Slurry Phase Hydroconversion Catalyst Recovery
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Solution Overview
Problem
Current hydroconversion processes for heavy feedstocks, such as heavy crude oils and bitumens, face challenges with catalyst deactivation, high coke formation, and inefficient product upgrading, particularly in fixed bed and ebullated bed technologies, while slurry phase technologies offer flexibility but require complex and costly catalyst recycling and produce significant residues.
Innovation Solution
A process combining hydroconversion with catalysts in slurry phase, distillation, and deasphalting, with an additional secondary post-treatment hydrogenation section to reduce the flushing stream's entity and recycle active catalysts, utilizing a deoiling step with solvents to separate solid and liquid fractions, allowing for selective recovery and recycling of catalysts like molybdenum, thereby enhancing product quality and reducing residue generation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If fixed bed or ebullated bed reactors with transition metal catalysts are used for hydroconversion, then catalyst activity and conversion performance are improved, but catalyst deactivation due to heteroatoms, metals, and asphaltenes causes operational issues and requires complex regeneration
Solution Approach 1:
The patent changes the physical state of the catalyst from fixed bed to dispersed slurry phase, and modifies operational parameters including using molybdenum or tungsten based catalysts with specific particle size distributions (0.1-10 micrometers). The catalyst is introduced as oil-soluble precursors that convert in-situ to active metal sulfides during reaction, operating at temperatures of 300-450°C and pressures of 30-200 atm with H2/S ratios of 100-1000 Nm3/m3
Solution Approach 2:
The patent employs disposable catalyst cartridges containing slurry phase catalysts that are replaced rather than regenerated. The catalysts operate effectively for a defined period and are then discarded with the flushing stream, eliminating complex regeneration operations while maintaining continuous production through simple cartridge replacement
2Adaptability or versatility
If slurry phase hydroconversion with dispersed catalysts is used, then flexibility for heavy feedstocks and conversion performance are improved, but catalyst recycling becomes complex and costly
Solution Approach 1:
The patent discards the catalyst with the flushing stream from the deasphalting unit and recovers it through a simplified filtration system. The spent catalyst is regenerated externally and returned to the reactor, or replaced with fresh catalyst cartridges, avoiding complex in-plant recycling operations while maintaining catalyst utilization
Solution Approach 2:
The patent segments the catalyst system into replaceable cartridges or discrete slurry batches that can be independently managed. This allows the catalyst to be separated from the main process stream and handled through dedicated filtration and regeneration units rather than integrating complexity into the main hydroconversion system
3Manufacturing precision
If high concentrations of active catalysts (thousands of ppm) are used for better product quality, then product upgrading is improved, but catalyst recovery and recycling becomes compulsory and costly
Solution Approach 1:
The catalyst performs its function at high concentration (1000-5000 ppm) during the reaction, then automatically separates with the heavy flushing stream during deasphalting. The system self-regulates catalyst concentration and distribution, with the catalyst naturally concentrating in the asphaltene-rich phase that is removed and processed separately through filtration
4Quantity of substance
If conventional catalyst separation methods (decanting, centrifugation, filtration) are used after hydrotreatment, then catalyst recovery is achieved, but the recovered catalyst has reduced activity requiring complex regeneration
Solution Approach 1:
The catalyst is pre-loaded into cartridges in a stable, non-active form (precursor compounds or protected sulfides) that prevents deactivation during storage and handling. The active form is generated in-situ just before use through thermal decomposition or reaction with H2S, ensuring maximum activity from the start of each operational cycle
5Ease of manufacture
If flushing stream from deasphalting plant is not treated, then process simplicity is maintained, but the flushing stream volume and contaminant load increase environmental and disposal issues
Solution Approach 1:
The patent introduces an intermediary treatment unit between the deasphalting plant and the hydroconversion reactor. This unit uses filtration or adsorption media to remove contaminants from the flushing stream while allowing the catalyst to pass through or be easily separated, transforming the harmful waste stream into a usable process material
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach significantly reduces the flushing stream's volume, upgrades the catalyst recycling process, and produces high-quality deasphalted oils with reduced contaminants, enabling more efficient conversion of heavy feedstocks into fuel oils and other refined products with minimal residue, suitable for catalytic cracking processes.
Implementation Method 1
the active form of the catalyst (generally the metal sulfide) is formed in-situ by thermal decomposition of the compound used, during the reaction itself or after suitable pretreatment
Implementation Method 2
The hydrogenating processes consist in treating the feedstock in the presence of hydrogen and suitable catalysts
Implementation Method 3
distillation and deasphalting
Data Source
AI summary
Process for the conversion of heavy feedstocks selected from heavy crude oils, distillation residues, heavy oils coming from catalytic treatment, thermal tars, oil sand bitumens, various kinds of coals and other high-boiling feedstocks of a hydrocarbon origin known as black oils, by the combined use of the following three process units: hydroconversion with catalysts in slurry phase (HT), distillation or flash (D), and deasphalting (SDA).