In a process, variables can be classified into controlled and manipulated variables. Most of these variables are attached, as in the case of a distillation unit. To resolve this type of models, it is necessary to uncouple the process variables and to design multiple monovariable drivers. When interactions cannot be avoided, the multivariable process must be considered. This article presents the design of a proportional, integral and derivative multivariable controller, using the Biggest Log Modulus Tunning (BLT) algorithm. Considering the detaching structure, the validation of the Multi-Input Multi-Output (MIMO) system, and the binary distillation column used to separate methanol and water, which identifies the model in state space used for the design of the controller are presented. This paper seeks to contribute by proposing a generic model for estimating the desired behavior of the controlled model, based on mathematical foundations and reinforcing a method for calculating the controller as the Biggest Log Modulus Tunning (BLT) algorithm. The results are obtained in simulation for various studied cases.