Hydroprocessing and Hydrocracking – Kunlun Consulting

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Hydroprocessing and hydrocracking are key technologies for producing clean fuels, enabling refineries to have relatively flexible processing capabilities while meeting increasingly stringent fuel quality requirements. In recent years, hydrotreatment and hydrocracking technologies have played an important role in helping refineries improve their processing efficiency, and they have continued to mature as they develop. 1) Hydroprocessing technology for conventional crude oil: This technology is already highly mature at the process level. The focus of research and development in this area lies in developing new process schemes to improve reaction efficiency, as well as designing new reactor internals to enable catalysts to exhibit higher activity ； Since many process technologies are relatively mature, catalyst innovation determines the development prospects of hydroprocessing of conventional crude oils. Among the hydrogenation processes that are currently in industrial use, (1) the processes that are widely applied include Albemarle’s UD-HDS (ultra-deep hydrodesulfurization) process, which uses distillate oil as raw material ； Axens’ Prime-G+ (selective hydrodesulfurization) process using naphtha as a raw material ； Axens’ Prime-D process using diesel as a raw material ； EMRE/KBR’s HYDROFINING process ； The MQD Unionfining process (2) developed by UOP, which uses VGO and distillates as raw materials, is a process that enables the production of ULSD while also ensuring that the levels of nitrogen, density, aromatics, and cetane number meet the specified requirements; processes of this type include Albemarle’s UD-HDS and HDAr ； Axens’ Prime-D ； SINOPEC’s FHI and SSHT ； Haldor Topsøe uses conventional hydrogenation processes with NiMo catalysts as well as HDS/HDA processes ； REDAR from Shaw/BASF and MQD Unionfining from UOP, among others. (3) Dewaxing processes that can improve the low-temperature flowability of diesel include: Albemarle’s CFI, EMRE/KBR’s MIDW, Haldor Topsøe’s diesel dewaxing process, MOL of Hungary’s MOLDew, UOP’s Unicracking/DW, and SINOPEC’s FDW, among others. (4) Processes that can reduce hydrogen consumption include DuPont’s IsoTherming process, in which the feed oil is saturated with hydrogen before being fed into the reactor; as well as SK Company’s HDS pretreatment process. For feed oils containing LCO or CGO, the hydrogen-consuming compounds are removed from them prior to hydroprocessing ； Axens’ Prime-G+, EMRE’s SCANfining, and UOP’s Selectfining processes. Regarding catalysts, the hydrogenation catalysts for conventional crude oils that are already in industrial use can be roughly divided into the following categories: naphtha/distillate/wax oil hydrogenation catalysts ； FCC gasoline selective hydrodesulfurization catalyst ； FCC pretreatment catalyst that eliminates the need for gasoline after-treatment ； Hydrocracking pretreatment catalyst ； Catalyst for hydrogenation of heavier feedstocks ； Diesel dewaxing catalyst ； protectant ； 2) Hydrocracking of conventional crude oil – Currently, hydrocracking units have a greater capacity to process low-quality feedstocks than before, and they can produce more diesel that meets specifications closer to those of the final product. In contrast, the products obtained from catalytic cracking require further upgrading in order to meet the increasingly stringent diesel quality standards. Therefore, the hydrocracking process is gradually becoming a superior conversion method compared to the catalytic cracking process. In industrially applied hydrocracking processes: (1) single-stage circulation and two-stage circulation are the most widely used hydrocracking process configurations. The selectivity and reactivity of the two-stage cycle scheme are both superior to those of the single-stage cycle scheme. Generally speaking, two-stage cycles are more suitable for large hydrocracking units aimed at achieving complete conversion, and they are capable of processing high-nitrogen feedstocks ； The single-stage unit is the preferred choice for refineries with limited investment costs. (2) A hydrocracking scheme that can operate under milder conditions (such as lower pressure, temperature, and hydrogen consumption); compared to conventional single-stage cyclic hydrocracking schemes, this approach can achieve the same or even higher yields of distillate oil at lower pressure, catalyst temperature, and hydrogen consumption. (3) The partially converted hydrocracking processes that can enhance the flexibility of hydrogenation operations in refineries include: Chevron Lummus Global’s Optimized Partial Conversion (OPC) process and Selective Staging process, as well as Haldor Topsøe’s