摘要：焦炉是主要由硅砖、粘土砖、高铝砖等材料搭砌而成，用于炼焦的反应炉。炼焦煤，在隔绝空气的条件下，炉内加热至1000oC左右，是通过热分解和结焦产生焦炭、焦炉煤气和其他炼焦化学产品的工艺过程。本论文，针对宝钢三期焦炉保护板和炉门框缝隙冒烟影响生产和环境的难题，提出开发以硅溶胶为连续相、亚微米和纳米无机物为分散相的高温密封材料的思想，同时便于现场应用，以此来杜绝焦炉炉体结构缝隙冒烟这一生产过程中的环保问题。试验设计选用硅溶胶溶液为连续相，填料选用超细亚微米氧化铝，二氧化硅以及滑石粉，由此试制出七个不同方案的密封剂，样品再经105oC、300oC、500oC、800oC四个温度的高温烧结试验。为科学探索密封剂的作用效果以及高温下特性、组织结构变化，针对不同阶段的样品采用现代分析方法，高倍显微镜、激光粒度仪、X射线粉末衍射仪等对原料粒径、密封剂经过高温烧结后的形貌、物相组成进行了表征。试验优化结果为：高温无机-无机复合材料莰缝密封剂选用的溶液为硅溶胶，填料为氧化铝、颗粒状纳米二氧化硅以及滑石粉。硅溶胶的质量与氧化铝和二氧化硅颗粒质量总和之比为1:3.5最佳，并加入总质量10%的1000目滑石粉，显著地改善填料之间的配伍性以及样品整体的力学强度，从而能降低样品的孔隙率，有利于烧结，提高产品密封性。试验发现，经由800oC烧结后无新物质生成，但不排除经更高温度烧结后是否有新物质产生。

关键词：硅溶胶；二氧化硅；密封剂

Abstract：Coke oven is mainly composed of silica brick, clay brick, high alumina brick and other materials, which is used for coking reaction furnace. Coking coal, under the condition of isolation air, is heated to about 1000oC in the furnace, which is the process of producing coke, coke oven gas and other coking chemical products through thermal decomposition and coking. In this paper, targeting the problem of smoking from the protection plate and furnace door frame gap on Baosteel's third phase coke oven, development of high temperature sealing materials with silica sol as continuous phase, submicron and nanometer inorganic materials as the dispersed phase was proposed, to solve the environmental problems arising from the coke oven production process. Seven sealants were prepared, in which silica sol was selected as continuous phase, alumina, silica and talc powder were used as the filler, then above components were mixed and sintered at 105oC, 300oC, 500oC and 800oC, respectively. To explore the sealing effect and the changes in microstructure and characteristics of sealants under high temperature, high power microscope, laser particle size analyzer and X-ray powder diffractometer were used for analyzing the particle size of raw materials, the morphology and phase change of sealants after high temperature sintering. The results show that the performance of high temperature inorganic-inorganic composite material is best when silica sol is used as the matrix phase, alumina, granular silica and talcum powder are used as the filler, and the mass ratio of silica sol to alumina and granular silica is 1:3.5, and the mass ratio of 1000 mesh talcum power is 10%. This can be attributed to the compatibility between the fillers and the high mechanical strength of the sample, which can reduce the porosity of the samples, be beneficial to the sintering and improve the sealing effect of the products. It was found that no new phase was formed after sintering at 800oC, but the possibility of new phase produced after sintering at higher temperatures could not be ruled out.

Keywords：Silica sol; Silica; Sealant

目录

1.1引言 4

1.2硅溶胶 7

1.2.1硅溶胶概述 7

1.2.2硅溶胶的制备 7

1.2.1离子交换法 8

1.2.2硅溶解法 9

1.2.3电解电渗析法 9