Overall Performance of H2/O2 Cycle Power Plants Based on Steam-Methane Reforming

2002 ◽  
Author(s):  
M. Gambini ◽  
M. Vellini
Keyword(s):  
Power Plants ◽  
Fossil Fuels ◽  
Production Systems ◽  
Air Separation ◽  
Methane Reforming ◽  
Fuel Production ◽  
Steam Methane Reforming ◽  
Steam Methane ◽  
Thermodynamic Performance ◽  
Overall Performance

In this paper the overall performance of a H2/O2 cycle has been evaluated. This typology of power plants requires a material and energetic integration with hydrogen and oxygen production systems. The steam-methane reforming, for the hydrogen-rich fuel production, and the cryogenic air separation, for the oxidiser production, have been investigated, quantifying all their thermal and mechanical requirements. At first, the thermodynamic performance of this cycle has been evaluated, considering the presence of incondensable gases, owing to the processes that provide H2 from fossil fuels and O2 from air. Then, the power plant has been integrated with the oxidiser and fuel production plants as well as with the fuel compression section. Including all the material and energetic flows, the overall performance has been evaluated. The final result is not very encouraging: in fact, even if the H2/O2 cycle has relevant thermodynamic performance if the energetic requirements for oxygen and hydrogen productions are neglected — the efficiency is over 62% —, the overall performance of H2/O2 cycle power plants based on steammethane reforming is very low — the net efficiency attains only the 26%.

Comparative Analysis of Advanced H2/Air Cycle Power Plants Based on Different Hydrogen Production Systems From Fossil Fuels

2004 ◽  
Author(s):  
M. Gambini ◽  
M. Vellini
Keyword(s):  
Hydrogen Production ◽  
Power Plants ◽  
Fossil Fuels ◽  
Coal Gasification ◽  
Fossil Fuel ◽  
H2 Production ◽  
Combined Cycle ◽  
Methane Reforming ◽  
Steam Methane Reforming ◽  
Steam Methane

In this paper two options for H2 production by means of fossil fuels are presented, evaluating their performance when integrated with advanced H2/air cycles. The investigation has been developed with reference to two different schemes, representative both of consolidated technology (combined cycle power plants) and of innovative technology (a new advance mixed cycle, named AMC). The two methods, here considered, to produce H2 are: • coal gasification: it permits transformation of a solid fuel into a gaseous one, by means of partial combustion reactions; • steam-methane reforming: it is the simplest and potentially the most economic method for producing hydrogen in the foreseeable future. These hydrogen production plants require material and energy integrations with the power section, and the best connections must be investigated in order to obtain good overall performance. The main results of the performed investigation are quite variable among the different H2 production options here considered: for example the efficiency value is over 34% for power plants coupled with coal decarbonization system, while it is in a range of 45–48% for power plants coupled with natural gas decarbonization. These differences are similar to those attainable by advanced combined cycle power plants fuelled by natural gas (traditional CC) and coal (IGCC). In other words, the decarbonization of different fossil fuels involves the same efficiency penalty related to the use of different fossil fuel in advanced cycle power plants (from CC to IGCC for example). The CO2 specific emissions depend on the fossil fuel type and the overall efficiency: adopting a removal efficiency of 90% in the CO2 absorption systems, the CO2 emission reduction is 87% and 82% in the coal gasification and in the steam-methane reforming respectively.

Advanced Mixed Cycles Based on Steam-Methane Reforming and Air Blown Combustion

2003 ◽  
Author(s):  
M. Gambini ◽  
M. Vellini
Keyword(s):  
Carbon Dioxide Emissions ◽  
Power Plants ◽  
H2 Production ◽  
Combined Cycle ◽  
Methane Reforming ◽  
Production Plant ◽  
Fuel Gas ◽  
Steam Methane Reforming ◽  
Steam Methane ◽  
Overall Performance

In this paper the overall performance of a new advanced mixed cycle (AMC), fed by hydrogen-rich fuel gas, has been evaluated. Obviously, hydrogen must be produced and here we have chosen the steam-methane reforming for its production, quantifying all the thermal and electric requirements. At first, the thermodynamic performance of this cycle has been investigated in comparison with that attainable by combined cycle power plants (CC). Then, the power plants have been integrated with the fuel production system. Including all the material and energetic flows, the overall performance has been evaluated. The main result of the performed investigation is that, while the two power plants attain the same efficiency level without H2 production requirements (about 56% for AMC and 55.8% for CC), the AMC power plant achieves a net electric efficiency of about 48% when integrated with H2 production plant: it is about 3 points higher than the efficiency evaluated for the CC equipped with the same H2 production plant (about 45%). The final carbon dioxide emissions are about 0.0742 and 0.079 kg/kWh for AMC and CC respectively.

