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Ningxia Coal plans to connect the oxygen pipelines of Series 1 and Series 2 of the air separation units. Author/Source: Gasification World. Date: 2021-08-17. Clicks: 15. Shenhua’s coal-to-oil air separation plant has a total of 12 air separation units with a capacity of 100,000 Nm3/h each; these units are divided into 2 series to supply oxygen to 28 gasification furnaces. The oxygen pipelines of the two series are arranged independently, with 14 gasifiers corresponding to each series; they cannot supply oxygen to one another, which restricts the overall coordination of production operations. Moreover, when a single-series air separation unit operates at low load for an extended period, the production costs are high and its operational economics are poor. After multiple discussions and model analyses with Hualu Design Institute, Ningbo Engineering Company, and Hangzhou Hangyang Company, as well as a HAZOP analysis conducted with Beijing United Pukeng Company, this air separation plant is considering connecting the oxygen pipelines of Series 1 and Series 2, in order to meet the requirements of the gasification furnaces in subsequent systems while ensuring safety. To thoroughly assess the operational risks associated with the connection of oxygen pipelines for units such as air separation and gasification, and to ensure that the basic design complies with regulations and standards, thereby guaranteeing safety and reliability once the project is put into operation. On August 12, Jiang Yong, the director of Shenhua Ningmei Air Separation Plant, presided over a safety review meeting for the basic design of the oxygen pipeline connection technical renovation project. Seven experts from the air separation industry and design institutes, including Yang Mingli, Wang Zhongjian, Zhang Xu, Lei Li, etc. (who participated via video link), as well as staff from relevant departments such as the Coal-to-Oil Chemicals Department, the Safety and Environmental Protection Supervision Department, the air separation workshops of the Olefins Division 1, the air separation workshops of the Methanol Division, the Coal-to-Oil Production Management Department, the Mechanical and Power Department, the Air Separation Plant, and the Instrument Control Center, attended the meeting. The meeting agreed that the oxygen pipeline connection design is feasible, safe, and reliable, and recommended proceeding with this project. The expected outcome of connecting the oxygen pipeline is more flexible production coordination. After the oxygen pipeline was connected, the air separation unit could be maintained in a configuration of 10 units in operation with 1 in standby, instead of 5 in operation with 1 in standby. The 12 air separation units could now supply gas to the 28 gasification furnaces freely, without any constraints. The energy consumption of the device is effectively reduced. The overall load of the air separation unit is more balanced, and liquid oxygen sales are not affected by the liquid level in the oxygen storage tank. Emergency response time has been significantly improved. The oxygen backup system enables shutdown, reduces power consumption, and increases the oxygen backup emergency time from 16 hours to 32 hours. Next, the air separation plant will accelerate the approval and implementation of the technical upgrades for the oxygen pipeline connection project, striving to achieve this connection as soon as possible.