【作者】 徐子芳；

【导师】 张明旭；

【作者基本信息】 安徽理工大学 ， 环境工程， 2010， 博士

【摘要】 随着人们生活水平的提高、能源问题的日益严峻,人们对居住房屋的保温性要求相应提高,保温材料的研究与开发成为建筑材料领域的热点话题,同时利用废弃物开发研制新型保温材料又是热点中的重中之重。粉煤灰与废旧聚苯乙烯泡沫(EPS)是环境的两大杀手,如何将其合理利用,变废为宝是开发研制新型材料的新途径。将这两种废弃物应用于保温砌筑砂浆中,发挥其各自的优点,开发出一种新型节能保温墙体材料,达到变废为宝是本文的研究目的。粉煤灰的利用主要是对其活性的利用,特别是作为建筑材料-水泥混凝土的原材料,少用水泥做基础原料,减少了水泥用量,即等于减少了一次资源、能源的消耗,同时也减少了因生产水泥带来的环境污染；废弃聚苯乙烯泡沫塑料因质轻、体积大,在自然界条件下,一、二百年也不降解,造成严重的白色污染,破坏生态环境,但利用其质轻(0.01-0.05g/cm3)、无毒、低吸水性、耐酸碱、耐候、绝热、隔音等性能特点研制保温隔热材料是消除生活垃圾,变废为宝的新途径。本文利用石灰、石膏作为粉煤灰活性的激发剂,加入改性的聚苯乙烯泡沫研制出保温性能和耐久性能皆较为优良的粉煤灰聚苯乙烯保温砂浆及砌块,充分满足我国目前对建筑保温隔热砂浆及建筑保温砌块的要求,属于绿色节能建筑材料。保温砌筑砂浆及砌块所使用的添加剂NF-30主要合成原料采用煤焦化洗油的馏分-洗油,由于洗油与萘属于同类化合物,合成的添加剂不但性能优良而且又是所研制的保温砂浆原料中另一种废弃物的利用。全文对所研制的保温砂浆砌块的原料组成、实验思路、技术手段、水化、硬化等性能都进行了较为全面、系统的研究：(1)综合利用材料测试手段、有机化学、热力学、物相分析、材料物理性能等基础理论,从保温砂浆砌块所使用粉煤灰的物理性质、化学成分、石灰-石膏的物理化学性质及活化机理、废弃EPS的物理化学性质及改性途径,探讨了用粉煤灰和EPS研制保温砂浆及砌块的反应机理及开发自保温砂浆及砌块的可能性；(2)对石灰-石膏激发下的粉煤灰砂浆水化-硬化机理进行了系统研究,采用大量的基本物理性能测试手段分析了激发体系下的砂浆物理性能,用石灰-石膏激发粉煤灰潜在活性,砂浆中以20%-25%的粉煤灰掺量为最佳；(3)借助X衍射、TGA-DTA水化产物热机理分析及水化龄期产物扫描电镜SEM观察显示：石灰对粉煤灰活性激发效果应以CaO含量相等为条件,石膏在Ca(OH)2存在下,与粉煤灰中活性硅铝组分作用形成钙矾石,对粉煤灰水化起硫酸盐激发作用,这种作用会因新生二水石膏的高分散性与高表面活性而更加强烈。粉煤灰与无水石膏的水化相互促进,石灰-石膏对粉煤灰的激发效果早期微弱,后期Ca(OH)2、C-S-H、AFm等水化产物发育良好。石灰-石膏的加入对激发粉煤灰的潜在活性起到了很好的作用；28及60天水化产物形貌显示：一方面石灰-石膏激发了粉煤灰的活性,弥补了水泥砂浆强度损失,另一方面也说明粉煤灰的活性仍没有被完全激发,后期仍有少量活性弱的粉煤灰存在。石灰-石膏激发下的砂浆水化后期界面一定程度趋于规整,其耐候性提高,后期强度相对持久。揭示了研制开发石灰-石膏-粉煤灰砂浆砌块的可能性；(4)保温砌筑砂浆砌块所需外加剂NF-30的合成显示：产品PH值为7—9,磺化时间2.5h,缩合时间为5h,磺化温度160℃,磺化过程中添加氧化剂MO,添加30%洗油合成减水剂NF-30综合性能最佳。NF-30改性水泥混凝土性能显示：分散性好,水泥砂浆水化更快,水化产物更多,提高了早期强度。自制添加剂NF-30与纯萘减水剂性能相当,而原料成本大大降低,开辟了焦化洗油废弃物的利用新途径；(5)对一定级配的粉煤灰-EPS砂浆制作揭示了采用0.16--2.0mm的EPS级配,粉煤灰掺入量为20%,EPS掺量2.0%-2.5%时,保温砂浆的综合工作性能最好；(6)无石灰-石膏的粉煤灰EPS保温砌筑砂浆水化产物TGA-DTA热机理分析和X衍射分析显示：龄期水化过程相对基准砂浆样迟缓,强度较低,但物理性能优于外掺其它保温材料。综合耐久、耐候性能良好,保温性能好[0.455(W/m.K)],揭示了利用粉煤灰和EPS研制保温砂浆砌块的可能性和采用石灰-石膏激发粉煤灰活性的必要性；(7)以石灰-石膏激发粉煤灰潜在活性为前提,利用EPS的保温性,研制综合体系下的多种废弃物同时利用的新型功能材料,配制的保温砂浆最佳粉煤灰和EPS掺量为20%和2.5%,导热系数为0.531W/(m.K),远远低于空白砂浆的导热系数0.938W/(m·K),保温性能优良,完全满足两淮流域地区节能标准规定的传热系数不高于1.5W/(m·K)的要求,同时证实外掺石灰-石膏激发作用下可使保温砂浆砌块结构致密,导热系数略大于无石灰-石膏激发的保温砂浆砌块体系,但综合性能最佳；(8)激发剂作用下的粉煤灰-EPS新型保温砂浆砌块后期强度持久,具有良好的耐酸性、抗冻性,吸湿率低,吸水率小,软化系数较高,属于耐水性材料,具有良好的耐久性能。生产1m3的保温砂浆将消耗掉环境污染物粉煤灰117kg、聚苯乙烯泡沫塑料(EPS)颗粒14.6kg,脱硫石膏29.3 kg,达到了室温条件下同时利用多种废弃物,变废为宝的目的；(9)粉煤灰聚苯乙烯新型自保温砌筑砂浆水化产物X衍射分析显示：早期水化产物种类较多数量较少,尺寸小,发育不完善,水化产物主要是水化铝酸钙(C4AH13)水化硅酸钙(C-S-H)和氢氧化钙(CH)；28天的主要水化产物是水化硅酸钙(C-S-H),水化铝酸钙(C4AH13)、钙矾石(AFt)和氢氧化钙(CH),同时水化石榴石(C3ASH4)和托勃莫来石(Ca(Si5O18H2)-4H2O)增多,晶体发育趋于完善；60天龄期出现数量较多的水化硅酸钙(C-S-H)、钙矾石(AFt)、氢氧化钙(CH)、水化石榴石(C3ASH4)和托勃莫来石(Ca(Si5O18H2)-4H2O)等水化产物,且随龄期的延长,水化产物数量增多,尺寸变大,晶型稳定。进一步说明：石灰、石膏对粉煤灰的激发作用在早期不明显,后期激发作用显著。从微观上验证了用石灰和石膏激发粉煤灰的活性可以弥补由于加入粉煤灰和EPS废弃物引起的强度损失,提高保温砂浆砌块的使用可能性；(10)粉煤灰聚苯乙烯新型保温砂浆SEM扫描分析显示：水化早期(3天),形成了较多的水化铝酸钙、C-S-H凝胶和Ca(OH)2等水化产物,但是它们尺寸较小,发育不完整,以片状结构和纤维状结构为主,空隙率较大。28天水化产物数量增多,不断长大,发育良好,箔片状水化硅酸钙有包裹其它水化产物的趋势,空隙率降低,结构变得致密。水化后期(60天),水泥熟料和粉煤灰均大部分水化,水化反应趋于完全,水化产物数量、尺寸和形态均发展良好,结构致密,孔隙减少,表面变得较为平坦,和宏观物理实验结果一致；(11)粉煤灰聚苯乙烯新型保温砂浆砌块属于新型环保、利废、节能自保温材料,它能很好地适应夏热冬冷地区的气候条件,满足建筑节能的要求。针对两淮地区的气候特点,粉煤灰-EPS保温砂浆砌块出现结露的可能性小,热阻大,热桥现象小于普通承重作用混凝土部分,建筑能耗损失相对少,属于节能墙体材料；(12)粉煤灰聚苯乙烯新型保温砂浆砌块施工工艺属于一次性完成,安全性高,便于推广上述研究工作对进一步综合利用粉煤灰、电场脱硫石膏和生活垃圾废弃聚苯乙烯泡沫奠定了基础,并可为新型节能墙体材料的开发开辟了新途径、新思路,从而可获得显著的经济和社会效益。更多还原

