【作者】 陈鹏；

【导师】 陈剑雄；

【作者基本信息】 重庆大学 ， 材料科学与工程， 2007， 硕士

【摘要】 本文研究的硅铝酸盐混凝土是以含无定型的SiO₂、Al₂O₃为主要成份的锂渣,通过适当的物理化学改性工艺以改变锂渣酸性渣体的性质,得到以非稳定态（无定型及亚结晶态）的硅酸盐、铝酸盐及硅铝酸盐为主的改性粉体,以适宜的碱组分激发,制成水硬性胶凝材料的通称。主要研究三类硅铝酸盐混凝土:石灰—物理改性锂渣轻质硅铝酸盐混凝土（LWEC）,碱矿渣—化学改性锂渣硅铝酸盐混凝土（JHEC）和硅铝酸盐碱加气混凝土（AHEC）。采用物理化学两种方法,对锂渣进行改性。物理改性为:通过加入适量石灰,及钙盐外加剂改善锂渣碱性和粉磨效果,通过机械粉磨,得到改性粉体。采用常压干湿热养护,将得到的物理改性粉体作为胶凝材料制作成轻质硅铝酸盐混凝土（LWEC）。锂渣化学改性工艺采用:加入改性剂,经1000℃左右煅烧,急速冷却后,进而粉磨成一定细度的化学改性粉体。微观研究表明,绝大部分粉体颗粒呈细分散状态非晶质玻璃体,颗粒较细呈类球状,分布均匀,整体呈蜂窝状结构。和原状锂渣相比,已经完全改变了微观形貌和化学成分。将该化学改性粉体加入碱矿渣砂浆中（JHEC）,能明显改善碱矿渣砂浆的性能。也可以作为碱矿渣加气混凝土主要组分之一,制备硅铝酸盐加气混凝土（AHEC）。本文主要研究结果如下:①LWEC在干湿热带模养护条件下,抗压强度可达到40～50MPa左右,抗折强度可达9～11Mpa左右,试件表干密度为1600kg/m³左右。最佳养护制度:升温速度30℃/h,恒温温度180℃,恒温时间4h。与同等级强度蒸压养护的轻质灰砂硅酸盐混凝土试件能耗方面比较,常压干湿热养护比蒸压湿热养护要节省45%以上的能源,表干密度降低11%左右。②高温化学改性锂渣最佳的工艺参数:煅烧温度1000℃,煅烧时间45min。煅烧后粉体经过急速冷却,粉磨15min后得到化学改性粉体。其比表面积为7350cm²/g～8348 cm²/g,堆积密度为0.7g/cm³～0.8g/cm³,密度为2.1g/cm³～2.3g/cm³。③在JHEC中掺入化学改性粉体AF3,能改善砂浆性能。当AF3掺入为10%～20%时,增强碱矿渣砂浆的强度,凝结时间延长。当AF3掺入30%时,28d强度发展比纯矿渣砂浆好,但是56d强度两者持平。随着掺量增加,超过40%后,砂浆强度开始下降。当AF3掺入60%,28d强度抗折,抗压强度强度等级与32.5波特兰水泥相当。经过实验发现,通过加入化学改性粉体能抵制碱矿渣胶凝材因干燥引起的收缩,起到了对碱矿渣胶凝材料的综合改性。④通过X衍射和电镜扫描对JHEC净浆进行了微观分析,发现水化产物以沸石类矿物为主,从水化产物结晶度来看,加入AF3的JHEC净浆,使矿渣颗粒水化更加彻底,更利于胶凝材料形成一个整体。⑤成功地制成了硅铝酸盐碱加气混凝土（AHEC）,得出最佳的生产工艺参数。在实验中采用三种养护方式,蒸汽养护,热水养护和标准养护,分别得出了试件最佳的养护制度。通过实验发现经过蒸汽养护得到的试件性能较其它两种养护方式好。⑥测试了经过蒸汽养护的AHEC试件干缩性能,吸水率,以及试件导热性能,得出性能指标均很好满足蒸压加气混凝土砌块国家标准（GB 11968-2006）。本工作主要研究如何高效利用酸性渣体,使大量堆积锂废渣,得到新的利用,提高经济附加值。总结了关于典型酸性渣体改性方法及其应用的规律性结果,对工业酸性废渣的开发和应用具有指导作用。因而具有良好的实用意义。更多还原

