Cold flow analysis for a scaled bubbling fluidized bed gasifier: - PowerPoint PPT Presentation

NETL 2018 Workshop On Mult ltip iphase Flo low Scie ience Cold flow analysis for a scaled bubbling fluidized bed gasifier: impact of various feedstocks and fluidizing materials Ali li Si Sivr vri 1 Amoo moolya La Lals lsar are 2 Cosmin osmin Dumitr umitrescu escu 1 Joh ohn n Hu Hu 2 1 Center for Alternative Fuels Engines and Emissions (CAFEE) Department of Mechanical & Aerospace Engineering, West Virginia University 2 Department of Chemical Engineering, West Virginia University 1 Benjamin M. Statler College of Engineering and Mineral Resources

Objectives • Cold flow analysis allows us to simulate the process and obtain the hydrodynamic properties of the reaction bed. • Good-mixture and good-fluidization conditions have been observed (air volumetric flow rate, static bed height, fluidizing material type and feedstock) • Premixed and not premixed cases have been compared. Benjamin M. Statler College of Engineering 2 and Mineral Resources

Experimental Setup Benjamin M. Statler College of Engineering 3 and Mineral Resources

Material Characteristics Table 1. Material size and sphericity analysis Material Average of Average of particle Sphericity size (µ m) Hardwood 432 0.564 Coal 310 0.761 Glass beads 279 0.933 Sand 368 0.863 Benjamin M. Statler College of Engineering 4 and Mineral Resources

Table 2. Material bulk density and voidage analysis Material Bulk Voidage (Mixtures) density (%) (g/cc) Glass beads + coal 1.61 35 Glass beads + hardwood 1.43 38 Sand + coal 1.56 41 Sand + hardwood 1.38 44 Benjamin M. Statler College of Engineering 5 and Mineral Resources

Pressure drop versus air volumetric flow rate diagrams • Static bed height effect 1.1 Glass beads and hardwood 1.0 300~350 m 7 3/4” 0.8 P Normalized 100 gr 0.6 200 gr 300 gr 5” 0.4 0.2 2 1/2” 0 2 4 6 8 10 12 Q air (SLM) Benjamin M. Statler College of Engineering 6 and Mineral Resources

• In the premixed case better fluidization obtained 12 1.2 Glass beads and hardwood, MIXED Glass beads and hardwood, MIXED 300~350 m 300~350 m 10 1.0 100 gr 200 gr 8 0.8 300 gr P 100 gr P (in H 2 O) Norm 200 gr Normalized 300 gr 6 0.6 0.4 4 0.2 2 0 2 4 6 8 10 12 0 2 4 6 8 10 12 Q air (SLM) Q air (SLM) Benjamin M. Statler College of Engineering 7 and Mineral Resources

• Bulk density and voidage effect 1.2 12 Sand and hardwood Sand and hardwood 300~350 m 300~350 m 1.0 10 97 gr 97 gr 194 gr 194 gr 291 gr 291 gr 0.8 8 P P (in H 2 O) Normalized 0.6 6 0.4 4 0.2 2 0 2 4 6 8 10 12 0 2 4 6 8 10 12 Q air (SLM) Q air (SLM) Benjamin M. Statler College of Engineering 8 and Mineral Resources

16 1.6 97 gr 14 97 gr 1.4 194 gr 194 gr 291 gr 12 1.2 291 gr P 10 1.0 P (in H 2 O) Normalized Sand and hardwood, MIX 8 0.8 300~350 m 6 0.6 4 0.4 Sand and hardwood, MIX 300~350 m 2 0.2 0 2 4 6 8 10 12 0 2 4 6 8 10 12 Q air (SLM) Q air (SLM) Benjamin M. Statler College of Engineering 9 and Mineral Resources

• Coal and glass beads mixture has the highest bulk density and the lowest voidage ratio 10 1.0 Glass beads and coal Glass beads and coal 300~350 m 300~350 m 7 1/8” 8 0.8 P (in H 2 O) P 6 0.6 98 gr Normalized 98 gr 196 gr 196 gr 294 gr 4 5/8” 4 0.4 294 gr 0.2 2 2 1/4” 0 2 4 6 8 9 0 2 4 6 8 9 Q air (SLM) Q air (SLM) Benjamin M. Statler College of Engineering 10 and Mineral Resources

10 1.0 8 0.8 98 gr 196 gr 294 gr 98 gr P (in H 2 O) P 196 gr 6 0.6 Normalized 294 gr Glass beads and coal, MIX 4 0.4 Glass beads and coal, MIX 300~350 m 300~350 m 2 0.2 0 2 4 6 8 9 0 2 4 6 8 10 Q air (SLM) Q air (SLM) Benjamin M. Statler College of Engineering 11 and Mineral Resources

12 1.2 Sand and coal Sand and coal 300~350 m 300~350 m 10 1.0 95 gr 190 gr 8 P 0.8 285 gr P (in H 2 O) 95 gr Normalized 190 gr 6 0.6 285 gr 4 0.4 2 0.2 0 2 4 6 8 10 12 0 2 4 6 8 10 12 Q air (SLM) Q air (SLM) Benjamin M. Statler College of Engineering 12 and Mineral Resources

12 1.2 Sand and coal, MIX Sand and coal, MIX 300~350 m 300~350 m 10 1.0 95 gr 95 gr 190 gr 190 gr 285 gr 8 0.8 P 285 gr P (in H 2 O) Normalized 6 0.6 4 0.4 2 0.2 0 2 4 6 8 10 12 0 2 4 6 8 10 12 13 Q air (SLM) Q air (SLM) Benjamin M. Statler College of Engineering 13 and Mineral Resources

High speed imaging Benjamin M. Statler College of Engineering 14 and Mineral Resources

Mixture analysis 30 fps Movie 1. Glass beads and coal • Mostly homogenous bubbling Benjamin M. Statler College of Engineering 15 and Mineral Resources

Movie 2. Sand and coal Benjamin M. Statler College of Engineering 16 and Mineral Resources

Movie 3. Sand and hardwood with FCC catalyst FCC Catalyst Benjamin M. Statler College of Engineering 17 and Mineral Resources

Movie 4. Glass beads and hardwood with FCC catalyst FCC Catalyst and wood mixture Benjamin M. Statler College of Engineering 18 and Mineral Resources

Summary and Conclusions • Better fluidization obtained for glass beads and coal because of its higher bulk density and lower voidage ratio. • Good-mixture case for hardwood and fluidizing material mixture obtained between 2-2.5 times of minimum fluidization velocity. • FCC catalyst acted like a bottom ash for sand and hardwood mixture. • In addition to this study, studies of parametric reaction kinetics of biomass, coal, catalytic and non-catalytic gasification based on thermogravimetric analysis (TGA) and fixed bed reactor have been done by our group to develop optimized reaction operating conditions for fluidized bed gasifier. Benjamin M. Statler College of Engineering 19 and Mineral Resources

Acknowledgements Department of Energy and National Special thanks to Energy Technology Laboratory , Morgantown Centre for their technical and financial support. Benjamin M. Statler College of Engineering 20 and Mineral Resources

Thank You Questions Benjamin M. Statler College of Engineering 21 and Mineral Resources