PTQ Q2 2026 Issue

reducing unplanned shutdowns, especially with variable crudes. In the CDU stripper overhead, the closed-loop sys- tem self-washes with condensed water and fresh stripping zone vapour, preventing salt accumulation in the rectifica - tion wash zone. This reduces NaCl decomposition into HCl at higher temperatures, further mitigating CDU top section corrosion. Economic impact The $2.37 million savings include $2.05 million from utility reductions and $0.32 million from Capex savings in green- field designs due to smaller column diameters and efficient ejectors (see Table 6 ). This translates to a payback period of less than two years for retrofit investments, remaining robust despite utility price fluctuations. Retrofit feasibility and implementation The retrofit-friendly design required minimal modifications, including chimney tray blanking and nozzle additions, implementable during 30-45-day shutdowns. The design’s flexibility to increase throughput by 5-10% offers addi - tional revenue, particularly for processing high-contami- nant crudes. Strategic implications This configuration positions refineries to meet net-zero targets while enhancing profitability. As a licensable tech - nology, it offers a strategic advantage, aligning with environ- mental, social, and governance (ESG) criteria that influence market competitiveness. The design’s adaptability to evolv- ing crude slates and regulatory frameworks ensures long- term relevance, potentially attracting technology-driven refiners seeking sustainable solutions. Conclusion By prioritising heat recovery and fouling mitigation, this grassroots CDU-VDU innovation achieves 40% steam reduction and 16% power reduction. This translates to an annual $2.05 million reduction in Opex and a 52.9 million pounds reduction in CO₂ emissions per year in a typical 172,000 bopd Bombay High crude refinery. It offers a blueprint for eco-efficient new builds, with potential for increased throughput studies across opportunity crudes, while redefining distillation for a net-zero era. Through vapour load recovery, wash recirculation, and dry recti- fication, it boosts yields by 2-3%, improves reliability by 20-30%, and increases flexibility. As refiners build new units, this configuration delivers profitability and sustain - ability, thereby enhancing performance and operational excellence. In today’s landscape of geopolitical crude vol- atility and carbon pricing mechanisms, such innovations are essential for maintaining competitive margins while advancing decarbonisation agendas. Further reading 1 A. Szklo, R. Schaeffer, Fuel specification, energy consumption and CO₂ emission in oil refineries, Energy , 32 (2007) pp. 1,075-1,092. 2 M.J. Bagajewicz, Design of crude fractionation units with preflashing or prefractionation: energy targeting, Ind. Eng. Chem. Res. , 41 (2002) pp. 3,003-3,011.

Total savings (Capex and Opex)

Parameters Opex savings

Savings, million $

2.05 0.32 2.37

Capex difference

Total savings

Table 6

3 M.A. Waheed, A.O. Oni, Performance improvement of a crude oil dis - tillation unit, Appl. Therm. Eng. , 75 (2015) pp. 315-324. 4 Indian Patent Application No. 202311020036, A Distillation System for Separating Components of Crude Oil, Engineers India Limited, 2023. 5 S. Golden, T. Barletta, S. White, Designing the CDU/VDU for oppor - tunity crudes , Sour & Heavy (2012). 6 M.A. Fahim, T.A. Al-Sahhaf, A. Elkilani, Fundamentals of Petroleum Refining , Elsevier, 2009, p. 513. 7 C.S. Hsu, P.R. Robinson, Springer Handbook of Petroleum Technology , Springer, 2017, p. 1182. 8 J.H. Gary, G.E. Handwerk, M.J. Kaiser, Petroleum Refining: Technology and Economics , 5th ed., CRC Press, Boca Raton, 2007, p. 488. 9 S. Kumar, N.S. Madhusudan, M.O. Garg, Method for increasing gas oil yield and energy efficiency in crude oil distillation, US Patent 9,546,324 B2, 2017. 10 P.R. Pradeep, S.K. Das, T.H.V.D. Prasad, A.K. Kumar, R. Rajesh, M.P.K. Kumar, D. Bhattacharyya, S.K. Mazumdar, S.S.V. Ramakumar, Process for conversion of high acidic crude oils, US Patent Application 2019/0225892 A1, 2019. Ramanayya Gorle is a Senior Manager at Engineers India Limited (EIL), New Delhi, with more than 15 years of experience in process design, development, and commissioning for the oil and gas and refining sec - tors. His expertise spans mass transfer equipment, column hydrau - lics, desalters, heat exchangers, fired heaters, and heater treaters. He is credited with more than 15 patent applications and is a Certified Energy Manager and Auditor. Gorle holds a BTech in chemical engi - neering from Andhra University. Grandhi Srivardhan is an Assistant General Manager in R&D at EIL, New Delhi, with more than 15 years of experience in computational fluid dynamics, coal-to-liquids, refinery and petrochemical technology development, and energy efficiency improvement. He is credited with more than 20 patent applications, of which 10 have been granted, along with three international publications. Srivardhan holds a post- graduate degree in chemical engineering from IIT Kanpur. Narendra Kumar Paladugu is Assistant General Manager, R&D, at EIL. His expertise spans process simulation, in-house software develop- ment, coal gasification, and renewable energy systems. He has been actively involved in the development and deployment of indigenous process tools and technologies, contributing to both conventional hydrocarbon processing and emerging energy transition domains. Paladugu holds a Master of Technology in chemical engineering from NIT Tiruchirappalli. Anil Kumar is the Executive Director (Technical) at EIL, New Delhi, with more than 31 years of experience in process design, technology development, and plant commissioning across the oil and gas, refining, and petrochemical sectors. His expertise spans crude oil distillation, hydrotreating, hydrocracking, and complex refinery configurations, with particular strength in refinery configuration studies and LP-based optimisation modelling to evaluate feedstock flexibility, product slate optimisation, and energy efficiency. Kumar holds a BTech in chemical Engineering from Banaras Hindu University.

PTQ Q2 2026