Review of Global Refining Technologies

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A Review of Global Refining Technologies: After more than 150 years of development, global refining technologies have formed a comprehensive technical framework that can provide various crude oil processing solutions for over 600 refineries around the world. In recent years, global refining technology has seen continuous progress in areas such as expanding resources, reducing costs, improving cleanliness in production, and achieving intrinsic safety, particularly in the processing of heavy/poor-quality crude oils, the efficient conversion of vacuum residue, the integration of refining with chemical manufacturing, the production of clean fuels, and bioalternative fuels. 01 In terms of catalytic cracking, advancements in foreign catalytic cracking technologies have mainly focused on increasing the production of diesel and/or propylene, as well as on processing low-quality crude oils. Representative technologies include Shell’s MILOS process for simultaneous production of diesel and propylene, Axens’ PetroRiser process for high-propropylene output, UOP’s RxPro process for high-propropylene production, the HS-FCC process for high-propropylene yield developed by JX Nippon Oil & Energy and King Fahd University of Petroleum and Minerals in Saudi Arabia, KBR’s K-COT process for increasing propylene production using naphtha as a feedstock, and UOP’s CCU process for the catalytic upgrading of heavy crude oils and crude oils derived from asphalt. China has caught up in terms of catalytic cracking technology; a series of original and innovative catalytic technologies with significant impact, such as DCC (catalytic cracking) and MIP (catalytic cracking process for high-yield isoparaffins), which were developed independently by Sinopec, indicate that China’s catalytic cracking technology is now at the world’s leading level. 02 In terms of hydrogenation technology, UOP, Chevron, Shell, and Axens are currently the main suppliers of complete hydrocracking technologies. There are over 150 hydrocracking units worldwide that use UOP technology, and more than 100 units that utilize Chevron’s technology. In recent years, the main technical advancements in hydrocracking processes have included: 1) hydrocracking schemes that utilize liquid-phase continuous reaction zones, enabling higher single-pass conversion rates with a smaller reactor volume; 2) new adsorption processes that improve the quality of HVGO fed into hydrocracking units; 3) hydroprocessing/hydrocracking processes that allow for adjusting the severity of the hydroprocessing conditions in order to enhance the octane rating of ultra-low sulfur gasoline (ULSG) and the quality of ultra-low sulfur diesel (ULSD). Furthermore, the technology for catalytic hydrogenation of diesel (LC0) to produce high-quality gasoline and aromatics is attracting attention. UOP’s Unicracking technology and LCO-X technology are representative technologies in this field. The LTAG technology developed by SINOPEC’s Research Institute converts diesel into high-octane gasoline or aromatics through selective hydrogenation followed by selective catalytic cracking. It has already been approved by SINOPEC and is set to be implemented in more than 20 of its refineries. Under the current economic conditions in our country, it is of great economic significance to use this technology to reasonably reduce the ratio of firewood to gasoline. The focus of research and development in national designated residue hydrocracking technology is on how to extend the operational cycle of the plants and process lower-quality feedstocks. Typical fixed-bed hydrogenation process technologies mainly include the RDS/VRDS process, ResidHDS process, RCD Unibon process, Residfining process, etc. The technology for hydrotreating fluidized bed residue is gradually maturing; there are 22 residue fluidized bed hydrocracking units already in operation or under construction both domestically and internationally, which mainly employ the LC-Fining process and the H-Oil process. Slurry-bed residue hydrocracking processes are under development, with typical technologies including VCC, EST, HDHPLUS, Uniflex, and VRSH. The first industrial plant of this type was put into operation in 2013. To maximize the yield of light oil, combination processes for residue processing have developed rapidly, such as the solvent dewaxing-asphaltene removal (DAO) catalytic cracking-asphaltene removal (DOA) gasification combined process, and the residue hydrogenation-catalytic cracking two-way combined process (RICP). The lubricant hydrogenation processes mainly include ExxonMobil’s MSDW and MLDW processes, Chevron’s IDW process, BP’s BPCDW process, and Axens’ process from France. 03 In terms of catalytic reforming technology, UOP’s CCR process and Axens’ Octanizing process, as the two most competitive continuous catalytic reforming processes in the world, continue to be upgraded and improved. The counter-current bed continuous reforming technology developed independently by Sinopec has completed industrial trials with a capacity of 600,000 tons per year. Key performance indicators such as the yield of liquid products and hydrogen production are at an internationally advanced level; this also marks Sinopec as the third company in the world to possess original technology for continuous catalytic reforming. 04 In terms of coking technology, among the world’s existing coking units, delayed coking technology accounts for 78%, fluidized coking technology accounts for 8%, while flexible coking and other technologies account for 14%. The U.S.-based companies Conoco, Foster Wheeler/UOP, and Lummus, which are leaders in delayed coking technology, have developed combined processes that integrate delayed coking with other units, processes to increase the value of petroleum coke, as well as technologies for controlling the quality and structure of delayed coking petroleum coke. At the same time, they have improved the design of the feed systems for coking towers and coking heaters, thereby extending the operational cycle of these facilities. In recent years, as attention has grown to the pollution issues associated with coking units, ExxonMobil’s flexible coking technology, which was first put into industrial use in Japan in the 1970s, has begun to attract renewed interest from the industry. Over the past few decades, China’s refining industry has evolved from nothing to something, from a basic level to a high standard, and from a small scale to a large and powerful one. Through the joint efforts of several generations of petroleum professionals, China now possesses comprehensive expertise in all aspects of modern refining technology. It is capable of building refineries with a capacity of tens of millions of tons per year using its own technologies, and certain refining techniques, such as catalytic cracking, counter-current continuous reforming, selective hydrodesulfurization of catalytic cracking gasoline, and hydrodesulfurization of diesel, are among the best in the world!