Segmented Partial Conversion (SPC) process ； UOP’s advanced partial conversion Unicracking (APCU) process ； (4) Hydrocracking process capable of effectively reducing hydrogen consumption ； (5) Hydrocracking technology capable of modifying LCO into a component usable in diesel blending. Regarding hydrocracking catalysts, those that have been put into industrial use typically involve active metals supported on acidic carriers. Metals are mostly composed of Pt, Pd, Ni, Mo, Co, W, etc.; in some catalysts, organic additives (such as B, P, or Si) are also included to enhance activity and selectivity ； The carrier can be a molecular sieve and/or an amorphous material; catalysts using molecular sieves as carriers are suitable for hydrocracking to produce gasoline, while those using amorphous materials as carriers are better suited for producing diesel. 3) Residue hydroprocessing technology: As crude oils become increasingly heavy and the demand for high-value products rises, refineries face the challenge of maintaining profitability in a changing market environment. Hydroprocessing of residue is one of the best industrial methods currently used by refineries to transform such feedstocks into high-quality, high-value products. It enables the conversion of these feedstocks along with HDM, HDN, HDS, as well as the removal of Conradson residue and asphaltenes. Compared to conventional hydroprocessing techniques, hydroprocessing of residue operates at higher temperatures and pressures, which results in increased capital costs and operating expenses for the facilities. The progress in residue hydroprocessing technology is mainly reflected in processes, catalysts, and reactor design. In terms of processes, the industrially established hydroprocessing processes for residue oil mainly include: Axens’ Hyvahl process ； The RDS/VRDS process of Chevron Lummus Global ； ExxonMobil’s Residfining process ； SROH residue hydrodesulfurization process by Shell Global Solutions ； UOP’s RCD Unionfining process ； Regarding catalysts, those used in industry are obtained by loading oxides of Co, Mo, Ni, or W on Al2O3, SiO2, or SiO2/Al2O3 carriers. To achieve the desired conversion rate and meet the requirements of the target product, it is necessary to optimize the catalyst’s activity, particle size, pore size and pore distribution, selectivity, and shape. Companies that can supply catalysts for the hydroprocessing of industrial residue oil include Catalysts and Chemicals Industries, Criterion Catalysts & Technologies, Haldor Topsøe, and Sinopec. Regarding reactors, the hydrodesulfurization of residue oil can be carried out using four types of reactors: fixed-bed, fluidized-bed, moving-bed, and slurry-bed reactors; the choice depends mainly on the properties of the feed oil and the desired product characteristics. Some processes employ combined reactor systems (such as fixed-bed + moving-bed) to optimize the processing procedure. Some processes help prevent premature deactivation of the HDS catalysts downstream by installing a protection bed reactor upstream of the HDS reactor to remove most of the metals and asphaltenes from the residue oil. 4) Sludge oil hydrocracking technology: Many regions around the world possess large reserves of unconventional, heavy crude oils, and sludge oil hydrocracking technology will play an important role in converting these feedstocks into high-value products. The residue hydrocracking process can be used to provide suitable FCC feedstock (for gasoline production) as well as high-quality ultra-low sulfur diesel. The reactors used in the industrialized residue hydrocracking process are fixed-bed or fluidized-bed reactors. The typical fixed-bed process is the HYCON residue hydrocracking process developed by Shell Global Solutions. Because fresh catalyst can be added and spent catalyst can be removed at any time, fluidized bed reactors can process feed oils with high metal contents. A typical fluidized-bed residue hydrocracking process includes: (1) Axens’ H-Oil ； (2) CLG’s LC-FINING and LC-MAX processes ； (3) Headwaters Company’s HCAT process ； (4) THE STRONG PROCESS DEVELOPED IN COLLABORATION BY SINOPEC Fuyan Research Institute AND Luoyang Research Institute ； The biggest common drawback of both fixed-bed and fluidized-bed technologies is the decrease in residue stability at high conversion rates, which limits the highest achievable conversion levels. Therefore, the development of a new residue hydrocracking technology using a slurry bed has been a key focus in this industry in recent years. However, the slurry bed hydrocracking process has not yet been industrialized. The main processes include: (1) BP/KBR’s VCC ； (2) Eni’s EST ； (3) PDVSA’s HDHPLUS ； (4) UOP Company Uniflex ； (5) The RMD process of SINOPEC Research Institute of Petroleum.