368 / 2019-03-12 15:56:23

The Detection of Hydrolyzable Fluoride in SF6 Equipment by Ion Chromatography and Application in Fault Determination

Ion Chromatography,Hydrolyzable Fluoride,Fault Determination

SF6 in the faulty gas insulation equipment can be resolved into low-fluoride sulfide under the effect of high energy. Some of them such as SF2、S2F2 、SF4、SOF2、SOF4 are easy to take hydrolysis and alkaline reactions, and some such as SO2F2, are able to occur partially alkaline reactions, and some are almost impossible to decompose such as S2F10、S2F10O and so on. The total amount of low-fluoride sulfide which can undergo hydrolysis and alkaline reactions in SF6 could be determined by hydrolysis fluoride. Therefore, if the content of hydrolyzable fluoride is found to be significantly higher than its initial value, some internal faults may exist in the equipment. In addition, hydrolyzable fluoride in SF6 will lead to the corrosion and accelerate deterioration of equipment and solid insulation materials. The amount of hydrolyzable fluoride represents the degree of toxicity, which is one of the important indicators of the quality control of SF6. In this paper, the amount of the hydrolyzable fluoride in SF6 is determined by ion chromatography. The variation tendencies of hydrolyzable fluoride are investigated under discharge and overheating conditions and the content of hydrolyzable fluoride in SF6 in normal and failure conditions is compared. In this paper, the traditional method is improved by simplifying the absorption method of the lye absorption step and adopting mechanical oscillation absorption, which make the absorption effect is controllable, the automatic drawing by the ion chromatography workstation in the standard working curve drawing step, which makes the operation easier. In the end, a reference value related to hydrolyzable fluoride for fault diagnosis is proposed, which has a certain reference significance for judging the fault condition in SF6 equipment.