比表面积对水泥强度及水泥磨台时产量的影响

众所周知，水泥比表面积对水泥强度及水泥磨台时产量影响较大，在合适的范围内水泥比表面积越高，强度也越高，但比表面积控制得越高，水泥磨台时产量越低。因此，如何从技术经济的角度，在保证水泥质量的前提下，合理地控制水泥比表面积，对提高水泥磨产量，提高经济效益，显得十分重要。本文通过在3．0m×11m一级闭路水泥磨上进行跟踪性生产试验，并结合自己多年来的磨机管理经验，对此进行了初步的探讨，供同行们参考。1试验系统磨机及配套设备规格、型号见表1。表1磨机及配套设备规格、型号2试验方法（1）控制出磨水泥比表面积分别为290…     

提高比表面积生产高标号水泥

1概述 我公司 4000t/d熟料新型干法生产线配备了年总产 137万 t水泥的两套相对独立的水泥粉磨系统。该系统采用辊压机作预粉磨、球磨机作终粉磨,用 O－ SEPA高效选粉机作分级设备。单套粉磨系统流程见图 1,两套粉磨系统的主机配置见表 1。 　　从表 1可知,单套粉磨系统的设计能力为生产比表面积 (勃氏 )3200cm2/g水泥 120t/h。随着经济的发展和市场需求的变化,我公司利用现有设备和普通熟料先后开发生产了勃氏比表面积高达 3800cm2/g左右的 625R水泥和按美国标准生产的 C150－ typeⅠ水泥 (以下简称 ASTmⅠ型 )及更高标号的 C150－…     

球改锻提高水泥比表面积

0前言 江西万年青水泥股份有限公司瑞金水泥厂(以下简称我公司)#4,#5两台Ф3.5 m×11 m闭路水泥磨配套的Ф4 m选粉机分别于1993年和1998年进行了技术改造,取得了良好的技改效果.技改后磨机台产有很大提高,两台磨平均台产达到54.52t/h,超过设计能力10%,极大地缓解了我公司#3窑熟料产量与水泥制成系统不匹配的问题.但在近几年生产中抽样检测发现,两台磨的产品细度不一致,在相同比表面积情况下,#5磨4900孔筛余值要比#4磨小得多,但其水泥性能(主要是早期强度)差于#4磨.     

小型预热器窑采用无烟煤煅烧水泥熟料

0引言 越南Kienkhe水泥公司原有一条240t／d机立窑生产线，2003年8月由我院提供设计及部分关键设备，并负责设备安装、调试，将烧成系统改造为300t／d五级旋风预热器窑，采用100％无烟煤煅烧，其生料磨、水泥磨系统不变。2005年1月生产线点火试生产，2005年5月通过168h考核。     

不同窑型水泥熟料共同粉磨对水泥性能的影响

实验室测试了共同粉磨不同窑型熟的水泥物理性能、颗粒级配和水化放热速率。结果表明,回转窑和立窑熟料混合,改善了水泥熟料的易磨性,水泥的标准稠度用水量随着立窑熟料掺入量和粉磨时间的延长而增大。泌水性得到明显改善,颗粒级配更加合理,水泥强度提高,特别是３ｄ的抗压、抗折强度,它并不是两种水泥强度的简单加权,而是表现出增强作用,混合水泥熟料放热量、放热速率界于两者之间。     

立窑熟料与立波尔窑熟料混合粉磨的水泥特征

0 引言 立窑熟料和立波尔窑熟料因煅烧方式不同,岩相结构和矿物组成及易磨性存在差别。若二者以不同的比例混合粉磨,制得的水泥颗粒及其物理性能有何特点呢?平顶山水泥厂原有两条Φ4×60m的立波尔窑生产线,年产硅酸盐熟料60万t,1998年扩建一条Φ3×10m的机立窑生产线,年产熟料8万t。为了研究两种不同窑型生产的熟料混合磨制的水泥的性能,我们利用本厂生产的立窑熟料和立波尔窑熟料,按不同的比例相混合,磨制成不同编号的水泥,分析其颗粒特     

