Energy Analysis of an Integrated Plant: Fluidized Bed Steam Gasification of Hydrothermally Treated Biomass Coupled to Solid Oxide Fuel Cells

Alessandro Antonio Papa,Luca Taglieri,Luca Del Zotto,Alberto Gallifuoco,Enrico Bocci,Andrea Di Carlo

doi:10.3390/en14217331

Alessandro Antonio Papa, Luca Taglieri + Show 4 more

Open Access

https://doi.org/10.3390/en14217331

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Abstract

An innovative process based on hydrothermal carbonization, gasification, and solid oxide fuel cells (SOFCs) technologies was developed using a commercial process simulation software called ASPEN Plus. The object of this work is to study plant efficiency under various operating conditions. The hydrothermal pre-treatment (HTC) at 200 and 250 °C was modelled as a black box based on the experimental results. The gasifier was modelled as a single reactor vessel with both the fluidized bed steam gasification of solid fuel and the hot gas cleaning system. The SOFC was modelled as a simple grey box with the ASPEN Plus blocks. The effect of HTC temperature and steam/carbon (S/C) ratio on the syngas composition and yield and plant efficiency was studied. The results show that the gasification of hydrochar obtained at 200 °C with S/C ratio of 0.6 gives the best results, namely an energy output of SOFC equal to 1.81 kW/kgBiomass, and overall process efficiency of 36%.

Highlights

The challenges related to global warming, national energy security, and dependency has brought the need for alternatives to fossil fuels
High S/C ratios increases the production of H2 and CO2 and decrease CO and CH4 concentrations. These results indicate that a higher S/C ratio enhances water gas, steam methane, and water gas shift reaction (WGS) reactions
Hydrothermal carbonization, gasification, and SOFC technologies were studied in a combined process to exploit biomass simulated with ASPEN Plus

Summary

Introduction

The challenges related to global warming, national energy security, and dependency has brought the need for alternatives to fossil fuels. In the last few years, many studies have been carried out to determine the optimal operating conditions, the performance, and the potentials and limitations of various integrated power plant coupling gasifier and SOFC [4,5,6,7,8,9,10,11,12,13,14,15,16]. The results of this study show that the highest electrical exergy efficiency of 49.9% is obtained with air gasification and high temperature gas cleaning at large-scale system. Efficacious tar and sulfur concentration must be low yet in the raw gas from the gasifier This requirement nullifies the great potential of the gasification technology since most of the organic waste is not exploitable unless pre-treatments are carried out on the solid fuel feedstock. Aspen Plus always assigns substreams of type NC to nonconventional solids (i.e., nonconventional solids are coal and wood pulp) [38]

Gasification Model

SOFC Model

2.34. SPOroFcCessMDoedseilgn

Results and Discussion

Conclusions