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毕业论文 大掺量粉煤灰水泥研制及粉煤灰水化动力学研究，共72页，36097字。
摘 要
粉煤灰的处置和水泥工业能源消耗一直以来都是环境保护和可持续发展的重要问题。粉煤灰的主要化学成分为SiO2和Al2O3，能与水泥水化产生的Ca(OH)2发生二次水化反应，具有很好的火山灰活性，能够替代部分水泥或是作为原料直接用于水泥的生产中。但在常温下这种反应过程非常缓慢，使水泥早期强度过低，造成粉煤灰的利用率一直很低。因此，如何提高粉煤灰的活性就成为粉煤灰综合利用的研究热点问题。本文研究了粉煤灰火山灰活性激发的影响因素，并从热力学和动力学的角度对其火山灰反应进行了分析，研究了不同激发剂对其火山灰活性的激发效果，并对其激发机理作了分析。
研究结果表明，粉煤灰本身并不具有胶凝性，常温下养护或提高养护温度时均不会自己凝结。但在碱性环境中有适量富含活性钙质激发剂组分时，溶液中的OH﹣能打破粉煤灰表面的Al-O、Si-O网络，并与液相中的Ca2+反应生成类似于硅酸盐水泥水化产物的凝胶物质而获得很好的强度。并且，升高养护温度能很大程度地提高碱和石膏对粉煤灰的激发作用。但是，反应进行至一定龄期之后，温度的影响将不再明显。
从热力学方面进行分析，粉煤灰具有较高的活性和水化反应能力，在粉煤灰—石灰—水系统中粉煤灰主要活性成分SiO2和Al2O3的水化反应均能自发进行，且SiO2的水化反应要比Al2O3发生的可能性更大。从化学反应动力学方面分析，粉煤灰的水化反应初期阶段符合一级反应动力学模型，且其反应速率常数与反应温度之间的关系符合阿累尼乌斯定律，据此可计算出其表观活化能。
利用禹州火电厂粉煤灰和郑州金龙水泥厂湿法回转窑熟料，辅助少量自制粉煤灰活性复合激发剂生产的大掺量粉煤灰水泥粉煤灰掺量达到50%以上，3天、28天抗压强度分别达到18MPa和50MPa，并且具有凝结硬化快、早期强度高和后期强度发展迅速等优点，且具有良好的抗硫酸盐侵蚀、抗碱集料反应和护筋性能。粉煤灰活性复合激发剂能够和粉煤灰直接发生反应，生成活性物质，然后吸收液相中的Ca2+生成类似普通硅酸盐水泥的水化产物，而且其中的早强成分也能对粉煤灰的早期活性激发效果有所增加，改善浆体的早期强度。
关键词：粉煤灰 火山灰活性 化学反应动力学 激发剂 表观活化能
Abstract
Disposition of fly ash and energy source consumption of cement industry are two important questions in environment protection and sustainable development. The main chemical composition of fly ash are SiO2 and Al2O3. Fly ash which has fine pozzolanic activity can react with hydration product Ca(OH)2 of cement, so it can replace part cement or be used in cement as raw material. The utilization ratio of fly ash is too low now, because the reaction is very slow at normal temperature, it causes lower strength of cement. Therefore, it has become a hot debate in research of fly ash utilization about how to improve its pozzolanic activity. In this paper, the influence factors of fly ash activity excitation are investigated, the thermodynamics and chemical reaction kinetics of the pozzolanic reaction are analyzed. The effect of different activators are studied, and the mechanism of excitation is also analyzed.
The results show that, the pozzolanic activity of fly ash is potential. Fly ash can not coagulate itself at normal or high temperature, but the Si-O and Al-O net on the surface of fly ash will be broken by OH﹣in alkalinity environment when there is some active calcareous component. It can react with Ca2+ in liquid phase, and produce gelatin similar as Portland cement hydration product to obtain fine strength. In addition, on the premise of activator, higher temperature can increase the excitation effects before a certain age.
The thermodynamics analysis results show that, fly ash has fine pozzolanic activity and hydration reaction ability. In Fly ash-Lime-Water system, the hydration reaction of SiO2 and Al2O3 which are the main active composition in fly ash can carry out spontaneously, and the hydration of SiO2 is easier than Al2O3. The chemical reaction kinetics analysis results show that, the hydration reaction of fly ash from thermal power plant accord with single stage reaction kinetics model, the relation between reaction rate constant and temperature accord with Arrhenius rule, and the apparent activation energy is obtained on these grounds.
