Enhancement of hydrogen production in a modified moving bed downdraft gasifier – A thermodynamic study by including tar. (20th April 2017)

• Record Type: Journal Article
• Authors: Adnan, Muflih A.; Susanto, Herri; Binous, Housam; Muraza, Oki; Hossain, Mohammad M.
• Is Part Of: International journal of hydrogen energy. Volume 42:Number 16(2017)
• Page Start: 10971
• Page End: 10985
• Publication Date: 2017-04-20
• Subjects: Biomass gasification -- Hydrogen production -- Tar formation -- Thermodynamic analysis -- Aspen Plus®; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2017.01.156
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: A new approach on thermodynamic simulation of the gasification process is conducted by considering the formation of tar using Aspen Plus. The present model shows higher accuracy as compared to the conventional model in term of the composition of producer gas. The tar from pyrolysis process is successfully reduced with high reaction temperature in the combustion zone. A parametric study is performed by varying the split ratio of gasifying agents (steam/oxygen) through three different zones: (i) combustion zone, (ii) counter-current reduction zone, and/or (iii) co-current reduction zone. Introduction of the gasifying agents through the counter-current reduction zone has positive effects on the gasification performances in term of hydrogen concentration, cold gas efficiency, and gasification system efficiency. The effects of O2 equivalence ratio and steam to carbon ratio (S/C) on the performance of gasification are also investigated. The gasification with oxygen provided the highest cold gas efficiency. A remarkable hydrogen production is achieved from gasification with both oxygen and steam. Highlights: A new model of the biomass gasification is developed using Aspen Plus. The formation of tar is taken into account in the model formulation. The tar from the pyrolysis zone is successfully eliminated in the combustion zone. A remarkable H2 production is achieved using O2 and steam as the gasifying agents. A positive effect is observed as steam is injected to the counter-current reduction zone.