Simulation of foam separation has been reported usually for two-component systems. In this paper, a mathematical model is developed to describe the process of foam separation of tributyl phosphate (TBP) from aqueous solutions using sodium dodecyl sulphate (SDS) as surfactant. The model assumed that the bubbles are uniform in size and have regular dodecahedral structure. The solution in the liquid pool has uniform concentration and the enrichment is completed in the course of film drainage. The model is calculated under different operating parameters. The calculated results show that by decreasing the bubble size and equilibrium height or by increasing the foam height and equilibrium coefficient will improve the foam separation efficiency. If the operating parameters can be controlled by just increase the gas how rate, the recovery concentration of TBP will not be influenced.