The use of water curtains has been shown to be promising in reducing the toxic effect distances of ammonia releases for both unconfined and confined spaces (/1/, /2/).
Two concurring effects are believed to contribute to remove ammonia from the plume: the increased turbulence generated by the curtains and the high solubility of ammonia in water.
Yet, currently, there are no engineering guidelines for the design of water curtain systems aimed at mitigating toxic releases.
Numerical models, on the other hand, (including 3D CFD) have been proposed to simulate the effectiveness of this measure (/3/).
This paper includes:
• A critical review of the available experimental data on ammonia releases and mitigation by water curtains
• The description of a 3D CFD model capable to capture the main features of the interaction of the toxic plume with the water curtains.
• The use the model to estimate the mitigating effect for some representative ammonia releases during bunkering operations.
• The model will simulate a set of release scenarios selecting a combination of values for the most important parameters: ammonia release rate, wind speed, wind direction, layout of the nozzles and water:ammonia ratio.
• Discussion on the effectiveness of the measures and any observed trend in the data.

References
/1/ Dandrieux & al.- Effectiveness of water curtains to protect firemen in case of an accidental release of ammonia: comparison of the effectiveness for two different release rates of ammonia - Journal of Loss Prevention in the Process Industries 14 (2001) 349–355
/2/ Hua &al. - Experimental Research on Water Curtain Scavenging Ammonia Dispersion in Confined Spaces - Procedia Engineering 211 (2018) 256–261
/3/ Cheng&al - Numerical simulation of water curtain application for ammonia release dispersion - Journal of Loss Prevention in the Process Industries 30 (2014) 105-112