Pipeline sharing: Optimal design of downstream green ammonia supply systems integrating with multi-product pipelines

Green ammonia is a promising energy storage form with extremely high efficiency of hydrogen storage. Although the construction of green ammonia production facilities is rapidly progressing, there is still a lack of comprehensive consideration of the optimal design for supply systems. This paper prospectively explores a framework for the ammonia supply system under four scenarios considering multimodal transportation. Different mathematical models are developed, which incorporate special constraints such as pipe diameter, broken loops, etc., aiming at minimizing costs of transportation, construction and carbon treatment. In this framework, the economic, energy and environmental performance is evaluated to optimize the design of the supply system. The case study in China shows that different transportation modes can reduce economic costs by 60.93∼77.45 %, energy consumption by 18.4 ∼67.7 ktce, and carbon emissions by 23.3∼60.7 kt per year. A further novel finding is that the simultaneous usage of new liquid ammonia pipelines and multi-product pipelines for supply systems proves to be the most effective transportation mode. Sensitivity analyses are also conducted on regional production capacity expansion, liquid ammonia pipeline planning, and multi-product pipeline utilization. The results confirm that the scheme is stable under certain conditions. Finally, some recommendations are provided for the development of green ammonia industry.