拜耳法生產(chǎn)氧化鋁中脫鋅的研究
本文選題:鋁酸鈉溶液除鋅 + 硫化鈉; 參考:《昆明理工大學》2017年碩士論文
【摘要】:氧化鋁的純度是影響原鋁質(zhì)量的主要因素,同時也影響電解過程的技術(shù)經(jīng)濟指標。鋅是比鋁更正電性元素,會在電解過程中優(yōu)先鋁在陰極析出而使鋁錠的質(zhì)量降低。論文針對云南鋁土礦含鋅較高,生產(chǎn)中常出現(xiàn)鋅含量偏高的現(xiàn)象,對拜耳法生產(chǎn)氧化鋁中鋅的脫除進行了研究。在查閱和總結(jié)國內(nèi)外相關(guān)文獻資料的基礎(chǔ)上,對硫化物脫鋅過程進行了深入分析。利用E-pH圖探究了 S、Zn元素在堿性溶液中的行為;通過熱力學計算,分析了 pH值對硫化鈉脫鋅的影響,確定了適合拜耳液脫鋅的工藝環(huán)節(jié);研究了硫化鈉、二硫代氨基甲酸鹽和高硫鋁土礦三種脫鋅方法。實驗研究表明:利用用硫化鈉—絮凝法脫鋅時,Na2S用量0.5 g/L、反應(yīng)時間120 min、反應(yīng)溫度60℃、絮凝劑添加量0.1%的條件下,可將鋁酸鈉溶液中鋅雜質(zhì)從70mg/L降至10mg/L;添加硫化鈉的同時添加ZnS晶種,可以提高脫鋅效率,減少S2-引入,最佳條件為反應(yīng)溫度60℃,反應(yīng)時間90min,Na2S用量0.4g/L,ZnS晶種用量40mg/L,可將鋁酸鈉溶液中鋅雜質(zhì)從70mg/L降低到15mg/L以下;在沉降過程中添加硫化鈉脫鋅,僅用0.5g/L濃度Na2S,就可將鋁酸鈉溶液中的鋅雜質(zhì)從70mg/L降低到7mg/L,脫鋅效果明顯。利用二硫代氨基甲酸鹽法脫鋅時,在二甲基二硫代氨基甲酸鈉0.8g/L、反應(yīng)時間120min、反應(yīng)溫度80℃、絮凝劑添加量0.1%的條件下,鋁酸鈉溶液中鋅雜質(zhì)可降至15mg/L以下。在溶出過程添加高硫鋁土礦,添加比例為10%~20%時,也能達到較好的脫鋅效果,溶出液中的鋅雜質(zhì)從30mg/L降至15mg/L以下,符合生產(chǎn)要求。
[Abstract]:The purity of alumina is the main factor affecting the quality of the original aluminum, and it also affects the technical and economic indicators of the electrolytic process. Zinc is a more positive element than aluminum, and the quality of the aluminum ingot is reduced by the precipitation of the first aluminum in the electrolysis process. The paper has a high zinc content in Yunnan bauxite, and the phenomenon of high zinc content often appears in the production. The removal of zinc from alumina by ear method was studied. On the basis of consulting and summarizing the relevant documents at home and abroad, the process of zinc dezincing was deeply analyzed. The behavior of S and Zn in alkaline solution was explored by using E-pH diagram. The effect of pH value on dezincing of sodium sulfide was analyzed by thermodynamic calculation, and the suitability for the dezincing of sodium sulfide was determined. Three dezinnation methods of sodium sulfide, two thiocarbamate and high sulphur bauxite are studied in the process of dezinking of Bayer liquid. The experimental study shows that the dosage of Na2S is 0.5 g/L, the reaction time is 120 min, the reaction temperature is 60, and the adding amount of flocculant is 0.1%, and the zinc impurities in sodium aluminate solution can be from 70 under the condition of sodium sulfide flocculation. Mg/L is reduced to 10mg/L, and the addition of ZnS crystal with sodium sulfide can increase the dezine efficiency and reduce the introduction of S2-. The optimum condition is 60 C, 90min, Na2S dosage 0.4g/L, ZnS seed dosage 40mg/L, and the zinc impurities in sodium aluminate solution can be reduced from 70mg/L to 15mg/L below. In the process of sedimentation, the addition of sodium sulfide is only 0. The concentration of.5g/L in Na2S can reduce the zinc impurities in sodium aluminate solution from 70mg/L to 7mg/L, and the dezinnation effect is obvious. With two thiocarbamate dezinnation, the zinc impurities in sodium aluminate solution can be reduced to 15mg/L under the conditions of two methyl two sodium thiocarbamate 0.8g/L, reaction time 120min, reaction temperature 80, and 0.1% flocculant. The addition of high sulphur bauxite in the dissolution process can achieve better dezinion effect when the proportion is 10% to 20%, and the zinc impurity in the solution is reduced to less than 15mg/L from 30mg/L, which is in line with the production requirements.
