Process simulation of hydrogen production by steam reforming of diluted bioethanol solutions: Effect of operating parameters on electrical and thermal cogeneration by using fuel cells

Hydrogen is currently being widely regarded as a futural energy carrier to reduce carbon emissions and other NOx and SOx pollutants. Many researchers have proved that hydrogen can be efficiently used in solid oxide fuel cells -gas turbine system (SOFC-GT) and molten carbonate fuel cells-gas turbine system (MCFC-GT). Hydrogen production from biomass resources offers the advantage of providing a renewable energy carrier for extensive reduction of the CO2 emission. A secondary steam reforming process which consists of steam reforming of methane and water gas shift was proposed to further convert CH4, CO and other hydrocarbons in biomass pyrolysis gas for promoting hydrogen yield. According to respective reaction mechanism, simulating calculations were carried out in two reforming processes separately. With the favor of PRO/II, the effects of reaction temperature and steam to carbon ratio on hydrogen yield were discussed in details in the steam reforming of methane. A reasonable calculation method was established for simulating the water gas shift process in which the effects of temperature and steam to CO ratio was investigated. The simulation made good results in optimizing reaction conditions for two reformers and predicting the volume rate of all gas components. It is proved by simulation that hydrogen-rich gas with >68 mol% H2 could be produced, and the hydrogen yield could reach 48.18 mol H2/(Kg Biomass) and 45.85 mol/(Kg Biomass) respectively when using corn straw and rice husk as feedstock. The experiment data from a related reference was adopted to prove the reasonability of the simulation results which could show the feasibility of secondary steam reforming process, as well as provide good references for practical process operation.

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Methanol as a High Purity Hydrogen Source for Fuel Cells: A Brief Review of Catalysts and Rate Expressions

Chemical and Process Engineering ◽

10.1515/cpe-2017-0012 ◽

2017 ◽

Vol 38 (1) ◽

pp. 147-162 ◽

Cited By ~ 3

Author(s):

Maria Madej-Lachowska ◽

Maria Kulawska ◽

Jerzy Słoczyński

Keyword(s):

Carbon Monoxide ◽

Fuel Cells ◽

Hydrogen Production ◽

Steam Reforming ◽

Kinetic Equations ◽

Environmental Benefits ◽

Production Methods ◽

Steam Reforming Of Methanol ◽

Fuel Source ◽

Oxidation Of Carbon Monoxide

Abstract Hydrogen is the fuel of the future, therefore many hydrogen production methods are developed. At present, fuel cells are of great interest due to their energy efficiency and environmental benefits. A brief review of effective formation methods of hydrogen was conducted. It seems that hydrogen from steam reforming of methanol process is the best fuel source to be applied in fuel cells. In this process Cu-based complex catalysts proved to be the best. In presented work kinetic equations from available literature and catalysts are reported. However, hydrogen produced even in the presence of the most selective catalysts in this process is not pure enough for fuel cells and should be purified from CO. Currently, catalysts for hydrogen production are not sufficiently active in oxidation of carbon monoxide. A simple and effective method to lower CO level and obtain clean H2 is the preferential oxidation of monoxide carbon (CO-PROX). Over new CO-PROX catalysts the level of carbon monoxide can be lowered to a sufficient level of 10 ppm.

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Reactor design and catalysts testing for hydrogen production by methanol steam reforming for fuel cells applications

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2015.11.047 ◽

2016 ◽

Vol 41 (2) ◽

pp. 924-935 ◽

Cited By ~ 31

Author(s):

Francisco Vidal Vázquez ◽

Pekka Simell ◽

Jari Pennanen ◽

Juha Lehtonen

Keyword(s):

Fuel Cells ◽

Hydrogen Production ◽

Steam Reforming ◽

Reactor Design ◽

Methanol Steam Reforming

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Possibilities of Upgrading Solid Underutilized Lingo-cellulosic Feedstock (Carob Pods) to Liquid Bio-fuel: Bio-ethanol Production and Electricity Generation in Fuel Cells - A Critical Appraisal of the Required Processes

Studies in Engineering and Technology ◽

10.11114/set.v4i1.2170 ◽

2017 ◽

Vol 4 (1) ◽

pp. 25 ◽

Cited By ~ 3

Author(s):

John Vourdoubas ◽

Vasiliki K. Skoulou

Keyword(s):

Power Generation ◽

Fuel Cells ◽

Hydrogen Production ◽

Ethanol Production ◽

Steam Reforming ◽

Electricity Generation ◽

Fossil Fuels ◽

Cost Effective ◽

Ethanol Fuel ◽

Steam Reforming Of Ethanol

The exploitation of rich in sugars lingo-cellulosic residue of carob pods for bio-ethanol and bio-electricity generation has been investigated. The process could take place in two (2) or three (3) stages including: a) bio-ethanol production originated from carob pods, b) direct exploitation of bio-ethanol to fuel cells for electricity generation, and/or c) steam reforming of ethanol for hydrogen production and exploitation of the produced hydrogen in fuel cells for electricity generation. Surveying the scientific literature it has been found that the production of bio-ethanol from carob pods and electricity fed to the ethanol fuel cells for hydrogen production do not present any technological difficulties. The economic viability of bio-ethanol production from carob pods has not yet been proved and thus commercial plants do not yet exist. The use, however, of direct fed ethanol fuel cells and steam reforming of ethanol for hydrogen production are promising processes which require, however, further research and development (R&D) before reaching demonstration and possibly a commercial scale. Therefore the realization of power generation from carob pods requires initially the investigation and indication of the appropriate solution of various technological problems. This should be done in a way that the whole integrated process would be cost effective. In addition since the carob tree grows in marginal and partly desertified areas mainly around the Mediterranean region, the use of carob’s fruit for power generation via upgrading of its waste by biochemical and electrochemical processes will partly replace fossil fuels generated electricity and will promote sustainability.

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