(720a) Mathematical and Experimental Modelling of Biomass Gasification for Hydrogen Production

Lignocellulosic biomass (LB) is nowadays an important raw material that can be used to obtain high value-added products. These residues have a great potential that has not been yet tapped. According to [3], it was estimated that Colombia has a theoretical biomass energy potential ranging between 5 – 18 mio TOE (millions of Tonnes of oil Equivalent). Currently, some industries are using this biomass for the production of electricity from cogeneration systems; however the main use of these residues in Colombia is as traditional fuel for cooking and heating water [4].

Wide range of technologies exists for transforming this energy rich biomass into hydrogen. Thermochemical technologies such as pyrolysis, combustion and gasification are the most interesting concepts, focusing on the use of biomass as source for energy at positive net balances [5]. However, biomass gasification seems to be the most efficiency process for the transformation of these residues into bioenergy. The syngas can be enriched in hydrogen through different methods as catalyst, adsorption, etc [1], [2].

Hydrogen is nowadays a promising source of energy that can be used directly and indirectly as storage fuel with less environmental issues, especially without CO₂ emissions. However, only 4% of hydrogen is produced from renewable sources since high percentage of residual biomass is used directly as feedstock for combustion processes where its energy density is very less.

This paper evaluates the possibility of producing hydrogen from syngas obtained through gasification of agroindustrial residues from Colombia: Coffee Cut-Stems and Pinus Patula, using air as gasifying agent. Raw Materials were characterized by measuring extractives content (NREL/TP-510-42619), ash content (NREL/TP-510-42622), holocellulose content (ASTM Standard D1104), cellulose content (TAPPI 203 os-74 method) and acid-insoluble lignin (TAPPI T222). The separation of hydrogen from syngas was simulated using the software Matlab. The energy analysis was carried out using the commercial package Aspen Plus v8.0 (from Aspen Technology, Inc., USA). Besides, eight environmental categories were evaluated using the waste reduction algorithm developed by the Environmental Protection Agency (EPA).  In order to feedback the simulation step, verification experiments were developed at small scale using “GEK Gasifier (10 KW/h) Power Pallet” located at the Instituto de Biotecnología y Agroindustria at Universidad Nacional de Colombia, Manizales. The gas produced was analyzed (CO, H2, CO2, CH4) using a portable syngas infrared analyzer (GASBOARD-3100P).

The results demonstrated that the concentration of hydrogen in the syngas after gasification is the key factor to define the future of this technology as source of hydrogen. Additionally, the scale of plant (including gasification and separation with membranes) together with the type of gasifying agent can change dramatically these results.

References
[1] S. G. Gopaul, A. Dutta, and R. Clemmer, “Chemical looping gasification for hydrogen production: A comparison of two unique processes simulated using ASPEN Plus,” Int. J. Hydrogen Energy, vol. 39, no. 11, pp. 5804–5817, 2014.
[2] A. a. Olajire, “CO2 capture and separation technologies for end-of-pipe applications - A review,” Energy, vol. 35, no. 6, pp. 2610–2628, 2010.
[3] Salazar. M, Venturini. M, Poganietz. W, Finkenrath. M, Kirsten. T, Acevedo. H, Bioenergy technology roadmap for Colombia, Universitá degli Studi di Ferrara, 2014.
[4] Luis E. Rincón, Luis A. Becerra, Jonathan Moncada, Carlos A. Cardona, Techno-economic analysis of the use of Fired Cogeneration Systems based on sugar cane bagasse in South Eastern and Mid-Western regions of Mexico, Waste and Biomass Valorization, Vol 5, pp. 189-198, 2014.
[5] Parthasarathy. P, Narayanan. K, Hydrogen production from steam gasification of biomass. Influence of process parameters on hydrogen yield – A review, Renewable Energy, pp. 570-579, 2014.