煤气化灰渣的分选加工利用研究

发布时间：2018-06-12 22:58

本文选题：气化灰渣 + 理化特性　；参考：《西安科技大学》2017年硕士论文

【摘要】：本文以Texaco水煤浆加压气化炉产生的灰渣为主要研究对象,对比探讨了炉顶飞灰细渣与炉底熔融粗渣的生成条件,针对制浆原煤与气化粗、细渣的基本性质加以分析,包括样品粒度、密度组成与灰分分布、矿物质组分、有机官能团组成、扫描电子显微形貌以及孔径分布等分析试验。结果发现,粗、细渣固定碳含量较原煤有很大程度的减少,煤中具有规则晶型结构的矿物质出现点阵结构缺陷而逐渐形成非晶态玻璃体结构,与周围不同晶态、非晶态物质相互发生低温共融现象。相变生成其他新物质取代原有矿物,氧化反应使得有机质表面-COOH、-OH、-C=O等亲水官能团数量与种类增加,炭颗粒表面孔结构转为中微孔为主,数量急剧增加,比表面积值原煤为8.2821m2/g,粗渣183.4502m2/g,细渣 258.2878m2/g;平均孔径:原煤 9.4901nm,粗渣 5.0214nm,细渣6.1767nm。正浮选方法首先探索了原矿浆条件下柴油作捕收剂,起泡剂为仲辛醇的单因素条件试验,得到的浮精煤产品最优点为柴油5000g/t,仲辛醇4500g/t时,浮选完善指标仅0.74%。使用CaC12调节矿浆Zeta电位从-24.1mv升至-0.248mv后进行药剂制度探索试验,在减少药剂用量的前提下浮选完善指标同时得到提高,柴油4000g/t,仲辛醇3500g/t用量下浮选完善指标0.91%。同时加入矿浆超声波预处理步骤,超声频率40kHz,功率300W,先后探索了超声时长、捕收剂、起泡剂用量、矿浆浓度、充气量单因素试验,最终得到的最佳浮选条件为超声时间4min,柴油3500g/t,仲辛醇2500g/t,矿浆浓度60g/L,充气量0.3m3/h,得到精煤产率为7.15%,灰分55.36%,浮选完善指标2.01%。反浮选试验主要是将矿浆中无机矿物质作为浮选捕收的目标矿物进行分离。单因素条件试验包括炭的抑制剂选取β-CD和可溶性淀粉,捕收剂选取CTAB和DDA,起泡剂选用2号油和仲辛醇作对比试验以及矿浆pH调节,试验结果以反浮选效率作为评价指标。得到的最佳条件为:矿浆浓度60g/L,浮选机转速1900r/min,充气量0.3m3/h,抑制剂β-CD用量800g/t,捕收剂DDA盐溶液5500g/t,起泡剂2号油4000g/t,pH=8.3,此时得到的上浮精矿产率17.08%,灰分83.62%,浮尾产率82.92%,灰分55.27%,反浮选效率为15.69%。在单因素条件中选取β-CD、2号油、DDA盐溶液进行反浮选响应曲面三因素三水平优化试验,利用Minitab 15软件进行试验结果分析得到反浮选效率与三种药剂间作用的变化规律。三因素显著程度依次为:DDA盐溶液β-CD2号油。方程预测的最佳药剂条件为β-CD用量823.23g/t,DDA盐溶液5587.87g/t,2号油3945.46g/t,所得反浮选效率最大值16.30%。对该条件进行试验验证,得到实际反浮选效率为16.23%,误差0.07%。通过浮选的方法能够将气化灰渣中的未燃炭进行分选富集,实现有机可燃体-无机矿物质的有效分离,符合目前对于资源循环利用的要求。
[Abstract]:Taking the ash produced by Texaco coal water slurry pressurized gasifier as the main research object, the formation conditions of fly ash fine slag at the top of the furnace and the melting coarse slag at the bottom of the furnace are compared and discussed, and the basic properties of the raw coal and gasification coals and fine slag are analyzed. The sample size, density composition and ash distribution, mineral composition, organic functional group composition, scanning electron microscopy and pore size distribution were analyzed. The results show that the fixed carbon content of coarse and fine slag is much lower than that of raw coal, and the minerals with regular crystal structure appear lattice structure defects and form amorphous glass structure gradually, which is different from the surrounding crystalline structure. Low temperature co-melting occurs between amorphous materials. Other new substances were formed to replace the original minerals. The oxidation reaction increased the number and species of hydrophilic functional groups such as -COOH- OHH-CnO on the surface of organic matter, while the pore structure of carbon particles changed to mesoporous, and the number of them increased sharply. The specific surface area of raw coal is 8.2821 m2 / g, crude slag is 183.4502m2 / g, fine slag is 258.2878 m2 / g, average pore size is 9.4901nm, crude slag 5.0214nm, fine slag 6.1767nm. In this paper, the single factor experiment of diesel oil as collector and foaming agent as secondary octanol under the condition of raw pulp was first explored. The result shows that the most advantage of floating coal product is diesel oil 5000g / t, and the flotation consummation index is only 0.74g / t when secondary octanol 4500g/t. After using CaC12 to adjust the Zeta potential of pulp from -24.1mv to -0.248mv, the experiment of reagent system exploration was carried out. The flotation consummation index of diesel oil increased at the same time under the premise of reducing the dosage of reagent. The flotation consummation index of diesel oil 4000g / t, secondary octanol 3500g/t was 0.91g / t. At the same time, the ultrasonic pretreatment step of pulp was added, the ultrasonic frequency was 40kHz, the power was 300W. The single factor tests of ultrasonic duration, collector, amount of foaming agent, pulp concentration and aeration volume were explored successively. The optimum flotation conditions were obtained as follows: ultrasonic time 4 min, diesel 3 500 g / t, secondary octanol 2 500 g / t, pulp concentration 60 g / L, aeration volume 0.3 m3 / h, yield of clean coal 7.15%, ash 55.36 and flotation improvement index 2 01. The reverse flotation test is mainly to separate inorganic minerals from pulp as the target minerals for flotation collection. Single factor tests included 尾 -CD and soluble starch for carbon depressant, CTAB and DDAfor collector, No. 2 oil and secondary octanol for foaming agent and pH adjustment for pulp. The optimum conditions are as follows: pulp concentration 60 g / L, flotation machine rotation speed 1900 r / min, aeration volume 0.3 m 3 / h, depressant 尾 -CD dosage 800 g / t, collector DDA salt solution 5 500 g / t, foaming agent 2 oil 4 000 g / t, pH = 8.3%. At this time, the floatation concentrate yield is 17.08, ash content is 83.62, floating tail yield is 82.92, ash fraction is 55.27 and reverse flotation efficiency is 15.69. In the single factor condition, 尾 -CD-2 oil DDA salt solution was selected to carry out the three-factor and three-level optimization test of the reverse flotation response surface. The change law of the reverse flotation efficiency and the interaction between the three reagents was obtained by using Minitab15 software. The order of the three factors was 尾-CD _ 2 oil in the solution of DDA salt. The optimum reagent conditions predicted by the equation are as follows: the dosage of 尾 -CD is 823.23g / t DDA salt solution 5587.87g / t, the second oil 3945.46g / t, and the maximum reverse flotation efficiency 16.30g / t. The experimental results show that the actual reverse flotation efficiency is 16.23 and the error is 0.07. The unburned carbon in gasified ash can be separated and enriched by flotation, and the effective separation of organic combustibles and inorganic minerals can be realized.
【学位授予单位】：西安科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD94;TD923

【参考文献】