PTQ Q4 2023 Issue

Feeds

Pretreat

Storage

Processing

Treating

Blending

Figure 1 Processing renewable feeds using hydroprocessing technology

A Giada Innocenti, Application and Project Manager, hte GmbH, giada.innocenti@hte-company.de, Ioan-Teodor Trotus, Team Leader Refining, hte GmbH, Ioan-Teodor. Trotus@hte-company.de The processing of a wider variety of crude feedstocks and, in general, the processing of more challenging feedstocks is going to be tackled by the existing refineries in most cases by utilising more efficient catalytic systems. The goal would be to repurpose the existing reactor technology to maxi- mise the yield of the target product. The real challenge that all the refineries will have to overcome is understanding how the feedstock behaves on the offered catalysts and/or in the pipelines and pump systems. As feedstocks become more challenging, models become less reliable, and it becomes more and more important for refineries to test the performance of the catalytic systems on the market in combination with real feedstocks. Testing is ideally performed on a smaller scale to mini- mise the costs associated. Testing will not only allow the best catalyst set to be selected but also uncover eventual issues in processing using a smaller amount of feed and develop solutions. Most often, hydroprocessing and FCC catalysts have been tested in separate experimental programs to optimise each one in isolation. However, with state-of-the-art test- ing equipment, one can also consider performing FCC pre - treatment and catalytic cracking experiments in tandem to evaluate the impact of pretreatment conditions on the FCC unit’s performance. This can also be employed to determine on a laboratory scale whether, in the co-processing of fossil and renewable feeds, the feeds should be blended before the FCC pretreatment unit or if it is more advantageous to blend the renewable feed with a hydrotreated fossil feed. In our view at hte, the future of reaction technology will involve more testing cut out specifically for the targets and boundary conditions of each refinery. A Darrell Rainer, Technical Service Advisor, Darrell. Rainer@ketjen.com , Cliff Avery, Global FCC Process Specialist, Cliff.Avery@ketjen.com , and Jon Strohm, Advisor R&D, James.Strohm@ketjen.com , Ketjen The FCC unit is already one of the most versatile units in the refinery, but we see an increasing demand for flexibility in the coming years. There will be increased interest in pet- rochemicals, particularly from renewable and circular feed- stocks. These changes in product demand and feedstock variability also demand improvements in catalyst design and FCC injectors, regenerator (low to high delta coke), the main column, and the high-pressure system. Regarding feeds, refiners are looking into co-processing recyclable and renewable oils. These feedstocks can range

Catalyst systems are designed to provide the following functionality: • Guard bed • Hydrotreating • Dewaxing or isomerisation. The guard bed reactor catalyst or trap catalyst function- ality is to remove the contaminants not removed in the pretreatment system, or PTU. The trap catalyst is distin- guished by high surface area and low catalyst activity. The objective is to operate the trap bed or guard bed system for the maximum length of time before breakthrough occurs. Developments in trap bed catalysts have extended the life of the system, improving on-stream time. Once the contaminants are removed, catalyst function- ality for hydrogen addition is in the next catalyst bed(s). These catalysts have the following reaction paths: • Decarboxylation • Decarbonisation • Hydrodeoxygenation. The conservation of renewable hydrocarbons in the Catalyst development has led to hydrodeoxygenation reactions producing water instead of CO or CO₂. These improvements increase the selectivity of converting renewable feeds to final products product is the desired goal of the catalyst. The first two reactions, decarboxylation and decarbonisation, produce CO and CO₂, which do not capture the carbons into the final fuel. Catalyst development has led to hydrodeoxygenation reactions producing water instead of CO or CO₂. These catalyst improvements increase the selectivity of convert- ing renewable feeds to final products. The alkanes produced have high cetane but poor cold flow properties. Improving the cold flow properties requires isomerisation or dewaxing of the alkanes. The dewaxing

reactions occur in two types: • Cracking and isomerisation • Isomerisation.

The cracking and isomerisation catalyst are useful to pro- duce SAF, while the isomerisation catalyst is more selective to renewable diesel. Catalyst improvements continue in the dewaxing area to increase selectivity and cold flow prop - erty improvement.

PTQ Q4 2023