Without any doubt the development of column cells has been one the most important advances on the design and operation of flotation plants. The benefits of column cells are associated to metallurgical performance and reduction of operating costs. Column cells have been used exclusively for concentrate cleaning where the tall froth column, quiescent surface conditions and countercurrent flow make possible that a single column cell to replace two or four stages of conventional cleaning with mechanical cells. Production risks are also lower and the key benefit lies in increases of up to 4% to 6% in concentrate grade with increased revenues and reduced operating costs for power, maintenance and personnel.
Economically, column cells are easy to operate and are paid for themselves in a matter of months. It is important to indicate that column cells are not appropriate for rougher flotation and all the benefits on metallurgy and economy depends of its application in the cleaner circuit. Basically, a company with a new project or an expansion must be aware of this aspect. The main issue is the coarse particle size of rougher flotation. Since the rougher flotation circuit is responsible for the recovery of valuable metals, it is important to design the circuit with conventional cells. Mechanical cells have restriction in cleaning and the best way to optimize results is to install column cells in cleaning.
Other important aspect of column cells is related to the simple lay out required. It is extremely simple compared with conventional cells. Other benefit is that low grade ores can be treated successfully when the cleaner circuit was designed with column cells. There are some gold operations with slimes problems whose final concentrate grade was improved with column cells. Operations using mechanical cells try to minimize the problem by performing selecting blasting and mining. Nevertheless, the inventory of material untreated is higher and the economy of the project or operation is affected by this partial solution. The gold ore stockpiled has an impact on the cash flow of the project or the estimated production of the month.
Column cells increase gold concentrate grade