【Abstract】 Along with the improvement of living standard and the increasingly serious problems of energy, people’s request for thermal insulation property of residential houses increases. As a result, the research and development of insulation material has become one of the hot topics in construction material field. At the same time, using waste to develop new function materials is the first priority among the hot topics.The fly ash and the waste extruded polystyrene foam (EPS) are two major killers of environment. One of the new ways to develop new materials is to use it reasonably, changing waste into valuable. This paper aims at developing a new type of energy-saving insulating wall material by applying the two kinds of waste to insulation mortar to make the most of their advantages respectively.The main use value of fly ash is its activity, especially when it is used as the raw material of cement concrete. The cement concrete is one of the most important building materials. With the addition of fly ash, the content of cement will decrease, that is to say, it can reduce the consumption of resource and energy, and reduce the environmental pollution resulted from cement production; Under natural conditions, waste extruded polystyrene foam will not degrade in one or two hundred years because of its light weight and small size, which has increasingly led to serious white pollution and has destroyed ecological environment. However, it has many characteristics, such as light weigh (0.01-0.05g/cm3)、innocuity、low water absorption、acid-alkali resistance、weather resistance、heat insulation、sound insulation, which can be used to develop heat preservation and thermal insulation material to change waste into valuable. This paper uses lime-gypsum as the activator of fly ash, adding with modified extruded polystyrene foam, to develop lime-gypsum- fly ash-EPS insulation mortar with good performances for keeping temperature and durability. This kind of insulation mortar fully meets the demand for building heat preservation and thermal insulation mortar and insulation building blocks, it belongs to green energy-saving building material. The main synthetic raw material of NF-30 admixture that used in insulation mortar is the waste of coal coking--washing oil. Because the washing oil and the naphthalene are similar compounds, the synthetic water-reduce is not only of good properties but also the other waste that added in the insulation mortar block. We studied many aspects of insulation mortar; it included the composition of raw materials、experiment ideas、technical means、hydration、hardening. The detailed description is as follows:(1)Using many basic theories of various subjects synthetically, such as test means、organic chemistry、thermodynamics、phase analysis、physical properties of materials, we discussed the reaction mechanism of insulation masonry mortar consisting of fly ash and EPS and the possibility of developing insulation masonry mortar, according to the physical characteristics and the chemical composition of fly ash、the physicochemical properties and the activation mechanism of lime-gypsum、the physicochemical properties and the modification methods of waste EPS;(2)We studied the hydration and the harden mechanism of fly ash mortar activated by lime-gypsum systematically, and analyzed the physicochemical properties of the mortar by many basic physical and chemical properties test means in activation system. We used lime-gypsum to activate the potential activity of fly ash. We discovered that the optimal amount of fly ash is 20%-25%;(3)The XRD analysis、the TGA-DTA hydration products thermomechanical analysis、the observation of the products of hydration time under SEM show:The activity of fly ash is activated by lime effectively on condition of equal content of CaO. The gypsum reacts with fly ash and forms ettringite in the presence of Ca(OH)2, which is used as a sulphate activator for hydration of fly ash. The activating effect becomes stronger because