**2. Methodology**

Process design has evolved from inventions of recent design based upon experiments to today's novel process flow-sheet synthesis based-upon optimization. It responded to through a generation of process design based-upon the concept of stand-alone unit operations and therefor the integration between unit operations. The development of varied systematic design techniques supported on process integration has made it a promising tool in resource conservation activities. Improvement opportunities shall be identified either as process modification or design improvement as compared to the base case energy consumption regardless of the approach applied. As some approaches try to improve the energy performance of the facility design on extempore basis rather than developing it with an organized approach. Hence, it's important to define the base case energy consumption for measuring the performance enhancement so as to gauge the advance. The section is devoted to a number of approaches together with their advantages and dis-advantages which will use to boost the energy performance [6].
