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1.
目的研究利用工业废料配制高硅贝利特硫铝酸盐水泥及不同温度制度下几种晶型稳定剂对该种水泥强度的影响.方法以单掺和复合掺加的方式将稳定剂配料加入到水泥之中,在不同温度下烧成、磨细、水灰比一定、制成试样、测各龄期强度.结果实验证明单独加入和复合加入稳定剂后,使水泥的后期强度提高,但提高程度有所不同,另外,不同的烧成温度对高硅贝利特硫铝酸盐水泥强度影响也很显著.结论单一稳定剂加入对高硅贝利特硫铝酸盐水泥强度的影响程度由大到小依次为氧化硼、氧化硫、氧化钛;两种稳定剂复合后的效果明显好于单掺效果;1250℃时β—C2S容易生成,有利于后期强度增长,1300℃有利于无水硫铝酸钙生成,早期强度较高.  相似文献   

2.
高硅贝利特-硫铝酸盐水泥的热分析实验研究   总被引:5,自引:0,他引:5  
为了探明在1200℃左右烧制时高硅贝利特硫铝酸盐水泥其强度高于烧成温度更高这一特性的原因,在文献[1,2]XRD的分析基础上,笔者对石膏、铝酸钙、无水硫铝酸钙、硅酸二钙和铁铝酸四钙、高硅贝利特硫铝酸盐水泥进行了热分析,研究表明:当水泥的煅烧温度低于1200℃时,硅酸二钙和无水硫铝酸钙并没有大量生成,石膏的化合率仅为4%,因此强度很低.当温度超过1250℃时,石膏开始分解,石膏、无水硫铝酸钙和高硅贝利特水泥在1375℃的石膏分解率分别为8%、30 5%、26 68%,不利于无水硫铝酸钙的稳定存在,甚至可导致无水硫铝酸钙的分解,最终降低水泥的强度.  相似文献   

3.
高硅贝利特-硫铝酸盐水泥与矿渣复合的实验研究   总被引:7,自引:3,他引:4  
在分析硫铝酸盐水泥应用现状及存在问题的基础上,提出了高硅贝利特-硫铝酸盐水泥与矿渣复合,能够进一步完善硫铝酸盐水泥的性能及扩大硫铝酸盐水泥的应用范围,通过实验证明了二者复合的可能性,并对二者复合机理进行了探讨。  相似文献   

4.
目的研究氧化钛对硅酸二钙(C2S)形成的影响,解决含钛尾矿硫铝酸盐水泥生产的问题.方法利用热分析、粒度分析、f—CaO和XRD分析研究氧化钛对硅酸二钙矿物相形成的影响.结果随着TiO2掺入量增加,TiO2有明显的矿化作用和降低钙硅体系低共熔点的助熔作用,TiO2对β-C2S的稳定有一定的作用;在有SO3的情况下,TiO2对β-G2S的稳定作用更明显.结论氧化钛具有促进C2S生成的矿化作用,同时还有降低钙硅体系低共熔点,生成较多液相的助熔作用;在有SO3的情况下,氧化钛对β-C2S的稳定作用更加明显,为利用含钛尾矿生产低钙水泥提供了科学依据.  相似文献   

5.
以化学试剂配制水泥生料,添加不同品质高硫煤,借助XRD测试手段就高硫煤燃烧对水泥熟料矿物形成过程的影响规律做了初步探讨。结果表明:在较低温度下,高硫煤燃烧能够促进f-CaO和SiO2的吸收,加速固相反应,但超过1 300℃反而会阻碍f-CaO的吸收,且煤中硫含量越高,这种作用越明显;高硫煤燃烧虽在高温段不利于f-CaO吸收,却在一定程度上降低了C3S形成温度;S在高温下主要生成了硫铝酸钙(C4A3-↑S),但其在超过1 300℃会发生分解,且C4A3-↑S的存在阻碍了C3A的形成。  相似文献   

6.
根据贝利特硫铝酸盐水泥的矿物组成及工艺控制要求,设定其熟料矿物由硅酸二钙(C2S)、硫铝酸钙(C4A3S—)和铁铝酸四钙(C4AF)组成,根据推导出的公式计算熟料的化学组成,然后由质量守恒原则列出方程组,求解并计算生料的配料组成。实例验证结果表明,本方法可行。  相似文献   

7.
采用电预热然后用微波加热二次加热方法,快速烧成了Ca4Al6SO16,Ca3SrAl6SO16,Ca3BaAl6SO16等硫铝酸盐矿物。电预热温度1200-1300℃,然后在微波炉中加热1min30s-2min,试样f-CaO值可降至0。3种矿物中Ca4Al6SO16最容易烧成,Ca3SrAl6SO16最难烧成。掺入Fe2O3、Cr2O3、MnO2等外加剂能促进硫铝酸盐矿物的烧成。XRD分析表明,烧成矿物的衍射峰特征与常规烧成的矿物一致。  相似文献   

