KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 10 of 17

Some of the metrics are blocked by your
consent settings
NiO-YSZ anode composite material derived from mechano-chemical for solid oxide fuel cells application
(2025-06-01)
Srisuwan, Thanakorn
;
Puengjinda, Pramote
;
Kaewtrakulchai, Napat
;
Chanpee, Sirayu
;
Jadsadajerm, Supachai
This study investigates the effects of calcination time, milling duration, and sintering temperature on the properties of Nickel oxide and Yttria-stabilized zirconia (NiO-YSZ) anode composite materials for solid oxide fuel cell (SOFC) applications. NiO nanoparticles were synthesized from nickel (II) sulfate (Ni(II)SO<inf>4</inf>), with X-ray diffraction (XRD) confirming a face-centered cubic (FCC) structure. The crystallite size (21 nm) was achieved after 8 hours of calcination, while prolonged durations caused particle agglomeration. Ball-milling for 12 hours produced comparatively fine particles with an average of 706 nm, though extended milling led to grain growth and aggregation. Scanning electron microscopy (SEM) revealed nano aggregation. Sintering at 1200 °C improved the densification of the NiO-YSZ layer while increasing its porosity, which enhanced the reduction of NiO to metallic nickel (Ni). Electrochemical Impedance Spectroscopy (EIS) demonstrated lower impedance and improved electrochemical performance for cells cold-sintered at 1200 °C. These findings show the importance of optimizing processing conditions to enhance the performance of NiO-YSZ anode for SOFCs, offering valuable insights for advanced energy conversion technologies.
Some of the metrics are blocked by your
consent settings
Comparative Study on Performance of SOFC-GT with/without Anode Exhaust Gas Recirculation
(2023-01-01)
Pholboorn, Suthin
;
Saebea, Dang
;
Patcharavorachot, Yaneeporn
The comparative study on the electrical performance of solid oxide fuel cell combined with gas turbine with/without anode exhaust gas recirculation (SOFC-GTR/SOFC-GT-NR) was presented in this work. Performance analysis was performed through Aspen Plus simulator software. The SOFC system was included the pre-reforming process of methane. The simulation results revealed that the SOFC-GT-R has the maximum efficiency of 81.97% at pre-reforming percentage of 10% and fuel utilization of 0.90 while the highest performance of SOFC-GT-NR is 77.60% at pre-reforming percentage of 70% and fuel utilization of 0.90. From the comparative study, it was found that the SOFC-GT-R has higher efficiency by using lower pre-reforming percentage compared with SOFC-GT-NR.
Some of the metrics are blocked by your
consent settings
Energy and exergy analyses of a hybrid system containing solid oxide and molten carbonate fuel cells, a gas turbine, and a compressed air energy storage unit
(2021-10-11)
Jienkulsawad, Prathak
;
Patcharavorachot, Yaneeporn
;
Chen, Yong Song
;
Arpornwichanop, Amornchai
Design of a hybrid system composed of a solid oxide fuel cell (SOFC), molten carbonate fuel cell (MCFC), gas turbine (GT), and an advanced adiabatic compressed air energy storage (AA-CAES) based on only energy analysis could not completely identify optimal operating conditions. In this study, the energy and exergy analyses of the hybrid fuel cell system are performed to determine suitable working conditions for stable system operation with load flexibility. Pressure ratios of the compressors and energy charging ratios are varied to investigate their effects on the performance of the hybrid system. The hybrid fuel cell system is found to produce electricity up to 60% of the variation in demand. A GT pressure ratio of 2 provides agreeable conditions for efficient operation of the hybrid system. An AA-CAES pressure ratio of 15 and charging ratio of 0.9 assist in lengthening the discharging time during a high load demand based on an electricity variation of 50%.
