Abstract: There have been seen a series of problems with the operation of the NTB45Y rake tthickener because of its ageing. To tackle the problems and in line with the plant′s specific operating conditions, an optimized technical scheme is adopted to replace the thickener in an integral manner. Practice shows that the use of the technique can meet the production requirements and is high in efficiency with a favorable economic result because of the acceleration of the thickener erection progress, elimination of fitting errors, reduction of reworking and cut-down to a certain extent of erection cost.