of the generation of dihydrate gypsum with high dispersibility and high surface activity. The hydrations of fly ash and anhydrite promote each other; the effect of activation of lime-gypsum for fly ash is weak in early age. In later times, the hydration products, such as Ca(OH)2、C-S-H、AFm, develop very well. Lime- plasters plays an important role in the activation for the potential activity of fly ash; the appearances of hydration products in 28 days and 60 days later show: on the one hand, lime-plasters activates the activity of fly ash and compensates for the strength loss of cement mortar; on the other hand, it illustrates that the activity of fly ash is not activated completely, there are still some fly ashes with weak activity in later times. The interface of mortar, activated by lime-gypsum, tends to be orderly in the later hydration period. It has higher weatherability and relative lasting later strength. Moreover, it discovers the possibility of developing the mortar of lime-plasters-fly ash;(4)The synthesis of admixture NF-30 which is required by insulation mortar shows: The water-reducer will get the best comprehensive performances when we add oxidant MO、30% washing oil and control the conditions as follows:PH value is 7-9, sulfonation time is 2.5 hours, condensation time is 5 hours and sulfonation temperature is 160℃. The properties of cement concrete modified by NF-30 are very good:good dispersibility, fast hydration speed, more hydration products, and higher early strength. The homemade NF-30 additive cost little but it has the equal properties to pure naphthalene, which pioneers a new way to utilize waste coking washing oil;(5)The preparation of fly ash-EPS in a certain grain degree shows:Using grain degree of 0.16--2.0mm, adding 20% fly ash and 2.0%-2.5% EPS, the insulation mortar gets the best comprehensive performances;(6)TGA-DTA hydration products thermomechanical analysis and XRD analysis of the fly ash-EPS insulation mortar without lime-gypsum show: Compare to standard mortar sample, the fly ash-EPS insulation mortar without lime-plasters hydrates slowly and has low strength, but its physical properties are better than many insulation materials doped with others:good durability\weather resistance、good performance for keep temperature[0.455(W/m·K)].This reveals the possibility of developing insulation mortar blocks and the necessity of activating the fly ash by lime-plasters;(7) In the premise of activating the potential activity of fly ash by lime-desulfurization plasters, we take advantage of the capacity of heat preservation of EPS to develop a novel functional material. The best proportion is 20% fly ash and 2.5% EPS, and then we obtain the insulation mortar of good properties. Its coefficient of heat conductivity is 0.531W/(m·k), far below that of blank mortar(0.938W/(m·k)), it meets the Energy-saving standard that the coefficient of heat conductivity is not higher than 1.5W/(m·k) in Lianghuai valley. Moreover, it confirms that the activation of lime-gypsum results in the dense insulation mortar, its coefficient of heat conductivity is slightly bigger than that of insulation mortar without lime-gypsum activator, but it has the best comprehensive performances;(8)The fly ash-EPS insulation mortar block has good comprehensive performances under the action of activator.:lasting later strength、strong resistance to acid、excellent frost resistance、low moisture absorption low water absorbability、high coefficient of softening, water resistance and good performance in durability.117kg fly ash and 