Ebullated bed reactors are suitable for deeply converting heavy feedstocks such as residues. In this study, a dynamic reactor model is developed taking into. These are the proprietary H-Oil and LC-Fining processes.1,2 Both of these are based upon ebullated-bed reactors, which allow catalyst addition/withdrawal and . Ebullated-bed residue hydrocracking is a well-proven technology that creates value from the process. Sediment often causes severe fouling of the reactor.
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Discover why residue upgrading through the application of ebullated-bed hydrocracking is a well-established, commercially proven technology due to the improved crude flexibility now achievable. The appetite for residue upgrading through the application of ebullated-bed hydrocracking is growing around the world, as ebullaetd is a well-established, commercially proven technology offering very high conversion levels and can help, therefore, to minimise the amount of bottoms sent to the bunker fuel pool.
Moreover, the rexctor of ebullated-bed hydrocracking as a technology solution for refiners has been enhanced by the recent trend for greater vacuum residue VR feed processing flexibility, which leads to improved refinery crude diversification economics.
Since ebullated-bed hydrocracking was commercialised in the s, 16 units have been built. In the last four years, its popularity has increased significantly; another six units are planned to be online by This shift is due to both proven design upgrades and the improved crude flexibility now achievable.
Ebullated-bed residue hydrocracking
The first-generation units operated on crude slates very much in line with design and focused mainly on hydrodesulphurisation. In the s, unit operation shifted towards higher bottoms conversion and with it came the advent of the sediment foulant control era. Higher levels of sediment are formed at higher conversion levels owing to greater destabilisation of the VR feed matrix known as SARA saturates, aromatics, resins and asphaltenes.
Unit cycle lengths were thus exclusively determined by the degree of sediment-induced fouling of key downstream hardware such as separators, heaters, fractionators and exchangers. This cycle-limiting phenomenon thus constrained the feed processing flexibility of the units when high bottoms conversion was the key operational objective. Now, however, the state of the art is such that many units are successfully operating with a variable crude diet while maintaining a high on-stream factor.
Furthermore, the current lower price crude market environment is providing the opportunity for more ebullated-bed unit operators to process VR feeds derived from a crude blend featuring the design crude as the major component and one or two other compatible crudes as minor components. In some cases, this has provided higher conversion performance through the net lower sediment formation tendency of the blended crude.
US9738839B1 – Generation ebullated-bed reactor system – Google Patents
This requires proper management of crude changes, effective unit monitoring and application of best practices, but it can be a key profit-generating opportunity. This operator recently successfully increased the unit cycle length from one to two years in an operation where the crude slate changes every two to three days.
The catalyst employed plays a key role in maximising unit on-stream factor, as it is the first line of defence in controlling sediment. For instance, it has commercialised the TEX series of catalysts that exhibits better sediment control combined with higher conversion activity for processing VR feeds derived from Middle Eastern crudes. As fresh catalyst is added on a daily basis, it can also be viewed as a process variable whereby higher amounts of catalysts are added when processing higher-sediment-forming feeds or when operating at higher bottoms conversion levels.
It is advisable for operators considering adjusting their operating window to work closely in the early stages with the unit licensor and the catalyst provider.
Changing the feed changes the SARA matrix, which can lead to cycle-limiting fouling. Both the licensors and the catalyst providers reactir commercial and pilot plant data that enable them to rank the fouling behaviour of feeds derived from different crudes accurately.
USB1 – Generation ebullated-bed reactor system – Google Patents
Criterion draws on its large database in order to advise on which crudes refiners could blend in and which they should avoid. These data are also key inputs for its SEDEX model, which predicts the change in sediment level as a function of crude type or when blending crudes. Changing other parameters, such as conversion, throughput or temperature, can also lead to enhanced rates of fouling.
But, again, by working with the licensor and the catalyst supplier, substantial manoeuvrability can often be unlocked to optimise unit performance in a balanced fashion. Earlier-generation designs were more closely integrated with downstream fluidised catalytic cracking units and the key products required further upgrading to meet the required specifications.
Ebullated bed reactor – Wikipedia
In contrast, the design of newer-generation units features an integrated hydrocracker—high-pressure hydrotreater in the same high-pressure loop. This enables direct production of high-value transportation fuels such as ultra-low-sulphur diesel from VR.
Shell currently operates both types of ebullated-bed reactof licensed technologies: InCriterion became the first company to introduce an ebullated-bed residue hydrocracking catalyst specifically developed to control sediment formation. Since then, Criterion has made significant advances and commercialised a series of catalysts that exhibit better sediment control and show higher conversion activity.
Figure 1 shows the development of the TEX series of catalysts, which have been customised primarily for processing VR feeds from Middle Eastern crudes. These have proved to be very effective in upgrading notoriously difficult feeds, including VR from Urals and Mayan crude oils, and in the conversion of bitumen to synthetic crudes. Criterion uses what it calls the 4Cs approach to residue upgrading, which helps to provide the inherent robustness required when the operation moves away from design, such as in the case of varying the crude slate.
It is very important to be clear on the chemistry required: The reactpr of the feed is key, especially the nature and behaviour of the SARA matrix with conversion level. In addition, the operating conditions of the unit, including constraints, ebullahed a large bearing.
The graph shows how Criterion has commercialised the TEX series of catalysts that exhibits better sediment control combined with higher conversion activity for processing VR feeds derived from Middle Eastern crudes.
Residue gasification, especially in combination with SDA, offers a compelling investment opportunity for many refiners looking to adapt their assets due to the bunker fuels specifications. Discover how hydrocracker-ethylene cracker integration is proving to be an important differentiator for the competitiveness of refineries.
Technology Trends to watch — An Introduction. The bunker fuels challenge: How should you respond? Tuning the hydrocracker for lubricant base oils. Converting a residue desulphurisation unit to a DAO hydrocracker. Criterion is market leading in ebullated-bed catalysts, not least because of the advances made in the area of sediment control, as shown here for the TEX series of catalysts.
Accessible version of Figure 1. Key Takeaways Ebullated-bed hydrocracking offers high VR conversion levels and has seen a significant reactog in popularity based on upgraded designs. In the past, this long-established process was characterised by low crude flexibility, but the state of the art is now such ehullated many units are successfully operating with a variable crude diet while maintaining a high on-stream factor. Leveraging latest-generation customised catalysts and technology, operational and process experience, and best practices can also help refiners to adjust conversion or other parameters without incurring a significant cycle length penalty.
More in Industry Focus. Solvent deasphalting SDA — Residue Gasification Residue gasification, especially in combination with SDA, offers a compelling investment opportunity for many refiners looking to adapt their assets due to the bunker fuels specifications.
Hydrocracker—ethylene cracker integration Ebullaetd how hydrocracker-ethylene cracker integration is proving to be an important differentiator for the competitiveness of refineries. Technology Trends to watch — An Introduction The bunker fuels challenge: Tuning the hydrocracker for lubricant base oils Catalytic dewaxing Increasing crude ebhllated Converting a residue desulphurisation unit to a DAO hydrocracker Aromatic saturation technology Distillate mild hydrocracking.