STRATEGY TO IMPROVE ENERGY EFFICIENCY OF HEAT EXCHANGER NETWORK IN MODIFIED CRUDE OIL DISTILLATION PROCESS

• Main Author: Ambya Fahira, Dini
• Format: Theses
• Language: Indonesia
• Subjects: Teknik kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/70742
• Institution: Institut Teknologi Bandung

A petroleum refinery is known for its major energy demands where a refinery with a capacity of 290,000 barrels/day has a total energy requirement of 59.7 x 1012 MJ/year. From this figure, energy consumption for power and steam generation reaches 35.4 x 1012 MJ/year or almost 60% of the total energy demand. Significant utility requirements are an early sign of energy inefficiency in a system which results in high operating costs. Pinch analysis has shown excellent success in increasing the energy efficiency of a process. The energy evaluation carried out on the existing HEN (Heat Exchanger Network) shows that the pinch design is still inefficient and has gaps for optimization. The concept of minimizing exergy lost which then applied to the principle of pinch analysis is the optimization strategy carried out in this study. With this method, the temperature interval line on the HE design diagram is increased so that the matching of hot and cold flows can occur at equal temperature intervals. The results of the optimization succeeded in reducing the total utility requirement by 43% from the initial value of 4.29 x 108 kJ/hour to 2.43 x 108 kJ/hour. The heating utility managed to decrease by 39.6% from the initial value of 2.56 x 108 kJ/hour to 1.54 x 108 kJ/hour and the cooling utility could be reduced from the initial value of 1.73 x 108 kJ/hour to 8.87 x 107 kJ/hour or decreased by 48.7%. From the economic analysis, it was found that HEN optimization scheme requires a capital cost of 51 million USD with a payback period of 3.96 years. All results achieved from energy optimization are obtained without changing or reducing the quality and production rate of petroleum products. Hence it can be concluded that the proposed heat exchanger network optimization design is economically feasible to implement. However, the thing that needs to be considered in realizing this optimization design is the constraint of land availability which requires adjustments to the layout of existing equipment which is expected to require significant time and costs. Therefore, the heat exchanger network optimization strategy in this study will be more beneficial if applied to a new refinery construction project.