maintaining continuous production and meeting customer demands. Significant demetalisation of the feed to the hydro - cracker using MagAFS is seen in commercial operations on naphtha (light coal tar). This process has successfully demonstrated the removal of up to 98% total solids and 60-100% various metals in the feed steam, as shown in Table 1 . Although vanadium is not shown in the tested liquid stream, the mass susceptibility (magnetising characteristic) of V₂O₃ (1,976 x 10 -6 c.g.s. unit) is much higher than that of NiO (600 x 10 -6 c.g.s. unit). Therefore, V₂O₃ is easier than NiO to be removed by MagAFS. In conclusion, the implementation of a well-designed graded bed system using AFS and MagAFS technolo - gies is vital for enhancing the flexibility of hydrocracker operations. By ensuring optimal catalyst performance and facilitating quick adjustments in production outputs, these systems empower refiners to confidently navigate the com - plexities of the market effectively. The commercial perfor - mance results underscore the tangible benefits of these technologies, demonstrating that refiners can achieve lon - ger run lengths, lower pressure drops, and improved profit - ability. As industry continues to evolve, the importance of such innovative solutions will only grow, positioning refin - ers to meet both economic and environmental challenges head-on. Q How can the FCC unit be upgraded to benefit petro - chemical integration? A Delphine Le-Bars, Vice President Deep Conversion & Upgrading Product Line, Delphine.le-bars@axensgroup. com, Axens The FCC unit can be upgraded to benefit petrochemical integration through strategies ranging from some that can be easily applied to the existing FCC units to modifica - tions involving the implementation of new satellite units. An example of easy and quick implementation could be increasing severity and/or using specific catalyst formula - tions and additives (like ZSM-5 zeolite) with high selectivity to olefins. Other possibilities when evaluating unit modifi - cations to maximise olefins production include: • Incorporation of a separated riser (Petroriser) for light naphtha cracking recycling at a higher temperature (oper - ating under more severe conditions) than the main riser to maximise propylene production. • Integration of FlexEne technology, an innovative combi - nation of FCC and oligomerisation technologies, to expand the capabilities of the FCC process towards maximising olefins production. This flexibility is achieved by the oligo - merisation of light FCC alkenes (olefins) and recycling oligomerate for selective cracking in the FCC unit. The FlexEne concept can be easily implemented in existing FCC units. Investment in new FCC technologies, such as HS-FCC (high severity fluid catalytic cracking) technology, is an excellent prospect for olefins maximisation. The HS-FCC unit is an evolution of the well-known FCC process to reach
a considerably higher level of light olefins production, in particular propylene, to bridge the gap between refining and petrochemicals industries. Petroriser, FlexEne, and HS-FCC are marks of Axens. A Mark Schmalfeld, Global Marketing Manager, mark. schmalfeld@basf.com, Hernando Salgado, Technical Service Manager IMEA, hernando.salgado@basf.com, BASF Refinery Catalysts Upgrading the FCC unit can significantly enhance the inte - gration of petrochemical processes within refineries. The unit primarily converts heavy petroleum feedstocks into lighter, more valuable products like gasoline and diesel. However, by implementing specific upgrades, refineries can optimise the FCC unit to produce higher yields of pet - rochemical feedstocks, thus improving overall operational efficiency and profitability. Choosing advanced catalysts that are more selective towards lighter olefins, such as propylene and ethylene, can significantly increase the output of petrochemical pre - cursors. Some modern catalysts also have enhanced stabil - ity and longer lifetimes, reducing the frequency of catalyst replacement and downtime. Modifying the FCC unit’s riser section allows for better catalyst distribution and contact time with the feedstock. A design that promotes turbulent flow can enhance cata - lyst effectiveness by improving the distribution of catalyst within the unit. Special bed riser terminations can also increase residence time to increase reaction severity. The implementation of a secondary or dedicated riser to crack recycled light naphtha also can play a fundamental role in maximising light olefins yield, especially in the range of ethylene and propylene under severe reaction conditions. Additionally, upgrading to advanced catalyst injection systems ensures uniform dispersion and optimal contact between feed and catalyst. Upgrades to injection systems can also be beneficial when using new advanced catalysts. Adjusting operating conditions such as temperature, pressure, and feedstock composition can help in maxi - mising desired olefins production. Increasing the sever - ity of the cracking process can lead to higher yields of lighter products but requires careful balancing to avoid excessive coke formation and catalyst deactivation. High- temperature equipment such as reactors and advanced separators may need to be changed to handle the desired operational conditions. One particular feature that allows high light olefins yield is the reduction of the hydrocar - bons partial pressure by increasing steam streams to the reaction environment. This facilitates the equilibrium con - ditions to increase the conversion of heavy hydrocarbons to light olefin molecules. In this regard, some units maxi - mising light olefins operate within the range of 10-20% steam-to-feed ratio. Installing high-temperature reactors or modifying exist - ing reactors to handle elevated temperatures safely can improve the cracking of heavier feedstocks. Utilising high- efficiency separators can better recover lighter products, minimising the loss of valuable olefins.
9
PTQ Q1 2025
www.digitalrefining.com
Powered by FlippingBook