Research on Environmental Protection Treatment for Ex-Service SF6 Adsorbent

• Published in: IEEE access Vol. 8; pp. 93840 - 93849
• Main Authors: Wei, Gang, Bai, Yichun, Hu, Min, Cao, Zhengqin, Fu, Wei
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Absorption; Adsorbates; Adsorbents; Adsorption; Economic conditions; Environmental protection; Fourier transform infrared spectroscopy; Fourier transforms; harmless treatment; Heating systems; Hydrogen sulfide; Infrared analysis; Instruments; Molecular sieves; Recycling; SF₆ adsorbent; Slaked lime; Sulfur hexafluoride; Temperature measurement; Thermogravimetric analysis
• ISSN: 2169-3536
• DOI: 10.1109/ACCESS.2020.2994818

SF 6 adsorbents absorb many toxic SF 6 decomposition products, such as SOF 2 , SO 2 F 2 , and H 2 S. Ex-service SF 6 adsorbents that did not undergo environmentally friendly processing will seriously harm the environment. In this work, thermogravimetric analysis and Fourier transform infrared spectroscopy were used to investigate the adsorbates of ex-service SF 6 adsorbents. Adsorbent recycling based on the thermal method was also studied. The vacuum thermal method increased the recycling efficiency of ex-service SF 6 adsorbents to 85%-90%. In addition, the adsorbents recovered through thermal method could be reused in SF 6 -gas-insulated equipment. Considering their influence on equipment operation and maintenance, a harmless treatment technology for ex-service SF 6 adsorbents with Ca(OH) 2 was proposed. The adsorption and desorption behaviors of SF 6 adsorbents were predicted via destiny functional theory. The best treatment effect could be obtained when the Ca(OH) 2 amount was equal to 20% of the treatment weight of the adsorbents, and the treatment temperature was maintained at 90 °C. The economic feasibility of the harmless treatment for ex-service SF 6 adsorbents with Ca(OH) 2 was higher than that of the thermal method.