The need for efficient energy use in refinery operations is the proffered solution to the poor management of energy resources which has resulted in the instability in oil products prices, irregular plant shutdowns experienced in refineries of developing countries and increased carbon emission to the atmosphere. This research work aims to carry out exergy analysis on major energy consuming units which will aid in determining sites and causes of primary energy losses and proffer solutions to maximizing energy utilization. The Naphtha Hydro-treating (NHT) unit of the case model refinery was successfully simulated using Aspen Hysys. The analysis revealed more than half (51.9 %) of the input exergy was lost to the environment and an irreversibility of 32.7% occurred in the Stripper column. Comparison was also made with the same unit at Kaduna refinery and petrochemical plant and the results showed a conversion efficiency of about 91.28% when compared to 44.35% from the old refinery though this could be attributed to factors like age of plant, inadequate maintenance etc. The positive value of the amount of heat recovered from that of the flue gas in the boiler and furnace gave an opportunity to recover the energy lost and integrated back to the system for economic viability of the plant which result in a payback period that is less than a year.
Agha MH. Integrated Management of Energy and Production: Scheduling of Batch and Continuous Heat and Power Plant;[Internet] 2009. Available from: https//oatao.univ-toulouse.fr/7872/1/agha.
Agbo AF.AbojeAA,ObayomiKS. Exergy Analysis of Naphtha Hydrotreating Unit. Journal of Physics: Conference Series.2019; 1299(1): 012025.
Energy Agency (IEA). World Energy Outlook. [Internet] 2011. Available from: https://www.iea.org/topics/world-energy-outlook
Ghannadzadeh A. Exergetic Balances and Analysis in a ProcessSimulator: A Way to Enhance Process Energy Integration. [Internet] 2012. Available from:http://ethesis.inp-tolouse.fr.
Dincer I. Exergy as a Potential Tool for Sustainable Drying System Sustainable Cities and Society. 2011; 1: 91-96.
Omar MA, Abdulla AA,Zin ED. Exergy Analysis of a Power Plant in Abu Dhabi. International Journal of Energy Engineering. 2015; 5: 43-56.
Al- Muslim, Dincer I, Zubair SM. Effect of reference state on exergy efficiencies of one and twostage crude oil distillation plants. International Journal of Thermal Science. 2005; 44: 65-73.
Dincer I,Al- Muslim H. Thermodynamics Analysis of reheat cycle stream power plants. International Journal of Energy Reserves.2001; 25: 729-739.
Dincer I. The role of exergy in energy policy making. Energy Policy. 2002; 30: 137-149.
Hydroprocessing Process Technology, Process Flow and Equipment, Dangote Oil Refining Co., UOP LLC Honeywell Company Manual. 2019.
Hydroprocessing Process Technology, Introduction, catalyst and chemistry, Dangote Oil Refining Co., UOP LLC Honeywell Company Manual.2019.
Hydroprocessing Process Technology, Overview of MS-Block Hydro treating Unit (NHT), Continuous Catalytic Reformer, Penex Unit., Dangote Oil Refining Co., UOP LLC Honeywell Company Manual.2019.
Hart Resources Limited. Nigeria Extractive Industries Transparency Initiative: Refineries and Product Importation. Hart Resources Ltd. 2012.
Abdulqahar SN, Abdulwahab MI, &Hummadi KK. Reuse of Spent Hydrotreating Catalyst of the Middle Petroleum Fractions.Iraqi Journal of Chemical and Petroleum Engineering.2019;20(1): 15–22.
Nigerian National Petroleum Corporation Kaduna Refinery. Atmospheric Distillation Unit Laboratory Operating Manual and Process Flow Diagram. Yokohama, Japan:Chiyoda Chemical Engineering and Construction Company Ltd.2015.
Aspen HYSYS® Dynamics V8.6. [Internet] 2015. Available from:www.aspentech.com
Nuhu M, Olawale AS, Salahudeen N, Yusuf AZ, Mustapha Y. Exergy and Energy Analysis of FCCU. International Journal of Chemical Engineering and Applications. 2012; 3: 441-445.
Hasanuzzaman M, Saidur R, Masjuki HH. Effects of Operating Variables on Heat Transfer and Energy Consumption of a Household Refrigerator-Freezer during Closed Door Operation. Energy.2009; 34(2): 196- 198.
Saidur R, Lai YK, Reducing Boiler Flue Gas Temperature and Associated Energy Savings Using Nanofluids and Nano surfaces. Energy Policy, under review.2009.
Saidur R, Rahim NA, Ping HW, Jahirul MI, Mekhilef S, Masjuki HH. Energy and emission analysis for industrial motors in Malaysia. 2009.
Kinsey JL, White ML, Hebaue TC. Air Recuperator for Combustion. U.S. Patent No. 6,019,598. Washington, DC: U.S. Patent and Trademark Office. 2010.
Saidur R, Ahmed JU, Masjuki HH. Energy, exergy and Economic Analysis for Industrial Boilers for Malaysia. Energy Policy.2010; 38: 2188-2197.
Rosen M, Bulacea C. Using Exergy Analysis to Understand and Improve the Efficiency of Electrical Power Technologies. Entropy. 2009; 11: 820-835.
Odejobi JO. Exergy and Economic Analyses of Crude Oil Distillation Unit. African Journal of Engineering Research. 2015; 3:44-55.
Hasanuzzaman M, Rahim NA, Saidur R, Kazi SN. Energy Savings and Emissions Reductions for Rewinding and Replacement of Industrial Motor.Energy.2011; 36(1): 233-240.