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Ammonia

About: Ammonia is a research topic. Over the lifetime, 16217 publications have been published within this topic receiving 271940 citations. The topic is also known as: NH3 & azane.


Papers
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Journal ArticleDOI
01 Feb 2011-Fuel
TL;DR: In this paper, a fuel system for ammonia-fired internal combustion engines using metal ammine complexes as ammonia storage is analyzed, and it is shown that a fuel mixture with 10 vol.% hydrogen performs best with respect to efficiency and power.

195 citations

Journal ArticleDOI
TL;DR: In this paper, the authors used atmospheric transport models and critical loads to control nitrogen emissions from various sources, such as agriculture, road traffic, stationary sources and other mobile sources (including vehicular emissions from agriculture).
Abstract: The atmosphere in Europe is polluted by easily available nitrogen (ammonium and nitrate) mainly from livestock (NH3), traffic (NOx) and stationary combustion sources (NOx). The nitrogen emission from various European sources decreases in the order: agriculture, road traffic, stationary sources and other mobile sources (including vehicular emissions from agriculture), with annual emissions of approximately 4.9, 2.7, 2.7 and 0.8 Mt N respectively. The emissions have increased dramatically during the latest decades. In the atmosphere the pollutants are oxidised to more water soluble compounds that are washed out by clouds and eventually brought back to the earth's surface again. Since ammonia is emitted in a highly water soluble form it will also to a substantial degree be dry deposited near the source. Ammonia is, however, the dominant basic compound in the atmosphere and will form salts with acidic gases. These salt particles can be transported long distances especially in the absence of clouds. The deposition close to the source is substantial, but hard to estimate due to interaction with other pollutants. Far from the source the deposition of ammonium is on an annual average halved approximately every 400 km. This short transport distance and the substantial deposition near the source makes it possible for countries to control their ammonium deposition by decreasing their emissions, provided that there is no country with much higher emission in the direction of the prevailing wind trajectory. When the easily available nitrogen is deposited on natural ecosystems (lakes, forests), negative effect can occur. The effect is determined by the magnitude of the deposition and the type of ecosystems (its critical load for nitrogen). In order to reduce the negative effects by controlling the emissions in a cost-efficient way it is necessary to use atmospheric transport models and critical loads.

194 citations

Journal ArticleDOI
TL;DR: A small single dose of ammonium citrate of high N15 concentration is administered to both rats and human subjects maintained at various levels of nitrogen output in order to study the effect of dietary conditions on the utilization of ammonia.

193 citations

Journal ArticleDOI
TL;DR: Methane fermentation that was carried out along with ammonia striping to avoid ammonia accumulation that significantly inhibited methane production was demonstrated and methane production from chicken manure was successfully produced.

193 citations

Journal ArticleDOI
TL;DR: In this paper, an energy analysis of the thermal decomposition of solid urea and urea solutions is presented, and the results are discussed in view of urea selective catalytic reduction (SCR) for automotive DeNOx systems.
Abstract: An energetic analysis of the thermal decomposition of solid urea and urea solutions is presented, and the results are discussed in view of urea selective catalytic reduction (SCR) for automotive DeNOx systems. Various types of decomposition reactors are possible which differ in their effectiveness to produce ammonia from urea. For reasons of simplicity, the decomposition is usually performed by atomizing urea solutions directly into the hot exhaust. However, this technique suffers from short residence times, leading to incomplete decomposition into ammonia and isocyanic acid and causing a significant performance loss of the SCR catalyst. The thermal decomposition out of the main exhaust stream allows much increased residence times for the process of urea decomposition. A reactor utilizing a partial stream of the exhaust seems particularly promising, especially if such a reactor includes a hydrolyzing catalyst, leading to ammonia practically free from isocyanic acid.

193 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20231,701
20223,035
2021425
2020443
2019496
2018511