溶液性质及能量输入对煤泥及伴生矿物电动电位影响研究

发布时间：2018-02-26 06:23

本文关键词： 电动电位煤泥水伴生矿物 DLVO理论　出处：《太原理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：煤炭是我国的主体能源,湿法选煤造成大量待处理的煤泥水是影响选煤生产的关键因素,随着采煤机械化程度的增加,原煤中矸石含量也在增加,矸石中所含的粘土矿物是选煤过程中产生大量难沉降煤泥水的主要原因。论文通过样品的工业性分析、红外光谱分析、激光粒度分析及X衍射分析等对西山煤电集团马兰2#原煤的泥化特性、矿物赋存形式、粒度组成及矿物组成等进行了分析,发现马兰2#原煤中所含矿物成分主要为蒙脱石、高岭石、黄铁矿和石英。其中,高岭石与石英所占比例较大,原煤颗粒表面存在大量-OH、-C=O及-COOH等活性官能团。在深入分析马兰2#原煤性质基础上,通过改变溶液p H值、水质硬度、静态混合时间及动态混合时间,设计单因素试验,研究溶液性质及能量输入对原煤、不同粒度级煤样、不同密度级煤样、纯煤(C)、高岭土(K)、石英砂(Q)及其混合物电动电位的影响,结果表明:(1)各粒度级、密度级煤颗粒电动电位随溶液性质及能量输入变化而变化的趋势都基本相同。p H越小、水质硬度越大、与水混合时间越短,原煤颗粒电动电位越大,颗粒表面带电量越少。(2)溶液p H值增加时,矿物颗粒电动电位发生以下变化:纯煤与高岭土混合,高岭土含量高时混合颗粒电动电位减小,且C:K=1:1、C:K=1:3在p H=7.22、p H=8.36处取得零点电位;纯煤与石英砂混合矿物颗粒带负电,颗粒表面带电量随之减少;高岭土与石英砂混合矿物颗粒电动电位随之增加,p H=7时颗粒表面带电量最少,分别为 28.92mV、 26.73mV、随着水质硬度的提高,矿物颗粒表面Zeta电位都随之增大,颗粒表面带电量由所带电荷性质决定。(3)随着静态混合和动态混合时间的增加,纯煤与高岭土混合矿物颗粒电动电位随时间的增加而增加;纯煤与石英砂混合矿物颗粒电动电位随时间先增加后减小,最大值处表面带电量最少,分别为 18.57m V、 24.40mV、 30.77m V;高岭土与石英砂混合矿物颗粒表面带负电,且随静态混合时间的增加先减小后增加,时间等于24h处颗粒带电量最少,分别为 30.64mV、 29.60m V、 23.72mV,随动态混合时间的增加先增加后减小,在最大值处表面带电量最少,分别为 19.05mV、 22.07mV、 22.58m V。以上试验结果对煤泥水中胶体颗粒分散理论的完善,选煤厂药剂制度的确定,选煤厂煤泥水闭路循环的实现提供了理论依据,具有十分重要的工业应用价值。
[Abstract]:Coal is the main source of energy in our country. A large amount of coal slurry that needs to be treated by wet coal preparation is the key factor affecting the production of coal preparation. With the increase of mechanization of coal mining, the content of gangue in raw coal is also increasing. The clay minerals contained in the gangue are the main reasons for the production of a large amount of refractory slime water in the coal preparation process. Laser particle size analysis and X-ray diffraction analysis were carried out to analyze the mudding characteristics, mineral occurrence forms, granularity composition and mineral composition of Ma Lan 2# raw coal in Xishan Coal and Power Group. It was found that the mineral composition of Ma Lan 2# coal was mainly montmorillonite. Kaolinite, pyrite and quartz. Among them, kaolinite has a large proportion to quartz, and there are a large number of active functional groups such as -OH- OH- Cno and -COOH on the surface of raw coal particles. On the basis of in-depth analysis of the properties of Ma Lan 2# raw coal, the pH value of the solution is changed by changing the pH value of the solution. Water quality hardness, static mixing time and dynamic mixing time, single factor test was designed to study the effects of solution properties and energy input on raw coal, coal samples of different granularity and density, The effect of electromotive potential of pure coal, kaolinite, kaolinite, quartz sand and its mixture shows that the trend of the change of density coal particle electric potential with the change of solution property and energy input is basically the same as that of density grade coal particle at different granularity levels, the smaller the trend is, the smaller the electric potential of density grade coal particle is with the change of solution properties and energy input. The higher the hardness of water, the shorter the mixing time with water, the greater the electric potential of raw coal particles, the less charged amount of particle surface, the lower the pH value of solution), the following changes occur in the electric potential of mineral particles: pure coal mixed with kaolin, When the content of kaolin is high, the electrokinetic potential of mixed particles decreases, and the electric potential of mixed particles of pure coal and quartz sand decreases when the mixed mineral particles of pure coal and quartz sand have negative charge, and the electric potential of mixed particles in the mixture of pure coal and quartz sand decreases when the content of kaolin is high, and the electric potential of the mixed particle is obtained at the point of p H = 7.22 / p H = 8.36. The electric potential of mineral particles mixed with kaolin and quartz sand increased with the increase of electric potential, which was 28.92 MV and 26.73 MV, respectively. The surface Zeta potential of mineral particles increased with the increase of water hardness. The electric energy of the particle surface is determined by the charge properties of the particle. (3) with the increase of static mixing time and dynamic mixing time, the electric potential of pure coal and kaolin mixed mineral particles increases with the increase of time. The electric potential of mixed mineral particles of pure coal and quartz sand increases first and then decreases with time, and the surface electric energy at the maximum value is 18.57mV, 24.40mV, 30.77mV, respectively, and the surface of mixed mineral particles of kaolinite and quartz sand is negatively charged. With the increase of the static mixing time, the electric energy of the granular zone is the least, which is 30.64mV, 29.60mV, 23.72mV, respectively. With the increase of the dynamic mixing time, it increases first and then decreases, and the surface charge is the least at the maximum value. The above test results provide a theoretical basis for the improvement of the theory of colloidal particle dispersion in coal slurry, the determination of the preparation plant's medicament system and the realization of closed loop circulation of coal slurry in coal preparation plant, and have very important industrial application value.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD94

【参考文献】