Abstract: An introduction is made in the paper to the structural design and working principle of the XJMKS45 3 + 2 type flotation cell,as well as the special features of the cell—use of mineralization device to effect preliminary flotation of feed pulp in form of mineralized microbubbles,ability to effect self-suction through agitation with pump-type double-layer umbrella-formed impeller,and flexible switch-over between primary and secondary flotation processes.Field application of the machine at Lulin Nenghua Coal Preparation Plant indicates that: the machine operates with a pulp throughput as high as 1 000 1 300 m~3/h;when used for treating a feed with an average ash of 23.67%,the following remarkable result can be expected: concentrate ash—9.27,concentrate yield—66.49,average recovery rate of combustible matter -79.02%,mean flotation perfection index—up to 44.25%.