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Biomass-to-syngas production in catalyst-loaded molten salt: catalytic enhancement and conceptual process design |
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| รหัสดีโอไอ | |
| Title | Biomass-to-syngas production in catalyst-loaded molten salt: catalytic enhancement and conceptual process design |
| Creator | 1. Sakhon Ratchahat 2. Khalid Al-Ali 3. Satoshi Kodama 4. Tawatchai Charinpanitkul 5. Hidetoshi Sekiguchi 6. Wiwut Tanthapanichakoon |
| Publisher | Joint Graduate School of Energy and Environment |
| Publication Year | 2557 |
| Keyword | Syngas, Pyrolysis, CO2 gasification, Ni/Al2O3, Conceptual process design |
| Abstract | Pyrolysis and CO2 gasification were experimentally investigated by direct dispersion of cellulose powder in hightemperature molten salt system (MS). Ni/Al2O3 catalyst was loaded in molten salt (CLMS) to improve the production rate and yield of syngas in both cellulose pyrolysis and CO2 gasification of the pyrolyzed char. A combined CO2 pyrolysis-gasification (CPG) process is known to provide CO-rich syngas while H2 fraction decreased due to the reverse water gas shift reaction (RWGS). In this study, a two-step separate pyrolysis-CO2 gasification (SPG) process in catalystloaded molten salt (CLMS) was proposed to avoid this problem. Four conceptual process designs, namely, SPG in MS, SPG in CLMS, CPG in MS, and CPG in CLMS were carried out and their results compared. Based on a design basis of 100 kmol/h (16,200 kg/h) of cellulose feed, the CPG in MS and CLMS produced 593 kmol/h and 485 kmol/h of syngas with an overall H2:CO ratio of 0.21 and 0.14, respectively, whereas the corresponding values of the SPG in MS and CLMS were 770 kmol/h and 0.58, and 1,137 kmol/h and 0.76, respectively. In addition, the SPG in MS reduced the residual char to 33 from 268 kmol/h for its CPG counterpart. Similarly, SPG in CLMS reduced the residual char to 30 from 239 kmol/h for its CPG counterpart. The required total reactor volumes of SPG (135.4 m3 in MS and161.1 m3 in CLMS) were about half of CPG (272.5 m3 in MS and 310.6 m3 in CLMS). The total heat required for SPG (23,308 kW in MS and 24,832 kW in CLMS) was significantly less than that of CPG (28,404 kW in MS and 26,814 kW in CLMS). The Ni/Al2O3 could enhance the syngas yield, reduced CH4 yield, and increase char conversion. The SPG process in CLMS could exhibit the most effective arrangement of gasifier in terms of both quantity and quality of syngas products, char residual, as well as effective utilization of solar energy. |
| ISBN | 978-616-92228-1-1 |
