Internal Reforming SOFC System for Flexible Coproduction of Hydrogen and Power

2005 ◽  
Author(s):  
Kas Hemmes ◽  
Anish Patil ◽  
Nico Woudstra
Keyword(s):  
Fuel Cell ◽  
Hydrogen Production ◽  
Natural Gas ◽  
Total System ◽  
Flow Sheet ◽  
Content Increase ◽  
Fuel Utilization ◽  
Production Mode ◽  
Internal Reforming ◽  
Production Of Hydrogen

In the framework of the project Greening of Gas, in which the feasibility of mixing hydrogen into the natural gas network in the NL is studied, we are exploring alternative hydrogen production methods. Fuel cells are usually only seen as devices that convert hydrogen into power and heat. It is less well known that these electrochemical energy converters can produce hydrogen, or form an essential component in systems for co-production of hydrogen and power. Co-production of hydrogen and power from NG in an Internal reforming fuel cell (IR FC) is worked out by flow sheet calculations on an Internal reforming Solid Oxide fuel cell (IR-SOFC) system. It is shown that the system can operate in a wide range of fuel utilization values at least from 60% representing highest hydrogen production mode to 95% corresponding to ‘normal’ fuel cell operation mode. For the atmospheric pressure system studied here hydrogen and CO content increase up to 22.6 and 13.5 % respectively at a fuel utilization of 60%. Total system efficiency (power + H2/CO) is increasing significantly at lower fuel utilization and can reach 94 %. Our study confirms that the calculations of Vollmar et al1) on an IR-SOFC stack also hold for a complete FC system. Notably that paradoxically a system with the same fuel cell stack when switched to hydrogen production mode can yield more power in addition to the H2 and CO produced. This is because the hydrogen production mode allows for operation at high current and power densities. The same system can double its power output (e.g. from 1.26 MW to 2.5 MW) while simultaneously increasing the H2 /CO output to 3.1MW). Economics of these systems is greatly improved. These systems can also be considered for hydrogen production for the purpose of mixing it with natural gas in the natural gas grid in order to reduce CO2 emissions at the end users, because of the ability to adopt the system rapidly to fluctuations in natural gas/hydrogen demand.

Flexible Coproduction of Hydrogen and Power Using Internal Reforming Solid Oxide Fuel Cells System

2008 ◽  
Vol 5 (4) ◽  
Author(s):  
Kas Hemmes ◽  
Anish Patil ◽  
Nico Woudstra
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Hydrogen Production ◽  
Natural Gas ◽  
Cell System ◽  
Solid Oxide ◽  
Flow Sheet ◽  
Oxide Fuel ◽  
Internal Reforming ◽  
Wide Range

Within the framework of the Greening of Gas project, in which the feasibility of mixing hydrogen into the natural gas network in the Netherlands is studied, we are exploring alternative hydrogen production methods. Fuel cells are usually seen as the devices that convert hydrogen into power and heat. It is less well known that these electrochemical energy converters can produce hydrogen, or form an essential component in the systems for coproduction of hydrogen and power. In this paper, the coproduction of hydrogen-rich syngas (that can be converted into hydrogen) and power from natural gas in an internal reforming fuel cell is worked out by flow sheet calculations on an internal reforming solid oxide fuel cell system. The goal of this paper is to study the technical feasibility of such a system and explore its possibilities and limitations for a flexible coproduction. It is shown that the system can operate in a wide range of fuel utilization values at least down to 60% representing highest hydrogen production mode up to 95% corresponding to standard FC operation mode.

Performance Comparison of Internal and External Reforming for Hybrid SOFC-GT Applications by Using 1D Real-Time Fuel Cell Mode

2019 ◽  
Author(s):  
Hao Chen ◽  
Chen Yang ◽  
Nana Zhou ◽  
Nor Farida Harun ◽  
David Tucker
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Natural Gas ◽  
Solid Oxide Fuel Cells ◽  
Real Time ◽  
Hybrid System ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Fuel Utilization ◽  
Internal Reforming

Abstract Solid oxide fuel cells integrated with gas turbine (SOFC-GT) systems are considered among the most promising power generation units, not only because of the high efficiency, low emissions and carbon capture ability, but also the flexibility to use different kinds of fuels such as natural gas, syngas and biogas directly. In the case of natural gas, Previous researches have demonstrated that solid oxide fuel cells possess the ability to utilize natural gas directly by reforming it inside the anode because of the high operating temperature. But the major problem of internal reforming is that it increases the temperature gradient at the leading edge of fuel cell which may lead to high thermal stress and damage the cells. On the other side, external reforming requires an additional reformer outside of fuel cell, which may increase the investment costs. Also, the amount of air needed to cool the fuel cell is doubled, compared with internal reforming. A full comparison between internal reforming and external reforming of the pressurized SOFC is needed for the hybrids application. In this paper, a real time equilibrium reformer model based on minimization of Gibbs free energy was built to couple with 1D real time solid oxide fuel cell model. An internal on-anode reforming SOFC stack configuration for hybrid SOFC-GT system application was compared with external reforming configurations with 800K, 900K and 1000K reforming temperatures. The results show that internal reforming provides better performance of SOFC stack in the case of high fuel utilization. However, the external reforming showed a higher stack efficiency and smaller stack size compared with on-anode reforming when keeping a relatively lower SOFC stack fuel utilization, necessarily for high hybrid efficiency. Results indicated that external and internal reforming of fuel needs to be optimized depending on different design conditions of the entire hybrid system in terms of efficiency and investment cost. This paper shows that the hybrid system provides the opportunities for thermal integration on performance and efficiency improvement over fuel cell anode reforming.

scholarly journals Experimental Demonstration and Validation of Hydrogen Production Based on Gasification of Lignocellulosic Feedstock

