PTQ Q3 2022 Issue

recycling are firmly in a transition where companies keep resources in use, if possible, and then recover and regen - erate valuable products and materials at the end of life. Moreover, this transition is bringing forward challenges to balance emissions with circular plastics end-of-life goals. Low CAPEX optimisation strategies For too long, low-ranking CAPEX improvement proj - ects have led to antiquated control systems. With rapidly increasing energy costs affecting energy markets, refiner - ies and chemical plants are pursuing high-impact solutions based on first-principles methods (in-house or outside expertise) while also adapting enabling technologies from other industries, such as AI/ML, as discussed in the follow - ing summaries: Fired heater optimisation Hiding in plain sight, fired heaters are major emitters of GHGs in the hydrocarbon processing industry. Incomplete fuel gas combustion through furnaces and the use of excess air leads to higher toxic emissions. In addition, fuel quality variations and trying to increase production using ageing heaters and boilers can lead to a breakdown in control, safety, and thermal efficiency. From the crude distillation unit’s (CDU) furnace at the front-end of a refinery to world-scale furnaces seen in steam crackers, most fired heaters are designed for a thermal effi - ciency of 70-90%, whereas actual operating efficiencies are much lower. As the furnace ages, these challenges fur - ther exacerbate, leading to early replacement. While modern furnaces have electronics that gather data, there is minimal ability to perform real-time analytics and predict events in advance or provide predictive insights into interventions needed for optimal operation. According to

Avnish Kumar at LivNSense, even a 1% reduction in energy consumption from furnace operations will lead to reduction of millions of tons of atmospheric emissions (equivalent savings of $5 billion/per annum). Utilising existing assets The Calumet Specialty Products Partners L. P. $50 million renewable hydrogen project in Great Falls, Montana, USA, allows increased production of renewable diesel and further reduces carbon intensity. Utilisation of an existing hydro - cracker reduces CAPEX while still being able to produce 77 million gallons per year (mgpy). More importantly, once a renewable H 2 production unit and feedstock pretreatment unit are completed, total renewable diesel production is expected to reach 153 mgpy. Feedstock pretreatment units play a crucial role in squeezing out significantly higher volumes of renewable diesel from a hydrocracker. Similarly, existing hydrocrackers at US and European refineries can be upgraded to process biomass-based feeds. However, hydrogen deficits from higher hydrocracking and hydrotreating run-rates continue to be a concern. As one of the major consumers of hydrogen, refineries have received the mandate to reduce the carbon footprint of hydrogen production, such as from SMR units, by using green hydrogen. However, while green hydrogen is picking up momentum, refuse-derived fuel (RDF) to hydrogen via the syngas route can be one of the prominent solutions for reducing the hydrogen carbon footprint. According to Dattesh Kondekar at Technip Energies India Ltd, “the RDF gasification method not only can solve environmental problems of waste accumulation but also support refineries to use net-zero-carbon hydrogen con - tributing to the reduction in net CO₂ emissions.” Kondekar also noted that RDF is relatively faster to implement and can use part of the existing refinery hydrogen plant infra - structure for syngas processing and hydrogen purification. High-value outlets Waste plastics recycling Of the 7.0 billion tonnes of post-consumer plastic waste generated globally so far, less than 10% has been recycled. Going forward, certain refiners are introducing liquefied waste plastic as a new and sustainable feedstock. For example, Neste Oyj is working towards replacing crude oil feedstock with over 2 million tons of alternative renewable and recycled raw materials at its refineries by 2030, with liquefied waste plastic accounting for over 1 million tons of this annually. FCC and hydroprocessing units make them appropri - ate for waste plastics and end-of-life tyre processing. 2 For example, polyolefinic plastics (see Figure 1 ), the waxes obtained in their fast pyrolysis, and the tyre pyrolysis oils can be co-fed together with the current streams from the facility’s various catalytic conversion and thermal conver - sion units. 3 This co-feeding or co-processing strategy will form the basis for industrial-scale consolidation of hydrocarbon pro - cessing with recycling of society’s wastes (such as plastics

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Styrene

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Polystyrene

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Figure 1 Styrene and polystyrene polymer molecules

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PTQ Q3 2022

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