發(fā)布時間：2019-05-18 05:34

【摘要】：隨著細粒煤產(chǎn)量的提高,選煤廠浮選尾煤與日俱增,已經(jīng)成為最大的工業(yè)固體廢棄物之一。常規(guī)對浮選尾煤的處理利用多集中在混煤燃燒、型煤和建筑材料等方面,對尾煤中具有提純價值的礦物質(zhì)和微量元素的綜合利用較少。開發(fā)浮選尾煤高效利用技術(shù),實現(xiàn)浮選尾煤的高附加值利用,不僅能變廢為寶,節(jié)能減排,還可以提高企業(yè)經(jīng)濟效益。同時也為防止環(huán)境污染,緩解我國經(jīng)濟快速發(fā)展帶來的資源緊缺等問題具有促進作用,對我國經(jīng)濟、環(huán)境的可持續(xù)發(fā)展戰(zhàn)略具有重要意義。本文以浮選尾煤為研究對象,在分析原煤中礦物質(zhì)在浮選過程的遷移規(guī)律的基礎(chǔ)上,建立了礦物質(zhì)與灰分的一般數(shù)學(xué)關(guān)系;開展了以回收浮選尾煤中含量最高的高嶺石為目的的試驗研究,通過沉降和浮選的方法,對尾煤中高嶺石進行提純,確定最佳藥劑制度和實驗方案,并對浮選機理進行初步探索;在此基礎(chǔ)上,對提純后的高嶺石精礦進行鎵元素的分布和遷移規(guī)律研究,考察不同分級條件下鎵元素的遷移特征,并且考察了不同煅燒-酸浸條件下鎵的溶出特性,為浮選尾煤中礦物質(zhì)高嶺石和鎵元素的提純提供理論依據(jù)。結(jié)果如下:(1)原煤中礦物質(zhì)在浮選過程的遷移規(guī)律顯示,高嶺石的含量y與尾煤灰分x滿足二次函數(shù)y=-0.0053x2+0.9x+6.87關(guān)系,石英的含量與尾煤灰分x滿足一次函數(shù)y=0.32x-1.3752,方解石的含量與尾煤灰分無明確的數(shù)學(xué)關(guān)系。隨密度級增大,尾煤中礦物質(zhì)含量逐漸升高;隨粒度的增大,方解石含量逐漸升高,石英和高嶺石含量逐漸降低。(2)浮選尾煤中高嶺石的沉降和浮選提純試驗結(jié)果表明,沉降法提純高嶺石的回收率不超過35%;浮選法提純試驗中,捕收劑單獨作用下,CTAB對高嶺石的浮選回收率達到91.25%,精礦高嶺石品位由尾煤中35.72%提高至65.19%,在六種捕收劑中達到最高。通過金屬離子對陰離子捕收劑MAP-K的活化試驗可知,當(dāng)Fe3+用量為3×10-4mol/L時,精礦高嶺石的回收率由56.69%上升至83.86%。CTAB與MAP-K混合使用條件下,高嶺石的最高回收率為80%。捕收劑單獨作用下的捕收能力大小順序為:CTABDDAMAP-K油酸鈉辛烷基二甲基叔胺SDBS;不同浮選體系中,高嶺石浮選的回收率的效果為:CTAB(單獨作用)MAP-K(Fe3+配合使用)CTAB與MAP-K混合。(3)物料性質(zhì)及試驗條件對高嶺石浮選精礦中鎵的分布的影響試驗結(jié)果顯示,隨著樣品粒度級的降低、密度級的升高,鎵的含量不斷提高,-0.045mm樣品中鎵的含量達到30.59μg/g,+1.8kg/L密度級樣品中鎵的含量為30.03μg/g,均達到工業(yè)利用標(biāo)準;而且高嶺石品位與鎵的含量滿足線性遞增關(guān)系。對高嶺石精礦進行煅燒-酸浸結(jié)果顯示,在700oC下煅燒130min,并采用6mol/L的鹽酸作為浸出液,在60oC浸取溫度下鎵溶出率為91.86%,溶出效果最佳。
[Abstract]:With the increase of fine coal output, floatation tail coal in coal preparation plant is increasing day by day, and has become one of the largest industrial solid wastes. The conventional treatment and utilization of flotation tail coal is mainly focused on mixed coal combustion, briquette and building materials, but the comprehensive utilization of minerals and trace elements with purification value in tail coal is less. The development of high efficiency utilization technology of flotation tail coal and the realization of high added value utilization of flotation tail coal can not only turn waste into treasure, save energy and reduce emissions, but also improve the economic benefit of enterprises. At the same time, it also plays an important role in preventing environmental pollution and alleviating the shortage of resources caused by the rapid economic development of our country, which is of great significance to the sustainable development strategy of our economy and environment. In this paper, the flotation tail coal is taken as the research object, and the general mathematical relationship between minerals and ash is established on the basis of analyzing the migration law of minerals in raw coal in flotation process. An experimental study was carried out for the purpose of recovering the highest content of Kaolinite in the tail coal of flotation. The method of sedimentation and flotation was used to purify the kaolinite from the tailings coal, and the optimum reagent system and experimental scheme were determined. The flotation mechanism is also explored. On this basis, the distribution and migration of gallium elements in purified Kaolinite concentrate were studied, the migration characteristics of gallium elements under different classification conditions were investigated, and the dissolution characteristics of gallium under different calcination and acid leaching conditions were investigated. It provides a theoretical basis for the purification of kaolinite and gallium elements in flotation tail coal. The results are as follows: (1) the migration law of minerals in raw coal during flotation shows that the content y of kaolinite and the content x of tail coal ash satisfy the quadratic function y=-0.0053x2 0.9x 6.87. The content of quartz and the content of tail coal ash satisfy the first order function y 鈮，

本文編號：2479726