六氟化硫与其主要分解产物的冷冻分离技术  

Frozen Separation Technology of Sulfur Hexafluoride and Its Main Decomposition Products

作　　者：谢辉[1] 马凤翔[1] 祁炯[1] 邵丽骅[1] XIE Hui MA Feng-xiang QI Jiong SHAO Li-hua(State Grid Anhui Electric Power Research Institute, Hefei 230022, Chin)

机构地区：[1]国网安徽省电力公司电力科学研究院,安徽合肥230022

出　　处：《安徽化工》2017年第2期53-57,60,共6页Anhui Chemical Industry

摘　　要：SF_6气体绝缘设备中分解产物检测能够为设备内部绝缘故障诊断和状态评估提供有效依据。然而通常在设备故障潜伏阶段,设备内SF_6气体分解产物含量极低,现有的测量方法难以进行有效检测。为提高分解产物的含量,根据SF_6与其主要分解产物液化温度的差异,提出一种低温冷冻分离的预处理方法,并实验研究了SO_2和CF_4的冷冻富集效果。研究结果表明:在一定气体压力下,温度降低至SF_6的相变温度(-63.8℃),大部分的SF_6迅速凝聚而被分离;低浓度的分解产物由于分压小,未达到相变条件,仍然保留在气相中,实现低浓度组分的富集。模型试验中,1.0MPa的试验气体经过冷冻分离,分解产物富集了约6倍。同时,在SF_6/H_2混合气体为背景气的冷冻分离试验中,处理前后分解产物的浓度显著提高,SF_6气体本底浓度显著减小,说明该方法对SF_6混合气体也同样适用。Operation experience shows that detecting the decomposition products of SF6 in the gas insulated equipment provides an effective basis for the fault diagnosis and state estimation of internal insulation of power equipment. However, in the equipment failure latent stage, the SF6 gas decomposition product content is very low, and the existing measurement methods are difficult to effectively detect. In order to improve the content of decomposition products, a pretreatment method of cryogenic freezing separation was proposed according to the difference of liquefaction temperature between SF6 and its main decomposition products. The freezing enrichment effect of SO2 and CF4 was studied experimentally. The results show Ihat under certain gas pressure, when the temperature decreases to the SF6 phase transition temperature （-63.8 ℃ ）, most of the SF6 is rapidly condensed and separated, and the low concentration decomposition products still remain in the gas phase and achieve the enrichment due to the small partial pressure does not reach the phase transition conditions. In the model test, 1.0 MPa test gas was frozen and the decomposition products were enriched about 6times. At the same time, in the fi＇eezing separation test with SF6/H2 mixed gas as the background gas, the concentration of decomposition products significantly increased, SF6 gas background concentration significantly reduced, indicating that the method for SF6 mixed gas is also applicable.

关 键 词：六氟化硫 分解产物 气体分析 富集分离 

分 类 号：TQ12[化学工程—无机化工] TM213[一般工业技术—材料科学与工程]