Electrical equipment filled with insulating SF

6

-N

2

gas has been widely used in China’s cold regions.Due to its relatively low liquefaction temperature

SF

6

-N

2

mixing gas in electrical equipment is difficult to be recycled effectively and rapidly with existing technology. To solve this problem

a two-stage membrane separation and recycling technology has been developed that can efficiently and rapidly retrieve SF

6

and N

2

gase

s. The concentration（V/V） of SF

6

in the recycled gas reaches 90%. Using the subsequent compression and refrigeration unit

gas recovery rate can reach 50 m3/h. This membrane separation technology can also enrich and retrieve the SF

6

gas from exhaust. The concentration of the retrieved SF

6

gas can be as high as 92%（V/V）

and the SF

6

concentration in the exhaustion is only 600 μL/L（V/V）

much lower than the national standard. Thus

the system can efficiently realize the quick recycling of SF

6

-N

2

insulating mixture and the exhaust emissions meets the national standard. It also solves problems encountered in operation.