【Abstract】 This paper studies that lithium slag with main ingredients of amorphous silica, alumina, through appropriate physical and chemical modification process to change the nature of lithium acid residue, to be modified powder with non-steady state (amorphous and crystalline - state) silicate, aluminate and silicate, appropriate to the Alkali activation,be made hydraulic cementitious materials.Three major studies of alumino- silicate concrete : the light alumino- silicate concrete of lime-physical modification (LWEC); alkali alumino- silicate concrete of slag-chemical modification of lithium slag(JHEC); alkali alumino- silicate aerated concrete (AHEC).Using two methods of physical and chemical, the residue of lithium is to be modified. Modification of the physical: adding some lime, and calcium additive to improve the alkaline and reform effect by mechanical grinding is to be modified powder.Using atmospheric dry cured, the physical modified powder as a cementitious material is made to produced light silicate concrete (LWEC).Chemical modification: by modifier to Li slag, after high calcining temperature 1000℃modified, then rapidly cooling and grinding, has to be modified chemical powder. Microscopic observations show: particles are smaller and spherical category, Overall show honeycomb structure. Compareing with Li slag, has been a complete change in the morphology. Chemical modification powder drop alkali slag mortar, can significantly improve the performance of alkali slag mortar (JHEC).Chemical modification powder can be used as the main components ,to prepared alkali alumino- silicate aerated concrete (AHEC).Results of this study are as follows:①Lightweight high strength concrete of lithium aluminate of the physical modification of the lithium slag in the atmospheric dry-curing conditions, compressive strength can achieve about 40～50MPa , flexural strength up about 9～11Mpa. Finally prepared lightweight high strength concrete is about 1600kg/m~3 dry density. The optimum parameters: the heating rate of 30℃per hour, the lasting temperature of 180℃, the lasting temperature for 4 hours. Initial energy consumption Calculation, with the same level of intensity autoclaved light gray sand concrete , atmospheric dry -wet cured than autoclaved cured to save more than 45% of energy, lower around 11% dry density. ②Experimental results show that Calcined modified lithium slag optimum process parameters is, calcination temperature of 1000℃, calcination time of 45min,after rapid cooling and grinding 15min to be modified products. The powder is fine, specific surface area 7350cm~2/g～8348 cm~2/g.Powder packing density is 2.1 g/cm~3～2.3g/cm~3, density of 2.4g/cm~3 -2.6 g/cm~3.③Chemical modification powderAF3 by adding alkaline slag mortar(JHEC), the mortar can improve performance. When the incorporation of modification powder from 10% to 20%, it will boost alkaline slag mortar strength and extend time. When the incorporation of 30% modified powder, the concrete 28d strength development better than pure alkaline slag mortar, but almost 56d strength of the development. The modification powder increased gradually more than 40%, the mortar strength begin to decline. While the incorporation of 60% modification powder , bending and compressive strength is low 46.2%,38.4% than the pure mortar slag. But specimens strength is with strength32.5 grade Portland cement.The study found that the powder can significantly inhibited dry shrinkage, caused by dry slag cementitious materials. By calcinations, the modified powder reached the right synthetic modification slag cementitious materials.④Through X-ray Diffraction and Scanning Electron Microscopy to view, it find that in the JHEC paste the hydration product is most zeolite minerals. From the crystallization, in the JHEC paste, slag particles hydration is more thoroughly and more conducive cementing to form a whole.⑤Successfully the work is make to get the alkali silicate Aerated Concrete (AHEC),to get the optimum process parameters. In the experiment steam conservation, water conservation and standards conservation is used as three conservation approaches in the experiment and is drawn three optimization conservation parameters approaches. It found that steam conservation is best than the other two.⑥After testing, it shows that shrinkage properties, water absorption, water conductivity and thermal properties of the steam conservation specimen are meet the autoclaved aerated concrete block national standard (GB 11968-2006).The main study how efficient to use acidic residue, accumulation a large number of lithium is to new use, improve the added economic value.Sum up the typical acidic residue on the modified method and its application of the law, Guidance on acidic industrial waste to the development and application. So it has a good practical significance更多还原