本文選題：含釩石煤 + 浮選精礦��； 參考：《武漢工程大學(xué)》2016年碩士論文

【摘要】：高鈣鎂云母型含釩石煤占我國(guó)含釩石煤總量的30%以上,該類型礦石CaO+MgO含量15%以上。由于礦石中鈣鎂礦物含量高,采用傳統(tǒng)提釩工藝,會(huì)大幅增加浸出過(guò)程中酸堿消耗量,生產(chǎn)成本相應(yīng)增加,且過(guò)高的酸耗會(huì)嚴(yán)重污染環(huán)境。開(kāi)發(fā)綠色、高效的提釩工藝,是有效利用高鈣鎂云母型含釩資源亟需解決的難題。本研究在國(guó)家“十二五”科技支撐計(jì)劃項(xiàng)目資助下,以湖北某地高鈣鎂云母型含釩石煤為研究對(duì)象,基于“浮選—浸出”選冶聯(lián)合工藝,圍繞浮選精礦酸浸過(guò)程機(jī)理,開(kāi)展相關(guān)研究,獲得的主要結(jié)論如下:1.(含釩)云母礦物酸浸行為研究白云母浸出條件試驗(yàn)表明:增大硫酸濃度、浸出時(shí)間以及浸出溫度均能提高白云母中Al、K和Si的浸出率,但硫酸對(duì)白云母晶體結(jié)構(gòu)的破壞能力有限,Al、K和Si浸出率偏低;添加含氟助浸劑可顯著促進(jìn)白云母中Al、K和Si的浸出。對(duì)白云母浸出渣分別進(jìn)行FTIR、XRD和SEM分析,結(jié)果表明氫氟酸存在下,白云母在浸出過(guò)程結(jié)構(gòu)發(fā)生變化,八面體和四面體結(jié)構(gòu)發(fā)生相應(yīng)調(diào)整、變形,從而使Al、K和Si賦存的化學(xué)環(huán)境發(fā)生變化,浸出活性增強(qiáng)。含釩石煤礦石中,釩主要賦存于云母礦物晶格中,稱為含釩云母。白云母的浸出行為,間接揭示了含釩云母中釩的浸出行為。含氟助浸劑可促進(jìn)含釩云母中釩的浸出。2.云母型含釩石煤浮選精礦浸出試驗(yàn)高鈣鎂云母型含釩石煤經(jīng)浮選后的精礦,釩存在于云母礦物、電氣石類礦物以及鐵質(zhì)礦物,其中電氣石類礦物中含釩占10%左右,屬于難浸礦石。對(duì)浮選精礦采用硫酸直接浸出,在一定范圍內(nèi)增加硫酸濃度、升高溫度、延長(zhǎng)浸出時(shí)間以及增加液固比均有利于釩的浸出,但浸出率較低。添加含氟助浸劑對(duì)提高石煤中釩的浸出率效果明顯,尤其是氟硅酸鈉,且釩浸出率隨著含氟助浸劑用量的增加而提高,硫酸濃度為30%,氟硅酸鈉用量為16%,液固比為4:1mL/g,浸出溫度為90℃,浸出時(shí)間為12h,攪拌速度為600r/min,可得到86.18%的高浸出率;此外,在氟硅酸鈉存下,添加硝酸、氯酸鉀等氧化劑時(shí),釩浸出率提高程度較大,硝酸效果最佳提高了近7%。3.云母型含釩石煤浮選精礦酸浸機(jī)理石煤浮選精礦浸出渣XRD和SEM分析表明,硫酸浸出對(duì)石煤浮選精礦主要是對(duì)碳酸鹽的溶解作用,對(duì)石煤精礦中含釩礦物主體結(jié)構(gòu)破壞較小,含氟助浸劑作用下,含釩礦物晶體結(jié)構(gòu)被破壞,顆粒相互粘結(jié),層狀結(jié)構(gòu)發(fā)生崩塌,包裹在晶格中的釩被釋放出來(lái);氧化劑在一定程度上能定量的將難溶低氧化態(tài)釩氧化成為易溶高氧化態(tài)釩,從而提高石煤中釩的浸出率。
[Abstract]:The high - calcium - magnesium mica - type vanadium - containing stone coal accounts for more than 30 % of the total amount of vanadium - containing stone coal in China , and the content of CaO + MgO in the ores is over 15 % . Due to the high content of calcium and magnesium minerals in the ore , the acid and alkali consumption in the leaching process is greatly increased due to the high content of calcium and magnesium minerals in the ore . The experimental results show that the leaching rate of the vanadium in the mica is improved by increasing the concentration of sulfuric acid , leaching time and leaching temperature . The leaching behavior of the vanadium in the mica is obviously improved by adding the fluorine - containing leaching aid . The leaching rate of the vanadium is increased with the increase of the amount of the fluorine - containing leaching aid . The leaching activity is improved . The leaching temperature is 90 鈩，

本文編號(hào)：1864484