• Applied Chemistry for Engineering
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• v.31 no.1
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• pp.1-6
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• 2020

Hydrogen production from biogas has received consistent attention due to the great potential to solve simultaneously the issues of energy demands and environmental problems. Practically, biomethane produced by purification/upgrading of biogas can be a good alternative to the natural gas which is a main reactant for a steam methane reforming process. Judging from the economic and environmental impacts, however, the steam biogas and dry reforming are considered to be more effective routes for hydrogen production because both processes do not require the carbon dioxide elimination step. Herein, we highlight recent studies of hydrogen production via reforming processes using biogas and effective applications for earlier commercialization.

• New & Renewable Energy
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• v.20 no.1
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• pp.126-134
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• 2024

Biogas, composed mainly of methane (CH₄) and carbon dioxide (CO₂), is a renewable gas that can serve as an alternative energy source. In this study, we developed a new microwave reformer and analyzed its reforming characteristics. We observed that higher temperatures of the microwave receptor led to increased reforming efficiency. By supplying appropriate amounts of methane and steam, we could prevent carbon generated from the thermal decomposition reaction of carbon dioxide from depositing on the catalytic active layer, thus avoiding the inhibition of catalytic activity. Hydrogen generation was enhanced when maintaining the biogas ratio and steam supply at adequate levels. Increasing the SiC ratio in the receptor improved the uniformity of temperature distribution and growth rate, resulting in higher conversion rates of the reforming process.

• Transactions of the Korean hydrogen and new energy society
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• v.29 no.1
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• pp.1-10
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• 2018

The amount of biogas increases as the amount of organic waste increases. Recently, biogas from organic waste have been made much efforts to utilize as a energy. In particular, the concentration of $CH_4$ and $CO_2$ generated from sewage sludge and livestock manure treatment are 60-70% and 30-35%, and $CH_4$ and $CO_2$ generated from food wastes are 60-80% and 20-40%. In case of landfill gas, $CH_4$ and $CO_2$ have a concentration of 40-60% and 40-60% respectively. Therefore, in order to use the biogas more widely, it is necessary to convert the biogas to methanol, LNG or DME. In this study, experiments were conducted to produce hydrogen and carbon monoxide through various biogas reforming reactions on $Ni/Ce-ZrO_2/Al2O3$ catalysts. The experiment of synthetic gas synthesis was carried out on a wide concentrations of methane and carbon dioxide, which were the major constituents of biogas from various organic wastes. The effect of $(O_2+CO_2)/CH_4$ (=R') on the yields of hydrogen and carbon monoxide, the conversion rate of methane and carbon dioxide was investigated. Also simulation for syngas synthesis on the $CO_2$ reforming of $CH_4$ was computed by employing total Gibbs free energy minimization method using PRO/II simulator, and compared with the experimental results on wet and dry reforming reaction of biogas.

• Transactions of the Korean hydrogen and new energy society
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• v.23 no.3
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• pp.236-242
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• 2012

This study has been carried out the experiment for the possibility of biogas reforming using waste heat. The source of this waste heat is the exhaust gas from a small-sized gas engine generator. For recovering the waste heat, Two-stage heat exchanger is manufactured. The two-stage heat exchanger is composed of a heat exchanger for the exhaust gas and a heat exchanger for the water. This two-stage heat exchanger is used for reforming the biogas by means of on-site hydrogen production at the small-sized gas engine generator. The two-stage heat exchanger is coupled with the biogas reformer which is a kind of catalytic reformer. To confirm a heat recovery efficiency of the two-stage heat exchanger, temperature differences of inlet and outlet locations are measured. Also, the variations of syngas concentrations with various biogas flow rates are investigated. As a result using manufactured two-stage heat exchanger, the biogas can be reformed from waste heat recovery. This experiment suggests that the exhaust gas heat exchanger is available for reforming the biogas.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.1
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• pp.42-49
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• 2010

Increasing environmental concerns regarding the use of fossil fuels and global wanning have prompted researcher to investigate alternative fuels. The purpose of this study is to investigate the syngas production by biogas reforming using a compression spark ignition engine. The parametric screening studies were carried out according to the variations of oxygen enrichment rate, biogas $CO_2$ ratio, intake gas temperature, and engine revolution. When the oxygen enrichment rate and input gas temperature increased, hydrogen and carbon monoxide were increased. But the biogas $CO_2$ ratio and engine revolution increased, the syngas were reduced. For the reforming of methane 100% only, generation of hydrogen and carbon monoxide was 58% and 17%, respectively. However when the biogas $CO_2$ ratio was 40%, hydrogen and carbon monoxide concentration were about 20% each.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.1
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• pp.100-108
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• 2011

The use of biogas as an energy source reduces the chance of possible emission of two greenhouse gases, $CH_4$ and $CO_2$, into the atmosphere at the same time. Its nature of being a reproducible energy source makes its use even more attractive. This research if for the hydrogen production through the steam reforming of the biogas. The biogas utilized 3D-IR matrix burner in which the surface combustion is applied. The nickel catalyst was used inside a reformer. Parametric screening studies were achieved as Steam/Carbon ratio, biogas component ratio, Space velocity and Reformer temperature. When the condition of Steam/Carbon ratio, $CH_4/CO_2$ ratio, Space velocity and Refomer temperature were 3.25, 60%:40%, 19.32L/$g{\cdot}hr$ and $700^{\circ}C$ respectively, the hydrogen concentration and methane conversion rate were showed maximum values. Under the condition mentioned above, $H_2$ concentration was 73.9% and methane conversion rate was 98.9%.

• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.528-534
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• 2006

The purpose of this paper is to investigate the optimal operating condition for the hydrogen production by biogas reforming using the plasmatron induced thermal plasma. The component ratio of biogas($CH_4/CO_2$) produced by anaerobic digestion reactor were 1.03, 1.28, 2.12, respectively. And the reforming experiment was performed. To improve hydrogen production and methane conversion rates, parametric screening studies were conducted, in which there are the variations of biogas flow ratio(biogas/TFR: total flow rate), vapor flow ratio($H_2O/TFR$: total flow rate) and input power. When the variations of biogas flow ratio, vapor flow ratio and input power were 0.32~0.37, 0.36~0.42, and 8 kW, respectively, the methance conversion reached its optimal operating condition, or 81.3~89.6%. Under the condition mentioned above, the wet basis concentrations of the synthetic gas were H2 27.11~40.23%, CO 14.31~18.61%. The hydrogen yield and the conversion rate of energy were 40.6~61%, 30.5~54.4%, respectively, the ratio of hydrogen to carbon monoxide($H_2/CO$) was 1.89~2.16.

• Journal of Energy Engineering
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• v.20 no.3
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• pp.252-258
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• 2011

Nickel fiber mat was investigated as a potential structured catalyst for steam reforming of biogas in the temperature range of $600-700^{\circ}C$. The activity of as-received catalyst was very low owing to the smooth surface of fibers. Pretreatment of the catalyst by oxidation followed by reduction under methane partial oxidation condition significantly improved the catalytic activity, although degradation of the activity was found during the reaction due to oxidation and sintering. This deactivation was retarded by supplying additional hydrogen in the inlet gases or by coating $CeO_2$ over the catalyst surfaces.

• Transactions of the Korean hydrogen and new energy society
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• v.30 no.2
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• pp.111-118
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• 2019

Greenhouse gas emissions have a profound effect on global warming. Various environmental regulations have been introduced to reduce the emissions. The largest amount of greenhouse gases, including carbon dioxide, is produced in the steel industry. To decrease carbon dioxide emission, hydrogen-based iron oxide reduction, which can replace carbon-based reduction has received a great attention. Iron production generates various by-product gases, such as cokes oven gas (COG), blast furnace gas (BFG), and Linz-Donawitz gas (LDG). In particular, COG, due to its high concentrations of hydrogen and methane, can be reformed to become a major source of hydrogen for reducing iron oxide. Nevertheless, continuous COG cannot be supplied under actual operation condition of steel industry. To solve this problem, this study proposed to use two alternative COG-based fuel mixtures; one with natural gas and the other with biogas. Reforming study on two types of mixed gas were carried out to evaluate catalyst performance under a variety of operating conditions. In addition, methane conversion and product composition were investigated both theoretically and experimentally.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.12
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• pp.840-846
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• 2012

Global climate changes caused by $CO_2$ emissions are currently debated around the world; green sources of energy are being sought as alternatives to replace fossil fuels. The sustainable use of biogas for energy production does not contribute to $CO_2$ emission and has therefore a high potential to reduce them. Catalytic steam reforming of a model biogas ($CH_4:CO_2$ = 60%:40%) is investigated to produce $H_2$-rich synthesis gas. The biogas utilized 3D-IR matrix burner in which the surface combustion is applied. The ruthenium catalyst was used inside a reformer. Parametric screening studies were achieved as Steam/Carbon ratio, biogas component ratio, Space velocity and Reformer temperature. When the condition of Steam/Carbon ratio, $CH_4/CO_2$ ratio, Space velocity and Refomer temperature were 3.25, 60% : 40%, $14.7L/g{\cdot}hr$ and $550^{\circ}C$ respectively, the hydrogen concentration and methane conversion rate were showed maximum values. Under the condition mentioned above, $H_2$ yield, $H_2$/CO ratio, CO selectivity and energy efficiency were 0.65, 2.14, 0.59, 51.29%.