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Presentation

Pure Ammonia Combustion Micro Gas Turbine System

Ekenechukwu Chijioke Okafor Osamu Kurata Norihiko Iki Takahiro Inoue Tadahiro Fujitani Yong Fan Takayuki Matsunuma Taku Tsujimura Hirohide Furutani Masato Kawano Keisuke Arai Akihiro Hayakawa Hideaki Kobayashi

To protect against global warming, a massive influx of renewable energy is expected. Although hydrogen is a renewable media, its storage and transportation in large quantity has some problems. Ammonia fuel, however, is a hydrogen energy carrier and carbon-free fuel, and its storage and transportation technology is already established. In the 1960s, development of ammonia combustion gas turbines was abandoned because combustion efficiency was unacceptably low [1]. Recent demand for hydrogen energy carriers has revived the interest in ammonia as fuel [2, 3]. In 2015, ammonia-combustion gas turbine power generation was reported in Japan using a 50-kW class micro gas…

Presentation

Two Stage Ammonia Combustion in a Gas Turbine like Combustor for Simultaneous NO and Unburnt Ammonia Reductions

Akihiro Hayakawa K.D. Kunkuma A. Somarathne Masaaki Tsukamoto Taku Kudo Hideaki Kobayashi

Ammonia is expected not only as a hydrogen energy carrier but also as a carbon free fuel. Recently, ammonia fueled gas turbine combustor was successfully demonstrated. However, large amount of NOx was produced when ammonia burns because ammonia includes nitrogen atom in the ammonia molecule. In addition, unburnt ammonia concentration in exhaust gas also needs to be reduced. In this study, we proposed a combustion concept in order to reduce NO and unburnt ammonia concentrations in the exhaust gas simultaneously in a gas turbine like model swirl combustor. In this concept, two stage (rich – lean) combustion was employed. Two…

Presentation

Development of Low-NOx Combustor of Micro Gas Turbine Firing Ammonia Gas

Osamu Kurata Norihiko Iki Takahiro Inoue Takayuki Matsunuma Taku Tsujimura Hirohide Furutani Masato Kawano Keisuke Arai Ekenechukwu Chijioke Okafor Akihiro Hayakawa Hideaki Kobayashi

A massive influx of renewable energy is required in order to mitigate global warming. Although hydrogen is a renewable media, its storage and transportation in large quantity is difficult. Ammonia, however, is a hydrogen energy carrier, and its storage and transportation technology is already established. Although ammonia fuel combustion was studied in the 1960s in the USA, the development of an ammonia fuel gas turbine had been abandoned because combustion efficiency was unacceptably low [1]. Recent demand for hydrogen energy carrier revives the usage of ammonia fuel. The National Institute of Advanced Industrial Science and Technology (AIST) in Japan, in…

Presentation

Combustion Emissions from NH3 Fuel Gas Turbine Power Generation Demonstrated

Osamu Kurata Norihiko Iki Takahiro Inoue Takayuki Matsunuma Taku Tsujimura Hirohide Furutani Hideaki Kobayashi Akihiro Hayakawa

To protect against global warming, a massive influx of renewable energy is expected. Although H2 is a renewable media, its storage and transportation in large quantity is difficult. NH3 fuel, however, is an H2 energy carrier and carbon-free fuel, and its storage and transportation technology is already established. Although NH3 fuel combustion was studied in the 1960s in the USA, the development of an NH3 fuel gas turbine had been abandoned because combustion efficiency was unacceptably low [1]. Recent demand for H2 energy carrier revives the usage of NH3 fuel, but no one has attempted an actual design setup for…

Presentation

Combustion characteristics of ammonia/air flames for a model swirl burner and an actual gas turbine combustor

Akihiro Hayakawa K.D. Kunkuma A. Somarathne Ekenechukwu Chijioke Okafor Taku Kudo Osamu Kurata Norihiko Iki Hideaki Kobayashi

Ammonia is expected not only as hydrogen energy carrier but also as carbon free fuel. For an industrial use of ammonia combustor, ammonia flame stabilized on a swirl combustor should be clarified. However, in order to realize an ammonia-fueled combustor, there are some issues to be solved, such as a difficulty of flame stabilization and reductions of NOx and ammonia emission. In this study, stabilization and emission characteristics of ammonia / air flames stabilized by a model swirl burner are investigated. The outer and inner diameters of the swirler are 24 mm and 14 mm, respectively, and the swirl number…

Presentation

Power Generation and Flame Visualization of Micro Gas Turbine Firing Ammonia or Ammonia-Methane Mixture

Norihiko Iki Osamu Kurata Takayuki Matsunuma Takahiro Inoue Taku Tsujimura Hirohide Furutani Hideaki Kobayashi Akihiro Hayakawa

A demonstration test with the aim to show the potential of ammonia-fired power plant is planned using a micro gas turbine. 50kW class turbine system firing kerosene is selected as a base model. A standard combustor is replaced to a prototype combustor which enables a bi-fuel supply of kerosene and ammonia gas. Diffusion combustion is employed to the prototype combustor due to its flame stability. 44kW power generation was achieved by 100% heat from ammonia gas. Although NOx concentration in the exhaust gas of ammonia combustion exceeded 500ppm, NOx removal equipment reduced NOx concentration below 10ppm. Over 30kW power generation…

Presentation

Enhancement of reaction and stability of ammonia flames using hydrogen addition and swirling flow

Akihiro Hayakawa Akinori Ichikawa Yoshiyuki Arakawa Taku Kudo Hideaki Kobayashi

Enhancement of reaction and stability of ammonia flames using hydrogen addition and swirling flow Akihiro Hayakawa*, Akinori Ichikawa, Yoshiyuki Arakawa, Taku Kudo and Hideaki Kobayashi, Institute of Fluid Science, Tohoku University

Presentation

Micro Gas Turbine Firing Ammonia

Norihiko Iki Osamu Kurata Takayuki Matsunuma Takahiro Inoue Masato Suzuki Taku Tsujimura Hirohide Furutani Hideaki Kobayashi Akihiro Hayakawa Yoshiyuki Arakawa Masanori Ichikawa

Micro Gas Turbine Firing Ammonia Norihiko Iki*, Osamu Kurata, Takayuki Matsunuma, Takahiro Inoue, Masato Suzuki, Taku Tsujimura and Hirohide Furutani, National Institute of Advanced Industrial Science and Technology (AIST), Fukushima Renewable Energy Institute (FREA); Hideaki Kobayashi, Akihiro Hayakawa, Yoshiyuki Arakawa, Masanori Ichikawa, Institute of Fluid Science, Tohoku University

Presentation

Fundamental Characteristics of Ammonia/Air Premixed Laminar Flames

Akihiro Hayakawa Takashi Goto Rentaro Mimoto Taku Kudo Hideaki Kobayashi

Fundamental flame characteristics must be required for the design of ammonia fueled combustors. However, few studies of ammonia combustion have been conducted. In this study, fundamental ammonia/air premixed laminar flame characteristics, such as NO formation/reduction mechanisms and laminar burning velocity, were experimentally and numerically investigated. NO mole fraction in burned gas from ammonia/air premixed flames were investigated using a stainless-steel nozzle burner. Experiments were conducted at various equivalence ratios and pressures. As a result, NO mole fraction in burned gas reduced with the increase in equivalence ratio and pressure. Formation/reduction mechanisms of NO were numerically investigated. Laminar burning velocity and…