化不大,引入磷尾矿配料后导致熟料MgO和SO_(3)含量增加,熟料中C_(3)S(A矿)和C_(4)AF含量明显增加,而C_(2)S(B矿)和C_(3)A含量明显下降,进而导致熟料3 d抗压强度有上升趋势,而28 d抗压强度下降,熟料的标准稠度用水量下降0.2%~0.3%,凝结时间延长20 min左右。因此,需根据实际需求,考虑是否要重新修正配料方案,以调整熟料矿物组成及其性能。

Phosphorous tailings are the tailings produced after phosphate ore beneficiation,with dolomite as the main mineral composite.The calcium oxide content of phosphorous tailings is around 40%,and they also have high magnesium content,which imposes certain limitations on their application in raw meal batching.By analyzing the impact of phosphorous tailings on various economic and performance indicators of clinker,it was found that phosphorous tailings have no obvious effect on improving the burnability of raw meal,and the standard coal consumption of clinker does not change significantly.The introduction of phosphorous tailings in the raw meal batching leads to an increase in MgO and SO,content in the clinker.The content of C,S(Alite)and CAF in the clinker increases significantly,while the content of C,S(Belite)and C,A decreases significantly,resulting in an upward trend in the 3-day compressive strength of the clinker,while the 28-day compressive strength decreases.The standard consistency water requirement of the clinker decreases by 0.2%~0.3%,and the setting time is extended by about 20 minutes.Therefore,it is necessary to consider whether to re-adjust the batching scheme according to actual needs to adjust the mineral composition and properties of the clinker.