硅酸盐水泥熟料还原料紫外吸收特性的研究

发布时间：2018-05-13 10:07

  本文选题：还原料 + 还原度　； 参考：《广西大学》2013年硕士论文

【摘要】：本课题主要针对水泥生产企业常出现的还原料进行探讨研究,主要研究还原料与正常氧化料之间的差异性,并提出用以表征水泥熟料还原程度的还原度H。利用过渡金属离子-配位体结构在光的激发下,发生电子跃迁而产生紫外吸收特性的原理来分析水泥熟料中的铁相盐时发现：由于三价铁盐具备紫外吸收特性而使熟料在入=1437nm处产生吸收峰,由于还原气氛的存在,使得熟料体系Fe3+降低,从而使得还原料的紫外吸收度低于氧化料,这也就是氧化还原料在紫外光谱中的主要差异性。 通过化学分析纯合成熟料矿物(硅酸盐、铝酸盐和铁酸盐),测定其紫外吸收光谱发现：这三者之间只有铁酸盐具备紫外吸收特性而产生吸收峰,这就表明水泥熟料引起紫外吸收主要是由于铁相盐引起。同时,不同冷却制度的铁相盐都能产生紫外吸收,且两者之间的吸收相差不大。 在水泥熟料体系中,熟料紫外吸收度随体系Fe3+含量递增而增加,两者符合幂函数关系,相关系数达0.96。同时,具备类似铁相盐结构的Mn4+也能引起紫外吸收特性,使得水泥熟料产生吸收峰,从而表明具备“变价金属-配位体“结构是水泥熟料产生紫外吸收的主要原因。 通过对还原料进行不同温度的氧化处理时发现：在相同时间下,熟料紫外吸收度随氧化温度的提高而增加,但在1200-1300℃区间内,紫外吸收度几乎无变化,而且在1300℃下延长煅烧时间至60min也并不能增加熟料吸收度。同时,在对1200℃和1300℃下煅烧不同时间研究中,1300℃下煅烧5min熟料紫外吸收度已无明显增加,而1200℃下煅烧11min熟料紫外吸收度依然增加。 利用紫外光谱对水泥熟料中的铁相盐进行定量分析表明,熟料铁相盐含量正比于紫外吸收度,二者相关吸收R2=0.970,这为我们利用紫外吸收光谱对水泥熟料中的铁相盐进行研究提供了直接的依据。通过对熟料铁相盐紫外吸收特性的研究及还原料的氧化处理后,我们提出还原料还原度的评价标准及定义。标准：将经过1300℃下煅烧30min的还原料粉磨至全部通过80μm方孔筛,称取试样1.0g,在20MPa下压制成型,测定熟料紫外吸收度。定义熟料还原度H等于还原料氧化前后的吸收度差值AA除以氧化后熟料的吸收度。
[Abstract]:This paper mainly focuses on the research of returning raw materials which often appear in cement manufacturing enterprises, mainly studies the difference between returning raw materials and normal oxidizing materials, and puts forward the reduction degree of cement clinker which is used to characterize the degree of reduction of cement clinker. Using the transition metal ion-ligand structure under the excitation of light, When analyzing iron phase salt in cement clinker, it is found that due to the ultraviolet absorption characteristic of trivalent iron salt, the absorption peak of clinker is produced at 1437 nm due to the existence of reducing atmosphere. The Fe3 of the clinker system is reduced, and the UV absorption of the raw material is lower than that of the oxidized material, which is the main difference of the redox material in the UV spectrum. The UV absorption spectra of pure synthetic clinker minerals (silicate, aluminate and ferrate) were determined by chemical analysis. This indicates that the ultraviolet absorption of cement clinker is mainly caused by iron phase salt. At the same time, the iron phase salts of different cooling systems can produce ultraviolet absorption, and the absorption between them is not different. In cement clinker system, the UV absorption of clinker increases with the increase of Fe3 content, and the correlation coefficient is 0.96. At the same time, Mn4 with the structure similar to iron phase salt can also cause ultraviolet absorption characteristics, which makes cement clinker have absorption peak, which indicates that the structure of "variable value metal-ligand" is the main reason for ultraviolet absorption of cement clinker. When the raw materials were oxidized at different temperatures, it was found that the UV absorbance of clinker increased with the increase of oxidation temperature at the same time, but the UV absorption of clinker hardly changed in the range of 1200-1300 鈩，

本文编号：1882707