Natural Gas Decarbonisation Technologies for Advanced Power Plants

2006 ◽  
Author(s):  
Marco Gambini ◽  
Michela Vellini
Keyword(s):  
Power Plant ◽  
Natural Gas ◽  
Partial Oxidation ◽  
Power Plants ◽  
H2 Production ◽  
Combined Cycle ◽  
Methane Reforming ◽  
Steam Methane Reforming ◽  
Steam Methane ◽  
Percentage Points

In this paper two options for H2 production, by means of natural gas, are presented and their performances are evaluated when they are integrated with advanced H2/air cycles. In this investigation two different schemes have been analysed: an advanced combined cycle power plant (CC) and a new advanced mixed cycle power plant (AMC). The two methods for producing H2 are as follows: • steam methane reforming: it is the simplest and potentially the most economic method for producing hydrogen in the foreseeable future; • partial oxidation of methane: it could offer an energy advantage because this method reduces energy requirement of the reforming process. These hydrogen production plants require material and energetic integrations with power section and the best interconnections must be investigated in order to obtain good overall performance. With reference to thermodynamic and economic performance, significant comparisons have been made between the above introduced reference plants. An efficiency decrease and an increase in the cost of electricity has been obtained when power plants are equipped with a natural gas decarbonisation section. The main results of the performed investigation are quite variable among the different H2 production technologies here considered: the efficiency decreases in a range of 5.5 percentage points to nearly 10 for the partial oxidation of the natural gas and in a range of 8.8 percentage points to over 12 for the steam methane reforming. The electricity production cost increases in a range of about 41–42% for the first option and in a range of about 34–38% for the second one. The AMC, coupled with partial oxidation, stands out among the other power plant solutions here analysed because it exhibits the highest net efficiency and the lowest final specific CO2 emission. In addition to this, economic impact is favourable when AMC is equipped with systems for H2 production based on partial oxidation of natural gas.

Natural Gas Decarbonization Technologies for Advanced Power Plants

2007 ◽  
Vol 129 (4) ◽  
pp. 1114-1124 ◽  
Author(s):  
Marco Gambini ◽  
Michela Vellini
Keyword(s):  
Power Plant ◽  
Natural Gas ◽  
Partial Oxidation ◽  
Power Plants ◽  
H2 Production ◽  
Combined Cycle ◽  
Methane Reforming ◽  
Steam Methane Reforming ◽  
Steam Methane ◽  
Percentage Points

In this paper two options for H2 production, by means of natural gas, are presented and their performances are evaluated when they are integrated with advanced H2/air cycles. In this investigation two different schemes have been analyzed: an advanced combined cycle power plant (CC) and a new advanced mixed cycle power plant (AMC). The two methods for producing H2 are as follows: (1) steam methane reforming: it is the simplest and potentially the most economic method for producing hydrogen in the foreseeable future; and (2) partial oxidation of methane: it could offer an energy advantage because this method reduces the energy requirement of the reforming process. These hydrogen production plants require material and energetic integrations with power section and the best interconnections must be investigated in order to obtain good overall performance. With reference to thermodynamic and economic performance, significant comparisons have been made between the above introduced reference plants. An efficiency decrease and an increase in the cost of electricity has been obtained when power plants are equipped with a natural gas decarbonization section. The main results of the performed investigation are quite variable among the different H2 production technologies here considered: the efficiency decreases in a range of 5.5 percentage points to nearly 10 for the partial oxidation of the natural gas and in a range of about 9 percentage points to over 12 for the steam methane reforming. The electricity production cost increases in a range of about 41–42% for the first option and in a range of about 34–38% for the second one. The AMC, coupled with partial oxidation, stands out among the other power plant solutions here analyzed because it exhibits the highest net efficiency and the lowest final specific CO2 emission. In addition to this, economic impact is favorable when AMC is equipped with systems for H2 production based on partial oxidation of natural gas.

scholarly journals Sulfur Tolerance of Noble Metal Catalysts for Steam Methane Reforming

2017 ◽  
Vol 60 (3) ◽  
pp. 137-145 ◽  
Author(s):  
Fumihiro Watanabe ◽  
Ikuko Kaburaki ◽  
Naohiro Shimoda ◽  
Akira Igarashi ◽  
Shigeo Satokawa
Keyword(s):  
Noble Metal ◽  
Metal Catalysts ◽  
Methane Reforming ◽  
Sulfur Tolerance ◽  
Steam Methane Reforming ◽  
Noble Metal Catalysts ◽  
Steam Methane
Sign in / Sign up

Export Citation Format

Share Document