Chen Dawei, Guo Xiaosong, Qi Zhenpeng, Gao Qun, Fu Jia, Wang Ruolin, Shao Huaizhi
China Coal Technology and Engineering Group Shenyang Design & Research Institute, Shenyang 110015, China.
School of Resources and Environmental Engineering, Shandong University of Technology, Zibo 255000, China.
ACS Omega. 2025 Jan 22;10(4):3960-3966. doi: 10.1021/acsomega.4c09798. eCollection 2025 Feb 4.
High-efficiency flotation of low-rank coal slime is an urgent problem to be solved in the comprehensive recycling and utilization of coal resources. The flotation results presented that the flotation effect of a single collector on low-rank coal slime was poor, which made it difficult to improve its flotation index. When dodecamine was added alone, the yield and ash of cleaned coal were higher at 79.15 and 18.74%, respectively. With dodecane added alone, the yield and ash were only 30.57% and 12.85%, respectively. When diesel oil was added alone, the yield and ash content were 47.25 and 14.68%, respectively. The compound collector can significantly improve the flotation effect of coal slime. The compound collector of diesel oil and dodecane can obtain a flotation index of 66.32% yield and 11.53% ash, and the compound collector of dodecane and dodecane can obtain a flotation index of 74.01% yield and 13.27% ash. The surface potential test revealed that the positive shift with the compound collector of dodecane-dodecamine and diesel-dodecane was greater than that with the compound collector of diesel-dodecamine, resulting in a better flotation effect. Meanwhile, the contact angle test found that the contact angle of coal slime with diesel-dodecane and dodecane-dodecamine was increased from 45.46 to 68.52 and 63.95°, respectively, which greatly increased the surface hydrophobicity and floatability of coal slime. Thus, an efficient flotation method of low-grade slime with a compound collector as the core is provided.
低阶煤泥的高效浮选是煤炭资源综合回收利用中亟待解决的问题。浮选结果表明，单一捕收剂对低阶煤泥的浮选效果较差，难以提高其浮选指标。单独添加十二胺时，精煤产率和灰分较高，分别为79.15%和18.74%。单独添加十二烷时，产率和灰分分别仅为30.57%和12.85%。单独添加柴油时，产率和灰分含量分别为47.25%和14.68%。复合捕收剂可显著提高煤泥的浮选效果。柴油与十二烷的复合捕收剂可获得产率为66.32%、灰分为11.53%的浮选指标，十二烷与十二胺的复合捕收剂可获得产率为74.01%、灰分为13.27%的浮选指标。表面电位测试表明，十二烷 - 十二胺和柴油 - 十二烷复合捕收剂使表面电位正向移动幅度大于柴油 - 十二胺复合捕收剂，浮选效果更好。同时，接触角测试发现，煤泥与柴油 - 十二烷和十二烷 - 十二胺的接触角分别从45.46°增大到68.52°和63.95°，大大提高了煤泥的表面疏水性和可浮性。由此，提供了一种以复合捕收剂为核心的低阶煤泥高效浮选方法。
