本文選題：粉煤灰　切入點：耐火材料　出處：《昆明理工大學》2017年碩士論文　論文類型：學位論文

【摘要】：耐火材料與高溫工業(yè)相輔相成,近年來,隨著高溫工業(yè)逐步轉(zhuǎn)型升級,耐火材料行業(yè)必須緊跟國家“十三五”規(guī)劃制度,堅持開發(fā)與保護并重,杜絕資源浪費,實現(xiàn)節(jié)能環(huán)保仍須要技術進步創(chuàng)新;粉煤灰是由火力發(fā)電廠所產(chǎn)生的固體污染物,我國堆放大量的粉煤灰不僅侵占了寶貴的土地資源,而且給土壤環(huán)境、水體環(huán)境和大氣環(huán)境帶來了不同程度的污染;煤矸石、鋁灰、尾礦石等工業(yè)固廢同樣對環(huán)境構成巨大威脅。粉煤灰中含有大量的有價組元,Al2O3和SiO2二者總質(zhì)量高達60%以上,也是耐火材料中莫來石組分的主要原料。本研究以粉煤灰為主要原材料,并通過混合多種工業(yè)固廢制備出性能優(yōu)良的高附加值耐火材料;并研究了燒結溫度、原料成分比例、成型壓力等因素對耐火材料的性能影響;利用多元相圖結合掃描電鏡(SEM)對耐火材料的微觀形貌特征進行分析。結果表明,使用粉煤灰、鋁灰、煤矸石制備了粘土系耐火材料,粉煤灰添加量為50%、鋁灰添加量30%、煤矸石20%,燒結溫度在1300℃保溫10小時的條件下得到顯氣孔率26.43%、常溫耐壓強度46MPa、常溫抗折15MPa、耐火度1520℃、加熱永久線變化+0.3%的耐火材料,該制品的物理性能和使用性能良好,符合國家耐火材料使用標準(YB/T5106-2009)。通過對相同組分、不同燒結溫度耐火材料進行XRD分析研究發(fā)現(xiàn),樣品內(nèi)部主要晶相為莫來石相和剛玉相,其中,莫來石相的含量隨著燒結溫度的升高而增多。根據(jù)均勻試驗的結果得知,當燒結溫度1300℃、成型壓力為20MPa時,耐火材料的力學性能和物理性能最佳;成型壓力對耐火材料的顯氣孔率、體積密度及常溫耐壓強度、常溫抗折強度影響較大,燒結溫度則對耐火材料的耐火度及加熱永久線變化影響較大。以多元相圖所提供的“共晶”理論作為理論依據(jù),結合微觀結構圖像發(fā)現(xiàn),Al2O3含量直接影響著耐火組分的形態(tài)及晶型變化。
[Abstract]:Refractories and high-temperature industries complement each other. In recent years, with the gradual transformation and upgrading of high-temperature industries, the refractory industry must closely follow the national "13th Five-Year Plan" system, attach equal importance to development and protection, and put an end to waste of resources. The realization of energy saving and environmental protection still needs technological progress and innovation. Fly ash is a solid pollutant produced by thermal power plants. A large amount of fly ash in our country not only encroaches on valuable land resources, but also gives soil environment. Industrial solid waste of coal gangue, aluminum ash and tailings also poses a great threat to the environment. Fly ash contains a large number of valuable components, such as Al _ 2O _ 3 and SiO2, which have a total mass of more than 60%. It is also the main material of mullite composition in refractories. In this study, fly ash was used as the main raw material, and high value-added refractories with excellent properties were prepared by mixing various industrial solid wastes, and the sintering temperature and the proportion of raw materials were studied. The influence of molding pressure and other factors on the properties of refractories was analyzed by means of multicomponent phase diagram and scanning electron microscope (SEM). The results showed that clay refractories were prepared by using fly ash, aluminum ash and coal gangue. The amount of fly ash is 50, aluminum ash is 30, coal gangue is 20, sintering temperature is 1 300 鈩，

本文編號：1625768