發(fā)布時間：2018-03-15 07:12

  本文選題：SiC-Si廢料　切入點：氧化　出處：《濟南大學》2017年碩士論文　論文類型：學位論文

【摘要】：太陽能光伏所需晶體硅片加工過程中產(chǎn)生大量的切割廢料漿。干燥后固態(tài)切割廢料除含少量聚乙二醇外,主要成分為SiC、Si,因此稱之為SiC-Si廢料。本課題首先研究了某晶體硅片廠排放的SiC-Si廢料的組成及其升溫氧化過程,在此基礎上采用燒結(jié)法直接制備了硅質(zhì)耐火材料,并通過調(diào)整廢料中Al2O3的摻量制備了性能優(yōu)良的多孔和莫來石質(zhì)耐火材料。利用這種固體廢棄物制備耐火材料有助于減輕企業(yè)的環(huán)保壓力,并降低耐火材料的生產(chǎn)成本。實驗通過XRF、XRD、TG、SEM等現(xiàn)代測試手段對SiC-Si廢料原粉和氧化料、制備的耐火材料進行了分析,探討了不同溫度、升溫速率和粒度對廢料氧化性的影響以及制備工藝對耐火材料形成、結(jié)構(gòu)和性能的影響。通過大量實驗,確定了該廢料制備硅質(zhì)、多孔和莫來石質(zhì)耐火材料的最佳配比及工藝參數(shù)。成分分析顯示所用SiC-Si廢料中含有62.63%SiC和27.49%Si,這些成分可作為制備耐火材料的硅源。結(jié)合20-1500℃范圍內(nèi)的非恒溫和恒溫熱重分析以及X射線衍射分析結(jié)果,可以看出SiC-Si廢料的升溫氧化過程包含Si的氧化、Fe的氧化和SiC的氧化三個階段,完全氧化后的產(chǎn)物是方石英和Fe2O3。球磨預處理和以較低的升溫速率升溫更有利于SiC-Si廢料的氧化。單獨以SiC-Si廢料為原料采用燒結(jié)法成功制備了以方石英為主晶相的硅質(zhì)耐火材料。最佳制備工藝條件為:在50MPa壓力下制坯,以3℃/min的升溫速率升溫到1550℃,燒結(jié)6h。所得試樣中SiO2含量為94.86%,體積密度為1.75g/cm3,抗折強度為23.32MPa,耐火度可達1680℃。SiC-Si廢料中的SiC高溫氧化會產(chǎn)生SiO2和碳氧化物氣體,Fe會被氧化成Fe2O3,通過調(diào)整配料中Al2O3的摻量,可在高溫熱燒結(jié)時形成液相,同時碳氧化物氣體被這種液相包裹難以排出,從而成功的制備了多孔耐火材料。研究表明,當Al2O3摻量為20%時,SiC-Si廢料在1515℃燒結(jié)2h可制備出多孔耐火材料。燒結(jié)所得試樣體積密度為0.78g/cm3,室溫導熱系數(shù)為0.354W/(mK),耐火度可達1560℃,可作為高溫隔熱保溫材料使用。SiC-Si廢料的氧化產(chǎn)物以SiO2為主,為獲得莫來石相含量較高的耐火材料,需在原料中加入67~80%的Al2O3。實驗比較了氧化鋁摻量、燒結(jié)溫度、燒結(jié)時間對燒結(jié)體中莫來石生成的影響。結(jié)果表明,當氧化鋁摻量為75%,燒結(jié)溫度為1550℃,燒結(jié)時間為2h時,熱處理后的試樣莫來石相含量最高,可達92.99%。試樣的體積密度為1.63g/cm3,耐火度超過1800℃。
[Abstract]:A large amount of cutting waste slurry is produced during the processing of crystal silicon wafer required for solar photovoltaic. The solid cut waste after drying contains a small amount of polyethylene glycol. The main component is sic Si, so it is called SiC-Si waste. Firstly, the composition of SiC-Si waste discharged from a crystal silicon wafer plant and its heating and oxidation process are studied. On this basis, silicon refractories are directly prepared by sintering method. The porous and mullite refractories with excellent properties were prepared by adjusting the amount of Al2O3 in the waste materials. In addition, the production cost of refractories was reduced. The raw powder and oxidizing material of SiC-Si waste were analyzed by means of modern testing methods such as XRF, XRD, TG-SEM, and the different temperatures were discussed. The effects of heating rate and particle size on the oxidation of the waste and the effect of the preparation process on the formation, structure and properties of the refractory. Optimum proportioning and technological parameters of porous and mullite refractories. Composition analysis shows that the waste SiC-Si used contains 62.63sic and 27.49Si. these components can be used as silicon source for the preparation of refractories. Combined with non-constant temperature and constant temperature in the range of 20-1500 鈩，

本文編號：1614964