不同煤种接触角及润湿性规律探究

Study on Contact Angle and Wetting Property of Different Coal

为了确定粗糙度、表面活性剂以及变质程度对煤表面疏水性和润湿性的影响,选用5种不同变质程度的煤,测定了不同表面粗糙度煤样的表面接触角。并采用OWRK法理论模型计算不同变质程度、不同粗糙度煤的表面能。结果表明,粗糙度会影响煤表面的疏水性和润湿性,试验表明所选用的砂纸目数越小,煤样表面所测得接触角值越小,疏水性越差,煤表面能越大。不同表面活性剂对不同变质程度煤表面的润湿能力不同,对于褐煤和气煤,SDBS的润湿性最好,随着变质程度的增加,OP-10的润湿性较好;同一表面活性剂的不同浓度溶液,表面张力越小,润湿性越强;表面活性剂浓度在接近临界胶束浓度(CMC)时润湿效果较好。

In order to determine the influence of roughness, surfactant and degree of metamorphism on coal surfacehydrophobicity and wettability, surface contact angles of coal samples with different surface roughness were measured.The surface energy of coal with different degree of metamorphism and different roughness was calculated by OWRKtheory model. The results show that the roughness will affect the hydrophobicity and wettability of the coal surface. Theresults show that the smaller the number of sandpaper is, the smaller the contact angle is, the worse the hydrophobicityis, and the larger the surface energy of coal. The wetting ability of different surfactants was different for differentmetamorphic coal surface. For lignite and gas coal, the wettability of SDBS is the best, with the increase of the degreeof metamorphism, the wettability of OP-10 is better; Different concentrations of the same surfactant solution, thesmaller the surface tension, the stronger the wettability,and the wetting effect was the best when the concentration ofsurfactant was close to critical micelle concentration （CMC）.