This study introduces a new approach for the conceptual design of an offshore topside process, satisfying environmental standards, saving utility consumption, and consequently, maximizing economic profit. Twelve individual processes are modeled as a case study, based on sets of combinations between four topside process configurations and three individual production scenarios (i.e., peak oil, peak gas, and peak water) over the life cycle of an oil reservoir. Then, the simulation results of these models are analyzed based on economic profit. In particular, the simulation program is integrated with a mixed-integer non-linear programming algorithm to optimize the design and operating variables (e.g., operating pressures of the multi-stage separators) in order to maximize the economic profit of the platform. Lastly, an economic feasibility study is performed for the design of a profitable and eco-friendly offshore platform.