无机盐—表面活性剂对氧化煤泥浮选促进机理的研究

发布时间：2018-03-28 14:12

  本文选题：氧化煤　切入点：浮选　出处：《太原理工大学》2017年硕士论文

【摘要】：随着采煤机械化强度的提高和煤层的变化,煤泥由于氧化生成亲水性的含氧官能团,易与水分子形成氢键而变的越来越难浮选。近年来,很多学者对煤泥的浮选药剂进行了研究,发现某些表面活性剂不仅能够增加煤泥表面的疏水性,还能对捕收剂产生乳化作用,促进煤泥表面捕收剂的吸附,增强了捕收剂的捕收性,从而提高浮选效率和精煤产量。本项目的浮选煤泥是用双氧水在室温下氧化的屯兰精煤。煤泥氧化前后浮选试验的可燃体回收率降低13.63%,说明该煤泥被氧化后疏水性变差。红外光谱显示氧化后煤泥波数在3300cm-1~3650cm-1的-OH、-COOH吸收峰面积明显增大;3010cm-1~3040cm-1的C=C吸收峰和3000cm-1~3100cm-1苯C-H吸收峰面积减小;氧化后煤泥在1684 cm-1~1724cm-1附近出现C=O的吸收峰。煤泥氧化前的润湿热是0.234J.g-1,氧化后的润湿热是0.657J.g-1,表明氧化煤更亲水,不利于浮选。选取三种不同类型的表面活性剂,阳离子型(CTAB和DTAC),阴离子型(SDS和SDBS)和非离子型(FM、TWEEN20、TWEEN80、OP-4、OP-13、PEG400DO、ODEA和SPAN80),对屯兰人工氧化煤泥进行浮选试验研究,并利用红外光谱和润湿热进行机理分析。试验结果表明:阴离子型的SDBS效果最好,当SDBS的用量为300g/t时,可燃体回收率提高了14.56%,精煤产率提高了14.61%,精煤灰分9.13%,尾煤灰分31.53%;当SDS的用量为300g/t时,可燃体回收率提高了12.99%,精煤灰分9.19%,尾煤灰分26.67%,它们可以提高精煤产率和尾煤灰分,对氧化煤的选择性好,提升了浮选效率。阳离子型的CTAB和DTAC促进作用明显,仅次于阴离子型。非离子型表面活性剂有促进作用,但OP-4的用量为350g/t时,可燃体回收率降低了38.16%,精煤灰分7.67%,尾煤灰分11.23%,对氧化煤的浮选具有抑制作用。SDBS,SDS,CTAB和DTAC吸附于煤泥表面,烷烃链增加了煤泥表面的疏水性。非离子型的表面活性剂(FM、SPAN80、ODEA)有乳化作用,促使煤油在溶液中分散成小液滴,增强了煤油的分散性和捕收性,提高了浮选效果。润湿热表明三种表面活性剂的促进效果为阴离子型阳离子型非离子型。然后在氧化煤泥浮选过程中添加Mg SO_4、FeCl_3和Ca Cl_2,研究无机阳离子对氧化煤泥浮选的影响。结果表明:当Mg SO_4的用量为500g/t时,可燃体回收率提高了8.37%;当Ca Cl_2的用量为250g/t时,可燃体回收率提高了3.89%;当FeCl_3的用量为50g/t时,可燃体回收率提高了4.60%。因此,这三种离子的促进效果为Mg~(2+)Fe~(3+)Ca~(2+)。添加Mg~(2+)后,润湿热降低了0.114 J.g-1;添加Fe~(3+)后润湿热降低了0.09 J.g-1;添加Ca~(2+)后润湿热降低了0.028 J.g-1,润湿热表明这三种无机阳离子都能降低氧化煤的亲水性,且它们对氧化煤疏水性的影响为Mg~(2+)Fe~(3+)Ca~(2+)。最后在氧化煤泥浮选过程中同时添加无机阳离子和表面活性剂,研究无机盐-表面活性剂对氧化煤泥浮选的共同促进作用。结果表明:在添加Mg SO_4,Ca Cl_2和FeCl_3这三种无机盐时,SDBS和SDS这两种阴离子型表面活性剂的浮选效率降低;PEG400DO,TWEEN80这两种非离子型表面活性剂有促进作用,OP-4对氧化煤的抑制作用更强。红外光谱显示,在添加硫酸镁后,SDBS和SDS两种药剂的含氧官能团增加,疏水性降低;PEG400DO和TWEEN80两种药剂的含氧官能团减少,疏水性增强;OP-4的含氧官能团增多,亲水性增强。SDBS和SDS的润湿热增大,PEG400DO和TWEEN80的润湿热减小,OP-4的润湿热增大,与浮选试验一致。
[Abstract]:With the change of mining mechanization strength and coal slime, because oxygen containing groups generate hydrophilic oxide, and water molecules form hydrogen bonds and become more and more difficult to flotation. In recent years, many scholars of the slime flotation agent was studied, found that some surfactants can not only increase the hydrophobicity of the surface of coal slime the collector can produce emulsification, promote collector adsorption surface enhanced slime collector collector collector, so as to improve the flotation efficiency and yield of cleaned coal. Coal