Loading...

Assessment and Optimization of Exergoeconomic Cost of Energy Carrier Products of Multi-product Plants

Kazemi Namin, Matin | 2024

0 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 57546 (46)
  4. University: Sharif University of Technology
  5. Department: Energy Engineering
  6. Advisor(s): Khajehpour, Hossein
  7. Abstract:
  8. The present study deals with the exergoeconomic analysis in a petrochemical industry utility supply complex. Discovering the levelized cost of products based on the economic valuation of exergy destruction in the system in a way that helps to continue the life of utility plsnts, and offers the right price to customers; It is of great importance. In this research, using exergy analysis with the help of EES software, the thermodynamic characteristics of the studied units are calculated. By simultaneously solving the exergy cost balance equations of the units based on the thermodynamic and economic data of the system, the levelized cost of products and other exergeoeconomic characteristics are calculated for the base scenario. The results show that the power plant unit with 1148.50 MW has the highest sum of total destruction and exergy losses, the instrument air production unit has the highest exergy efficiency equal to 66.21%, the oxygen unit with 38.50 M$y has the highest destruction cost and the condensate polishing unit has the highest exergoeconomic coefficient with 98.47%. In the next step, by selecting the Improvement Strategies based on practical and theoretical criterias, the systemic effect of the changes applied in the selected Improvement Strategies on the levelized cost of products is calculated with the help of the Input-Output model, based on which, the lowest cost of steam with 1.5624 $100kg in the scenario of "Cooling the inlet air of gas turbines", the lowest cost of electricity production in the scenario of "Reducing the temperature of closed circuit cooling water" is realized with 0.0314 $kWh and the lowest cost of oxygen production in the base scenario is equal to 0.0787 $Nm3. In the following, considering the nature of cost-benefit among different variables in system, the basis of optimization is considered with the aim of minimizing the total cost of system in terms of total destruction and exergy losses for each of the scenarios and finally, determining the scenario with investment priority is considered. The results indicate that the minimum amount of total cost is equal to 704.40 M$y and the sum of total destruction and exergy losses is equal to 1897 MW and is near the corresponding point of the base scenario. The scenario of "Reducing the temperature of closed circuit cooling water" is the closest strategies to the optimal state and the base scenario. The low price of the fuel gas consumed by the system is one of the most important reasons for the results obtained regarding the distance between the strategies and the optimal point. In fact, with the current gas prices, there is not much difference between the improvement priorities and the reduction of fuel consumption does not create a specific change in costs. In this regard, with the help of Sensitivity Analysis on the price of gas, it was observed that at higher prices the changes become significant and the lowest total cost of the system will be awarded to the strategy of "Replacing efficient gas turbines in the power plant"
  9. Keywords:
  10. Exergy ; Exergo Economic Analysis ; Levelized Energy Cost (LEC) ; Optimization ; Utility System ; Energy Life Cost ; Input-Output Analysis

 Digital Object List

 Bookmark

No TOC