降低出磨水泥温度改善水泥性能

<正>0前言我公司2500t/d新型干法水泥生产线熟料烧成采用Φ4.0m×60m回转窑带五级旋风预热器和高原型NDSP52分解炉。2007年11月点火试生产以来,经过对工艺设备的技术改造和工艺参数的不断优     

我厂提高出磨水泥质量的措施

0前言随着我国水泥行业的质量标准逐步和世界接轨,对水泥的早期强度要求有了较大的提高,这就给一些水泥厂,尤其是中小型水泥厂的生产带来了很大的困难。在熟料质量相对稳定的条件下,比表面积是影响水泥早期强度的重要因素,因此,提高水泥比表面积已成为一些水泥厂迫在眉捷的问题。现就我厂oZ．4mX14m开流水泥磨提高比表面积的措施作一介绍。另外,出磨水泥温度过高也一直困扰着许多水泥生产厂家,本文将介绍一种降低出磨水泥温度的简单方法,供参考。1提高出摩水泥比表面积的具体措施和效果磨机的有关工艺参数见表回。（l）改变磨机的…     

二级配球提高水泥磨产量的体会

１概述我厂回转窑车间Φ２４ｍ×１３ｍ水泥磨为四仓管磨机,电机功率为８００ｋＷ,设计装球量为６５ｔ,一、二仓装球,三、四仓装段,均采用多级配球。自１９９５年５月投产以来,磨机长期处于低产、高消耗状态,台时产量仅在１５ｔ／ｈ左右。其后,对球径级配进行多...     

Porosity and specific surface area of Roman cement pastes

Mercury porosimetry, water vapour and nitrogen adsorption were used to follow the hydration of Roman cements — belite cements calcined at low temperature. Generally, unimodal distribution of pore sizes was observed, with the threshold pore width decreasing considerably with increasing curing time. An open porous structure with the threshold pore diameter between 0.2 and 0.8 μm and the specific surface area not exceeding 20 m²/g was produced at early ages when quick growth of the C–A–H phases is observed. The surface area reached up to 120 m²/g and the threshold pore width shifted to around 0.02 μm when the subsequent formation of C–S–H gel filled the larger pores. Both mercury porosimetry and water vapour adsorption were found to be capable of following the progress of hydration of the Roman cements with high reliability at least for a comparative evaluation of historic Roman cement mortars and repair materials used in restoration projects.     

φ2.4m×12m开流磨稳定生产P·O 42.5级水泥的技术措施

我公司现有2台Φ2.4m×12m开流高产磨,于1998年10月建成投产。生产P·O32.5级水泥,台时产量一直维持在23～24t/h(80μm筛筛余为4%～6%)。2004年6月中旬,公司与某一高速公路指挥部签订了总量达5万tP·O42.5级水泥的购销合同,2004年7月初在对水泥粉磨系统工艺参数、细度控制指标等未做任何调整(只将混合材掺入量适当减少)的情况下组织生产P·O42.5级水泥,结果很不理想。后经采取了一系列有效措施,于8月开始稳定生产出合格的P·O42.5级水泥。1熟料理化性能2003年3~6月,我公司在合肥水泥研究设计院的技术帮助下,将原600t/d预热器窑改造成120…     

Improved electrochemical performance of LiFePO4 by increasing its specific surface area

Cathode material LiFePO₄ with an excellent rate capability has been successfully prepared by a simple solid state reaction method using LiCH₃COO·2H₂O, FeC₂O₄·2H₂O and (NH₄)₂HPO₄ as the starting materials. We have investigated the effects of the sintering temperature and mixing time of the starting materials on the physical properties and electrochemical performance of LiFePO₄. It was found that the rate capability of LiFePO₄ is mainly controlled by its specific surface area and it is an effective way to improve the rate capability of the sample by increasing its specific surface area. In the present study, our prepared LiFePO₄ with a high specific surface area of 24.1 m² g⁻¹ has an excellent rate capability and can deliver 115 mAh g⁻¹ of reversible capacity even at the 5 C rate. Moreover, we have prepared lithium ion batteries based on LiFePO₄ as the cathode material and MCMB as the anode material, which showed an excellent cycling performance.     

