Column flotation as an effective strategy for trace element deportment control in coal cleaning

This study investigates the reduction of trace elements (Sb, As, Cd, Co, Cu, Cr, Mn, Ni, Zn, Pb, and V) in two Colombian coals, Caypa (La Guajira, northern-region) and Guachinte (Cauca, southwestern-region), using a flotation column test rig. The results revealed high differences in trace element removal between coal samples. Caypa coal exhibited the highest reductions for Pb (73.4%), Mn (69.9%), Cr (51.4%), and As (52.7%), whereas Guachinte coal showed maximum reductions for Mn (72.0%), Zn (49.7%), and Pb (39.1%). For Caypa coal, the maximum As reduction was achieved at 2.20 lb of Diesel oil/ton of coal and 2.67 lb of Flomin F-425/ton of coal. The highest reductions of Cr and Mn were obtained at 2.20 lb of Diesel oil/ton of coal with 4.45 lb of Flomin F-425/ton of coal. Pb reached its maximum reduction at 2.20 lb of Diesel oil/ton of coal and 0.89 lb of Flomin F-425/ton of coal. For Guachinte coal, the highest reductions of Mn and Zn occurred at 1.47 lb of Diesel oil/ton of coal and 1.78 lb of Flomin F-425/ton of coal, while Pb showed its maximum reduction at 3.67 lb of Diesel oil/ton of coal and 2.67 lb of Flomin F-425/ton of coal.