摘要
利用K100表面张力仪接触角测量模块测定了4种煤样在浮选范围内的4个粒级的润湿性,研究了粒径对Washburn法测量结果的影响。当液体对固体的润湿能力很强或者很弱时,粒径的影响很弱可以放宽粒径范围;当颗粒与液体仅有部分亲和能力时,颗粒大小的影响非常显著,此时大颗粒的存在会影响实验结果的准确性。对于不同的液体,粒径大小的影响规律不同,以夹河煤样为例,在水中润湿曲线斜率的大小关系为k0.25～0.125>k0.125～0.074>k0.5～0.25>k0.074～0.038,在柴油中斜率的大小关系为k0.125～0.074>k0.25～0.125>k0.5～0.25>k0.074～0.038,对于其他煤样也有相似的情况,所以不能通过参比液的方法来消除粒径的影响。在常规浮选体系中,一般不能用Washburn法直接测量0.5 mm以下的固体的润湿性,为了提高测量结果的准确度,固体粒径范围最好控制在0.125 mm以下。
In order to get the range of particle size in which the measurement result is more accurate and reliable,the wettability of four different kinds of flotation coal,each of which were divided into four size fractions,has been measured by using the contract angle measuring module of K100 surface tension tester.The result shows that the difference in particle wettability affects the effect in particle size on Washburn equation.For Ji＇ ning coal,which is highly hydrophobic,the particle size has little influence.Ruqigou coal,which is strongly hydrophilic,satisfies the Washburn equation that the relationship of slopes is consistent with the particle size.And for Jiahe and Qianjiaying coal,which are partly hydrophilic,the relationship of slopes differ from the particle sizes.So when the wettability is very strong or very weak the effect of the particle size is very weak and the range of particle size can be relaxed.On the other hand,when the particles are partly hydrophilic,the effect of the particle size is very significant and large particles will affect the accuracy of the experimental results.For different liquid,the law of the particle size effect is different.Take Jiahe coal as an example.The relationship of the slopes for water and Jiahe coal is k0.25～0.125 k0.125～0.074 k0.5～0.25 k0.074～0.038,but for oil and Jiahe coal is k0.125～0.074 k0.25～0.125 k0.5～0.25 k0.074～0.038.And similar situations occure when using other coals.So the influence of particle size can＇t be removed by using reference liquid.In conventional flotation system,the wettability of particles whose size is less than 0.5 mm can＇t be measured directly with this method.And to increase the accuracy of measurement,the particle size should better be less than 0.125mm.
出处
《实验室研究与探索》
CAS
北大核心
2011年第12期17-20,共4页
Research and Exploration In Laboratory
基金
中央高校基本科研业务费专项资金项目(2010LKHX07)
