Energy optimization of a Multiple Effect Evaporator house employed in the concentration of black liquor during Kraft Recovery process of Paper industries is an eye-catching concern pertinent to the present-day energy scenario. This article presents a proficient approach to solve the energy optimization problem of Multiple Effect Evaporator via metaheuristic optimizers. The proposed method first transforms the energy balance equations into the objective function to be optimized. Three metaheuristic algorithms viz. Harmony Search, Imperialist Competitive Algorithm and Water Cycle Algorithm have been utilized to carry out the optimization task. These metaheuristic approaches effectively figure out the optimum values of various process parameters including steam consumption, vapor temperatures and liquor flow rates, thereby yielding the optimum Steam Economy. Further, the present work investigates the effect of Boiling Point Elevation on the system performance. The results reveal that the inclusion of Boiling Point Elevation in the mathematical model causes a reduction in Steam Economy by 3.89%. The results also demonstrate the proficiency of these metaheuristic approaches towards the solution of a complex set of simultaneous non-linear algebraic equations. For comparative investigation of these metaheuristic approaches with reference to system performance parameters, tabular, evocative and graphical demonstrations have been utilized. Moreover, with the purpose of validating the strength, efficiency and exploratory capabilities of these metaheuristic algorithms, the acquired optimization results are compared with other competent and eminent algorithms to make a comprehensive evaluation.