8.
硅酸盐-硫铝酸盐水泥混合体系的试验研究   总被引:12,自引:0,他引:12       下载免费PDF全文
研究了不同比例的硅酸盐、硫铝酸盐水泥混合体系的凝结时间、水泥砂浆的强度性能,并对一定混合比例的OPC-SAC水泥进行了XRD、SEM和水化量热测试。结果表明,硅酸盐水泥与硫铝酸盐水泥混合,SAC中的C4A3-S矿物与OPC中的C3S矿物在共同水化过程中有相互促进的作用,会使混合水泥水化和凝结加速;混合水泥的强度性能与两种水泥的混合比例有关。本研究可对硅酸盐-硫铝酸盐水泥混合体系的应用提供借鉴。  相似文献   

9.
石膏掺量对高贝利特-硫铝酸盐水泥性能的影响   总被引:2,自引:0,他引:2  
利用循环流化床(CFBC)固硫灰代替部分铝矾土、石膏等原料制备高贝利特-硫铝酸盐水泥,并采用XRD、SEM等方法研究了石膏掺量对该水泥凝结时间、抗压强度、水化产物和微观结构的影响。结果表明,利用固硫灰等原料制备的水泥熟料的矿物组成主要有C2S、C4A3S、铁相等;掺入石膏会缩短水泥的凝结时间,最佳石膏掺量为9%;水泥3d、28d净浆强度可以达到39.00MPa和82.59MPa;掺入适量石膏能促进C4A3S和C2S水化,掺量不足会使AFt向AFm转化,掺量过大反而会阻碍C4A3S的水化,进而影响水泥强度;不同石膏掺量下的水泥水化产物主要为AFt、AFm、C-S-H凝胶和铝胶等。  相似文献   

10.
胶凝材料组成对混凝土TSA硫酸盐侵蚀的影响   总被引:2,自引:0,他引:2  
研究不同水泥品种、矿物掺合料对混凝土抗TSA侵蚀性能的影响规律,采用掺30%石灰石粉填料的胶砂件,测试各砂浆在5±1℃的2%MgSO4溶液中浸泡1年后的外观破损与强度损失情况,通过X-射线衍射仪分析各砂浆的矿物成分.结果表明:不同品种水泥的抗TSA侵蚀能力由高到低依次为:硫铝酸盐水泥 硅酸盐水泥复合>硫铝酸盐水泥>抗硫酸盐水泥>普硅水泥.掺硅灰和矿渣细粉均能明显改善混凝土抗TSA侵蚀性能,且矿渣粉掺量越大效果越明显.由于粉煤灰活性低,掺量较少时可在一定程度上减缓TSA侵蚀过程,但掺量过多时反而产生不利影响.  相似文献   

11.
研究了铝酸钙水泥、铝酸钙水泥/SiO2微粉、α—Al2O3微粉以及α—Al2O3微粉/SiO2微粉4种结合剂对Al2O3一SiC-C质浇注料性能的影响。结果表明,加入α—Al2O3微粉结合剂的材料性能最好,可以获得性能良好的铁沟浇注料。  相似文献   

12.
To analyze the influence of new compound admixture on shotcrete performance, the ordinary Portland cement pr425 was used as matrix components. The optimum proportion of admixture was obtained by analyzing the influence of content on cement setting time and compressive strength. The microstructure of cement test block and the mechanism of reducing dust of composite macromolecule admixture were analyzed by scanning electron microscopy and infrared spectroscopy. It was shown that the ratio of polyacrylic acid was 0.02%. The ratio of J85 accelerator was 5%. The ratio of bentonite was 4.5% in composite admixture. The most optimal content of admixture in the slurry was 7%. The compound coagulant formed by additive together with C_3 A, C_4 AF which provided nucleation for hydration and crystallization of C_3S and C_3S, and played an active role to promote the activity of the mineral admixture in cement, and increased the elastic modulus of C-S-H gel and accelerated the hydration process of portland cement. Bentonite and polyacrylic acid promote the wettability, cohesiveness and workability of cement paste in the process of hydration. The formation of cement test block gel was even. The interface between the matrix phase and the aggregate phase was not obvious which ensured the matching between the matrix and the aggregate phase. The addition of bentonite formed hydrogen bonds in cement paste and improved the cohesiveness of the system. The J-85 accelerator promoted the combination of aluminate and gypsum which hindered the formation of calcium carbide around the cement particles which made cement rapid condensation. Polyacrylic acid mainly changed the strength of hydroxyl absorption peak in cement paste to improve the initial strength of cement test block. The addition of new admixtures promoted the process of cement hydration to be more thorough and affected the later strength development of concrete by affecting the formation of calcium carbonate stone.  相似文献   

