1. Catalytic conversion of pyrolysis gas in the WoodRoll process for enhanced process reliability
Pouya H. Moud1), Dennis Fällén Holm1), Alfred Halvarsson1), Klas Andersson2), Efthymios Kantarelis1), Marko Amovic3), Rolf Ljunggren3), Klas Engvall1)
1) KTH, Dept of Chemical Engineering, Stockholm
2) Haldor Topsoe A/S, Kgs. Lyngby, Denmark
3) Cortus Energy AB, Kista
Nyheter och forskningsresultat om energigas 8-9 June 2017, Göteborg

2. Scope of study
The scope of the project was to perform an early evaluation of a technical solution, based on a catalytic conversion, simplifying the conveying of the pyrolysis gas in pipelines and valves, as well as improve combustion properties in the radiant heat tube burners.
”Raw pyrolysis gas with 35-40% oil”
Filter
Catalytic reactor
Burners
”Energy gas with lighter CxHy”
Pyrolytic residues

3. Outline Cortus Energy The WoodRoll® technology
Experimental tests and methods
Results enhanced process reliability
Other potential applications
Summary

4. 1. Cortus Energy

5. Cortus Energy
Founded in 2006 to develop and commercialize the patented gasification process WoodRoll®.
WoodRoll® is a gasification process for biomass, producing clean energy gas with a high energy value.
The purity and high energy value of the energy gas makes it suitable for replacing fossil fuels.
Listed on Nasdaq OMX First North since february 2013.
The company has 12 employees and 10 consultants.

6. 2. The WoodRoll® technology

7. The WoodRoll® technology
Tar free product gas
The WoodRoll® thermal gasification technology is an integrated process for converting wet solid biomass to clean syngas in three steps, drying, pyrolysis and gasification. The process is fully allothermal from wet biomass to clean syngas. Tar and higher hydrocarbons in a pyrolysis gas is incinerated to indirectly generate the heat for the endothermic gasification process. Excess heat is used counter current the biomass processing to syngas. This means that the hot flue gases from the indirect heating of the gasifier is the heat source for the pyrolysis process. Finally, the excess heat from the pyrolysis is enhancing the dryer. In this manner a thermal yield of 80% can be reached for wet biomass to clean syngas.

8. The WoodRoll® technology
Biofuels
20 biofuels verified
Drying
Controlled dusting and condensate
Single percentage humidity in operation
Pyrolysis
Combustion stable
Char yield [T, Xi] 35% ±10%
Pyrolysis oil yield 35% ±10%
Gasification
>99% Conversion rate reached
Ash melting only for chemical sludge
Clean product gas

9. 3. Experimental setup and methods

10. Experimental setup and methods
Experiments on-site in Köping
Wood chips of GROT
Real biomass pyrolysis gas including bio-crude
Sampling before and after catalytic reactor
Tests included Fe-based material and dolomite mineral as catalysts

11. Experimental setup and methods
Pyrolysis gas line
Pyrolyser
Burner
Permanent gases and oil samples

12. Experimental setup and methods
Pyrolysis oil sampling
Basic evaluation
Permanent gas analysis
Bio-crude analyses
Gravimetric
C/H/O
Catalyst characterization
Surface area
Carbon laydown
TPO
XRD
Mass balance evaluation for C,H,O
Extended analysis
Bio-crude analyses
H-NMR
GC/MS
Proposed mechanism

13. 4. Results enhanced process reliability

14. Experimental conditions
Experimental conditions using Fe-based catalyst
The pyrolysis gas was treated under stable conditons for 8 hours with the iron-based catalyst
The dolomite bed collapsed totally after 30 minutes of use

15. Operational stability catalytic bed
T-profile inside the reactor versus time on stream
Initial activation
Stable operation TC TC TC
Successful activation of the catalyst
Fluctuation in temperature due to initial activation
Stable T-profiles after activation
Catalytic effect remained despite surface S and C

16. Permanent gases Average molar flow rates of permanent gases
A significant increase of hydrogen
Increase in H2 and CO2 content WGS activity

17. Mass distribution and bio-crude analysis
C/H/O analysis (dry basis), water content, S/C, O/C, and H/C of the raw and treated solvent-free condensate
51% reduction in bio-crude content
Decrease in oxygen content
Increase in S/C ratio => lower carbon formation on catalyst

18. Burner performance
More rapid combustion of the treated pyrolysis gas, resulting in a more evenly distributed temperature profile.
Combustion zone for treated oil is longer than raw oil.

19. Burner performance
Lower NOx implies a more uniform combustion

20. 5. Other potential applications

21. A step for pre-conditioning
The change of pyrolysis oil to lighter hydrocarbons, the lowering of oxygen content and the change in permanent gases implies a possible use of the as a pre-conditioning step.
Evaluation point at dehydration/decarbonylation of hydrocarbons followed by a subsequent water-gas shift reaction
Paper describing in-depth analysis and mechanism is submitted and under review.
Dehydration: R-CH2-OH R=CH + H2O
Decarbonylation: R-CHO R-H + CO
Water-gas shift: CO + H2O CO2 + H2
Potential catalytic process

22. 6. Summary

23. Summary
The catalytic process was successfully used for 8 hours in real pyrolysis gas converting heavy hydrocarbons to lighter ones.
A reduction in the amount of bio-crude of approximately 51 % could be achieved in the tests.
The gas volume increased significantly after the conversion.
The composition of the pyrolysis oil also changed. For example, the amount of oxygen was dramatically reduced after the conversion. Implying less oxygenated compounds.
The combustion of the gas in the radiant tube burner displayed a changed behaviour using the treated pyrolysis gas. The combustion started closer to the burner nozzle, which means a longer flame.
The iron-based catalytic process has the potential as a pre-reformer step (pre- reformer concept) for bio-crude rich pyrolysis gas
The production of hydrogen from pyrolysis gas without hydrogen/steam addition in atmospheric pressure seems to be a viable pathway for hydrogen- rich gas production
Experiments with longer exposure time is necessary to investigate the lifetime of the catalyst

24. KTH collaborators and funding partners

25. Questions?