High-volume fly ash cement, that the amount of fly ash is more than 50%, is produced with fly ash of Xuchang Yuzhou thermal power plant, rotary kiln clinker of Zhengzhou Jinlong cement factory, and some self-made fly ash pozzolanic activity compound activator. The compressive strength of high-volume fly ash cement at 3 days and 28 days respectively achieve 18MPa and 50MPa, and high-volume fly ash cement congeals hardens quickly, had high early strength, later strength developing rapidly, and it also had fine anti-sulfate corroding, anti-AAR reaction and steel protecting performances. The fly ash activity compound activator can react with fly ash directly and produce active material. Then the active material can absorb Ca2+ in liquid phase and produce hydration products similar as ordinary Portland cement. Besides, the accelerators in the compound activator can increase the excitation effect of early activity, improve early strength of paste.
Keywords: fly ash, pozzolanic activity, chemical reaction kinetic, activator,
apparent activation energy

目 录
摘 要 1
Abstract 2
目 录 I
引 言 1
1 文献综述 3
1.1 前言 3
1.2 粉煤灰的产生和组成 3
1.2.1 粉煤灰的产生过程 3
1.2.2 粉煤灰的组成及性质 4
1.3 粉煤灰的综合利用研究进展 5
1.3.1 粉煤灰在建筑领域的应用 5
1.3.2 粉煤灰在化工领域的应用 8
1.3.3 粉煤灰在农业领域的应用 9
1.3.4 粉煤灰在污水处理中的应用 9
1.4 粉煤灰水泥工业中的应用 10
1.5 粉煤灰水化特性研究进展 11
1.6 粉煤灰活性激发研究进展 12
1.6.1 影响粉煤灰化学活性的主要因素 12
1.6.2 粉煤灰活性激发方法 13
1.7 本课题的技术思路、研究内容和研究方法 19
1.7.1 技术路线 19
1.7.2 本课题的主要研究内容和研究方法 19
2 粉煤灰活性影响因素研究 20
2.1 试验原材料及仪器 20
2.1.1 试验原材料 20
2.1.2 试验仪器设备 20
2.2 试验方法 20
2.3 实验结果与分析 21
2.3.1 不同种类的激发剂与强度发展的关系 21
2.3.2 温度对浆体强度发展的影响 22
2.3.3 反应产物矿物成分及微观形貌分析 23
2.3.3 粉煤灰反应机理分析 26
2.4 小结 27
3 粉煤灰水化反应动力学研究 29
3.1 粉煤灰水化反应热力学判断 29
3.2 粉煤灰-石灰-水体系粉煤灰水化过程 31
3.2.1 粉煤灰水化过程模型的建立 31
3.2.2 粉煤灰水化过程扫描电镜和能谱分析 32
3.3 粉煤灰火山灰反应动力学分析 35
3.3.1 试验原材料及试验设备 35
3.3.2 试验方法 35
3.3.3 动力学模型建立 36
3.3.4 粉煤灰活性物反应速率方程和表观活化能 39
3.4 小结 41
4 大掺量粉煤灰水泥的研究 43
4.1 原材料与方法 43
4.1.1 试验原材料 43
4.1.2 试验方法 43
4.2 实验仪器设备 44
4.3 不同激发剂对粉煤灰水泥力学性能的影响 44
4.3.1 激发剂配比及水泥配合比 44
4.3.2 试验结果及分析 45
4.4 复合激发剂在大掺量粉煤灰水泥中的应用 46
4.4.1 水泥性能检测 46
4.4.2 矿物成分及微观结构分析 48
4.4.3 激发剂的反应机理分析 50
4.4.4 大掺量粉煤灰水泥耐久性研究 52
4.5 复合激发剂对其它粉煤灰的适用性 55
4.5.1 试验原材料 56
4.5.2 试验结果分析 56
4.6 小结 57
5 结论与展望 58
5.1 结论 58
5.2 展望 59
参考文献 60
致 谢 63
攻读硕士学位期间发表学术论文 64