硅質(zhì)尾礦火山灰活性的機(jī)械力化學(xué)活化研究
發(fā)布時間:2018-06-12 23:47
本文選題:硅質(zhì)尾礦 + 機(jī)械力化學(xué)活化 ; 參考:《山東科技大學(xué)》2017年碩士論文
【摘要】:硅質(zhì)尾礦作為我國選礦尾礦的主要類型之一,其化學(xué)成分以SiO2、Al2O3為主,這與火山灰質(zhì)材料近似,具備與Ca(OH)2反應(yīng)生成水硬性物質(zhì)的潛在性能。本文以激發(fā)硅質(zhì)尾礦的火山灰活性為目的,研究機(jī)械粉磨、化學(xué)激發(fā)劑對硅質(zhì)尾礦火山灰活性的活化作用,以及活化尾礦在尾礦復(fù)合水泥中的應(yīng)用。機(jī)械粉磨研究表明,尾礦的火山灰活性隨其比表面積的不斷增加而顯著增強(qiáng)。未粉磨時,尾礦的比表面積為233.20m2/kg, 28d活性指數(shù)僅為53.89%,當(dāng)粉磨至5min,尾礦的比表面積達(dá)到495.10m2/kg,28d活性指數(shù)達(dá)到65.65%,粉磨至45min,在比表面積為849.40m2/kg, 28d活性指數(shù)達(dá)到峰值為80.94%。在尾礦與粉煤灰混合研磨試驗中,比例為1: 1時,比表面積達(dá)到1169.80m2/kg,28d抗壓強(qiáng)度就可以達(dá)到50.25MPa,28d活性指數(shù)為94.56%,此數(shù)據(jù)明顯高于尾礦單獨的粉磨活性(尾礦單獨粉磨時,比表面積為1161.70m2/kg時,28d抗壓強(qiáng)度為37.61MPa,28d活性指數(shù)為73.78%)。CaO和CaCl2對硅質(zhì)尾礦混合材料具有較好的早強(qiáng)作用,CaO的適宜摻量為2%,此時試樣的比表面積為880.40m2/kg,3d抗壓強(qiáng)度達(dá)到22.25MPa,28d活性指數(shù)為81.88%; CaCl2的適宜摻量為1%,此時比表面積為903.90m2/kg, 3d抗壓強(qiáng)度達(dá)到22.14MPa,28d活性指數(shù)為81.74%。通過活化尾礦在尾礦復(fù)合水泥中應(yīng)用性能的研究,發(fā)現(xiàn)摻加尾礦后水泥的凝結(jié)時間伴隨著尾礦的比表面積增加而逐漸降低,體系中的水泥標(biāo)準(zhǔn)稠度用水量也逐漸增大。在尾礦比表面積達(dá)到840.30m2/kg,摻加量為30%時,可以滿足P·Ⅱ425要求,28d的抗折、抗壓強(qiáng)度為6.86MPa、43.91MPa,凝結(jié)時間為201min、253min,標(biāo)準(zhǔn)稠度用水量為28.20%,安定性合格;將尾礦與粉煤灰進(jìn)行復(fù)配比例為1: 1用作復(fù)合水泥的混合材料,比表面積達(dá)到1175.50m2/kg時,滿足P·Ⅱ425要求混合材料的摻加量可以達(dá)到50%,水泥28d的抗折、抗壓強(qiáng)度為7.09MPa、43.77MPa,凝結(jié)時間為237min、311min,標(biāo)準(zhǔn)稠度用水量為29.80%,安定性合格。
[Abstract]:As one of the main types of tailings in China, siliceous tailings are mainly composed of Sio _ 2 and Al _ 2O _ 3, which are similar to pozzolanic materials and possess the potential properties of reacting with CaOH ~ (2 +) to form hydraulics. In order to activate the pozzolanic activity of siliceous tailings, this paper studies the activation of mechanical grinding, chemical activator on pozzolanic activity of siliceous tailings, and the application of activated tailings in tailings composite cement. The results of mechanical grinding show that the pozzolanic activity of tailings increases with the increase of specific surface area. The specific surface area of tailings is 233.20 m2 / kg, and the activity index of 28 days is only 53.89. When grinding to 5 min, the specific surface area of tailings reaches 495.10 m ~ 2 / kg ~ (2) kg ~ (28) d activity index is 65.65%, grinding time is 45 min, the specific surface area is 849.40 m ~ (2 / kg) 路kg, and the activity index of 28 days is 80.94 cm ~ (-1). When the ratio of tailings to fly ash is 1: 1, the specific surface area reaches 1169.80 m ~ 2 / kg ~ (-1) 路kg ~ (-1) and the compressive strength reaches to 50.25 MPA ~ (28) d. The activity index is 94.56, which is obviously higher than that of tailings' sole grinding activity. When the specific surface area is 1161.70m2/kg, the compressive strength is 37.61MPa / 28d and the activity index is 73.78. Cao and CaCl2 have a better early strength effect on siliceous tailings mixture. The suitable addition amount of Cao is 2. The specific surface area of the sample is 880.40m-2 / kg3d and the compressive strength is 22.25MPa/ 28d. The optimum content of CaCl2 is 1, the specific surface area is 903.90 m2 / kg, the compressive strength of 3 days is 22.14 MPA / 28d and the activity index is 81.74. Through the study of the application performance of activated tailings in tailing composite cement, it is found that the setting time of cement with tailings increases with the increase of specific surface area of tailings, and the water consumption of cement standard consistency in the system increases gradually. When the specific surface area of tailings reaches 840.30m2 / kg and the addition amount is 30cm, it can satisfy the requirements of P 鈪,
本文編號:2011599
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