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Control of process parameters is one of the important problems in process industry. The process considered for modeling is spherical tank liquid level system. Control of liquid level in a spherical tank is nonlinear due to the variation in the area of cross section of the level system with change in shape. System identification of this nonlinear process is done using black box model, which is identified to be nonlinear and approximated to be a First Order Plus Dead Time (FOPDT) model. Here the controller design is compared based on conventional Proportional Integral (PI) based on Ziegler-Nicholas settings with Internal Model Control (IMC) based on Skogestad’s settings. The real time implementation of the process is designed and implemented in MATLAB using ADAM’s data acquisition module. Out of the control algorithms IMC outperforms in no overshoot, faster settling time, better set point tracking and produces lower performance indices.