Pinch analysis method for total site energy integration and retrofit using in oil refining

Based on the total site pinch analysis with composite curves, the paper presents an improved method of total site energy integration synthesis for multi-processes, heat exchanger network and utility system. After fully heat-exchanged inner individual processes, the further integration for residual heat sources and sinks with utility system can be made. By making use of the rules of steam load plus/minus and steam load remove on the total composite curves, the fuel can be saved more and the cogeneration potential power can be increased. An energy integration example illustrates that the improved method can approach the targets of minimum utility usage or maximum co-generation power, and the increase of economic benefits is effective.