Development and Assessment of a Novel Integrated System Using an Ammonia Internal Combustion Engine and Fuel Cells for Cogeneration Purposes

Abstract

In this study, a novel ammonia-based integrated system, incorporating both ammonia-and hydrogen-fueled internal combustion engine and ammonia fuel cell system, is developed for cogeneration of power and cooling. The integrated system recovers the waste heat and uses it efficiently to achieve cooling and producing power. The performance of the present system is assessed and evaluated by using thermodynamic energy and exergy approaches. The energy efficiency of the overall cogeneration system is determined to be 59.9%, while the exergy efficiency is found to be 51.9%. Also, the energy efficiency of the ammonia fuel cell is evaluated as 44.4% and the exergy efficiency is found to be 41.7%. Further, the energy and exergy efficiencies of the internal combustion engine are determined to be 45.7 and 43.8%, respectively. Some parametric studies under actual operating conditions are conducted to assess the system performance at varying operating conditions and parameters.The developed system provides a new direction toward improving the performances of ammonia fuel cell systems through system integration, cogeneration, and waste heat recovery.

Flammability Limits of Ammonia in Air from 298 to 423 K at Elevated Pressures

“…A failure of the safety system could pose significant risks to the normal operation of large ships. For example, ammonia is also used as a reducing agent in coal-fired power plants and heavy-duty diesel vehicles to reduce nitrogen oxide emissions through selective catalytic reduction of nitrogen oxides. − The safe operation of downstream equipment is compromised by ammonia leakage, which has a negative impact on human health and environmental protection . Consequently, the combustion and explosion characteristics of ammonia must be understood to minimize potential hazards associated with the ammonia bunkering process and high-pressure fluid transfer.…”