Paper

Analysis of an Ammonia/Ammonium Nitrate Fuel’s Thermal Decomposition By Mass Spectrometry and Thermogravimetric Analysis

Research on renewable synthetic fuels has become a hot-topic in recent years. This is due to the long-term energy storage capabilities of chemical bonds and their potential compatibility with current energy infrastructure. Specifically, nitrogen-based fuels offer a carbon-free solution to wide scale implementation of renewable energies. Therefore, the inherent chemistry involved in the utilization of these fuels for stationary and mobile power generation is of prime interest. Unlike ammonium nitrate, ammonia suffers from unstable combustion characteristics. Therefore, adding ammonium nitrate to ammonia combustion may stabilize the process. However, while ammonia’s gas-phase reaction mechanism is well studied, ammonium nitrate’s is poorly…

Paper

Performance of Ammonia-Natural Gas Co-Fired Gas Turbine for Power Generation

Ammonia is paid special attention as renewable energy carrier [1-3], because it offers advantages in generation, transportation and utilization. Haber-Bosch method is already established as ammonia generation method; large amount of ammonia is already used as fertilizer and chemical raw material. Ammonia can be liquefied at room temperature. Its transport and storage system are already established. Ammonia is cheaper to transport than hydrogen. Ammonia can be used as carbon-free fuel in internal combustion engines as alternative to conventional hydrocarbon fuels. However, it has different combustion characteristics. For example, the nitrogen atom contained in the ammonia molecule, causes high NOx emission…

Paper

Auto-Ignition Kinetics of Ammonia at Intermediate Temperatures and High Pressures

The anxiety over global greenhouse gas emissions has intensified the demand for the development and use of CO2-neutral energy technologies. Ammonia is now attracting attention as a carbon-free energy carrier, because it has good energy density (22.5 MJ/kg) and can be easily liquefied (about 10 bar at 298 K). In addition, ammonia is produced according to the Haber-Bosch process, which makes it one of the most widely-produced inorganic chemical in the world. It could also be produced with renewable energy sources such as wind and solar energy using P2X technology. As a potential fuel for applications in gas turbines and…

Paper

Development of a Highly Efficient COx-Free Ammonia Dehydrogenation System for Fuel Cell Applications

The shortage of fossil fuels and emission of carbon dioxide to the environment have attracted an interest in discovering renewable energy as the next generation energy source. Owing to its intermittent and unpredictable nature, however, excess renewable energy needs to be stored and reused on demand. In the regard, hydrogen, which possesses a high gravimetric energy density and carbon free combustion process, has been extensively researched as a promising renewable energy carrier. However, the distribution and storage of hydrogen still raise important challenges due to the low volumetric energy density of hydrogen for its wide utilization. Currently, gaseous hydrogen transportation…

Paper

Ship Operation Using LPG and Ammonia As Fuel on MAN B&W Dual Fuel ME-LGIP Engines

LPG has been used as fuel in the car industry for many years and now, with Exmar and Statoil’s orders for ocean-going ships fitted with the dual fuel ME-LGIP engine, LPG will be used on marine engines as well. The new engine series is currently being developed to match all types of bigger merchant ships. This order was made in consequence of the new 2020 0.5% sulphur fuel cap, but this step forward has not stopped the discussion and interest in lowering CO2, NOx, SOx and particulate emissions even further. On the contrary, it has actually been further fuelled by…

Paper

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

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…

Paper

Methods for Low NOx Combustion in Ammonia / Natural Gas Dual Fuel Gas Turbine Combustor

Ammonia is a carbon-free fuel, so it has potential to reduce carbon dioxide emission from power plants when used as a fuel. However, combustion characteristics of ammonia are notably different from hydrocarbon fuels, especially regarding NOx emission [1]. The nitrogen atom of the ammonia molecule may cause high NOx emission. Therefore, special techniques to reduce NOx emission are essential for gas turbine combustors which burn ammonia and natural gas. The results of our previous study [2] showed the characteristics of NOx emission in single-stage combustion. In this study, the concept for low-emission combustion in two-stage combustion has been examined numerically…

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

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

Effect of Water on the Auto-Ignition of a Non-Carbon Nitrogen-Based Monofuel

The fluctuating nature of renewable energy sources is becoming a limiting factor in their widespread utilization. Energy storage solutions must be developed to overcome this issue. Chemical fuels are considered to be a promising solution to this problem. We are studying the implementation of nitrogen-based fuels for this purpose. An aqueous solution of ammonium nitrate and ammonium hydroxide (AAN) is suggested as a carbon-free nitrogen-based synthetic monofuel. This solution may serve as a renewable nitrogen-based synthetic hydrogen carrier since it is safe to store, transport and utilize. Since ammonium hydroxide (AH) and ammonium nitrate (AN) act as reducer and net…