本文選題：水化硅酸鈣 + 托貝莫來石��； 參考：《中北大學》2017年碩士論文

【摘要】：粉煤灰是燃煤電廠排放出的固體廢棄物,不僅占用大量土地,而且污染環(huán)境。粉煤灰制備免燒磚可以提高粉煤灰的利用率,避免了大量使用粘土、煤等不可再生資源,同時,利用粉煤灰制備成免燒磚可以使煤基固廢得到循環(huán)利用。粉煤灰免燒磚在北方寒冷地區(qū)經(jīng)過凍融循環(huán)后容易出現(xiàn)開裂、強度降低等現(xiàn)象。僅僅通過改變原料配比并不能有效解決粉煤灰免燒磚抗凍性問題,研究發(fā)現(xiàn)養(yǎng)護制度對粉煤灰免燒磚抗凍性有很大影響,而反應(yīng)溫度和時間是影響?zhàn)B養(yǎng)護制度的兩個最重要因素。為了優(yōu)化蒸壓粉煤灰免燒磚的性能并制備出抗凍性較好的粉煤灰免燒磚,本文通過研究粉煤灰與生石灰在不同蒸壓溫度(120℃、140℃、160℃、180℃、200℃)和時間(4h、6h、8h、10h)下水化產(chǎn)物礦物組成和形貌來闡述粉煤灰在蒸壓下的水化機理。為了在較短反應(yīng)時間內(nèi)制備出滿足抗凍性要求的粉煤灰免燒磚,在粉煤灰水化機理的基礎(chǔ)上,設(shè)計了不同的養(yǎng)護制度,通過抗凍性試驗得出了最優(yōu)的養(yǎng)護制度,結(jié)論如下:(1)蒸壓溫度≤140℃時,即使反應(yīng)時間延長到10h也不會生成大量結(jié)晶度較好的托貝莫來石,當蒸壓溫度≥160℃時,160℃下,反應(yīng)10h時含鋁托貝莫來石含量達到最大,180℃下,反應(yīng)6h時含鋁托貝莫來石的含量達到最大,200℃下,反應(yīng)6h時含鋁托貝莫來石的含量達到最大。(2)通過X射線衍射K值法分析得出:反應(yīng)溫度≤140℃時,反應(yīng)10h內(nèi),隨著反應(yīng)時間延長,水化石榴石含量逐漸增加;反應(yīng)溫度≥160℃時,隨著反應(yīng)時間延長水化石榴石含量基本不發(fā)變化。(3)反應(yīng)溫度≤140℃時,產(chǎn)物的形貌以卷箔狀居多,此外也有少量團絮狀、顆粒狀、板狀水化產(chǎn)物,延長反應(yīng)時間水化產(chǎn)物搭接越來越致密。反應(yīng)溫度≥160℃時,160℃反應(yīng)6h出現(xiàn)“魚鱗”片狀水化產(chǎn)物;180℃反應(yīng)10h出現(xiàn)大量葉片狀水化產(chǎn)物;溫度為200℃時有纖維狀水化產(chǎn)物生成。(4)粉煤灰免燒磚在200℃下養(yǎng)護3h,然后在180℃下養(yǎng)護3h,經(jīng)過該養(yǎng)護制度后的粉煤灰免燒磚抗凍性比較優(yōu)異,滿足制品的抗凍性要求。
[Abstract]:Fly ash is a solid waste discharged from coal-fired power plants, which not only occupies a lot of land, but also pollutes the environment. The utilization ratio of fly ash can be improved by using fly ash to prepare no-fired brick, and a large number of non-renewable resources such as clay and coal can be avoided. At the same time, coal-based solid waste can be recycled by using fly ash to prepare no-fired brick. Fly ash brick is prone to crack and decrease in strength after freeze-thaw circulation in the cold area of northern China. Only by changing the ratio of raw material can not effectively solve the problem of freezing resistance of fly ash free fired brick. The research found that the curing system has a great influence on the freezing resistance of fly ash free fired brick. The reaction temperature and time are the two most important factors affecting the maintenance system. In order to optimize the properties of autoclaved fly ash unfired brick and prepare fly ash brick with good frost resistance, In this paper, the hydration mechanism of fly ash and quicklime under autoclaved pressure was studied by studying the mineral composition and morphology of hydration products of fly ash and quicklime at different autoclaved temperatures (120 鈩，

本文編號：1942137