Techno-Economic Evaluation of Deoxygenation Methods of Pyrolysis Oil
(2025) KETM05 20251Chemical Engineering (M.Sc.Eng.)
- Abstract
- This master’s thesis investigates deoxygenation strategies for biomass-derived pyrolysis oil (PO). The study focuses on industrial scalability, economic feasibility, and compatibility with existing refinery infrastructure. It was conducted in collaboration with Preem AB, aligning with their renewable fuel initiatives. The high oxygen content and instability of PO present challenges when integrated into conventional refining units, such as catalyst deactivation and corrosion. Therefore, this work evaluates approaches that can stabilize and improve the properties of PO in order to be introduced to conventional refinery processes, while remaining economically and environmentally viable.
The first part of the thesis consists of a literature... (More) - This master’s thesis investigates deoxygenation strategies for biomass-derived pyrolysis oil (PO). The study focuses on industrial scalability, economic feasibility, and compatibility with existing refinery infrastructure. It was conducted in collaboration with Preem AB, aligning with their renewable fuel initiatives. The high oxygen content and instability of PO present challenges when integrated into conventional refining units, such as catalyst deactivation and corrosion. Therefore, this work evaluates approaches that can stabilize and improve the properties of PO in order to be introduced to conventional refinery processes, while remaining economically and environmentally viable.
The first part of the thesis consists of a literature review, analyzing current upgrading technologies. This includes evaluation of current scale, results and up-scaling challenges. Based on this review and technical assessment, a process scheme is proposed that includes an initial stabilization step followed by mild hydrotreating and catalyst recycling. The findings recommend early onsite stabilization at the PO production facility, organic solvent addition proposed, to prevent aging and polymerization reactions. This is followed by a hydrotreating step, using slurry hydrocracking at the refinery. This approach offers robust method for upgrading PO so that it can be co-processed in existing refinery infrastructure, such as fluid catalytic cracker, agreeing with Preem’s ambition to reduce dependence on fossil feedstocks.
A techno-economic analysis of an upscaled version of the process was conducted to identify key cost drivers, investment and operational costs. Further on, a net carbon dioxide emission assessment was performed to evaluate the environmental impact of the process. The analysis was based on two scenarios: one using fossil-derived feedstocks and utilities, and the other using renewably based sources, to enable comparisons on price differences and carbon dioxide reductions. The total capital cost was calculated to 197 million SEK, assumingly underestimated due to simplifications and uncertainties. Nevertheless, the analysis identified the primary cost drivers during operation which is highly valuable for future work. In both scenarios, the cost of PO was the dominating cost, which cannot be avoided. Additionally, methanol and bio-methanol were identified as the second largest cost contributors. The estimated price of PO was 23 SEK/kg PO in the fossil scenario, and 28 SEK/kg PO in the renewable scenario.
The carbon dioxide emissions varied significantly between the two cases, estimated to 4.8 kg CO2/kg PO and 0.2 kg CO2/kg PO in the fossil and green scenario respectively. These results demonstrate that a greener operation does not result in an unacceptable cost increase, but offers a dramatical reduction in emissions.
Further on, the results highlight the importance of early stabilization to prevent oil degradation and equipment corrosion. Further on, this is followed by a hydroprocessing stage resistant to coke formation that can manage feedstock with variations in content. The study concludes that, with optimized process design and conditions, upgraded PO can play a significant role in Sweden’s transition toward a renewable energy future while cost competing with fossil fuel. (Less) - Popular Abstract (Swedish)
- Med den rådande klimatkrisen står vi mitt i en stor omställning. EU:s mål om ett klimatneutralt Europa till 2050 innebär att kraftiga minskningar i utsläpp måste ske. Transportsektorn är särskilt viktig, eftersom den står för ungefär en tredjedel av Sveriges växthusgasutsläpp och är idag nästan uteslutande beroende av fossila bränslen. Detta är inte helt enkelt, transportsektorn är oflexibel och infrastrukturen är byggd efter fossila råvaror.
För att klara denna omställning måste förnybara alternativ ersätta konventionell olja i raffinaderier och i befintliga förbränningsmotorer. Preem har tagit ett viktigt initiativ, och tillsammans med sågverket Setra startat dotterbolaget Pyrocell. Pyrocell producerar en typ av bio-olja av... (More) - Med den rådande klimatkrisen står vi mitt i en stor omställning. EU:s mål om ett klimatneutralt Europa till 2050 innebär att kraftiga minskningar i utsläpp måste ske. Transportsektorn är särskilt viktig, eftersom den står för ungefär en tredjedel av Sveriges växthusgasutsläpp och är idag nästan uteslutande beroende av fossila bränslen. Detta är inte helt enkelt, transportsektorn är oflexibel och infrastrukturen är byggd efter fossila råvaror.
För att klara denna omställning måste förnybara alternativ ersätta konventionell olja i raffinaderier och i befintliga förbränningsmotorer. Preem har tagit ett viktigt initiativ, och tillsammans med sågverket Setra startat dotterbolaget Pyrocell. Pyrocell producerar en typ av bio-olja av sågspånsspill från sågverket som kallas pyrolysolja. Den tillverkas genom att sågspån hettas upp utan syre, då förångas flyktiga komponenter och kondenseras därefter. Sågspån är en ytterst relevant biomassa att utnyttja till något värdefullt eftersom det finns i sådant överskott, samt att den inte konkurrerar med matolja som många biobränslen baseras på. Idag blandas rå pyrolysolja in i Preems katalytiska cracker tillsammans med råolja i en mindre skala. Detta är utmanande för enheten och driftkostnaderna är dyra. Detta på grund av att pyrolysoljan innehåller signifikanta skillnader i egenskap och innehåll mot fossil olja, där framför allt den höga syrehalten skapar vid vidare behandling på raffinaderiet. Dessa utmaningar inkluderar instabilitet, korrosion och deaktivering av katalysator. För att kunna utnyttja oljan måste syret därför tas bort i en process som kallas deoxygenering, men idag finns inga storskaliga anläggningar för denna uppgradering. Det är dessutom oklart vilka metoder som är mest lovande och ekonomiskt försvarbara.
