( 中南大學(xué) 冶金科學(xué)與工程學(xué)院, 長(zhǎng)沙 410083)
摘 要: 針對(duì)我國(guó)鋁土礦資源特點(diǎn)和我國(guó)燒結(jié)法生產(chǎn)氧化鋁的現(xiàn)狀,論述了強(qiáng)化燒結(jié)法生產(chǎn)氧化鋁新工藝。 采用鋁硅比為9.62的礦石,按照鈣比為1.3~2.0, 堿比為1進(jìn)行配料, 在1250℃以上進(jìn)行熟料燒成。 實(shí)驗(yàn)結(jié)果顯示: 燒成的熟料溶出條件寬松,二次反應(yīng)程度弱; 溶出漿液在170℃左右直接進(jìn)行加壓脫硅,脫硅后溶液的硅量指數(shù)大于200, 再加入適量的石灰進(jìn)行深度脫硅,即使溶液中氧化鋁濃度超過200g/L時(shí),精液的硅量指數(shù)也大于600, 且得到的水化石榴石中二氧化硅飽和系數(shù)大于0.28; 通過加入晶種和采用新的碳酸化分解工藝制度,產(chǎn)品中的SiO2 含量降至0.025%, Na2O含量小于0.37%; 加入表面活性劑, 不僅能將碳分母液蒸發(fā)至Na2OT濃度大于300g/L, 而且還可有效減緩表面上結(jié)疤的形成速度。部分結(jié)果已應(yīng)用于工業(yè)實(shí)踐中, 單臺(tái)窯產(chǎn)能提高了19.7%, 工藝能耗降低了24.71%。
關(guān)鍵字: 強(qiáng)化燒結(jié)法; 氧化鋁生產(chǎn); 工藝; 應(yīng)用
for alumina production
PENG Zhi-hong, LIU Ye-xiang
( College of Metallurgical Science and Engineering,
Central South University, Changsha 410083, China)
Abstract: Based on the Chinese bauxite character and the status of the traditional sintering process, the intensified sintering process was studied. In the charge, the mass ratio of alumina to silica is 9.62, calcium ratio 1.3-2.0, alkali ratio 1.0, and then the charge is sintered above 1250℃. It is convenient for sinter to be leached, and the secondary reaction appears little. The slurry after sinter leaching is transferred into autoclave for desilicification at about 170℃, and the siliceous modulus of solution reaches more than 200. Then some lime is added for deep-desilication at normal pressure, the siliceous modulus of solution increases more than 600 even if the Al2O3 content is more than 200g/L.The SiO2 coefficient in hydrate garnet from deep-desilication is more than 0.28. Under conditions of the addition of seed and application of novel technology of carbonization, the contents of Na2O and SiO2 in product are less than 0.37% and 0.025%, respectively. When surfactant is added into spent liquor in the evaporation, the concentration of Na2OT can reach more than 300g/L, and the scale on the heating surface can be abated obviously. With the application of intensified sintering process the output of every rotary kiln increases by 19.7%, in the same time the energy consumption of alumina production decreases by 24.71%.
Key words: intensified sintering process; alumina production; technology; application