Some of the metrics are blocked by your
consent settings
Thermodynamic analysis of a proton conducting SOFC integrated system fuelled by different renewable fuels
(2021-03-19)
Saebea, Dang
;
Arpornwichanop, Amornchai
;
Patcharavorachot, Yaneeporn
This work proposes a power generation system consisting of steam reformer and SOFC–H+ fuelled by different types of fuel, i.e., ethanol, glycerol and biogas. The performance analysis of integrated system is performed based on thermodynamic calculation through Aspen Plus simulator. The total of the Gibbs free energy minimization is used to determine product composition at equilibrium. The electrochemical model not only considers all voltage losses but also includes the effect of current leakage as a result from the electrolyte used. Considering the operating condition of steam reformer, it is found that the gas product contains the highest amount of hydrogen without the carbon formation when reformer is operated at 973 K with steam to carbon ratio of 1. In addition, the simulation results show that the SOFC–H+ operated at 973 K and 1 A/cm2 can provide a suitable compromise between system performances and exhaust gas composition. The use of glycerol reformate has the highest cell and system efficiencies and fuel utilization compared to the others. In addition, the integrated system fuelled by glycerol can release low CO amount whereas there is more heat provided to the surrounding. Therefore, it can be concluded that glycerol is suitable renewable fuel for SOFC–H+ integrated system.
Some of the metrics are blocked by your
consent settings
Performance analysis of direct steam reforming of methane in SOFC with SDC-based electrolyte
(2020-02-01)
Saebea, D.
;
Authayanun, S.
;
Patcharavorachot, Y.
This work aims to study on the performance of the SDC-based SOFC with a direct internal reforming of methane at lower temperature in the range of 600–750 ºC. The model of SDC-based SOFC with direct internal reforming mode is simulated and validated. The predicted results are in a good agreement with experimental data. The simulated results indicate that the molar flow rate of the hydrogen produced from the methane steam reforming reaction is higher as an increasing temperature. Moreover, the cathode activation overpotential is obviously reduced. Thus, the increase of temperature from 600 to 700 °C can enhance the average power density of SOFC from 0.19 to 0.42 A/m2.
Some of the metrics are blocked by your
consent settings
Performance assessment of a hybrid solid oxide and molten carbonate fuel cell system with compressed air energy storage under different power demands
(2020-01-01)
Jienkulsawad, Prathak
;
Saebea, Dang
;
Patcharavorachot, Yaneeporn
;
Arpornwichanop, Amornchai
As electricity demand can vary considerably and unpredictably, it is necessary to integrate energy storage with power generation systems. This study investigates a solid oxide and molten carbonate fuel cell system integrated with a gas turbine (GT) for power generation. The advanced adiabatic compressed air energy storage (AA-CAES) system is designed to enhance the system flexibility. Simulations of the proposed power system are performed to demonstrate the amount of power that can supply to the loads during normal and peak modes of operation under steady-state conditions. The pressure ratios of the GT and AA-CAES and the additional air feed are used to design the system and analyze the system performance. The results show that a small additional air feed to the GT is certainly required for the hybrid system. The GT pressure ratio of 2 provides a maximum benefit. The AA-CAES pressure ratio of 5 is recommended to spare some air in the storage and minimize storage volume. Moreover, implementation of the GT and AA-CAES into the integrated fuel cell system allows the system to cope with the variations in power demand.
Some of the metrics are blocked by your
consent settings
Performance Evaluation of Solid Oxide Fuel Cell Coupling to Biogas Tri-reforming with Installation of Hydrogen-Selective Membrane Separator
(2020-01-01)
Saebea, D.
;
Soisuwan, S.
;
Patcharavorachot, Y.
Due to high CO<inf>2</inf> composition in biogas, hydrogen concentration produced from the biogas reforming process is low, which has negative effect on the SOFC efficiency. Therefore, aims of this study are to improve and analyze the performance of solid oxide fuel cell (SOFC) integrated with hydrogen production from tri-reforming process of biogas coupling to hydrogen-selective membrane separator. The simulation results show that the increase of pressure increases the hydrogen separation in Pd/Ag membrane separator. The Pd/Ag membrane separator can separate hydrogen of 47.5 %, at 8 bar. When comparing the integrated system of SOFC and biogas tri-reforming without/with installing hydrogen-selective membrane separator, the efficiency of system with coupling to hydrogen-selective membrane separator is higher than that without coupling to hydrogen-selective membrane separator about 13-14.7 %.
