(542f) Ignition of an Aqueous Ammonia/Ammonium Nitrate Fuel

Bar Mosevitzky, Gennady
E. Shter, Gideon S. Grader^*

*Corresponding author: grader@technion.ac.il

Wolfson Department of Chemical Engineering, Nancy and Stephen Grand
Technion Energy Program, Technion-Israel Institute of Technology, Haifa
3200003, Israel

To achieve a truly renewable energy market, the intermittent power
generation of sources such as solar and wind must be overcome. Renewable ammonia
can be synthesized using these sources to be used as a long-term energy storage
medium. For this reason, the use of ammonia as a synthetic fuel has garnered
significant attention in recent years. Aqueous AAN (ammonia/ammonium nitrate) is
a carbon-free ammonia based monofuel suitable for energy storage applications. This
fuel is safe to store and transport, and its combustion products consist mainly
of water and nitrogen. Effective use of this fuel requires an in-depth understanding
of the reaction pathways dominating its ignition.

In this work, the accumulated results from experiments conducted to
test the effects of water content (Fig. 1a), equivalence ratio (Fig. 1b) and
diluent pressure (Fig. 1c) on AAN ignition will be reviewed. The use of simulations
to reproduce these results will be evaluated, and the data generated by
rate-of-production and sensitivity analyses will be reviewed. Finally, the
reaction pathways involved in AAN ignition and their relation to its water content,
equivalence ratio and diluent pressure will be presented, and the implications
of the rate-determining steps for AAN ignition will be discussed.

Figure 1. The effects of: (a) water content, (b) equivalence ratio
and (c) diluent pressure on the Autoignition Temperature (AIT) of AAN.