Effect of increasing anode surface area on the performance of a single chamber microbial fuel cell

The anode material and its configuration represent an important parameter in a microbial fuel cell (MFC), as it influences the development of the microbial community involved in the electrochemical bio-reactions.The aim of this work was to evaluate single chamber microbial fuel cells (SCMFCs) with high anode surface area, achieved by using packed beds of irregular graphite granules. The performance of the SCMFC with the packed bed anode configuration was studied using a mixed microorganism culture from real wastewaters in batch and continuous mode operation.The current output was found to increase with the increase in thickness of the anode bed and with the approximate anode area. The best performance was obtained with the 3 cm anode bed depth SCMFC. When the latter was operated in batch mode, Coulombic efficiencies varied from 30% to 74%, depending upon feed COD. In continuous mode operation, the COD removal was 89% and Coulombic efficiency 68% with a feed COD of 50 ppm, and at a flow rate of 0.0028 cm³ min^?1. Power performance was also reasonable with a volumetric power density of 1.3 W m^?3, with respect to the net anodic volume (12.5 cm³). Comparable performance was achieved with real wastewater. Over the duration of tests current output was stable. The investigation performed in this study represent a step forward for implementing real applications of MFC technology. A model of the current distribution in the packed bed electrode was applied, which correlates the effective utilization of the electrode to its specific area, solution conductivity and slope of the polarization curve. This model could function as a starting point in designing appropriate electrode geometries.     

水泥比表面积测定标准试验结果分析与探讨

相对旧标准而言,GB/T8074-2008（（水泥比表面积测定方法勃氏法》修订的核心内容是：1）改变了试样空隙率;2）在勃氏透气仪的基础上增加了自动比表面积仪;3）试验用标准粉发生了变化;4）为统一压实力度,以2000g砝码作为压实捣器。标准的上述变化,减少了试验误差,量化了比表面积测定的操作过程,使试验结果趋于稳定,测量过程更加规范化。     

熟料和矿渣比表面积与水泥浆体流变性的线性关系

在单掺矿渣的水泥中,熟料和矿渣比表面积的增大,均降低了水泥净浆的流变性;在试验条件下得出,浆体流动度L与比表面积S呈线性关系:L矿渣,30min=110-0.041(S-326),L熟料,30min=121-0.147(S-265);从直线斜率上看出,熟料对水泥净浆流动度的影响远大于矿渣的影响程度。     

Silica foams with ultra-large specific surface area structured by hollow mesoporous silica spheres

Ceramic foams with multi-scale pores and large specific surface area have received extensive attention due to their unique structure and superior properties. Considering that there are still challenges to synthesize porous ceramics with large specific surface area, a novel ceramic foam material with ultra-large specific surface area has been prepared using hollow silica mesoporous spheres (HMSSs) as building block in this work. These building blocks were made weakly hydrophobic in order to produce HMSS particle stabilized foams. The foams exhibit a uniform primary macropore structure, which is composed of a three dimensional HMSS-assembled network, via HMSS-stabilized foams. The influence of sintering temperature on the microstructure and properties of HMSS foams is investigated. The HMSS foams exhibit highest specific surface area of 1733 m²/g, attributed to the radial mesopores in HMSS shell, when sintered at between 500°C and 800°C. This specific surface area is much higher than that of existing ceramic materials. The uniform pore structure and ultra-large specific surface area make it a promising lightweight material in potential application fields, including catalyst, adsorption, fire-resistant thermal insulation, and load and control release system.     

高比表面均苯型聚酰亚胺的合成与研究

本实验采用正向加料工艺,将二酸酐加入已溶解的二胺中,通过两步法控制反应温度、反应物以及脱水剂用量等条件,以此来控制聚合物的分子量。发现控制反应的温度,其中包括水浴反应与加热反应两个阶段,以及控制脱水剂用量这两种方式是提升均苯型聚酰亚胺性能的有效方式。