2018 ◽  
Vol 2 (4) ◽  
pp. 61 ◽  
Author(s):  
Jürgen Loipersböck ◽  
Markus Luisser ◽  
Stefan Müller ◽  
Hermann Hofbauer ◽  
Reinhard Rauch
Keyword(s):  
Hydrogen Production ◽  
Pressure Swing Adsorption ◽  
Production Plant ◽  
Flow Sheet ◽  
Hydrogen Yield ◽  
Fuel Feed ◽  
Worldwide Production ◽  
Lignocellulosic Feedstock ◽  
Production Of Hydrogen ◽  
Pressure Swing

The worldwide production of hydrogen in 2010 was estimated to be approximately 50 Mt/a, mostly based on fossil fuels. By using lignocellulosic feedstock, an environmentally friendly hydrogen production route can be established. A flow sheet simulation for a biomass based hydrogen production plant was published in a previous work. The plant layout consisted of a dual fluidized bed gasifier including a gas cooler and a dust filter. Subsequently, a water gas shift plant was installed to enhance the hydrogen yield and a biodiesel scrubber was used to remove tars and water from the syngas. CO2 was removed and the gas was compressed to separate hydrogen in a pressure swing adsorption. A steam reformer was used to reform the hydrocarbon-rich tail gas of the pressure swing adsorption and increase the hydrogen yield. Based on this work, a research facility was erected and the results were validated. These results were used to upscale the research plant to a 10 MW fuel feed scale. A validation of the system showed a chemical efficiency of the system of 60% and an overall efficiency of 55%, which indicates the high potential of this technology.

Numerical Simulation of an Axisymmetric Ethanol Reforming Reactor for Hydrogen Fuel Cell Applications

2006 ◽  
Author(s):  
Gregory A. Buck ◽  
Hiroyuki Obara
Keyword(s):  
Fuel Cell ◽  
Hydrogen Production ◽  
Autothermal Reforming ◽  
Great Promise ◽  
Hydrogen Fuel Cell ◽  
Hydrogen Fuel ◽  
Gaseous State ◽  
Ethanol Reforming ◽  
Wide Range ◽  
Production Of Hydrogen

Hydrogen fuel cell technology is currently capable of providing adequate power for a wide range of stationary and mobile applications. Nonetheless, the sustainability of this technology rests upon the production of hydrogen from renewable resources. Among the techniques under current study, the chemical reforming of alcohols and other bio-hydrocarbon fuels, appears to offer great promise. In the so called autothermal reforming process, a suitable combination of total and partial oxidation supports hydrogen production from ethanol with no external addition of energy required. Furthermore, the autothermal reforming process conducted in a well insulated reactor, produces temperatures that promote additional hydrogen production through the endothermic steam reforming and the water-gas shift reactions, which may be catalyzed or uncatalyzed, with the added benefit of lowered carbon monoxide concentrations. In this study, an adiabatic ethanol reforming reactor was simulated assuming the reactants to be air (21% O2 and 79% N2) and ethanol (C2H5OH) and the products to be H2O, CO2, CO and H2, with all constituents taken to be in the gaseous state. The air was introduced uniformly through a ring around the side of the reactor and the gaseous ethanol was injected into the center of one end, with products withdrawn from the center of the opposite end, to create an axisymmetric flow field. The gas flows within the reactor were assumed to be turbulent, and the chemical kinetics of a simple four reaction system was assumed to be controlled by turbulent mixing processes. Air and fuel flow rates into the reactor were varied to obtain six different levels of oxidation (air-fuel ratios) while maintaining the same total gaseous mass flow out of the reactor. The numerical results for the reacting flow show that hydrogen production is maximized when the air-fuel ratio on a mass basis is held at approximately 2.8. These findings are in qualitative agreement with observations from previous experimental studies.

Numerical Simulation of an Internal Reforming Solid Oxide Fuel Cell Unit Fueled with Hydrogen-Natural Gas Mixtures

2021 ◽  
Vol MA2021-03 (1) ◽  
pp. 163-163
Author(s):  
Junhua Fan ◽  
Yuqing Wang ◽  
Jixin Shi ◽  
Yixiang Shi ◽  
Haishan Cao ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Fuel Cell ◽  
Natural Gas ◽  
Solid Oxide Fuel Cell ◽  
Gas Mixtures ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Internal Reforming

Hydrogen Production by Solar Reforming of Natural Gas: A Comparison Study of Two Possible Process Configurations

2005 ◽  
Vol 128 (1) ◽  
pp. 16-23 ◽  
Author(s):  
Stephan Möller ◽  
Dario Kaucic ◽  
Christian Sattler
Keyword(s):  
Hydrogen Production ◽  
Natural Gas ◽  
Solar Energy ◽  
Cost Study ◽  
Fuel Savings ◽  
Production Of Hydrogen ◽  
Production Technologies ◽  
The Cost ◽  
Favorable Conditions ◽  
Renewable Hydrogen

Solar steam reforming of natural gas (NG) is a possibility to lower the cost for introducing renewable hydrogen production technologies to the market by a combination of fossil fuel and solar energy. It comprises the production of hydrogen from NG and steam that acts as a chemical storage for hydrogen and solar energy as the renewable energy source to heat up the system and set free the hydrogen. Using the solar reformer technology fuel savings of up to 40% compared to a conventional plant are expected. The CO2 emissions can be reduced accordingly. The cost study shows that hydrogen produced by solar reforming might cost between 4.5 and 4.7ct€∕kWh (LHV of H2) today. Therefore, it is only about 20% more expensive than conventionally produced hydrogen. Rising prices for NG will result in favorable conditions for the solar technology.

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