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国内较多的新型干法水泥生产线的尾排烟气中,二氧化硫含量远远高于国家标准。为实现达标排放,需要为水泥窑窑尾配套脱硫系统,石灰石-石膏湿法脱硫技术已广泛应用于新型干法水泥生产线中。文章重点介绍水泥生产线石灰石-石膏湿法脱硫工艺流程和工艺设备。 相似文献
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燃煤烟气排放的二氧化硫和氮氧化物是重要的大气污染物质,同步脱硫脱硝技术是目前研究的热点。本文主要从吸收剂的成本及脱硫脱硝产物的可资源化利用两个方面对目前广泛研究的湿法同步脱硫脱硝技术进行了综述,并指出资源化同步脱硫脱硝技术是研究的发展趋势。 相似文献
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随着生态文明建设步伐的不断加快,人们对大气环境质量的要求越来越高,工业烟气中的二氧化硫作为主要污染物之一,其控制和减排对改善环境质量极为重要。综述了国内外湿法脱硫技术的研究进展,介绍了传统湿法脱硫技术的原理和应用现状,提出了主要存在的问题,比如:脱硫吸收剂的不可持续性和区域限制性、脱硫副产物的资源化利用及环境污染、脱硫系统设备的可靠性和运行的经济性等问题。对新型湿法脱硫技术的原理和研究重点进行了分析,指出研制并推广环境友好型和可循环利用的新型脱硫吸收剂、大力发展传统湿法脱硫副产物资源化利用技术、加快新型湿法脱硫技术成果转化是未来湿法脱硫技术的发展方向。 相似文献
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研究了在不同温度下处理的脱硫石膏对矿渣水泥若干性能的影响,确定其在水泥基材料中循环利用的可行性。研究结果表明,经低温烘干焙烧处理的脱硫石膏,掺入到矿渣水泥中并控制适当的SO3掺量,水泥凝结时间正常,强度略有提高,并且明显降低了硬化水泥浆体的失水率和干缩率,可以有效防止收缩裂缝的产生:并进一步探讨了脱硫石膏对矿渣水泥性能的影响机理。 相似文献
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以脱硫建筑石膏为主要胶凝材料,研究无机改性剂粉煤灰和水泥、复合激发剂、有机硅防水剂对脱硫建筑石膏耐水性的影响。实验结果表明,单掺粉煤灰和水泥对脱硫建筑石膏体系的耐水性提高幅度不大。复掺粉煤灰、水泥和复合激发剂后,可以获得6 MPa以上的抗折强度,22 MPa以上的抗压强度,0.6以上的抗折软化系数,但抗压软化系数和吸水率与单掺体系相比差别不大。在复掺最优配方的基础上添加有机硅防水剂,在防水剂掺量为0.8%时,其复合脱硫石膏试块的抗折软化系数0.756,抗压软化系数0.791,分别提高了64.3%和108.1%,吸水率仅为3.7%,显著地提高了脱硫石膏的防水性能。 相似文献
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石膏的耐水性能差限制了其在建筑领域的应用,本文以郑州地区脱硫建筑石膏为主要原料,普通硅酸盐水泥为辅料制备了耐水性能好且成本较低的改性脱硫建筑石膏,系统研究了水泥用量对样品水化后的物理性能、物相组成和显微结构的影响。结果表明,随着水泥掺量的增加,其水化后生成的钙钒石(AFt)、氢氧化钙(CH)和水化硅酸钙(C-S-H)凝胶逐渐增多并填充气孔,使样品水化后的吸水率呈先降低后升高的趋势,而软化系数、接触角和硬度则呈相反的趋势,当水泥的用量为18%(质量分数)时,样品耐水性能较佳。本研究为制备耐水性能好且经济环保的脱硫建筑石膏及其制品提供了技术依据,并对脱硫石膏的推广应用及建材行业的绿色发展具有重要意义。 相似文献
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Alternative calcium-sulfate-bearing materials as cement retarders: Part II. FGD gypsum 总被引:1,自引:0,他引:1
G. Tzouvalas 《Cement and Concrete Research》2004,34(11):2119-2125
The aim of this paper is to investigate the possible displacement of natural gypsum (CaSO4·2H2O) in cement with an alternative setting retarder, such as the industrial by-product derived from flue gas desulfurization process called FGD gypsum. These calcium-sulfate-bearing materials (CSBM), alone or in mixtures, were ground with clinker both in laboratory and industrial scale to examine their influence on the physical and mechanical properties of cement, as well as on the industrial production line of cement. From the present work, it is extracted that the use of mixtures of sulfate-bearing materials with gypsum seems to be advantageous for the actual control of setting time. The addition of FGD gypsum increases setting time without affecting compressive strength profile. During the industrial trial, the formation of hemihydrate form of calcium sulfate dihydrate has a profound regulatory effect on the setting and strength performance of the cement partially replaced with FGD gypsum. 相似文献
