produced almost no CO 2 is the reason why its licensed process technology called HydroFlex does not include an amine unit in the high- pressure loop. The elimination of the amine unit from the process layout has many advantages, such as reduced Capex and Opex, lower carbon intensity (CI score), and decreased operating complexity. The effectiveness of these HDO and dewaxing catalysts has been demonstrated in more than 25 industrial units, and many of Topsoe- licensed units have used loads of its HDO and dewaxing catalysts. Introducing even minor amounts of biomaterial into a fossil diesel or kerosene hydrotreater requires a thorough understanding of the implications and strategies to mitigate potential risks. Co-processing renewable and fossil feedstocks introduces additional complexities. The hydrotreater must still convert all organic sulphur and nitrogen in the fossil portion of the feed to meet product specifications, while the HDO catalysts must convert all of the renewable feed. To achieve these multiple objectives, the HDO- graded bed catalysts are typically loaded on top of a NiMo fossil catalyst. The trick is to load the right amount of each type of catalyst so that the cycle length of the HDO catalyst matches that of the fossil NiMo catalyst while maintaining a stable pressure drop across all the catalysts. The ratio of the different types of catalysts is, of course, governed by the percentage of co- processing. It is also important to determine if a dewaxing catalyst is needed in the bottom of the reactor (below the fossil catalyst) to ensure that the mixture of fossil and renewable diesel still meets the required cloud point. Topsoe is experienced in designing the loading of a Choosing the right catalyst for co-processing co-processing unit to meet all product and cycle length objective and has more than 20 hydroprocessing units currently in operation in co-processing mode. Conclusion The production of renewable fuels represents a significant step forwards in the diversification of
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the global energy landscape. However, success depends on the development and deployment of advanced catalysts that can handle the unique challenges of renewable feedstock processing. Topsoe’s third-generation HDO catalyst, selective towards the hydrogenation route, and its specialised graded bed HDO catalysts are effective in both co-processing and standalone units. Figure 3 Phosphorous penetration in catalyst pellet of previous-generation P-trap compared to TK-3000 The catalyst and process technology not only ensure the production of high- quality renewable fuels but also enhance the profitability of the unit by increasing the product yield and extending the cycle length, thus improving the onstream performance. The enhanced capacity for picking up contaminants, including phosphorus, helps the refiner process lower-quality renewable feedstocks to further enhance the profitability of the operation. As the industry continues to evolve, the role of catalysts in enabling the energy future cannot be overstated. “ Success in the production of renewable fuels depends on the development and deployment of advanced catalysts that can handle the unique challenges of renewable feedstock processing ”
Henrik Rasmussen HWR@topsoe.com
www.decarbonisationtechnology.com
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