Complete recovery of released ammonia from fuel supply system of ammonia fueled ship using novel adsorption unit

As ammonia emerges as a promising zero carbon marine fuel, addressing the challenges associated with its toxicity and handling has become critical for safe onboard operation. Among various operational requirements, nitrogen purging is required to safely remove residual ammonia from the fuel supply system during emergency operation or maintenance procedures. However, the released ammonia poses environmental and safety risks due to its high toxicity, necessitating the development of an effective recovery system. This study presents a comprehensive dynamic simulation of the nitrogen purging process in an ammonia fuel supply system using Aspen HYSYS, where the flow characteristics of the discharged ammonia were analyzed under varying purging conditions. To evaluate recovery strategies, an adsorption unit adopting newly synthesized zeolite-13X impregnated with 0.5 wt% MgCl 2 was designed. An adsorption model incorporating the adsorbent was first validated using experimental isotherm and breakthrough data. Based on the validated model, a temperature swing adsorption (TSA) unit was developed using Aspen Adsorption under time-dependent inlet conditions derived from the purging simulation. The performance of the TSA unit was compared with other mitigation strategies including water scrubbers and ammonia boilers in terms of equipment size and energy consumption. The obtained results show that the TSA unit provides a compact alternative capable of fully recovering ammonia for potential reuse with less energy consumption than other mitigation strategies. These findings highlight the feasibility of the adsorption unit as a sustainable solution for ammonia release mitigation in ammonia fueled ships.