疏水改性对选煤厂煤泥压滤特性的影响研究

发布时间：2018-06-22 05:14

本文选题：煤泥水 + 疏水改性　；参考：《安徽理工大学》2015年硕士论文

【摘要】：我国是世界上最大的煤炭生产国,选煤厂中煤泥脱水处理既是生产的重要环节又是难点。针对煤泥压滤循环周期长、煤泥水分高的问题,在不改变现有压滤设备和工艺的条件下向矿浆中加入助滤剂的方法对改善细粒物料的压滤效果就具有快速、简便、节省投资、见效快的优越性。论文提出了采用特定疏水改性药剂对选煤厂煤泥压滤特性的影响研究,拟通过该研究反映特定药剂对煤泥脱水的改善效果,为开发新型煤用助滤剂提供理论及技术支持。论文设计搭建了煤泥压滤脱水工艺试验系统,在试验系统上开展了药剂种类、药剂用量、煤泥水性质、工艺操作条件等对煤泥压滤特性的影响,并进行了压滤条件的优化。研究表明：1)随着药剂用量的增加,一定范围内压滤脱水滤饼水分发生了大幅度的降低,药剂用量500g/t左右的时降至最低,之后滤饼水分逐渐升高,说明药剂用量过高时会使过滤速率降低,滤饼含水率增加。2)对比三种疏水改性药剂滤饼水分最大增降绝对值,药剂用量为500g/t时,1#药剂为1.50%,2#药剂为2.09%,3#药剂为2.25%,得出3#药剂在药剂最优点上对滤饼改善效果最好,1#药剂改善作用最弱。三种疏水改性药剂对煤泥助滤效果明显。3)对比疏水改性药剂、十二烷基硫酸钠、阴离子1000万的高分子聚丙烯酰胺以及聚合氯化铝对压滤效果的影响,发现疏水改性药剂对压滤脱水的助滤效果最好,煤泥颗粒表面的疏水改性对压滤影响很大。4)随着入料压力的增加,一定范围内入料压力越大,滤饼的水分越低。且药剂用量在最佳药剂点时随入料压力的增加使滤饼水分减小程度最大。5)随着试样粗颗粒含量的降低,粒度级向细粒级方向发展,压滤所得滤饼的水分总体呈增长趋势,说明入料煤泥水粒度组成越细,疏水改性药剂的助滤效果越差。6)添加的石英、高岭土、伊利石、蒙脱石四种矿物都不同程度的恶化了压滤脱水过程,滤饼水分都要高于空白试样值。7)通过观察并对比分析滤饼内部孔隙结构显微成像得出：空白试验得到的滤饼内部结构致密。添加疏水改性药剂的滤饼中微小颗粒的数量显著减少,滤饼结构变得疏松。说明试样煤泥在特定疏水改性药剂作用下增强了过滤和脱水的能力。
[Abstract]:China is the largest coal producing country in the world. Sludge dewatering is not only an important link but also a difficult point in coal preparation plant. In view of the problem of long cycle and high water content of coal slime, the method of adding filter aids to the slurry without changing the existing pressure filtration equipment and technology has the advantages of fast, simple and economical investment to improve the pressure filtration effect of fine grain material. The superiority of quick effect. In this paper, the influence of specific hydrophobic modifier on the pressure filtration characteristics of coal slime in coal preparation plant is studied. The research is intended to reflect the improvement effect of specific agent on sludge dehydration, and to provide theoretical and technical support for the development of new filter aid for coal. In this paper, a coal slurry filtration and dehydration process test system is designed and built. The effects of the type of reagent, dosage of reagent, slurry properties and operation conditions on the pressure filtration characteristics of coal slime are carried out on the test system, and the pressure filtration conditions are optimized. The results showed that the moisture content of filter cake decreased greatly with the increase of the dosage of the reagent, and the water content of filter cake increased gradually when the dosage of 500g/t decreased to the lowest. The results show that the filtration rate will be decreased when the dosage of medicament is too high, and the moisture content of filter cake will increase by .2) compared with three kinds of hydrophobic modified fungicide filter cake, the maximum increase of water content of filter cake will decrease the absolute value. When the dosage of 500g/t was 1.501#, the dose was 2.092# and 2.251#. It was concluded that the medicament had the best effect on the filter cake improvement on the best advantage and the weakest effect on the filter cake improvement. Compared with hydrophobic agent, sodium dodecyl sulfate, anionic polymer polyacrylamide (10 million) and polyaluminum chloride (PACL), the influence of hydrophobic agent on pressure filtration was studied. It was found that hydrophobic modifier had the best effect on filtration and dehydration, and hydrophobic modification on the surface of coal slime had great influence on pressure filtration.) with the increase of feed pressure, the bigger the feed pressure was, the lower the water content of filter cake was. With the increase of feed pressure, the moisture content of filter cake decreased to a maximum of 5. 5) with the decrease of coarse particle content of the sample, the grain size level developed to fine grain level, and the moisture content of filter cake obtained by pressure filtration showed an increasing trend. It shows that the finer the granularity composition of the coal slurry, the worse the filtration aid effect of the hydrophobic modifier is (.6) the process of filtration dehydration is aggravated by the addition of quartz, kaolin, Illite and montmorillonite to varying degrees. The moisture content of filter cake is higher than that of blank sample (7) by observing and comparing the pore structure of filter cake, it is concluded that the inner structure of filter cake obtained by blank test is compact. The number of tiny particles in filter cake with hydrophobic modification agent decreased significantly, and the structure of filter cake became loose. The results show that the filter and dehydration ability of sample slime is enhanced under the action of hydrophobic modifier.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD94

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