本文關(guān)鍵詞：固硫灰的資源化利用研究　出處：《西南科技大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 固硫灰 資源化利用 鐵回收 改性吸附 磁性沸石

【摘要】：為了實(shí)現(xiàn)節(jié)能減排,我國正大力發(fā)展循環(huán)流化床技術(shù)。固硫灰是循環(huán)流化床鍋爐燃燒后從煙道收集的飛灰,每年的排放量很大。本論文擬通過研究來自四川內(nèi)江和貴州畢節(jié)固硫灰的基本物化性質(zhì),然后針對其特性,進(jìn)行有用組分的回收和利用,主要包括回收固硫灰中的鐵、改性固硫灰的制備以及利用固硫灰制備磁性分子篩等。研究發(fā)現(xiàn),固硫灰中的主要成分是Si O2、Al2O3、Fe2O3,其成分占70%~80%,以石英、硬石膏和赤鐵礦為主相,表面粗糙、疏松多孔。在固硫灰中回收鐵的研究中,焙燒溫度、時(shí)間、還原劑用量以及磁場強(qiáng)度的大小均對磁化焙燒-磁選過程有很大影響。添加5%的煤粉作為還原劑,于800℃下還原焙燒90min,在場強(qiáng)200KA/m下經(jīng)粗磁選,可獲得品位51.62%、回收率86.41%的粗鐵精礦,再經(jīng)80KA/m弱磁場強(qiáng)度下精選,鐵精礦品位可達(dá)58.02%,回收率為76.27%,XRD表明精礦主要礦相為磁鐵礦。固硫灰的改性研究表明,改性體系的固液比、改性劑濃度、反應(yīng)時(shí)間以及水浴溫度等工藝參數(shù)對吸附性能影響較大,其中當(dāng)利用質(zhì)量濃度為10%碳酸鈉,在80℃下改性2h的時(shí)候,SEM顯示顆粒表面形成更多孔洞,Zeta電位測試表明,改性灰負(fù)于原灰,與金屬陽離子存在的靜電引力更強(qiáng)。改性灰對重金屬Pb2+和Cu2+的吸附去除率達(dá)到95.94%和91.35,較原灰提高了20%以上。以固硫灰和Na OH為原料,不添加硅鋁源,可制得主相為方鈉石的磁性分子篩。體系堿度、晶化溫度和時(shí)間對沸石的結(jié)晶均存在影響,具體表現(xiàn)為堿度越高、晶化溫度越高、時(shí)間越長,越有利于方鈉石的結(jié)晶成型。當(dāng)堿度2.78mol/L,晶化溫度為125℃,晶化24h的條件時(shí),結(jié)晶度較高,這時(shí)對Pb2+的飽和交換吸附量為97.87mg/g,磁性能分析表明,合成的分子篩具有一定磁性,其飽和磁化強(qiáng)度Ms為2.00782emu/g,剩余磁化強(qiáng)度Mr為0.48emu/g,矯頑力Hc=138.2Oe,產(chǎn)物的磁分離效果明顯。
[Abstract]:In order to realize energy saving and emission reduction, circulating fluidized bed (CFB) technology is being developed in China. Sulfur fixation ash is the fly ash collected from flue after combustion in CFB boiler. The annual emissions are very large. This paper intends to study the basic physical and chemical properties of sulfur fixing ash from Neijiang and Bijie of Guizhou Province, and then carry out the recovery and utilization of useful components according to its characteristics. It mainly includes the recovery of iron from sulfur fixing ash, the preparation of modified sulfur fixing ash and the preparation of magnetic molecular sieve using sulfur fixing ash. It is found that the main component of sulfur fixing ash is Sio _ 2 / Al _ 2O _ 3 and Fe _ 2O _ 3. The main phase is quartz, anhydrite and hematite. The surface is rough and porous. In the study of iron recovery from sulfur fixing ash, the calcination temperature and time are obtained. The amount of reducing agent and the intensity of magnetic field have great influence on the process of magnetization roasting and magnetic separation. 5% coal powder was added as reducing agent and calcined at 800 鈩，

本文編號：1369364