Abstract: In this work, a mathematical model has been developed for the simulation of multiple effect evaporators (MEE) system from a set of non-linear equations, Evaporation is the most energy intensive unit in pulp and paper industries, feed and product flashing, condensate, boiling point rise, vapour bleeding, etc are considered to reduce energy consumption. An inquiry into PZ PLC, a manufacturing industry situated in Aba, Abia state; for concentrating liquor using falling film plate evaporator in steam splitting in the first two effects to generate vapour used in vapour bodies within the system. Evaporation is the removal of solvent as vapour from a solution. It is the operation which is used for concentration of solution. There could be single effect evaporator or multiple effect evaporators. With addition of each effect steam economy of the system also increases. Evaporators are integral part of a number of a process industry like Pulp and Paper, Sugar, Caustic Soda, Pharmaceuticals, Desalination, Dairy and Food Processing etc. Caustic Soda Industry is of present interest. The system consists of triple effect having falling film evaporator as each effect. There is forward feed and backward feed flow. This paper describes a steady state model of multiple effect evaporators for simulation purpose. The model includes overall as well as component mass balance equations, energy balance equations and heat transfer rate equations for area calculation for all the effects. Each effect in the process is represented by a number of variables which are related by the energy and material balance equations for the feed, product and vapour flow for forward feed & backward feed, The results of present work with concentration in effect-I at 0.853558 was validated against previous work of (Kumar and Zain, 1996) at 0.7942216 and it shows close agreement. Also considering a backward result of effect-III product L_(3 )as 0.327396 while that of (Kumar and Zain, 1996) as 0.398923 fro