Plasma fixed bed gasification using an Eulerian model

• Published in: International journal of hydrogen energy Vol. 44; no. 54; pp. 28668 - 28684
• Main Authors: Ismail, Tamer M., Ramos, Ana, Abd El-Salam, M., Monteiro, Eliseu, Rouboa, Abel
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 05-11-2019
• Subjects: Euler-Euler approach; Fixed bed; Municipal solid wastes; Plasma gasification; Euler-Euler approach; Municipal solid wastes; Plasma gasification; Fixed bed
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2019.08.035

Gasification of solid waste is considered as a green and sustainable solution to perform energy recovery from several waste streams. This work aims to adapt an Euler-Euler multiphase mathematical model to understand the effects of physical and chemical factors, i.e. equivalence ratio (ER), steam to fuel ratio (SFR), and input plasma power of municipal solid waste (MSW) fixed bed gasification. The model is capable of simulating temperature and velocity fields, as well as gas and solid composition variations inside the reactor. A two-step pyrolysis model is used considering the pyrolysis mechanism of cellulose and plastic components. Drying, pyrolysis, homogeneous gas reactions, and heterogeneous combustion/gasification reactions were also included in the model. It was shown that the proposed model could provide accurate predictions against experimental data with a deviation generally lesser than 10%. Conclusion could be drawn that an ER of 0.3 and an SRF of 0.5 seems to be the most favourable conditions in order to obtain a high-quality syngas. Higher plasma power is favourable to obtain a high-quality syngas. However, the high electric power required penalizes the process efficiency and may compromise the economic viability of a plasma gasification project.
•A numerical model was developed to simulate plasma gasification of solid residues.•The effect of operational conditions on syngas was assessed for optimized results.•Accurate predictions were seen, comparing numerical results with experimental data.•A balance between plasma power, syngas quality and process efficiency must be set.•Syngas with lower heating value of 7.5 MJ/Nm3 was achieved.