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

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…

Paper

Efficient and Clean Combustion of Ammonia-Hydrogen-Air Mixtures

Based on its well-known merits ammonia has been gaining special attention as a potential renewable energy carrier which can be replaced in power generation systems. Considering its low flame speed and its potential for producing fuel NOx as the main challenges of combusting ammonia, flame stability, combustion efficiency, and NOx formation are experimentally investigated. Focus is on premixed ammonia-hydrogen-air flames with high mixture fractions of ammonia (60-90% by volume) under standard temperature and pressure conditions. We introduce silicon-carbide (SiC) porous block as a practical and effective medium for ammonia-hydrogen-air flame stabilization which enables stable and efficient combustion of the mixtures…

Paper

Detailed Observation of Coal-Ammonia Co-Combustion Processes

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…

Paper

Combustion Emissions from NH3 Fuel Gas Turbine Power Generation Demonstrated

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…

Paper

Nitrogen-Based Fuels: Renewable Hydrogen Carriers

Renewable energy sources such as solar and wind suffer from an intermittent power output, making energy storage a key element in future energy infrastructure. Fuels offer both high energy densities and efficient transport compared to other energy storage alternatives. One energy storage solution is water electrolysis. However, the generated hydrogen is incompatible with the global fuel infrastructure, inhibiting its implementation as an energy vector. Storing hydrogen on carrier atoms provides a safe and convenient way to utilize and transport renewable energies. While carbon–based fuels are commonly suggested, using nitrogen as a hydrogen carrier can potentially offer a superior option. In…

Article

A Roadmap for Ammonia Fuel in Fujian Province

Researchers from Fujian Province presented their work at the 2016 NH3 Fuel Conference, and introduced the far-reaching plans of the Ammonia Fuel Synergy group at the College of Energy, Xiamen University, in China. Forest (Zhaolin) Wang's presentation, Ammonia as a Key to Meeting the Fuel Demand of China, contained valuable insight into the potential of ammonia fuel in China, and outlined the group's roadmaps for developing an ammonia-natural gas dual fueled car by 2018, and an ammonia-methanol dual fuel car by 2020.

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

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…

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

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…

Paper

Ammonia for Green Energy Storage and Beyond

Siemens is participating in an all electric ammonia synthesis and energy storage system demonstration programme at Rutherford Appleton Laboratory, near Oxford. The demonstrator, which will run until December 2017, is supported by Innovate UK. Collaborators include the University of Oxford, Cardiff University and the Science & Technology Facilities Council.