as regulations change, driving producers and consumers to expect lower carbon footprints in their products. These changes cannot only improve profitability but also help refineries remain competitive in a rapidly evolving market. By addressing these factors, revamp projects can support the industry’s transition towards a more sustainable and diversified future. A Doug White, Principal Consultant, Emerson, doug. white@emerson.com Most revamp projects include a reduction in energy use and emissions as one of their goals. Typical investments include additions of renewable feedstocks if appropriate, increased use of renewable power and other fuels, process modifica - tions to increase energy efficiency, and closer monitoring of the process energy and emissions through better measure- ments and modelling of the process. A Harry Ha, Technical Fellow, Process Engineering, Energy and Chemicals, Fluor Canada Ltd., harry.ha@fluor.com The energy transition will have a big impact on revamp projects. First, a strategy for reducing the carbon footprint has to be considered for all new projects. Low-carbon feed- stocks or fuels are typically considered alternatives in the early stage of an engineering project. Using hydrogen as a fuel to heaters or electrification design of heaters is typi - cally considered in revamp projects. Options of using the amine unit to capture CO₂ or add - ing a selective catalytic reduction (SCR) unit to remove NOx from post-combustion flue gases are often listed in the scope to reduce the emissions. Renewable feed or product also plays a role in determining the scope of the projects. For example, vegetable oils are added into a hydrocracker feed slate for co-processing with conventional oil to make diesel in order to obtain the ‘credit’ for producing renewable diesels. Product diversification will affect the revamp project in a direct way. First, the process paths need to be defined for the specified products. More often, the selection of avail - able production technologies comes to play when scoping the revamp project. Storage of new products, tie-in con- nection with existing facilities, usage of utility supply, and safety impact on the existing flare system (assume it is to be utilised) all need to be carefully considered and evalu- ated for the project in order to identify the best economic and environmentally-friendly option. Q Can you highlight FCC unit cases where optimal mechanical operation was targeted and achieved? Mark Schmalfeld, Global Marketing Manager, Refining Catalyst, BASF, mark.schmalfeld@basf.com Optimal mechanical reliability in a fluid catalytic crack - ing (FCC) unit involves ensuring that all components and systems operate efficiently and consistently over time, minimising downtime and maintenance needs. Units are designed and operated differently, so the exact factors required to achieve optimal reliability may vary. However, key factors to consider include:
Robust design • Ensure feed nozzles are designed to withstand elevated temperatures and pressures and are easily maintained. Evaluate the system for erosion and make stepwise-based improvements. • Design cyclones to minimise erosion and plugging, ensur- ing efficient catalyst recovery. Cyclone erosion and plugging are common failure areas, predicating a focus on learn- ing about the specific failure mechanisms and developing improvements to extend the service life in the next operating cycle. Erosion mitigation • Use advanced materials and coatings to reduce erosion in critical areas like cyclones and risers. • It is possible to use computation flow simulations. Use computational fluid dynamics simulations to predict erosion patterns. Optimise design and make improvements in each turnaround. Temperature control • Monitor and control temperature profiles to avoid hot or cold spots that can affect reaction efficiency and catalyst life. Temperature control is also critical in the control of refractory curing, as this process improves its service life. • Implement advanced temperature sensors and control systems to maintain uniform temperatures. Fluidisation quality • Optimise fluidisation mode to enhance catalyst contact and reaction efficiency. Optimal fluidisation reduces risks of CO breakthrough, hot spots, and poor distribution in regen - erators, leading to uneven or weak temperature control. Distribution of solids through fluidisation to minimise wear and proper separation of solids and gas streams are critical to ensuring an extended operational run. Accurately model residence time distributions to optimise reaction kinetics and product yields. Maintenance and monitoring • Conduct regular health checks and simulations to anticipate and mitigate issues. Develop design or process improvement plans to implement in each turnaround to mitigate key concern areas. • Use predictive maintenance techniques to identify poten- tial failures before they occur. The literature has many specific examples of achieve - ments that increased FCC unit run length. Modelling, for example, has been used to identify and mitigate erosion in reactor cyclones. A simulation approach has been used to better understand an afterburn problem and mitigate the afterburn, which improved the reliable operation of the FCC unit. Evaluating an expansion joint to improve its design resulted in a longer run length for the unit. Similarly, work on slide value designs and improve - ments has resulted in improved run length. Additionally, developing predictive maintenance tools to understand the expected service life of components and preparing for replacement or design improvement in a turnaround can
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PTQ Q3 2025
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