Crude glycerol, as a side product of biodiesel production from plant oils such as crude palm oil, could be upgraded to become an economically high-value added purified product for food and pharmaceutical additives. However, its purification is a challenging problem because of the application of vacuum distillation column using multiple stage ejectors. In this paper, purification of crude glycerol is simulated using (L/D)V control configuration in ASPEN PLUS environment. The selection of operating conditions is investigated to obtain commercial glycerol purity. In addition, operational considerations are discussed including the usage of the stage temperature to infer the glycerol purity. At constant reflux ratio, the simulation results show that increasing the reboiler duty can increase the glycerol purity. Moreover, the higher glycerol purity can be obtained using higher reboiler duty at higher reflux ratio. However, output multiplicity is observed because there are two distinct glycerol purities resulting from the same operating conditions. Based on the steady state process sensitivity, the temperature at the bottom column is a reasonable candidate to infer the glycerol purity of the bottom product. The relationship between the bottom temperature and the glycerol purity is quite linear around the selected operating conditions. Besides, the bottom temperature is monotonously increasing with increasing the reboiler duty. As a result, the (L/D)V configuration can be employed to control the bottom temperature as an inferential variable for the glycerol purity by manipulating the reboiler duty.