【學位授予單位】:昆明理工大學
【學位級別】:碩士
【學位授予年份】:2017
【分類號】:TQ133.1
【參考文獻】
相關(guān)期刊論文 前10條
1 楊卉們;張亮;馮安生;譚秀民;;全球鋁土礦資源概況及供需分析[J];礦產(chǎn)保護與利用;2016年06期
2 姬天哲;;分析鋁土礦的不同加工法[J];現(xiàn)代國企研究;2016年10期
3 楊彪;;兩種不同類型鋁土礦原礦性質(zhì)及洗礦工藝的對比分析[J];采礦技術(shù);2016年01期
4 嚴良;楊敬一;徐心茹;;有機硅改性破乳-絮凝劑在含油污水處理中的應(yīng)用[J];化工環(huán)保;2015年06期
5 孫壁姍;;淺談鋁土礦資源的合理開發(fā)和利用[J];西部資源;2015年05期
6 高蘭;王登紅;熊曉云;齊帥軍;易承偉;夾少輝;;中國鋁土礦資源特征及潛力分析[J];中國地質(zhì);2015年04期
7 何厚華;朱挺健;劉澤;陳曼;王檑;;二甲基二硫代氨基甲酸鈉處理鋅冶煉含鎘廢水[J];化工環(huán)保;2015年03期
8 張秀;高萌;張信偉;楊志敏;陳玉成;;DTC類重金屬捕集劑對豬場廢水中Cu、Zn的去除試驗研究[J];農(nóng)業(yè)資源與環(huán)境學報;2015年03期
9 常青;;絮凝動力學的現(xiàn)狀與研究方法進展[J];環(huán)境科學學報;2015年10期
10 孫林賢;;我國氧化鋁工業(yè)現(xiàn)狀及發(fā)展策略[J];輕金屬;2015年01期
相關(guān)會議論文 前1條
1 汪德偉;王齊華;;黃鐵礦FeS_2晶體的制備研究進展[A];甘肅省化學會二十六屆年會暨第八屆中學化學教學經(jīng)驗交流會論文集[C];2009年
相關(guān)博士學位論文 前1條
1 俞小花;復雜銅、鉛、鋅、銀多金屬硫化精礦綜合回收利用研究[D];昆明理工大學;2008年
相關(guān)碩士學位論文 前4條
1 韓一杰;鎵在鋁土礦中賦存形態(tài)的分子模擬[D];太原理工大學;2016年
2 劉艷艷;高硫高有機物鋁土礦預處理及赤泥中鐵回收技術(shù)研究[D];北京化工大學;2014年
3 甄豪波;重金屬捕集劑DTC(TBA)的制備及處理含銅廢水的研究[D];華南理工大學;2011年
4 孫秀萍;DTC類重金屬離子捕集劑的合成、性能、表征[D];重慶大學;2007年
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