Jameson Cell Scale-Up Experiences at Australia's BHP Coal's Goonyella Coal Preparation Plant

摘要

In 1993, BHP Coal investigated several different flotation technologies for the replacement of the ageing mechanical (sands) flotation cells in it's Goonyella coal preparation plant. The study included pilot scale testing using two 0.5 metre (1.6') diameter Jameson Cells, having a throughput of 7.5 m~3/h (33 USGPM). The results showed that the cell could deliver superior metallurgical results compared to the mechanical flotation cells. In the following year, BHP Coal decided to replace the mechanical cells with Jameson Cells installed in a two stage (rougher - scavenger) configuration. In 1995, BHP Coal initiated a project to confirm the ability of Jameson Cells to be scaled up from pilot to industrial scale. The aim of the study was to determine whether the full scale downcomer could deliver the results predicted by test work with a smaller sized downcomer. For the scale-up confirmation study, BHP Coal purchased two demonstration scale Jameson Cells, each having a diameter of 1.25 metres (4'), and a full-scale, 60 m~3/h (264 USGPM) capacity downcomer. The size of the demonstration cell's tank was calculated using parameters determined during the pilot scale test work. The results from the demonstration scale trials were found to be in line with the pilot scale results. Having demonstrated the scale up from the pilot scale Jameson Cell to the demonstration scale cells with industrial scale downcomers, BHP Australia Coal proceeded with the installation of eight model 5000/16 cells (16.5' diameter cell with 16 downcomers) in two-stage, in series, configuration. These industrial scale Jameson Cells, each treating 960 m~3/h (4227 USGPM) used the same size downcomer as the demonstration cell. The installation of the Jameson Cells at Goonyella was part of a major fines circuit upgrade. Commissioning of the refurbished fines circuit was completed in two weeks, with maximum throughputs achieved shortly thereafter. The full-scale Jameson Cell optimisation data are seen to closely match the pilot scale performance data. The results show that the pilot scale tests were able to accurately predict the performance of the full-scale Jameson Cells. Several months of Jameson Cell operating data show that the full-scale installation has consistently been able to deliver the results predicted by the pilot scale testing. The Jameson Cell's performance is also demonstrated to be much less variable than that of the preceding mechanical flotation cells. The ability of the Jameson Cell to deliver a consistently low ash product has allowed the recoveries from the coarse circuit to be increased, thereby paving the way for a 3.5% increase in plant yield, and the setting of BHP Coal production records.