13.
本文研究了硫酸钡在不同煅烧温度下对含碱水泥熟料形成和性能的影响,并对其作用机理进行了探讨。结果表明,BaSO4参与煅烧虽仍能发生碱的硫酸盐化反应,部分BaSO4还与铝相作用生成含钡无水硫铝酸钙,中间相中铝酸盐矿物减少。但系统中钡的影响更为突出,BaO主要固溶于贝利特中,使其以高活性的α型存在,钡同时又表现出强烈阻碍A矿形成的特性。尤其随熟料硫碱摩尔比升高,钡的负作用更显著,熟料中f-CaO剧增,各种性能严重变劣、表明按碱硫酸盐化的观点,不宜采用硫酸钡作为含碱熟料煅烧的改进剂。  相似文献   

14.
Optimization of the content of tricalcium silicate(C 3 S)of high cementing clinker was investigated.The content of free-CaO(f-CaO),mineral composite,the content of C 3 S in the clinker and the hydration product were analyzed by chemical analysis and X-ray diffraction(XRD).K Valuemethod of QXRD was selected as a quantitative analysis way to measure the content of C 3 S,and the strength of cement paste was determined.The results show that at a water cement ratio of 0.29,the strength of cement paste with 73%C ...  相似文献   

15.
在低温水热条件下,以BiCl3、Na2S2O3(或Na2S、硫脲)为反应物,制备了硫化铋(Bi2S3)纳米晶.用X射线粉末衍射(XRD)、扫描电镜(SEM)及纳米粒度测定仪对样品的结构及形貌进行了表征分析.结果表明,所得样品为正交晶系的Bi2S3纳米晶,形貌主要为纳米棒;同时硫源、反应温度及反应时间会影响样品的粒径.  相似文献   

16.
报道了用sol gel方法在玻璃管上制备二氧化钛薄膜对清除乙烯气体的光催化实验,研究了二氧化钛一次镀膜对乙烯浓度随催化反应时间的变化关系。结果发现,二氧化钛镀膜有较好的清除乙烯的效果,当反应进行到46h时乙烯气体的色谱峰完全消失,即乙烯气体已经被完全清除掉,对相同处理条件下的二氧化钛粉体做XRD分析知该条件下的二氧化钛为锐钛矿晶型。  相似文献   

17.
Analytical reagents have been used for preparation of pure C_3S and its solid solutions containing Fe_2O_3 or FeO. The data from M(?)ssbauer Spectra of samples suggest that 4Si~(4 ) are replaced by 4Fe~(3 ), 1Ca~(2 ) by 1Fe~(3 ), and 1Fe~(3 ) occupies one octahedron hole; Fe~(2 ) mainly replaced Ca~(2 ). Spectroscopic Study has indicated there may be extream distortion and higher orientation disorder in (SiO_4) tetrahedron, the reduction of lattice order and translation symmetry by results of ionic replacements of Fe~(3 ) or Fe~(2 ) in C_3S crystal lattice.  相似文献   

18.
煤矸石代替黏土生产水泥可行性分析   总被引:2,自引:0,他引:2  
为了研究煤矸石代黏土生产水泥的可行性,对10个省份28个矿点进行取样,开展煤矸石特性分析.分析结果表明,煤矸石具有高灰分、高硫分和低热值等特点,化学成分与黏土相近,还含有较丰富的微量元素和矿物组成.对煤矸石、中钙石灰石和硫酸渣等配料进行煅烧试验,试验表明,煤矸石在煅烧时,微量元素和矿物释放其储存的地质能量,加速促进硅氧键的断裂,比黏土配料更早生成硅酸三钙、硅酸二钙和铝酸三钙等水泥熟料矿物.煅烧过程中放出的二氧化硫与钙铝氧化物反应形成早强硫铝酸盐水泥熟料矿物,从而减少硫化物对环境的污染.  相似文献   

19.
The initial hydration of steel slag with high Al2O3 content and its influence on the initial hydration of cement were investigated in this study. Steel slag with high Al2O3 content may contain much calcium aluminate mineral but very little gypsum. The steel slag hydrates much more quickly than cement in the initial hydration period, producing many flake products which have a great influence on the fluidity, initial setting time, and adsorption level of superplasticizer of paste. Replacing part of cement by steel slag with high Al2O3 content can change the hydration condition of calcium aluminate mineral of the cement by decreasing the gypsum to calcium aluminate mineral ratio, resulting in accelerating the hydration rate of calcium aluminate mineral in the initial hydration period. Paste containing steel slag with high Al2O3 content has a shorter initial setting time, higher adsorption level of superplasticizer, and greater loss in fluidity than the pure cement paste.  相似文献   

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