““The application of waste heat recovery from the calcination process in the caustic soda industry to efficient and energy-saving crystallization cooling technologies” passed the appraisal of scientific and technological achievements by the China Petroleum and Chemical Industry Federation​

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““The application of waste heat recovery from calcination in the caustic soda industry for efficient energy-saving crystallization cooling technology” passed the evaluation for scientific and technological achievements by the China Petroleum and Chemical Industry Federation. Author/Source: Modern Coal Chemical Engineering. Date: May 15, 2022. Clicks: 24. On May 10, 2022, the China Petroleum and Chemical Industry Federation organized a video evaluation meeting to assess the scientific and technological achievements related to this technology. This technology was jointly developed by Lianyungang Fuyuandebon Technology Development Co., Ltd. and Anhui Debon Chemical Co., Ltd. The appraisal meeting was chaired by Wang Xiujiang, deputy director of the Science, Technology and Equipment Department of the China Petroleum and Chemical Industry Federation. The expert panel of the appraisal committee consists of 9 experts, including Dou Jinliang, Secretary-General of the China Soda Ash Industry Association; Chen Jianru, Chief Process Engineer at Jiangsu Huachang Chemical Co., Ltd.; and Dong Wenlin, Deputy General Manager of Henan Jinshan Chemical Group. Wang Xiujiang, deputy director of the Department of Science, Technology and Equipment at the China Petroleum and Chemical Industry Federation, and Wang Qian, the person in charge, attended the meeting as organizers. Zhuo Shibin, General Manager of Lianyungang Fuyuandebang Technology Development Co., Ltd., the company responsible for completing this project, along with Deputy General Manager Song Shinen, Chief Engineer Zhao Chuan, Zhang Jingzhu, General Manager of Anhui Debang Chemical Co., Ltd., and Deputy General Manager Huo Jiefang, attended the meeting. Special guests included Li Ruifeng, a professor-level engineer from China Chengda Engineering Co., Ltd., as well as Duan Yonghong and Xue Xing, senior engineers from Ebara Thermal Systems (China) Co., Ltd. Through numerous studies and experiments on the application of waste heat recovery from the calcination process in caustic soda production to efficient energy-saving technologies and devices for crystal cooling, the technology development team invented and designed a specialized lithium bromide-based refrigeration system as an alternative to the ammonia compressor-based liquid ammonia refrigeration process. This system helps to reduce the crystallization temperature of ammonium chloride in the caustic soda crystallization stage, thereby replacing the traditional liquid ammonia compressor-based refrigeration process as well as related equipment such as ammonia compressors, evaporation coolers, liquid ammonia exchangers, and ammonia separators. It also helps to address the safety and environmental issues associated with the liquid ammonia refrigeration process. By recycling the waste heat from the calcination system and using lithium bromide chillers instead of ammonia compressors for cooling in order to lower the crystallization temperature, the electrical consumption of the system is significantly reduced. Rational use of energy allows the electrical consumption per unit of product in traditional soda ash production plants using the alkaline synthesis method to be reduced by approximately 48 kW·h. The appraisal committee listened to the work reports, research reports, application reports, novelty search reports and other presentations prepared by Chief Engineer Zhao Chuan, and reviewed the relevant technical documents. After questions, defenses, and thorough discussions, the experts unanimously agreed that: (1) This technology utilizes the waste heat from the calcination system as a heat source, and employs lithium bromide units to produce chilled water for cooling, instead of using liquid ammonia from ammonia compressors ； It eliminates the major hazard sources in the liquid ammonia refrigeration process, reduces the risk level of the facility, and achieves significant energy savings and carbon reduction. By using a pre-cooling crystallization device, the temperature of the cold ammonia I mother liquor in the double-alkali process can be reduced below the critical point for crystal formation, thereby reducing the load associated with cold crystallization and addressing the issue of blockages due to intense heat exchange in the mother liquor ； At the same time, increasing the temperature of Mother II meets the temperature requirements of the carbonization system and reduces the system’s energy consumption. (2) This technology has been successfully applied in the 600,000-ton-per-year soda ash production project of Anhui Debang Chemical Co., Ltd. The operation results show that the system runs safely and stably, and compared with the original system of this facility, the electricity consumption per unit of product has decreased by 48 kW·h. The waste heat from the calcination furnace is recovered and utilized, resulting in significant savings in energy and carbon emissions as well as cleaner production processes. This approach yields good economic, environmental, and social benefits, and it holds broad application prospects in soda ash manufacturers that use the alkali synthesis method. (3) This technology is highly innovative, possesses independent intellectual property rights, and has reached an international advanced level; it is recommended for widespread adoption in the soda ash industry. This technology was developed by the originating entity; it holds 2 invention patents and 5 utility model patents. On November 26, 2019, it was included by the **Ministry of Industry and Information Technology in the \"Recommended Catalogue of Industrial Energy-Saving Technologies and Equipment (2019)\", under the category of industrial energy-saving technologies (IV): Renewable energy and waste energy utilization technologies. As a technology that promotes green and clean production, it is recommended that its adoption be accelerated.