Low-carbon and economic operation of integrated energy systems in ammonia-production chemical parks

The ammonia production chemical industry, recognized as a major contributor to energy consumption and carbon emissions, urgently necessitates effective strategies to reduce carbon emissions. Due to the immaturity of green ammonia technology and its stringent geographical requirements, the green retrofitting of in-service ammonia production chemical parks has emerged as the important approaches to respond to the dual-carbon targets. Based on traditional production parks, this paper proposes a low-carbon retrofitting scheme featuring the collaboration of multiple hydrogen sources within the park for the first time. It constructs a framework for the park integrated energy system (PIES) and conducts a detailed analysis of the energy coupling relationships in the production process. Renewable energy is installed on the rooftops of buildings and the spaces around the park. The carbon capture and storage (CCS) is introduced, and the carbon sequestration through the photosynthesis of green plants is taken into account. Moreover, a low-carbon economic operation strategy through the collaboration of multiple hydrogen sources is proposed, which reduces carbon emissions. Finally, three performance indicators are introduced to comprehensively evaluate the carbon reduction efficacy of the proposed approach, and sensitivity analyses are conducted across various scenarios characterized by parameter variations. The results indicate that the retrofitting scheme and operation strategy lead to a 36.53 % reduction in the daily total consumption of fossil fuels, a 25.13 % decrease in daily operating costs, and a 46.10 % reduction in carbon emissions, making the production process more low-carbon and economically efficient.