PTQ Q4 2023 Issue

Diesel yield wt%

AAD = 0.71 wt%

Mix 1 Pred. (VGO 80% + WCO 20%)

Mix 3 Pred. (VGO 80% + WLO 10% + WCO 10%) Mix 1 act. (VGO 80% + WCO 20%) Mix 3 act. (VGO 80% + WLO 10% + WCO 10%) Mix 2 Pred. (VGO 80% + WLO 20%) Mix 4 Pred. (VGO 70% + WLO 20% + WCO 10%) Mix 2 act. (VGO 80% + WLO 20%) Mix 4 act. (VGO 70% + WLO 20% + WCO 10%)

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Temp. (˚C)

Figure 5 Predicted and actual diesel yield in weight per cent

adjustable in the built-in hydrocracker model used in the calibration step of this simulation case. The temperature profile of the distillation column is valuable for evaluating energy consumption and helping plant operation of cut point and process optimisation. So, it is difficult to adjust the simulation fractionation column to the actual number of stages, tray separation efficiency, pumparound rates, and temperature difference. The accurate predictions of product yields reflect the accuracy of the model in predicting product specifications. Specific gravity and boiling range are expressed as the most accurate predicted specs through simulation. Conclusion Aspen HYSYS V.11 is used to build a simulation case of an industrial hydrocracking unit utilising the same catalyst with the same reactor configuration as used in experimen - tal runs in our previous work.1 This case is a good prediction tool as it has a minor deviation from actual mass and heat balance and product specifications. Total reaction conver - sion values predicted by the simulation model of the 16 run cases show a good match between the simulation model and actual values, with a positive gap between the actual values in most cases. This gap increases with increasing WCO content in feed mixtures, ensuring the acidic nature of WCO increases

catalyst cracking activity and hence increases reaction conversion under the same operating conditions of reac - tion temperature, hydrogen partial pressure, and LHSV. The software’s built-in fluid package (HCRSRK) to predict hydrocracking catalyst activity in the presence of WCO should be modified to match the actual resulting activity increased by the acid nature of WCO. Predicted values of gasoline and middle distillates (kero - sene yield + diesel yield) product yields from the simulation case show good matching with actual values from the exper - imental test run. On the other hand, kerosene and diesel pre - dicted individual values do not match experimental test run values that reflect different cut points between experimental test runs and the fractionator built in the simulation case. On behalf of all authors, the corresponding author (m.sayed1989@ gmail.com) states that there is no conflict of interest. HYSYS V.11 is a mark of AspenTech. References 1 El-Sawy M S, Hanafi S A, Ashour F, Aboul-Fotouh T M, Co-hydroprocessing and hydrocracking of alternative feed mixture (vacuum gas oil/waste lubricating oil/waste cooking oil) with the aim of producing high quality fuels , Fuel , Vol 269, 2020, 117437. 2 Elshout R V, Bains C S, Moving up a tier – Part 2: Upgrading the bottom of the barrel. Hydrocarbon Processing , Vol 97, 2018, 312. 3 Bezergianni, Stella, Athanasios Dimitriadis, Temperature effect on

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Distillate yields wt% (Kerosene wt% + Diesel wt%)

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Mix 1 Pred. (VGO 80% + WCO 20%)

AAD = 0.07 wt%

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Temp. (˚C)

Figure 6 Predicted and actual middle distillate yield (kerosene yield + diesel yield) in weight per cent

PTQ Q4 2023