本文選題：貧紅土鎳礦　切入點(diǎn)：焙燒-磁選　出處：《西安建筑科技大學(xué)》2017年碩士論文

【摘要】：隨著全球?qū)︽囆枨罅康脑黾右约傲蚧嚨V的日益枯竭,紅土鎳礦的開(kāi)發(fā)利用研究工作逐漸成為熱點(diǎn)。傳統(tǒng)的焙燒-磁選工藝及化學(xué)浸出工藝不僅對(duì)不同類型紅土鎳礦適應(yīng)性較差,還存在著有用組分綜合利用率低及產(chǎn)品附加值低等問(wèn)題。鑒于此,研究以青海某紅土鎳礦為原料,采用正交試驗(yàn)方法進(jìn)行了焙燒-磁選及化學(xué)浸出工藝對(duì)比,并闡明了不同因素對(duì)選別效果的影響規(guī)律。研究還對(duì)酸浸貴液中的鎳離子等的綜合回收進(jìn)行了探索試驗(yàn)。在此基礎(chǔ)上,取得了以下成果:紅土鎳礦的焙燒-磁選正交試驗(yàn)結(jié)果表明,對(duì)焙燒-磁選鎳粗精礦的產(chǎn)率和回收率影響的因素顯著性依次為磁場(chǎng)強(qiáng)度物料厚度還原時(shí)間還原溫度還原劑用量。焙燒-磁選鎳的優(yōu)化條件為:還原劑用量為5%、還原溫度為800℃、料層厚度為10mm、還原時(shí)間為30min、磁場(chǎng)強(qiáng)度為2500A/m。在此條件下可獲得產(chǎn)率為22.88%和回收率為38.99%的鎳粗精礦。紅土鎳礦的浸出正交試驗(yàn)結(jié)果表明,影響鎳浸出率的因素顯著性依次為液固比浸出溫度硫酸濃度浸出時(shí)間攪拌速率,且浸出時(shí)間和攪拌速率,浸出時(shí)間和浸出溫度交互影響均不顯著。酸浸紅土鎳礦的最佳條件為:液固比為4:1,浸出溫度為100℃,硫酸濃度為5.2mol/L,浸出時(shí)間2.5h,攪拌速率為250r/min,在此條件下鎳的浸出率可達(dá)98.23%。此外,影響氧化鎂浸出率的最顯著因素為液固比和浸出溫度,浸出時(shí)間為一般顯著影響因素,而硫酸濃度和攪拌速率為不顯著影響因素。氧化鎂的浸出優(yōu)化條件為:液固比為3.5:1,浸出溫度為100℃,硫酸濃度為4.3mol/L,浸出時(shí)間4h,攪拌速率為250r/min,在此條件下氧化鎂的浸出率可達(dá)93.92%。浸出貴液中不同離子的綜合回收試驗(yàn)結(jié)果表明,分批加入117g氫氧化鈉,反應(yīng)時(shí)間為25min,控制礦漿pH值在5~6范圍內(nèi),可獲得鎳鐵混合沉淀產(chǎn)品。該產(chǎn)品在1320℃的條件下煅燒2h,經(jīng)磁選后可獲得鎳的品位為1.69%,回收率為82.04%。濾液經(jīng)靜置析晶及硫化除鎳凈化處理后,在溫度為150℃,攪拌速率為350 r/min,硫酸鎂與氫氧化鈉的摩爾比為1:2.5,硫酸鎂質(zhì)量濃度為3.5%,晶種添加量為硫酸鎂的3%,反應(yīng)時(shí)間為3h的條件下,采用水熱合成法可以獲得結(jié)晶良好的堿式硫酸鎂晶須。研究既可為紅土鎳礦的工業(yè)化生產(chǎn)提供理論依據(jù),也對(duì)同類礦石的現(xiàn)場(chǎng)生產(chǎn)有一定的指導(dǎo)意義。
[Abstract]:With the increase of global demand for nickel and the depletion of nickel sulphide ore, the development and utilization of laterite nickel ore has gradually become a hot spot.The traditional roasting magnetic separation process and chemical leaching process not only have poor adaptability to different types of laterite nickel ores but also have some problems such as low comprehensive utilization ratio of useful components and low added value of products.In view of this, the roasting, magnetic separation and chemical leaching processes of a laterite nickel ore in Qinghai Province were studied by orthogonal test, and the influence of different factors on the separation effect was clarified.The comprehensive recovery of nickel ions from acid leachate was also studied.On this basis, the following results have been obtained: the roasting and magnetic separation orthogonal test results of laterite nickel ore show that,The factors that influence the yield and recovery of roasting magnetic separation nickel concentrate are in turn the reduction time of reduction time of magnetic field strength material thickness and the amount of reducing temperature reductant.The optimum conditions for roasting and magnetic separation of nickel are as follows: reducing agent dosage is 5, reduction temperature is 800 鈩，

本文編號(hào)：1730660