大规模可再生能源电解水制氢合成氨关键技术与应用研究进展

新能源的快速发展为电力和化工行业带来了机遇和挑战，一方面，由于可再生能源电力消纳问题导致大量的弃水、弃光等能源浪费，另一方面，以绿氢为原料替代碳基化石能源合成氨，可以极大地减少化工行业的碳排放。因此，利用水力、光伏等可再生能源电解水制氢，为合成氨提供绿色原料，可显著提升可再生能源消纳能力，降低能耗与碳排放，服务国家“碳达峰、碳中和”目标。然而，可再生能源电力电量的波动性难以适配传统合成氨生产过程的平稳性要求，大规模可再生能源电解水制氢合成氨的设计与运行依然存在诸多挑战，亟需开展系统性研究突破适应可再生能源波动特性的大规模电解水制氢合成氨系统的集成与调控关键技术。对此，本文首先对可再生能源电解水制氢合成氨的工艺组成及过程进行介绍，包括电解水制氢工段、压缩缓冲工段、化工合成氨工段，进而提出该系统建设的关键技术体系，包括可再生能源波动条件下的合成氨工艺流程优化和柔性调控技术、考虑“电-热-质”耦合的大规模电解水制氢系统的模块化集成和集群动态控制技术、计及可再生能源波动性与化工多稳态特性的“源-网-氢-氨”的全系统协同控制技术、计及电、氢、氨等要素的全方位安全防护与市场运营机制。针对适用于柔性生产的合成氨工艺优化及多工段协同调控技术，在考虑氢储供量与催化剂性能下，综合合成塔、压缩机、气体分离、换热网络等子系统开发了合成氨高保真代理模型；研究了可再生能源供给和市场需求波动下，充分考虑操作安全性和过程经济性的电解水制氢合成氨各子系统的适配方案与协同控制技术。针对大规模电制水制氢系统模块化集成和集群动态控制技术，基于奇异摄动和代理模型技术研究了集群系统多时间尺度时域仿真方法，建立了电解集群系统多物理耦合状态空间模型；综合考虑了模块启停组合调度、模块间功率分配调度及模块自身灵活调节，计及安全运行区间及电热气接口特性约束，以提高氢产量、提升能量利用效率、改善水光电源消纳和跟踪电网调峰调频指令为目标，构建了集群系统多目标分层调度与控制模型。针对氢能参与电网的全系统协同控制技术，研究了水光互补发电、电制氢、储氢、合成氨、储氨多工段间稳态运行特性的多工段间灵活运行方法，以及电制氢合成氨系统柔性动态协同控制方法；综合采用了静态等值和参数聚合等方法降维和等值电制氢合成氨系统仿真模型，研究了源网氢氨协同提升系统安全稳定性的优化控制方法和技术指标；结合电网调频和调峰特性，研究了电制氢合成氨系统参与电力辅助服务的策略。建设大规模可再生能源电解水制氢合成氨系统，提高可再生能源本地消纳率和并网调度友好性，降低化工碳排放，具有显著社会效益和战略意义。

Research Review of the Key Technology and Application of Large-scale Water Electrolysis Powered by Renewable Energy to Hydrogen and Ammonia Production

The rapid development of new energy has brought opportunities and challenges to the electric power and chemical industry. On the one hand, the consumption of renewable energy leads to a large amount of waste of energy such as water and light. On the other hand, replacing carbon-based fossil energy ammonia with green hydrogen as raw material can greatly reduce the carbon emissions of the chemical industry. Therefore, the use of hydropower, photovoltaics and other renewable energy sources to electrolyze water to produce hydrogen can provide green raw materials for ammonia synthesis, which can significantly improve the capacity of renewable energy consumption, reduce energy consumption and carbon emissions, and serve the national goal of "carbon peaking and carbon neutrality". However, the fluctuation of renewable energy power is difficult to meet the stability requirements of the traditional synthetic ammonia production process, and there are still many challenges in the design and operation of large-scale renewable energy electrolysis of water to produce hydrogen and synthetic ammonia. There is an urgent need to carry out systematic research and breakthroughs in key technologies for the integration and regulation of large-scale electrolysis of water for hydrogen production to ammonia synthesis systems that adapt to the fluctuating characteristics of renewable energy. In this regard, this paper firstly introduces the composition and process of the renewable energy electrolysis water process, including the electrolysis water hydrogen production section, the compression buffer section, and the chemical ammonia synthesis section. Furthermore, the key technical system for the construction of the system is proposed, including the optimization of the synthetic ammonia process flow and the flexible control technology under the fluctuating conditions of renewable energy, the modular integration and Cluster dynamic control technology, "source-grid-hydrogen-ammonia" system-wide coordinated control technology for the volatility of renewable energy and multi-stable characteristics of chemical industry, comprehensive security protection and market operation for electricity, hydrogen, ammonia and other elements mechanism. Aiming at the optimization of synthetic ammonia process and multi-stage cooperative regulation technology suitable for flexible production, a high-fidelity proxy model for synthetic ammonia was developed by integrating the subsystems of synthetic tower, compressor, gas separation and heat transfer network, considering the hydrogen storage and supply quantity and the performance of catalyst. The adaptation scheme and collaborative control technology of each subsystem of water electrolysis for hydrogen production and ammonia synthesis under the fluctuation of renewable energy supply and market demand are studied. Aiming at the modular integration and cluster dynamic control technology of large-scale electric water and hydrogen production system, the multi-time-scale time-domain simulation method of cluster system was studied based on singular perturbation and agent model technology, and the multi-physical coupling state space model of electrolytic cluster system was established. Considering the module start-stop combination scheduling, scheduling and power allocation between the module itself flexible adjustment, and safe operation of the interval constraint and electric heat interface features, in order to improve the hydrogen yield, improve energy use efficiency, improve the above power given and tracking grid load frequency control instruction as the goal, to build the multi-objective hierarchical cluster system scheduling and control model. Aiming at the whole system cooperative control technology of hydrogen energy participating in power grid, the flexible operation method of multiple sections with steady-state operation characteristics of water-light complementary power generation, electric hydrogen production, hydrogen storage, ammonia synthesis and ammonia storage is studied, and the flexible dynamic cooperative control method of electric hydrogen production and ammonia synthesis system is also studied. The simulation model of electric hydrogen production and ammonia synthesis system with static equivalent and parameter aggregation methods was integrated. The optimal control method and technical index of the system with hydrogen ammonia in the source network were studied. Combined with the characteristics of frequency modulation and peak regulation, the strategy of electric hydrogen production and ammonia synthesis system participating in power auxiliary service is studied. It has significant social benefits and strategic significance to improve the local consumption rate of renewable energy and the friendliness of grid-connected scheduling by building a large-scale water electrolysis system for hydrogen production and ammonia synthesis with renewable energy, and reduce chemical carbon emissions.