Feeding spent coffee grounds into reactors: TFM simulation of a non-mechanical spouted bed type feeder

Autor(es)

Sousa, Lucas Massaro ^{[1, 2]} ; Ferreira, Maria C. ^[2] ; Hou, Qinfu F. ^[1] ; Yu, Aibing B. ^{[1, 3]}

Afiliação do(s) autor(es)

^[1] Monash Univ, Chem Engn Dept, ARC Res Hub Computat Particle Technol, Clayton, Vic 3800 - Australia

^[2] Univ Fed Sao Carlos, Drying Ctr Pastes Suspens & Seeds, Chem Engn Dept, POB 676, BR-13565905 Sao Carlos - Brazil

^[3] Southeast Univ Monash Univ Joint Res Inst, Ctr Simulat & Modelling Particulate Syst, Suzhou 215123 - Peoples R China

• Tipo de documento: Artigo Científico
• Fonte: WASTE MANAGEMENT; v. 109, p. 161-170, MAY 15 2020.
• Citações Web of Science: 0

Resumo

Due to the increasing coffee production, Spent Coffee Grounds' (SCGs) generation has grown dramatically, hence appropriate management of this solid biomass waste is imperative. SCGs can be used as feedstocks for renewable energy and fuel generation provided that a stable feeding of powders to reactors is maintained. Recently, a non-mechanical spouted bed feeder proved itself an excellent alternative in feeding SCGs to a pilot-scale circulating fluidized bed reactor. Nonetheless, further studies are necessary for the feeder's implementation in commercial applications. Here the feeding of SCGs with the spouted bed feeder is addressed by using Computational Fluid Dynamics. Firstly, a Two-Fluid Model (TFM) is validated against experimental data, and then the effects of five operating and design parameters were analyzed aiming at improving the handling of SCGs. The solids flowrate (W-S) in the reactor could be stably controlled from 4 to 30 g/s depending on the settings. The feeder performance is enhanced by operating it under high gas flowrate (Q), high entrainment length (z), and high mass of solids in the feeder (H-S). Using feeders with low cone angle (gamma) or reactors with large diameter (D-R) increases W-S, which is appealing for the operation of medium-to large-scale units. The proposed TFM is a cost-effective tool for implementing spouted bed feeders in commercial applications. With the feeder coupled to the process, SCGs are treated continuously in the reactor for energy generation, thus reducing the disposal problems associated with this waste and improving the management of SCGs globally. (C) 2020 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 18/11031-8 - Estudo sobre o desempenho de válvulas não-mecânicas como alimentadores de pós de biomassa em reatores de leito pneumático circulante: análise via fluidodinâmica computacional (CFD)
• Beneficiário: Lucas Massaro Sousa
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Doutorado Direto
• Processo FAPESP: 16/25946-2 - Estudo sobre o desempenho de válvulas não-mecânicas como alimentadores de pós de biomassa em reatores de leito pneumático circulante
• Beneficiário: Lucas Massaro Sousa
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto