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Presentation

Experimental and Computational Study for Reduction of NOx Emissions in the Ammonia / Methane Co-Combustion in a 10 KW Furnace

Ryuichi Murai Ryohei Omori Takahiro Kitano Hidetaka Higashino Noriaki Nakatsuka Fumiteru Akamatsu Yuya Yoshizuru Jun Hayashi

There are severe issues on increasing amount of carbon dioxide (CO2) emission in the world. Many studies are devoted to alternative fuels. One of promising candidates is the utilization of ammonia which is zero emission of CO2, a hydrogen energy carrier, and also can be burned directly as a fuel. For direct combustion of ammonia in industrial furnaces, there were two issues which were weaker radiative heat flux and a huge amount of NOx emission compared with the combustion of methane. We already have reported [1] the solution of the former issue by using the oxygen enriched combustion. The objective…

Presentation

NH3 / N2 / O2 Non-Premixed Flame in a 10 kW Experimental Furnace – Characteristics of Radiative Heat Transfer

Ryuichi Murai Ryohei Omori Ryuki Kano Yuji Tada Hidetaka Higashino Noriaki Nakatsuka Jun Hayashi Fumiteru Akamatsu Kimio Iino Yasuyuki Yamamoto Yoshiyuki Hagiwara

There are severe issues on increasing amount of carbon dioxide (CO2) emission in the world. Many studies are devoted on alternative fuels. One of superior candidates is the utilization of hydrogen energy which can realize a low-carbon and hydrogen-based society. Ammonia might play an important role which is zero emission of CO2, and is useful for hydrogen energy carrier as a clean energy. Additionally, ammonia is an easily-liquefiable fuel with pressure of about 0.86 MPa and temperature of 293 K. Commercially, ammonia is produced in large quantity by the Haber–Bosch process. It is also to be produced by using catalyst…

Presentation

Effects of the Thickness of the Burner Rim, the Velocities of Fuel and Air on Extinction Limit of Ammonia Coaxial Jet Diffusion Flame

Yohei Ishikawa Jun Hayashi Hiroyuki Takeishi Takahiro Okanami Kimio Iino Fumiteru Akamatsu Yasuyuki Yamamoto Yoshiyuki Hagiwara

Ammonia is regarded as one of the alternative fuels because CO2 doesn’t emit during the combustion process of ammonia. Ammonia also has advantages in storage and transportation. In addition, ammonia has a potential to be a “hydrogen carrier” because of high amount of hydrogen content. However, there are several combustion related problems such as the low flammability, the low radiative power and the high NOx formation. To use ammonia as a fuel, therefore, it is necessary to understand the fundamental phenomena of the combustibility of the ammonia such as laminar burning velocity, strength of the radiation and extinction limit. Since…

Presentation

Detailed Observation of Coal-Ammonia Co-Combustion Processes

Noriaki Nakatsuka Junpei Fukui Kazuki Tainaka Hidetaka Higashino Jun Hayashi Fumiteru Akamatsu

Coal-fired power generation is supplying about 30% of the world’s primary energy. Almost all of coal-fired power plants in Japan employ the pulverized coal combustion method. In the pulverized coal combustion, coal is pulverized into a powder of several tens of microns. This method enables to burn coal effectively because of the large surface to volume ratio. Pulverized coal particles are supplied to the actual boilers with primary air whose Air/Coal ratio (mass flow rate of primary air/mass flow rate of pulverized coal) is set to 2.0. Co-combustion of coal with ammonia has been studied with the aim of reducing…

Presentation

Characteristics of Ammonia / N2 / O2 Laminar Premixed Flame in Oxygen-enriched Condition

Hiroyuki Takeishi Jun Hayashi Shota Kono Kimio Iino Fumiteru Akamatsu

The problems of ammonia fuel are a low combustion qualities compared with the combustion qualities of hydrocarbon fossil fuels. In this study, the laminar burning velocity was used as the indicator of the combustion quality. Since the laminar burning velocity of ammonia fuel is low compared with that of other fossil fuels, it is necessary to increase the combustion quality in order to utilize the ammonia as an alternative fuel in conventional combustion systems. In this study, the oxygen-enriched combustion was applied to an ammonia/N2/O2 premixed flame for achieving higher burning velocity. The effects of the oxygen-enriched combustion on the…