Currently the conceptual design stage is greatly facilitated by the use of simulations, either in a design of a new plant or in conducting improvement studies in an existing

However, the simulation approach suffers from lack of synthesis capability and inability to provide an overall contextual overview of the entire plant. This drawback at the conceptual design stage will have serious consequences in determining the environmental impact, economic viability and safety features of the final designKnowledge of Process Integration is essential in arriving at better designs that will meet the calls for efficiency in the use of energy, efficiency in the use of materials and reduction of emissions.?