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利用正交实验研究了硅酸盐水泥和其他两种矿物组分复合激发对脱硫石膏-矿渣体系强度的影响,用SEM、XRD分析了水化样品的微观结构.研究结果表明:硅酸盐水泥等多组分复合激发下,脱硫石膏-矿渣体系在水中标准条件养护,3 d抗压强度达17 MPa以上,28 d抗压强度达58 MPa以上.复合激发剂3种组分的优化组合为6:6:5,复合激发剂的用量为脱硫石膏-矿渣体系质量的17%左右.脱硫石膏-矿渣体系在复合激发条件下的水化产物主要是钙矾石和C-S-H.大量钙矾石、石膏晶体相互交叉连生,未水化石膏、矿渣颗粒所填充其间,在C-S-H凝胶的胶结下,形成了较为致密的晶胶搭配构成的微观结构. 相似文献
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脱硫石膏联产水泥与硫酸技术 总被引:1,自引:1,他引:0
结合鲁北集团60kt/a水泥-40kt/a硫酸中试装置数据,介绍用电厂烟气脱硫石膏联产水泥与硫酸的原料性质、工艺流程、控制指标及成本构成。指出用脱硫石膏联产水泥与硫酸具有技术和经济可行性,既可减少环境污染,又可实现废物的资源化利用。 相似文献
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喷雾干燥法与石灰石石膏法脱硫工艺比较 总被引:1,自引:0,他引:1
喷雾干燥法与石灰石石膏法是目前应用最广泛的两种脱硫工艺,两者在脱硫性能、煤种及机组适应性、运行维护费用等方面各有优劣。喷雾干燥法适合低硫煤、低效率、中小机组,且运行维护费较低;而石灰石石膏法则能满足高硫煤、高效率、大机组的要求,但运行维护费较高。 相似文献
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Environmental chamber measurements of mercury flux from coal utilization by-products 总被引:1,自引:0,他引:1
An environmental chamber was constructed to measure the mercury flux from coal utilization by-product (CUB) samples. Samples of fly ash, FGD gypsum, and wallboard made from FGD gypsum were tested under both dark and illuminated conditions with or without the addition of water to the sample. Mercury releases varied widely, with 7-day experiment averages ranging from −6.8 to 73 ng/m2 h for the fly ash samples and −5.2 to 335 ng/m2 h for the FGD/wallboard samples. Initial mercury content, fly ash type, and light exposure had no observable consistent effects on the mercury flux. For the fly ash samples, the effect of a mercury control technology was to decrease the emission. For three of the four pairs of FGD gypsum and wallboard samples, the wallboard sample released less (or absorbed more) mercury than the gypsum. 相似文献
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Nikolaos Koukouzas Charalampos Vasilatos 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(1):20-26
BACKGROUND: The aim of this work is to define the chemical and mineralogical composition of the fuel gas desulphurization (FGD) gypsum produced from the Meliti thermal power plant in the region of Florina in North West Greece, in order to investigate potential uses in the cement industry. Mineralogical and microprobe analyses were carried out on FGD gypsum samples collected from the Meliti 330 MW lignite‐fired power plant. RESULTS: Results show that the main component of the FGD gypsum is pure mineral gypsum (CaSO4·2H2O). The particle size of the gypsum ranges from 5 to 50 µm and the crystals are mainly of rhomboid shape. Microprobe analysis shows that the concentration of CaO and SO3, which are the main components, range from 31.9%–32.5% and from 45.90–46.40%, respectively. CONCLUSION: This FGD gypsum can easily substitute the natural gypsum used in the production of cement. Copyright © 2007 Society of Chemical Industry 相似文献