slurry flotation of this project is to use hydrogen peroxide oxidation at room temperature in Tunlan coal. The combustible recovery of the flotation test of 13.63% reduction rate the coal slime before and after oxidation, oxidation after hydrophobic variation. The infrared spectra showed that the oxidation of coal in the 3300cm-1~3650cm-1 -OH -COOH wave, the absorption peak area increased significantly; 3010cm-1~3040cm-1 C =C absorption C-H peak and 3000cm-1~3100cm-1 benzene absorption area decreased; oxidized coal slime absorption peak appears at about 1684 cm-1~1724cm-1 C=O. The slime oxidation of the wetting heat is 0.234J.g-1, oxidation after wetting heat is 0.657J.g-1, that the oxidation of coal is more hydrophilic, is not conducive to the flotation. Selecting three different types of surface active agent, cationic (CTAB and DTAC (SDS), anionic and nonionic (SDBS) and FM, TWEEN20, TWEEN80, OP-4, OP-13, PEG400DO, ODEA and SPAN80), experiments were carried out on Flotation of oxidized coal slime and artificial Tunlan, was analyzed by infrared spectroscopy and wetting heat. The experimental results show that the best type of anion the effect of SDBS, when the dosage of SDBS was 300g/t, the combustible recovery increased by 14.56%, coal yield increased by 14.61%, 9.13% of coal ash, coal 31.53%; when the dosage of SDS was 300g/t, the combustible recovery increased by 12.99%, coal ash In 9.19%, coal 26.67%, they can improve the yield of clean coal and coal, the selective oxidation of coal, improve the flotation efficiency. Obvious effect of cationic CTAB and anionic DTAC. After the promotion, nonionic surfactants have stimulative effect, but the amount of OP-4 was 350g/t, the combustible the recovery rate is reduced by 38.16%, 7.67% of coal ash, coal 11.23%, coal flotation on the oxidation inhibited.SDBS, SDS, CTAB and DTAC adsorption on coal surface, the hydrophobic alkyl chain increased coal surface. Non ionic surfactant (FM, SPAN80, ODEA) with emulsification, prompting kerosene in solution dispersed into small droplets, enhance the dispersion and collecting of kerosene, improve the flotation effect. The wetting heat showed that three kinds of surfactant effect for anionic cationic nonionic. Then the oxidized coal slime flotation. 绋嬩腑娣诲姞Mg SO_4,FeCl_3鍜孋a Cl_2,鐮旂┒鏃犳満闃崇�诲瓙瀵规哀鍖栫叅娉ユ诞椋�

本文编号：1676659