14.6kg EPS and desulfurization plasters 29.3 kg will consumed to produce Im3 insulation mortars, which utilizes many kinds of wastes simultaneously and changes waste into valuable because both of the two raw materials are environmental pollutants;(9)XRD analysis to the hydration products of the fly ash and styrofoam new insulation mortar shows:In early age, the hydration products are small in quantity, small in size, and they do not develop perfectly, the main hydration products are hydrated calcium aluminate (C4AH13)、hydrated calcium silicate (C-S-H) and calcium hydroxide (CH); 28days later, the main hydration products are hydrated calcium silicate (C-S-H)、hydrated calcium aluminate (C4AH13)., ettringite (AFt) and calcium hydroxide (CH). At the same time, the calcium aluminosilicate hydrate (C3ASH4) and the tobermorite (Ca(Si5O18H2)·4H2O) grow in number and the crystal grows perfectly.60 days later, there are hydrated calcium silicate (C-S-H)、ettringite (AFt)、calcium hydroxide (CH)、calcium aluminosilicate hydrate (C3ASH4) and tobermorite (Ca(Si5O18H2)·4H2O) in large quantities. Moreover, with the prolongation of hydration, there are more hydration products, the crystal grains grow up, and the crystal form is stable. It explains in further steps:the activation effect of lime-gypsum on fly ash is not obvious in early age, but remarkably at a later stage. This confirms that the activity of fly ash activated by lime-gypsum can compensate the strength loss which is caused by adding waste fly ash and EPS, and then the use possibility of insulation mortar increases;(10)SEM scan analysis to fly ash and styrofoam new insulation mortar shows:At early age of hydration (3days), there are hydration products in large quantities: hydrated calcium aluminate> C-S-H gel、Ca(OH)2 and so on, but they are small in size and they do not develop perfectly, the main structure is sheet or fibrous, the void ratio is big.28 days later, there are more hydration products, they grow up continuately and develop perfectly, the void content decreases and the structure become dense. At later period of hydration (60 days later), the cement clinker and the fly ash have hydrated mostly, hydration reaction tends to come to an end, the amount of hydration products increases, the size and the morphology of the hydration products develop perfectly, the structure become dense, the void content decreases and the surfaces become flatter, which is consistent with the results of macroscopical physical experiments;(11)The fly ash and styrofoam new insulation mortar block is a new self-insulation environmental material. It can utilize the waste and save energy. Moreover, it can suit the climatic conditions in hot summer and cold winter region and can meet the demand for energy efficiency in buildings. According to the climate characteristics in Lianghuai valley, the possibility that the fly ash-EPS insulation mortar block appears condensation is low, it has large heat resistance, its heart bridge is less than that of general bearing concrete, there is less building energy loss and it belongs to engry-saving building products;(12) The processing technology of the fly ash and styrofoam new insulation mortar block is completed all at once, with high security, so it is easy to promote.The research work lays the foundations for further utilization of fly ash、desulfurization plasters and extruded polystyrene foam;it opens up the new way to develop new energy-efficient wall materials at the same time. Thereby, this material has good economic and social benefit;更多还原