PTQ Q2 2023 Issue

as shown in Table 2. Analyses of distinction in produc- ing winter and summer grades shows low-temperature performance-improving additives appended to the winter grade. Figure 4 exposes an additional effect of MDFI and WASA or wax crystal modifiers. The main role of MDFI is to enhance the cold filter plugging point (CFPP) and pour point (PP) of diesel fuel, while WASA reduces the settling of n-paraffins during storage at low temperatures. The con - centration of MDFI from 100 ppm to 450 ppm and WASA in concentration from 120 ppm to 540 ppm in diesel fuel was tested. Every ppm of MDFI above 100 ppm increases the electri- cal conductivity of diesel fuel by 2.38 pS/m, while the slope of electrical conductivity increases with WASA concentra- tion from 120 ppm by 1.99 pS/m for every ppm of additive. Evaluation of different supplier WASAs for their conduc- tivity (as per ASTM D 2624) results in the conductivity meter going out of range. WASAs are polymeric materials (i.e., ethylene vinyl acetate co-polymers with high affinity to the solid dispersed phase in diesel fuel). SDA contains heteroatoms that are fuel-soluble chromium substances, containing polymeric sulphur and nitrogen compounds, and quaternary ammonium. It is possible that polymeric material, presented in WASA, could be a reason for faster static charge dissipation. Further, Figure 5 shows an induction zone (up to around 100 ppm of WASA), and the dependence on the electri - cal conductivity of diesel fuel increases with the increase of WASA concentration in this fuel. After this zone, every added ppm of WASA increases electrical conductivity by 3.7 pS/m. It means that winter grade ULSD, containing 120+ ppm of WASA, reveals no risk of fires or explosions caused by static electricity due to high electrical conductiv- ity higher than 150 pS/m. It is worthwhile to evaluate whether electrical conductiv- ity caused by the presence of WASA is sustainable with time. As is presented in Figure 6 , electrical conductivity due to 1.5 ppm SDA (b) decreases with time (500 h of stor - age) and is settled to levels at about 200 pS/m. The same performance is evident in Figure 6a for winter grade diesel containing WASA while not containing SDA. Electrical con- ductivity of the latter decreases to 210 pS/m for a period of 500 h of storage. WASA not only increases conductivity but can retain it for a prolonged time. Conclusion An SDA response of both summer and winter grade diesel fuels is evaluated at LNB. The response is more significant in the summer grade for the antagonistic effect of low-tem- perature-enhancing additives (MDFI and WASA). On the other hand, it was discovered that WASA could dissipate static charge at a concentration above 100 ppm. Winter grade low sulphur diesel fuel without dosing SDA and with 125 ppm WASA is safe (at electrical conductivity of 150 pS/m) to be stored and transported. References 1 Directive 2003/17/EC of the European Parliament and of the Council of 3 Mar 2003, Official Journal of the European Union , 22.3.2003.

2 Mochida, I., Choi, K-H., An overview of hydrodesulphurization and hydrodenitrogenation, Journal of the Japan Petroleum Institute , 47, (3), 145-163, 2004. 3 Hazrat, M. A., Rasul, M. G., Khan, M. M. K., Lubricity Improvement of the Ultra-low Sulphur Diesel Fuel with the Biodiesel, The 7th Interna - tional Conference on Applied Energy – ICAE2015, Energy Procedia 75, 111-117, 2015. 4 Groysman, A., Corrosion in Systems for Storage and Transportation of Petroleum Products and Biofuels , Springer Science+Business Media Dordrecht, 2014. 5 AmSpec Services, LLC, www.amspecgroup.com 6 EnviroFuels, LLC, Ultra-Low Sulphur Diesel: Operational Challenges Facing Engine Operators, Technical bulletin, Houston, TX 77002, 2007. 7 Guru, M., Karakaya, U., Altiparmak D., Alicilar A., Improvement of die - sel fuel properties by using additives, Energy Conversion and Manage - ment, 43, 1021-1025, 2002. 8 EN 590, Automotive fuels - Diesel - Requirements and test methods, European Committee for Standardization. 9 da Silva, J. I. S., Secchi A. R., An approach to optimize costs dur - ing ultra-low hydrodesulphurization of a blend consisting of different oil streams, Brazilian Journal of Chemical Engineering, Vol. 35, No. 04, 1293-1304, Oct-Dec 2018. 10 Ferreira, A. S., Nicoletti, M. C., Bertini, J. R., Giordano, R. C., Method - ology for inferring kinetic parameters of diesel oil HDS reactions based on scarce experimental data, Computers and Chemical Engineering, 48, 58-73, 2013. http://doi.org/10.1021/ acs.energyfuels.5b00467 Rosen Dinkov is a Deputy Chief Process Engineer at LUKOIL Neftohim Burgas, Bulgaria (LNB). He holds a PhD from University of Chemical Technology and Metallurgy, Sofia, Bulgaria. He is an author of more than 70 papers and has over 500 citations. His research interests are focused on crude oil characterisation, bio/conventional fuels blends and bitumen characterisation and modelling of refinery distillation processes. Ivo Andreev is Senior Process Engineer at LNB. He has professional experience in fuel quality monitoring and new grades of fuel formula- tion. He holds a Masters in chemistry from the University of Chemical Technology, Burgas, Bulgaria. Dicho Stratiev is Chief Process Engineer at LNB. He holds PhD and DSc degrees and is an author of 255 papers, two books and has 1200 citations. He is also a Professor at the Institute of Biophysics and Bio - medical Engineering, Bulgarian Academy of Sciences. Ilian Kolev is Senior Process Engineer at LNB. He holds a Masters in chemistry from the University of Chemical Technology, Burgas, Bulgaria. He has co-authored more than five papers and his research area is hy - drocracking of vacuum residues and hydrodesulphurisation processes. Miroslav Atanasov is Senior Process Engineer at the Zeeland Refinery, the Netherlands. He holds a Masters in chemistry from the University of Chemical Technology, Burgas, Bulgaria. His professional competen - cies are in the field of catalytic refinery processes such as hydrodesul - phurisation of both gasoline and diesel fractions. Katarzyna Grabowska is an Area Sales Manager for Poland & the Bal - tics at Veolia Water Technologies & Solutions with seven years’ ex - perience in technical sales towards refineries. She holds a Masters in biotechnology from the University in Poznan. Cobbin Mackenzie is a Fuels Technical Sales Chemist from Infineum UK with four years’ experience offering technical services to customers across the CEE region, working closely with their distributer, Brenntag. He holds a Masters in chemistry from the University of Bristol.

PTQ Q2 2023