Cost of ammonia reduced by over 230 yuan per ton; major breakthrough in ammonia synthesis technology in China

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Cost of ammonia production reduced by over 230 yuan per ton; major breakthrough in ammonia synthesis technology in China. Author/Source: Coal Chemistry News. Date: April 27, 2020. Clicks: 52. From April 20 to 23, 2020, the DN1800 industrial “iron-ruthenium relay catalytic” ammonia synthesis system, jointly designed, developed, and built by Sanyu Environmental Protection, Fuzhou University, the Research Institute of Petroleum and Petrochemicals of China National Petroleum Corporation, Jiangsu Heyou Chemical Industry, and Nanjing Jutuo, successfully passed a 72-hour on-site evaluation of its technical and economic performance organized by the China Petroleum and Chemical Industry Federation. The results of the 72-hour on-site evaluation by the expert team showed that the newly built industrial \"iron-ruthenium relay\" ammonia synthesis system achieved an ammonia yield of 14.5 vol% under conditions of an operating pressure of 12.7 MPa, a total column space velocity of 7463 h-1, and an inert gas content of 14.9 vol%; the pressure drop across the entire system was 0.4 MPa ； The standard coal consumption per ton of ammonia is 1084 kgce, the electricity consumption per ton of ammonia is 1204 kW·h, and the steam generated as a by-product per ton of ammonia is 992 kg. The ammonia synthesis pressure and the hotspot temperature in the catalyst bed are significantly reduced, resulting in a substantial improvement in intrinsic safety ； Under conditions of low temperature, low pressure, a low hydrogen-to-nitrogen ratio, and a high content of inert gases, a high ammonia yield was achieved, which is more than 35% higher than the ammonia yield obtained using traditional iron-based ammonia synthesis techniques under high temperature and pressure conditions. The panel of experts unanimously agreed that the world’s first industrial ammonia synthesis plant using coal as a raw material and employing \"iron-ruthenium relay catalysis,\" along with the catalyst loading technology based on \"two types of iron and two types of ruthenium,\" ensures safe, stable, and efficient operation of the ammonia synthesis reactor ； The temperatures of the gases at the inlet and outlet of the ruthenium catalyst bed and the synthesis tower, as well as the ammonia concentration and the net ammonia value, remain stable ； Ruthenium-based ammonia synthesis catalysts feature high activity and stable performance, and the complete set of process technologies and equipment fully meet the requirements for continuous, safe, and efficient industrial ammonia production. “Compared with existing traditional iron-based ammonia synthesis technologies at home and abroad, the \"iron-ruthenium relay catalysis\" ammonia synthesis technology results in a significantly lower comprehensive energy consumption per ton of ammonia produced, offering notable economic and social benefits, which facilitates the upgrading of the ammonia synthesis industry. Due to the impact of the pandemic, this assessment and calibration were carried out through a combination of video conferences and on-site inspections. The expert group consists of three experts: Yang Chao, a researcher at the Institute of Process Engineering, Chinese Academy of Sciences; Cao ZhanGao, a senior engineer at the China Nitrogen Fertilizer Industry Association; and Wu Jianjun, a professor at China University of Mining and Technology. Hu Qianlin, Deputy Secretary-General of the China Petroleum and Chemical Industry Federation; Jiang Yanru, Section Chief; Duan Yonghong, Deputy Section Chief; Hu Juan, Business Supervisor; Bu Qifang, Chairman of Youyou Group; Wang Jie, Chairman of Jiangsu Heyou Chemical, and Cheng Zejin, General Manager of the same company; Li Lin, General Manager of Sanju Environmental Protection, and Wu Yongtao, Assistant to the President; as well as Jiang Lilong, Director of the Fertilizer Catalyst Engineering Research Center at Fuzhou University – among other experts – participated in the assessment and calibration process. Jiangsu Heyou Chemical uses low-quality anthracite as raw material and still employs the traditional batch fixed-bed atmospheric gas generation technology. A high-performance sulfur-resistant shift catalyst developed jointly by Fuzhou University and Sanju Environmental Protection is used for the conversion of carbon monoxide, followed by decarburization via PSA and purification through the dimethyl process. The purified fresh gas contains 0.8–1.0% inert gases, which are mixed with recycled gas before being fed into the newly built DN1800 iron-ruthenium ammonia synthesis system for ammonia production. The core of the upgrade to Heyou Chemical’s ammonia synthesis technology lies in the adoption of a new ammonia synthesis process based on ruthenium-based catalysts, thereby addressing the issues associated with the original high-pressure ammonia synthesis system, such as low reaction efficiency, high energy consumption in ammonia production, and safety problems. The new DN1800 iron-ruthenium catalytic ammonia synthesis system was initiated for development in May 2017 by Sanju Environmental Protection. Through close integration of industry, academia, and research, a DN1800 \"iron-ruthenium catalytic\" ammonia synthesis system was built on the basis of the original DN1400 iron-based ammonia synthesis system at Jiangsu Heyou. The new system was successfully commissioned in one go on July 24, 2019, and has since operated stably for a total of approximately 6,000 hours. Through this renovation, it is conservatively estimated that the newly built industrial \"iron-ruthenium relay\" ammonia synthesis system reduces the overall energy consumption per ton of ammonia by over 230 yuan compared to the traditional iron-based ammonia synthesis system used by Heyou Chemical, while also significantly improving its intrinsic safety. Currently, the \"Low-pressure Isobaric Ammonia Synthesis Reactor Complete System\" has been included in the Ministry of Industry and Information Technology’s \"Guidance Catalogue for the Promotion and Application of First-of-Kind Major Technical Equipment (2019 Edition)\". This catalog was released on December 30, 2019, and came into effect on January 1, 2020, with the aim of accelerating the promotion and application of China’s first-of-a-kind technologies and equipment, as well as continuously improving the level of innovation in major technical devices.