Abstract: The integration and optimization of hydrogen distribution network is of great significance for rational allocation of hydrogen and reduction of production costs for refineries. For the hydrogen distribution network with intermediate levels，a stepwise optimization model is proposed，in which the states of intermediate levels are determined first，and then a centralized purifier is installed. The installation strategy of the centralized purifier in the hydrogen distribution network with intermediate levels is analyzed. A case study is employed to illustrate the effectiveness of the proposed method. The results show that the proposed method can not only make the network structure scalable，but also can reduce the consumption of hydrogen utilities and save the hydrogen cost in refineries.

Key words: hydrogen, hydrogen network, intermediate level, purification, a centralized purifier, optimization

摘要： 氢气系统的集成与优化对于炼厂合理配置氢气资源和降低生产成本具有重要意义。针对具有中间等级氢气分配网络系统，本文提出了先确定中间等级状态再设置集中式提纯器的氢气网络分步优化模型，分析了在具有中间等级氢气网络中优化设置集中式提纯器的策略，并通过实例阐明了本文所提出方法的有效性。研究表明：对于具有中间等级的氢气网络系统，集中式提纯器应设置在氢源与中间等级之间，本文所提出的优化方法不仅使氢气网络结构具有可扩充性，而且可降低氢气公用工程的用量，减少炼厂的用氢费用。

关键词: 氢, 氢气网络, 中间等级, 纯化, 集中式提纯器, 优化