Conventional flotation technology has historically failed to achieve high recoveries when treating <15 m particles (lynch et al, 1981). the new stackcell flotation technology was developed to specifically target this particle size range, and was tested at pilot plant scale at mt keith nickel concentrator. the streams tested, slimes rougher tailings and fines slimes cleaner tailings, represent 21% and 11% of the total nickel lost to tailings in the plant. laboratory scale test work indicated that an economically significant fraction of these losses was consistently available to be recovered by additional flotation. the pilot plant experimental scope included over 50 tests. a grade recovery curve for each stream was developed, as well as information on the effect of ore type, feed rate, wash water, air flow, collector and frother on the performance of the cell. the single stackcell was able to achieve nickel recoveries of 16.8% and 16.5% on the rougher tailings and cleaner tailings, respectively, at grades consistent with these blocks. additional test work of the stackcell in a cleaner scalper duty yielded final quality concentrate with a maximum nickel recovery of 59.5% for the single stage stackcell. laboratory scale simulation of the downstream impacts of the stackcell operating as a cleaner scalper indicated a net recovery benefit of up to 2.0% for this cleaner block.tests were completed to compare residence time requirements of the stackcell, as compared to conventional flotation. in 55 seconds, the pilot plant stackcell achieved 50% of the recovery of a 960 second laboratory scale conventional flotation on the same feed material. the apparent improvement in flotation kinetics is attributed to the novel high intensity aeration system, which provides efficient bubble-particle contact thereby shortening the residence time required to achieve high recoveries. the smaller footprint and lower energy costs of such a cell are also benefits of this technology, which is being considered for industrial scale installation as a result of this test work. given the industry's historical poor performance treating slimes with conventional flotation, it is clearly best practice to challenge the status quo through innovative new technology, such as the stackcell.citation:hussey, l, thanasekaran, h and kohmuench, j, 2017. the application of high intensity flotation technology at mt keith nickel concentrator, in proceedings metplant 2017, pp 259-278 (the australasian institute of mining and metallurgy: melbourne).>