Investigation on Production and Markets of Silica Bricks in China

The annual output of China ' s silica brick amounts up to over 300 thousand tons, which accounts for more than 10% of the total output of silica bricks in the world. Besides satisfying domestic markets , China s silica bricks have been exported to many countries and regions such as Japan, USA etc. In this paper, the situation of silica bricks production, technology, sales and exporting have been described. Also suggestions on improvement of silica bricks quality and exporting, corporation with foreign partners have been put forward in order to win larger market share both at home and abroad.

Chinese Standard on Refractories——Silica Brick for Coke Oven

This standard specifies the classification,specification, test method, quality appraisal procedure,labeling, packing, transportation, storage and quality certification of silica brick for coke oven.

Microstructure Analysis of Used Silica Brick in Coke Oven of Meisteel

Microstructure analysis shows quartz remains more or less in used silica brick for coking chamber of coke oven, and quartz gradually becomes metastable cristobalite and then translates into tridymite in used brick for high temperature combustion chamber. Phase change of silica brick only limits to transformation of quartz and metastahie cristobalite. When finished, structure of silica brick tends to stable. Carbon sedimentates and graphitize. helping to protect the silica brick and improve heat conductivity of silica brick for coking chamber.

RUL of Un-burnt High Purity Silica Bricks Used in Glass Industry

High purity silica bricks have stable physical properties,except for the RUL （0.2 MPa） exhibiting extreme two different levels of high-level RUL T0.6 of 1 683-1 686 ℃ and low-level RUL T0.6 of1 174-1 184 ℃.The low RUL phenomenon was researched,the formation reasons and solutions were analyzed in this paper.The low-level RUL T0.6 of 1 174-1 184 ℃ of the un-burnt high purity silica bricks is a pseudo RUL T0.6 phenomenon for the transformation of crystalline morphology.The real RUL T0.6 of the specimen hot treated at 1 093 ℃ is ＞ 1 680 ℃.Therefore,the un-burnt high purity silica bricks shall be hot treated at about 1 100 ℃ firstly before testing RUL.For the heating up of the lining of glass tank arch,baking curves with long holding time at 1 100 ℃ shall be strictly obeyed to avoid the obvious shrinkage negatively influencing the lining stability.

Development and Application of Zero Expansion Silica Brick for Hot Repairing of Coke Oven

In order to meet the needs of hot repairing technology of coke oven, the zero expansion, silica brick with super properties has been developed, and the problem of poor thermal stability of common silica brick has been over-comed . This product can be directly used after being rapidly heated after construction. At present, it has been applied in coke ovens in Italy and Baosteel.

Silica Refractory Bricks

1 Scope This standard specifies the classification, technical requirements, test methods, quality appraisal procedures, packing, marking, transportation, storage, and quality certificate of silica refractory bricks.

Performance of High Thermal Conductivity Dense Silica Bricks and Their High Thermal Conductivity Mechanism

High thermal conductivity dense silica bricks have the higher thermal conductivity than ordinary silica bricks,which is conducive to the realization of energy saving and emission reduction in the iron and steel industry.The performance of ordinary silica bricks and high thermal conductivity dense silica bricks was compared,and the high thermal conductivity mechanism was analyzed.The results show that(1)compared with ordinary silica bricks,high thermal conductivity dense silica bricks have the characteristics of higher thermal conductivity,lower apparent porosity,higher tridymite content,higher compressive strength,and higher thermal expansion;(2)by increasing the tridymite content and reducing the porosity,the close packing of honeycombα-tridymite improves the density and continuity of the SiO_(2)frame structure of the silica bricks,and the larger area perpendicular to the heat transfer direction improves the thermal conductivity of the bricks;(3)the densification of the silica bricks also increases the thermal expansion of the bricks,but they still meet the standard requirements.

Silica Bricks GB/T 2608-2012

1 Scope This standard specifies the classifcation, technical requirements, test methods, quality appraisal procedure, packing, marking, transportation, storage and quality certificate of silica bricks.

Silica Brick for Hot Blast Stove

This standard specifies the glossary and definition, marking, shape and dimension, technical requirements, test method, quality appraisal procedure, packing, label, transportation, storage and quality certification of silica brick for hot blast stove.

