Liao Yinfei, Ren Hourui, An Maoyan, Cao Yijun, Yang Zhe, Hao Xiaodong, Song Xingwei
National Engineering Research Center of Coal Preparation and Purification, China University of Mining and Technology, Xuzhou 221116, Jiangsu, PR China.
School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, PR China.
ACS Omega. 2021 Mar 15;6(11):7746-7753. doi: 10.1021/acsomega.1c00099. eCollection 2021 Mar 23.
It is well known that mixed collectors can effectively strengthen the flotation of low-rank coal. However, less concern has been paid to the detachment of low-rank coal flotation using mixed collectors. In this study, the force of air bubble detachment from low-rank coal surface treated by oleic acid (OA), dodecane (D), and oleic acid-dodecane (OA-D) collector mixture was investigated using microforce balance. The results showed that the process of bubble detachment from the low-rank coal surface was divided into three stages: relaxation stage, stretching stage, and sliding stage. The equilibrium contact angle and critical contact angle were the transition points between different stages. The order of detachment force required for bubble detachment from the surface of low-rank coal was OA-D > OA > D, indicating a synergistic effect between OA and D. Based on the three parameters of equilibrium contact angle, critical contact angle, and contact line length, a theoretical model was proposed to calculate the detachment force. The calculated results were in agreement with the measured results.
众所周知，混合捕收剂能有效强化低阶煤的浮选。然而，对于使用混合捕收剂进行低阶煤浮选时气泡的脱离关注较少。在本研究中，利用微力天平研究了油酸（OA）、十二烷（D）以及油酸 - 十二烷（OA - D）捕收剂混合物处理的低阶煤表面气泡脱离的力。结果表明，低阶煤表面气泡脱离过程分为三个阶段：松弛阶段、拉伸阶段和滑动阶段。平衡接触角和临界接触角是不同阶段之间的转变点。低阶煤表面气泡脱离所需脱离力的顺序为OA - D > OA > D，表明OA和D之间存在协同效应。基于平衡接触角、临界接触角和接触线长度这三个参数，提出了一个计算脱离力的理论模型。计算结果与测量结果一致。
