The present study suggests a new scheme to design a decentralized PI controller for two input two output (Trio) processes. The decentralized controller is obtained from the direct synthesis method. The decoupler is derived from a modified decoupler and minimizes the interaction between the loops. Then a new reduced method based on equivalent transfer function (ETF) with relative gain array concept and relative normalized relative gain array concept reduces the decoupled process transfer functions to first-order plus time delay (FORTE)) forms. Further, two RI controllers are obtained in the proposed delay compensated configuration in terms of the only parameter in every individual loop for the FOPTD transfer functions. Three illustrative examples demonstrate that the performance is verified on the original interactive system and show the effectiveness of the proposed design method. The results confirm the superior performance of the proposed compensation configuration in nominal and robust cases. The proposed method also offers several important advantages compared to other previous methods.