Silica Refractory Bricks for Glass Melting Furnace

1 Scope This standard specifies the classification, technical requirements, test method, inspection rules, marking, packing, transportation, storage and quality certification of silica refractory bricks for glass melting furRaces.

High Quality Silica Bricks for Glass Melting Furnace

This standard specifies the classification, technical requirements, test method, inspection rules, marking, packing, transportation, storage and quality certification of high quality silica bricks for glass melting furnace.

Effects of Spherical Light-weight Aggregates Additions on Workability and Mechanical Properties of Al_2O_3-SiO_2 System Castables

In order to clarify the effect of spherical light-weight aggregates addition on properties of A12 07 - Si02 system castables, adopting ATO mullite traditional light-weight aggregates and ATO mullite spherical light-weight aggre- gates, bauxite homogenization powder, microsilica , cal- cium aluminate cement as main raw materials, light- weight Al2 03 - SiO2 system castables were prepared by replacing conventional light-weight aggregate with spherical light-weight aggregates. The effects of spheri- cal light-weight aggregates addition on workability, me- chanical properties of castables after heated at different temperatures were researched; the microstructure of the aggregates was analyzed by SEM. The result shows that the introduction of spherical light-weight aggregates can significantly improve the flowability and reduce the water addition of the castables. Water demand of the castable is reduced from 18% with the conventional light-weight aggregates to 14% with spherical light-weight aggre- gates. In addition, light-weight castables prepared by spherical aggregates can keep the same workability with- in a wider range of water addition. Therefore, spherical aggregates are user-friendly. The introduction of spheri- cal light-weight aggregates is favorable to packing densi- ty and mechanical properties of castables, such as cold crushing strength, cold modulus of rupture, hot modulus of rupture at 1 200℃.

高炉热风炉不同部位定形耐材选用探讨

高炉热风炉可以根据温度高低分为几个温度区间,分析各区间部位的工况条件,选用合适的耐材至关重要。简要分析了热风炉耐火材料使用范围及使用工况,重点分析了各温度区间,硅砖、高铝砖和黏土砖等几种定形耐火材料的选用。认为:根据工况条件,在合适的地方使用合适的耐火材料是基本原则,“高标低配”或“低标高配”的做法均是错误的;在应用耐材的同时应加强对耐材基础性能的研究,有助于从源头上了解耐材的使用规则,从而达到既节省投资又满足使用寿命的目的。

炉衬材料和加热速率对铸造焦成块性能的影响

以煤粉、焦粉和煤沥青为原料,加水10%(w),捣固为500 mm×350 mm×400 mm的煤饼。入炉温度为650℃时,将煤饼放入单面加热炉内,炼焦终温为1050℃,在不同的加热速率下焦化为焦炭。研究了炉衬材料(黏土砖和硅砖)和加热速率(0.5、0.6、0.7℃·h^(-1))对煤饼自身升温速率和焦化后焦炭性能的影响。结果表明:由于硅砖的热导率优于黏土砖的,硅砖炉衬侧煤饼在水分挥发阶段时间较短,并在200~600℃煤饼第一收缩峰阶段自身升温速率较大,导致煤饼内部应力较大,焦炭块度较低。焦炉炭化室采用硅砖炉墙时加热速率宜在0.5℃·h^(-1),黏土砖作为炉墙时加热速率宜在0.6℃·h^(-1)。

全氧燃烧玻璃窑用耐火材料抗碱蒸气侵蚀性研究

采用坩埚法对全氧燃烧玻璃窑用优质硅砖、零膨胀硅砖、熔铸锆刚玉砖(AZS33)、α-β刚玉砖于1600℃保温24 h进行了抗碱蒸气侵蚀性对比试验,并对侵蚀后试样进行了显微结构分析。结果表明:1)优质硅砖和零膨胀硅砖显气孔率较高,在高温碱蒸气条件下,硅砖中的钙硅氧化物和玻璃相不断析出滴落,持续溶解SiO_(2)颗粒,抗碱蒸气侵蚀性差;2)熔铸锆刚玉砖在碱蒸气的作用下,产生较多的玻璃相,玻璃相滴落后留下气孔,但熔铸锆刚玉砖显气孔率低,碱蒸气侵蚀渗透慢,抗碱蒸气侵蚀性优良;3)α-β刚玉砖的玻璃相含量低,显气孔率低,碱蒸气侵蚀后骨架结构保持完整,抗碱蒸气侵蚀性更优;4)4种砖抗碱蒸气侵蚀性能的优劣顺序为:α-β刚玉砖>熔铸锆刚玉砖>零膨胀硅砖>优质硅砖。

