This study presents experimental and theoretical investigations of bulk solid transport in a pilot-scale horizontal rotating drum with segmented lifters. A number of lifters with different dimensions and arrangements were specially designed. The results show that the axial bed depth profile strongly depends on lifter type and geometry as well as degree of loadings. A flat bed depth profile with relatively low total volumetric filling fraction, which is necessary for good heat transfer performance, can be achieved. A simplified theoretical transport model has been developed to estimate the axial bed depth as a function of key engineering parameters. The model prediction gives good agreement with experimental data within the range of cases considered in this study.