Därför är syftet med examensarbetet att utvärdera olika uppgraderingsmetoder, med främsta fokus att avlägsna syret ur pyrolysoljan. Genom att föreslå en möjlig process och beräkna investerings-och driftkostnader samt koldioxidutsläpp, undersöks om tekniken är ekonomiskt hållbar med en mindre klimatpåverkan än fossil oljeförädling.
Uppgraderingsprocessen bör ske i flera steg, med stabilisering, vätebehandling och samproccessa i raffinaderiet med fossil råvara som föreslagen process. Av dessa är det: tillsatts av metanol, följt av slurry hydrocracking och till sist, 10 vikt% inmatning av pyrolysolja i raffinaderiets katalytiska kracker tillsammans med fossil olja. Dessa metoder är simpla, lovande, ekonomiskt försvarbara och har låg klimatpåverkan. En utökning av pyrolysolja i fossila bränslen kan bidra till att göra transportsektorn mer klimatsmart och samtidigt skapa nya möjligheter för svensk skogsindustri att utveckla värdefulla och hållbara bränslen ur sina restprodukter. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9209157
- author
- Kristensson, Isabel LU and Bärring, Sanna LU
- supervisor
- organization
- alternative title
- Tekno-ekonomisk utvärdering av deoxygenering av pyrolysolja
- course
- KETM05 20251
- year
- 2025
- type
- H2 - Master's Degree (Two Years)
- subject
- keywords
- Renewable fuels, Bio-oil, Biofuels, Lignocellulosic biomass, Techno-economic analysis, Slurry Hydrockracking, Capital cost estimation, Upgrading technologies, Pyrolysis oil, Process Design, Second-generation feedstock, Upgrading, Chemical engineering, Deoxygenation
- language
- English
- id
- 9209157
- date added to LUP
- 2025-08-18 11:43:08
- date last changed
- 2025-08-18 11:43:08
@misc{9209157,
abstract = {{This master’s thesis investigates deoxygenation strategies for biomass-derived pyrolysis oil (PO). The study focuses on industrial scalability, economic feasibility, and compatibility with existing refinery infrastructure. It was conducted in collaboration with Preem AB, aligning with their renewable fuel initiatives. The high oxygen content and instability of PO present challenges when integrated into conventional refining units, such as catalyst deactivation and corrosion. Therefore, this work evaluates approaches that can stabilize and improve the properties of PO in order to be introduced to conventional refinery processes, while remaining economically and environmentally viable.
The first part of the thesis consists of a literature review, analyzing current upgrading technologies. This includes evaluation of current scale, results and up-scaling challenges. Based on this review and technical assessment, a process scheme is proposed that includes an initial stabilization step followed by mild hydrotreating and catalyst recycling. The findings recommend early onsite stabilization at the PO production facility, organic solvent addition proposed, to prevent aging and polymerization reactions. This is followed by a hydrotreating step, using slurry hydrocracking at the refinery. This approach offers robust method for upgrading PO so that it can be co-processed in existing refinery infrastructure, such as fluid catalytic cracker, agreeing with Preem’s ambition to reduce dependence on fossil feedstocks.
A techno-economic analysis of an upscaled version of the process was conducted to identify key cost drivers, investment and operational costs. Further on, a net carbon dioxide emission assessment was performed to evaluate the environmental impact of the process. The analysis was based on two scenarios: one using fossil-derived feedstocks and utilities, and the other using renewably based sources, to enable comparisons on price differences and carbon dioxide reductions. The total capital cost was calculated to 197 million SEK, assumingly underestimated due to simplifications and uncertainties. Nevertheless, the analysis identified the primary cost drivers during operation which is highly valuable for future work. In both scenarios, the cost of PO was the dominating cost, which cannot be avoided. Additionally, methanol and bio-methanol were identified as the second largest cost contributors. The estimated price of PO was 23 SEK/kg PO in the fossil scenario, and 28 SEK/kg PO in the renewable scenario.
The carbon dioxide emissions varied significantly between the two cases, estimated to 4.8 kg CO2/kg PO and 0.2 kg CO2/kg PO in the fossil and green scenario respectively. These results demonstrate that a greener operation does not result in an unacceptable cost increase, but offers a dramatical reduction in emissions.
Further on, the results highlight the importance of early stabilization to prevent oil degradation and equipment corrosion. Further on, this is followed by a hydroprocessing stage resistant to coke formation that can manage feedstock with variations in content. The study concludes that, with optimized process design and conditions, upgraded PO can play a significant role in Sweden’s transition toward a renewable energy future while cost competing with fossil fuel.}},
author = {{Kristensson, Isabel and Bärring, Sanna}},
language = {{eng}},
note = {{Student Paper}},
title = {{Techno-Economic Evaluation of Deoxygenation Methods of Pyrolysis Oil}},
year = {{2025}},
}