焦炉炭化室用后硅砖的分析研究

为了解焦炉炭化室硅砖在使用中的损毁机制,对使用了40多年的JN43型侧喷式焦炉炭化室的硅砖进行取样分析,对样品的外观、理化性能、物相组成、显微结构等进行了分析研究。分析发现:1)用后的焦炉炭化室上、中、下3个不同部位的硅砖从炭化室到燃烧室方向,都形成了颜色、质地显著不同的层带;2)煤中的焦油组分对炉墙砖产生了很强的渗透作用,而煤中氧化物组分对炉墙砖的渗透轻微;3)炉墙在高温作用下发生烧结,体积总体呈收缩趋势;4)炉墙燃烧室侧约1/3炉墙厚度内的砖中方石英和石英相消失,鳞石英晶粒显著长大,较多开口气孔变成了闭气孔,线膨胀率降低;5)炉墙靠炭化室侧约1/2炉墙内石英和方石英部分鳞石英化,造成该区域线膨胀率降低。

罐式煅烧炉产能因素分析及应用

针对罐式煅烧炉生产运行中出现的首二层温度提升难、频繁“放炮”、料罐硅砖使用寿命短、达不到设计产能等问题,采取了预热空气通道优化、含尘废气收集、石油焦精准配料等一系列改造措施,并规范了罐式炉日常操作方式,使首二层温度提升50℃以上,“放炮”现象基本消除,单罐产能突破设计值100 kg/h。

焦炉用耐火材料的改进及应用

简述了焦炉结构,分析了焦炉所用传统耐火材料存在的不足,介绍了一些新型耐火材料的性能特点及其在焦炉蓄热室、烟道、燃烧室、炭化室、加煤孔、上升管、炉门、热回收焦炉布风器等部位的应用,并对比分析了使用效果。生产实践结果表明:新型耐火材料的应用,对焦炉的节能、环保、使用寿命都具有积极影响,有助于焦化企业的环保升级、降本增效。

硅溶胶-酚醛树脂共结合Al_(2)O_(3)-SiC-C砖性能研究

为了缓解酚醛树脂碳化引起的Al_(2)O_(3)-SiC-C砖组织结构劣化,提升Al_(2)O_(3)-SiC-C砖的力学性能和抗渣性能,以粒度分别为5~3、3~1和≤1 mm的高铝矾土为骨料,以电熔白刚玉(≤0.045 mm)、SiC(≤0.075 mm)、α-Al_(2)O_(3)微粉和鳞片石墨(≤0.15 mm)等为基质,以热固性酚醛树脂和硅溶胶为结合剂,制备了硅溶胶-酚醛树脂共结合Al_(2)O_(3)-SiC-C砖。在酚醛树脂外加量为4.5%(w)的基础上,探究了硅溶胶的加入量(外加质量分数分别为0、0.45%、0.90%和1.35%)对Al_(2)O_(3)-SiC-C砖常温力学性能、高温力学性能和抗渣性能的影响。结果表明:引入适量硅溶胶可以有效提升Al_(2)O_(3)-SiC-C砖的力学性能及抗渣性能,当硅溶胶加入量为0.45%(w)时,试样具有优异的常温、高温力学性能及抗渣性能。

硅砖中α-方石英的晶体结构与形貌

利用光学显微镜、扫描电镜和X射线衍射仪研究了几种不同状态硅砖的晶体形貌和晶格常数。结果表明:经1350℃煅烧72h,1450℃再煅烧3h的块状结晶石英岩,70%的石英已转化为微晶方石英。1430～1450℃经48～72h烧成未用的硅砖主相为鱗石英和方石英,并有少量残留石英。经<1250℃使用15年的硅砖主相为鱗石英和方石英,已不见残存石英。经1550～1600℃使用3年的硅砖的稳定相只有α方石英,其晶格常数为:a0=0.49695nm;c0=0.69250nm,形成的方石英都具有标准的晶格构造,粒状酷似八面体的四方双锥,未见正三角形晶粒。