Nano-microbubble flotation of fine and ultrafine chalcopyrite particles

• Published in: International journal of mining science and technology Vol. 24; no. 4; pp. 559 - 566
• Main Authors: Ahmadi, Rahman, Khodadadi, Darban Ahmad, Abdollahy, Mahmoud, Fan, Maoming
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.07.2014; Department of Mineral Processing Engineering, Tarbiat Modares University, Tehran 111-14115, Iran%EFD, Eriez Manufacturing Co., Erie, PA, USA; Elsevier
• Subjects: Bubble size distribution; Chalcopyrite; Fine particles; Froth flotation; Nano-microbubble; Nanobubbles; 实验室规模; 微泡浮选; 气泡尺寸; 浮选回收率; 浮选试验; 纳米; 超细颗粒; 黄铜矿; Nano-microbubble; Nanobubbles; Chalcopyrite; Bubble size distribution; Fine particles; Froth flotation
• ISSN: 2095-2686
• DOI: 10.1016/j.ijmst.2014.05.021

As is well known to mineral processing scientists and engineers, fine and ultrafine particles are difficult to float mainly due to the low bubble-particle collision efficiencies. Though many efforts have been made to improve flotation performance of fine and ultrafine particles, there is still much more to be done. In this paper, the effects of nano-microbubbles （nanobuhbles and microbubbles） on the flotation of fine （-38 ＋ 14.36 μm） and ultrafine （-14.36 ＋ 5μm） chalcopyrite particles were investigated in a laboratory scale Denver flotation cell. Nano-microbubbles were generated using a specially-designed nano- microbubble generator based on the cavitation phenomenon in Venturi tubes. In order to better under- stand the mechanisms of nano-microbubble enhanced froth flotation of fine and ultrafine chalcopyrite particles, the nano-microbubble size distribution, stability and the effect of frother concentration on nano- bubble size were also studied by a laser diffraction method. Comparative flotation tests were performed in the presence and absence of nano-microbubbles to evaluate their impact on the fine and ultrafine chalcopyrite particle flotation recovery. According to the results, the mean size of nano-microbubbles increased over time, and decreased with increase of frother concentration. The laboratory-scale flotation test results indicated that flotation recovery of chalcopyrite fine and ultrafine particles increased by approximately 16-21% in the presence of nano-microbubbles, depending on operating conditions of the process. The presence of nano-microbubbles increased the recovery of ultrafine particles （-14.36 ＋ 5 μm） more than that of fine particles （-38 ＋ 14.36 μm）. Another major advantage is that the use of nano-microbubbles reduced the collector and frother consumptions by up to 75% and 50%, respectively.