Some of the metrics are blocked by your
consent settings
Hydrogen and power generation from supercritical water reforming of glycerol and pressurized SOFC integrated system: Use of different CO2 adsorption process
(2018-09-13)
Patcharavorachot, Yaneeporn
;
Saebea, Dang
;
Authayanun, Suthida
;
Arpornwichanop, Amornchai
The performance analysis of an integrated system of glycerol supercritical water reforming and pressurized SOFC was presented. The use of different CO<inf>2</inf> adsorption processes that include in situ and ex situ processes was compared to determine the suitable process for hydrogen and power generations. The influence of operating condition, e.g., temperature and pressure of reformer, supercritical water to glycerol (S/G) molar ratio, and calcium oxide to glycerol (CaO/G) molar ratio was examined. Then, the electrical performance of each integrated process was considered with respect to the SOFC conditions comprising temperature, pressure, and current density. The simulation results revealed that both processes have same favourable conditions for temperature and pressure operated at 800 °C and 240 atm, respectively. The suitable S/G and CaO/G molar ratios for in situ process are 10 and 2 whereas those for ex situ process are 20 and 1. Under these conditions, maximum hydrogen can be achieved as 87% and 75% for in situ and ex situ processes, respectively. When both integrated processes are operated at the optimal SOFC conditions as 900 °C, 4 atm, and current density of 10,000 A/m2, the SOFC efficiency of 71.56% and 62.12% can provide for in situ and ex situ processes, respectively.
Some of the metrics are blocked by your
consent settings
Analysis of a solid oxide fuel cell and a molten carbonate fuel cell integrated system with different configurations
(2018-01-01)
Jienkulsawad, Prathak
;
Saebea, Dang
;
Patcharavorachot, Yaneeporn
;
Kheawhom, Soorathep
;
Arpornwichanop, Amornchai
A solid oxide fuel cell with internal reforming operation is run at partial fuel utilization; thus, the remaining fuel can be further used for producing additional power. In addition, the exhaust gas of a solid oxide fuel cell still contains carbon dioxide, which is the primary greenhouse gas, and identifying a way to utilize this carbon dioxide is important. Integrating the solid oxide fuel cell with the molten carbonate fuel cell is a potential solution for carbon dioxide utilization. In this study, the performance of the integrated fuel cell system is analyzed. The solid oxide fuel cell is the main power generator, and the molten carbonate fuel cell is regarded as a carbon dioxide concentrator that produces electricity as a by-product. Modeling of the solid oxide fuel cell and the molten carbonate fuel cell is based on one-dimensional mass balance, considering all cell voltage losses. Primary operating conditions of the integrated fuel cell system that affect the system efficiencies in terms of power generation and carbon dioxide utilization are studied, and the optimal operating parameters are identified based on these criteria. Various configurations of the integrated fuel cell system are proposed and compared to determine the suitable design of the integrated fuel cell system.
Some of the metrics are blocked by your
consent settings
Advanced microstructural investigations of AISI 441 early stage oxidation in wet atmosphere
(2017-01-01)
Wongpromrat, Wichitra
;
Parry, Valérie
;
Chandra-Ambhorn, Walairat
;
Chandra-Ambhorn, Somrerk
;
Galerie, Alain
AISI 441 ferritic stainless steel is a good candidate for metallic interconnects in solid oxide fuel cells (SOFCs). The minor elements Ti and Nb are used to stabilize the ferritic matrix and also to reduce creep by a combination of solid solution strengthening and precipitation of intermetallic Laves phase particles along the grain boundaries. However their influence on the oxidation behavior is not well understood. This study focuses on the early stages oxidation (from 4 to 24 h) at 800°C of AISI 441 under 5% H<inf>2</inf>O in O<inf>2</inf>. A relatively smooth micro-crystallized oxide scale and Ti, Nb containing nodules are observed. The internal microstructure of these objects is studied by FIB tomography which allows computing cross sectional views in any direction of interest. FIB study reveals a complex microstructure and a development strongly linked to the presence of niobium and/or titanium in the substrate.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results