PTQ Q4 2022 Issue

Exelus, is developing a versatile bi-functional hydrocrack- ing catalyst ExPURT, to make this transformation possible. A Ioan-Teodor Trotus, Segment Lead Hydroprocessing, Custom R&D Solutions, hte GmbH, ioan-teodor.trotus@ hte-company.de: Pyrolysis of plastic waste to produce a liquid pyrolysis oil requires relatively mild conditions for the pyrolysis process itself, but further treatment is required to obtain a drop in feedstock for further processing in existing plants. Pyrolysis of plastic waste to produce a gas product requires much more energy for the pyrolysis process. Syngas, olefins, dienes, or acetylene could be components of interest in the pyrolysis gas. Further purification processes for these gases would be less complicated and probably less energy intense than the purification processes required for liquid pyrolysis oils. Whether one or the other is better depends a lot on regional factors such as the availability of cheap and abun- dant energy and the types and amounts of plastic waste available. Both liquid pyrolysis oil upgrading and syngas conversion to petrochemicals and intermediates are cur- rently hot areas for research and development where hte offers both equipment for catalyst testing and R&D ser- vices such as catalyst testing campaigns. In the end, just like there is not one single refinery con - figuration that beats all other options, we will probably see multiple technologies emerging, depending on location, for the chemical recycling of plastic waste. A Matthew Stephens, Senior Manager of Economic Engineering, Imubit, matthew.stephens@imubit.com: When considering the full slate of products from plastics waste pyrolysis, such as ethylene and propylene, which can be recovered and made into virgin polymers again, it really does not seem like that bad of an option. Gasification is likely a much better starting point for chemicals like metha- nol or liquid fuels, but it might actually be a poor route to traditional pyrolysis-based petrochemical feedstocks like ethylene and propylene. Additionally, it is less of a drop-in technology like pyrolysis that could be bolted onto an exist- ing olefins unit. A Ghoncheh Rasouli, Product Management Consultant, KBC (A Yokogawa Company), Ghoncheh.Rasouli@kbc. global: Recycling chemical plastics drives sustainability and decar- bonisation. Additionally, it decreases waste and pollution, reduces the consumption of limited natural resources, such as oil, and leads to the production of synthetic feedstock. For plastics to be completely recycled, chemical recy- cling technologies must be developed to achieve the com- plete recycling of plastics. While the gasification of plastic waste aims to recycle or reuse plastic waste by convert- ing it into valuable gases, it does not provide the required light/heavy hydrocarbon feed for petrochemical plants and refineries. Pyrolysis-based technology, however, recycles synthetic light- and heavy-hydrocarbon feedstock to the petrochemical plant and refinery. This results in high-end

quality products while reducing the need for further upgrade downstream. In addition, plastic pyrolysis technology decreases waste production during polymer production and reduces oil usage, NOx and SOx emissions, and landfill waste. Plastic pyrolysis is an excellent technology for managing plastic waste and mitigating ecological risks, but it can be com- plex. To reduce this complexity, process simulation and optimisation software can be used to model the kinetic reaction network, calibrate the model, observe and analyse the effect of different feedstocks and operate conditions on KPIs while increasing yield and thermal efficiency. Pyrolysis can evolve with the development of the follow- ing two new technologies where plastic waste could be converted to potential feedstock: Catalytic pyrolysis Using a catalyst reduces cracking temperature and energy consumption to convert plastic waste into fuel and other commodities. Advantages include improved efficiency and product selectivity, which results in high-end quality products, reducing the need for further upgrade downstream. This method could save 3.5 billion barrels of oil from polymer production and save nearly USD 40 million annually. Thermal pyrolysis Uses energy provided by electrical jacket, green hydrogen as a fuel, and hydrocarbon-based fuel consumption with optimised combustion to not only reduce emissions but also increase combustion efficiency and carbon capture. This oil can be blended with diesel to be used in engines. Although the process produces cor- rosive hydrochloric acid, it can be avoided by adding an absorber. A Francis Tsang, Director, Plastics Recycling Technology (Hydo-PRT), KBR, francis.tsang@kbr.com: Waste plastics to BTX is a challenging route, whether that is via pyrolysis or gasification. Most pyrolysis and hydro - thermal liquefaction processes focus on waste plastic to oils as opposed to aromatics. The price premium of the renewable BTX product against renewable oils is often offset by additional costs, complexity, and lack of scale in current recycling technology. A disadvantage of non-gasification recycling technologies is that feedstock to these processes does require a more complex feed preparation step for refuse-derived fuel (RDF), unless extremely high in plastic content, with a high level of pre-sorting if not an ideal feed. This can be addressed at the collection and sorting stage by the implementation of additional equipment to prepare a more suitable, high plastic content feed, which, of course, comes with a cost. However, gasification has its own challenges in process - ing plastic-rich RDF, including: • Capex intensive – modularisation/small-scale design is rare • Multistep process – waste-to-syngas, syngas cleaning, syngas-to-methanol (catalytic), methanol to BTX (catalytic) • Low relative yields • Substantial GHG/CO₂ formed as a side-product • Dioxins and furans emissions • High total costs and high complexity.

PTQ Q4 2022