本文選題：粗顆粒鋼渣 + 界面反應(yīng)��； 參考：《中國(guó)建筑材料科學(xué)研究總院》2015年碩士論文

【摘要】：本研究通過X射線衍射(XRD)、掃描電鏡(SEM)、水化熱等手段,探究了粗顆粒鋼渣在不同溫度下煅燒后自身形貌及礦物的變化、粗顆粒鋼渣與生料在高溫煅燒下的反應(yīng)機(jī)理以及外加不同摻量的粗顆粒鋼渣對(duì)水泥熟料礦物的影響。研究表明,粗顆粒鋼渣的摻入替代了部分水泥生料,降低了CO2的排放,同時(shí)碳酸鈣的分解溫度下降,有利于降低煅燒過程中能耗和氣體排放。隨著粗顆粒鋼渣的摻入,熟料煅燒低共熔溫度下降,促進(jìn)了燒成熟料礦物中游離氧化鈣的吸收,易燒性提高。經(jīng)高溫煅燒后,鋼渣自身的礦物含量及種類也發(fā)生一定變化,其內(nèi)部游離氧化物含量顯著減少,鋼渣中鐵鋁相膠凝礦物含量增加。RO相固溶體內(nèi)部固溶氧化物組成發(fā)生明顯變化,由以Fe O為主RO相轉(zhuǎn)變?yōu)橐訫g O為主RO相,溫度越高,轉(zhuǎn)化程度越大。通過對(duì)1350℃和1450℃下粗顆粒與生料界面的EMS形貌及XRD礦物相分析可得知,粗顆粒鋼渣與生料的過渡區(qū)在不同溫度均發(fā)生了化學(xué)反應(yīng),生成了以Fe、Al、Ca為主要元素的片狀或團(tuán)狀礦物,結(jié)合X射線衍射分析可判斷該過渡區(qū)域礦物為C4AF礦物,該過渡區(qū)反應(yīng)主要由生料提供鈣源,鋼渣提供Fe、Al相,隨著溫度的升高,鋼渣的反應(yīng)參與度增加。粗顆粒鋼渣的摻量低于20%時(shí),生成的鋼渣熟料易磨性較好。當(dāng)鋼渣摻量超過15%后,鋼渣易磨性下降較為明顯。鋼渣的摻入導(dǎo)致水化速率和放熱量均下降,早期強(qiáng)度呈現(xiàn)一定的下降,后期強(qiáng)度顯著增加,增長(zhǎng)率較快。在1450℃下煅燒后,摻15%粗顆粒鋼渣樣品28d水泥砂漿強(qiáng)度僅損失1.22Mpa,下降比例不超過3%。早期強(qiáng)度的下降主要是由于,鋼渣的摻入,帶入大量鐵相,降低了生料的鋁率,使熟料中C4AF含量上升,C3A含量下降。鋼渣的摻入,早期水化后,孔徑數(shù)量增多,隨著齡期的延長(zhǎng),有害孔逐漸被填充,這也是摻鋼渣熟料后期強(qiáng)度增長(zhǎng)迅速的重要因素。通過將上述研究成果應(yīng)用于湖南韶峰南方水泥有限公司日產(chǎn)2500噸的新型干法窯上,結(jié)果表明,粗顆粒鋼渣的摻入,降低了水泥熟料中C3S和C3A的含量,增加了C2S和C4AF含量,從而降低了水泥的水化放熱速率及放熱量,為生產(chǎn)低熱水泥和道路水泥提供了有利條件。同時(shí)C3S及C3A含量的上升,有利于提高水泥的抗硫酸鹽腐蝕性能。以10%粗顆粒鋼渣替代部分水泥生料能夠燒制出游離氧化鈣較低,強(qiáng)度較高,礦物分布均勻,結(jié)構(gòu)致密的優(yōu)質(zhì)硅酸鹽水泥熟料。
[Abstract]:By means of X-ray diffraction (XRD), scanning electron microscope (SEM), heat of hydration and so on, the morphology and mineral changes of coarse granular steel slag calcined at different temperatures were investigated. The reaction mechanism of coarse grain steel slag and raw meal under high temperature calcination and the effect of different amount of coarse grain steel slag on cement clinker mineral. The results show that the addition of coarse grain steel slag can replace some raw cement and reduce CO _ 2 emission, while the decomposition temperature of calcium carbonate is decreased, which is beneficial to reduce the energy consumption and gas emission during the calcination process. With the addition of coarse-grained steel slag, the low eutectic temperature of clinker calcination decreases, which promotes the absorption of free calcium oxide in clinker minerals and improves its burnability. After high temperature calcination, the mineral content and species of steel slag also changed to a certain extent, the content of free oxide in steel slag decreased significantly, and the content of iron and aluminum phase cementing mineral in steel slag increased. The composition of solid solution oxide in the solid solution of RO phase changed obviously. The higher the temperature is, the greater the transformation degree is when the RO phase is changed from Feo phase to MgO phase. The morphology and mineral phase of the interface between coarse grain and raw meal at 1350 鈩，

本文編號(hào)：1996252