Innovative processes for thermochemical SNG production from biomass

Transcription

1 Innovative processes for thermochemical SNG production from biomass DVGW - EDGaR First Joint Conference Dominic Buchholz DVGW Forschungsstelle - Gastechnologie am Engler-Bunte-Institut des Karlsruher Instituts für Technologie (KIT) Arnhem

2 Outline 1. Motivation Gasification, a challenge 2. Hot Gas Cleaning Concept 3. Results Tar Reforming Methanation in Honeycomb Reactors 4. Modeling of Honeycomb Reactors 5. Power-to-Gas Integration 6. Conclusions 2

3 Motivation Biomass Gasification Syntheses SNG Fischer-Tropsch MeOH DME Synthesis gas and Contaminants CO H 2 H 2 O CO 2 + Particles Tars Na + K NH 3 + HCN H 2 S + COS + CS 2 Halogens 3

4 Gasification Allothermal Dual Fluidized Bed Steam Gasification Type FICFB Güssing with/without AER DFB AER Comp. y i,tr in vol.-% H CO CO CH x i in vol.-% H 2 O Diagram: Specht, ZSW Contaminants H 2 S up to 250 ppm-v,dry COS up to 200 ppm-v,dry Phenol ~ 4000 mg/m 3,dry 4

5 Hot Gas Cleaning Concept S-tolerant dusty tar reformer filter H 2 S adsorber CO shift methanation drying CO 2 scrubber SNG raw gas dust alkalimetals water CO C C C 40 C Advantages: less heat exchangers increased efficiency by utilization of the heating value of the tar conversion of all S-species into H 2 S LT-H 2 S adsorption is state of the art LT-filtration is state of the art Drawbacks: S-tolerant dusty tar reforming is still under R&D lack of long-term operating experience (loss of efficiency by partial oxidation of syngas) 5

6 Sulfur Tolerant Tar Reforming = 1,01 bar GHSV = 4000 /h X phenol,in = 5000 mg/m³,dry = 200 ppm-v,dry y COS,in 6

7 SNG Production - Main Reactions Reactions and Thermodynamic Limitations Reaction Equotations: CO-Methanation CO 2 -Methanation Water-Gas-Shift Boudouard-Reaction Characteristics of Methanation Reaction: High Heat of Reaction: Methane Formation is preferred at low Temperatures Molar Contraction: Increase of Pressure raises Methane Yield Efficient removal of reaction heat is main issue 7

8 SNG Production Metallic Honeycomb Reactors General layout: system of parallel channels coated with catalyst in a metallic monolith First Fields of Application of Honeycomb Reactors: automobile exhaust gas cleaning flue gas cleaning Further Fields of Application: highly endo- oder exothermic reactions fuel gas purification for fuel cell applications reforming 200 cpsi 1) 400 cpsi 1) Channels per square inch 8

9 Temperature Profile section A-A A R 2 = 16,5 mm R 1 = 11 mm D = 35 mm L hc = 50 mm T = 240 C, τ mod = 100 kg. s/mol, X CO = 0,36 T = 260 C, τ mod = 100 kg. s/mol, X CO = 1,0 A Temperature [ C] T R in C Temperature [ C] T R in C aktive bedwabenlänge length L in [cm] cm aktive bedwabenlänge length L [cm] in cm 9

10 CFD Modeling Geometry Generation pixel-graphic 3D-design vector-graphic meshing Ansys Workbench CAD-design simulation Grimbichler, J., Engler-Bunte-Institut, (2011) 10

11 CFD Modeling Calculated Temperature Distribution flow direction Temperature T in K Kunz, S., Engler-Bunte-Institut, (2012) 11

12 Future Demand for Power-to-Gas Peak Capacity Estimates for Germany Needed storage power: 25 GW Needed storage capacity: TWh KIC InnoEnergy The leading engine for Innovation and Entrepreneurship in Sustainable Energy Speaker: Dominic Buchholz 12

13 KIC Project Demo-SNG Structure DVGW EBI KIT KTH CORTUS Cortus Woodroll Gasifier KTH DVGW Hot Gas Cleaning SNG production DVGW KIT SNG a b c solar power generation Wind power generation Study water electrolysis KIC InnoEnergy The leading engine for Innovation and Entrepreneurship in Sustainable Energy Speaker: Dominic Buchholz 13

14 Process simulation PtG Theoretical Methane Yields / Temperature Limitations Merkle, S., Engler-Bunte-Institut, (2012) 14

15 Conclusions methane yield can be increased with Hot Gas Cleaning concept by converting tar into additional synthesis gas by hydrogen addition, stemming from water electrolysis (Power-to-Gas), the methane yield can be increased significantly sulfur tolerant tar reforming simplifies the process chain metallic honeycomb reactors allow advanced temperature control Modeling of honeycomb reactors simplifies process optimization and the up scaling 15

16 Thank You for your kind attention Dipl.-Ing. Dominic Buchholz Tel.: 0721 / ; buchholz@dvgw-ebi.de 16