Massaro Sousa, Lucas ORCID: https://orcid.org/0000-0002-4182-9347, do Carmo Ferreira, Maria, Hou, Qinfu and Yu, Aibing (2020) Feeding spent coffee grounds into reactors: TFM simulation of a non-mechanical spouted bed type feeder. Waste Management, 109. pp. 161-170. ISSN 0956-053X (doi:10.1016/j.wasman.2020.04.056)

PDF (AAM) 35831_SOUSA_Feeding_spent_coffee_grounds.pdf - Accepted Version Restricted to Repository staff only Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (977kB) | Request a copy

Abstract

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 (WS) 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 (HS). Using feeders with low cone angle (γ) or reactors with large diameter (DR) increases WS, 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.

Item Type:	Article
Uncontrolled Keywords:	feeding device; spent coffee grounds; two-fluid model; spouted bed; CFD
Subjects:	S Agriculture > S Agriculture (General) T Technology > TJ Mechanical engineering and machinery
Faculty / School / Research Centre / Research Group:	Faculty of Engineering & Science Faculty of Engineering & Science > School of Engineering (ENG) Faculty of Engineering & Science > Wolfson Centre for Bulk Solids Handling Technology
Last Modified:	24 Jun 2022 14:16
URI:	http://gala.gre.ac.uk/id/eprint/35831

Actions (login required)

View Item

Downloads