水泥质量的优劣直接影响到建筑工程的安全,使用品质合格的水泥材料是保证工程结构质量的必要前提,因此快速检测水泥生料成份对于及时指导调整原料配比和保障水泥产品品质具有重要意义。传统的生料检测需要经过取样、制样、化验等环节,检测结果严重滞后于生产。我们通过产学研协同攻关,研制了一套基于激光诱导击穿光谱(laser-induced breakdown spectroscopy,LIBS)技术的水泥生料品质在线检测设备,该设备由LIBS光学检测系统和气动取送样系统两部分组成,实现了对水泥生产线上水泥生料品质的实时连续测量,避免了传统的取制样环节,从而大大缩短了化验时间,所测水泥生料成分的实时数据能够及时指导调整水泥原料的配比,保证水泥质量的合格。我们利用该LIBS水泥品质在线检测设备对水泥生产线上生料中的主成分Al_2O_3,CaO,Fe_2O_3,MgO和SiO2进行了定量分析,利用全谱归一化和支持向量机(support vector machine,SVM)对水泥生料建立定标模型,对水泥生料中Al_2O_3,CaO,Fe_2O_3,MgO和SiO_2测量的最大误差分别是0.34%,0.35%,0.07%,0.14%和0.55%。现场实验结果表明,本水泥生料品质激光在线检测设备的测量结果与传统化验法的结果相吻合,测量精度与X射线荧光光谱法(XRF)相接近,从而证实了LIBS可以作为水泥在线检测的一种有前景的方法。
In engineering construction,cement quality directly affects the safety of construction projects.So it is necessary that we use qualified cement in the engineering structure.It is of great signification that a method detects cement raw material rapidly to adjust the mixture ratio of raw ores to ensure the cement quality.Traditional detection method needs sampling,sample preparation and test,etc.With many procedures,the test results are seriously lagged behind the production process.This paper introduces a set of online analysis equipment to determinate elemental composition of cement powder timely based on laser induced breakdown spectroscopy.This equipment is composed of a LIBS detection system and a pneumatic system.The equipment can achieve the real-time measurement for it needn't sample preparation.Thus,it can guide cement raw material proportioning in time.In this paper,we have quantitatively analyzed the main components of Al_2O_3,CaO,Fe_2O_3,MgO and SiO_2 in the cement raw materials using the full spectrum normalization method as well as the support vector machine.The corresponding maximum absolute errors were 0.34%,0.35%,0.07%,0.14%,and 0.55%,respectively.Results showed that the measurement results of the newly developed LIBS equipment are in accord with those of the conventional chemical method.Furthermore,the measurement precision is in line with X-Ray fluorescence spectrometry.It is confirmed that the LIBS technique could be a prospect method for determination of elemental composition in the cement production industries.