| 主权项 |
1. A system for separating and recycling a perfluoro compound, which is configured to treat a dust-containing gas generated from an exhaust gas generating facility that uses or produces a perfluoro compound discharged in a dry etching process and a CVD chamber cleaning process, the system comprises:
a buffer tank 1 including an extension tube 11 formed at one side thereof so as to allow an exhaust gas generated from at least one exhaust gas generating facility to be introduced thereto, wherein the extension tube 11 has a cross section extended in a tapered shape, and the buffer tank 1 extends vertically downwardly from the extension tube 11; a horizontal distribution pipe 2 connected at one side to the other side of the buffer tank 1 in such a manner as to extend in a horizontal direction; a plurality of membrane separation filters 3, each connected at a lower end to the horizontal distribution pipe 2 and including a separation membrane extending vertically upwardly so that a nitrogen gas having a small particle size passes therethrough and an impurity gas containing the perfluoro compound does not pass therethrough, the membrane separation filters being spaced apart from each other at predetermined intervals; an impurity gas discharge conduit 4 configured to collect the impurity gas that does not pass through the separation membranes in the plurality of membrane separation filters 3, and transfer the collected impurity gas to a retreatment chamber; a first nitrogen gas recycling conduit 5 having a first vacuum pump 51 and an auxiliary membrane separation filter 52 mounted thereon, so that the first vacuum pump 51 collects the nitrogen gas that passes through the separation membranes in the plurality of membrane separation filters 3 and sucks the collected nitrogen gas, and the auxiliary membrane separation filter 52 re-separates the nitrogen gas sucked by the first vacuum pump 51 so as to allow the impurity gas to be discharged to the impurity gas discharge conduit 4 and the nitrogen gas to be transferred for recycling; a second nitrogen gas recycling conduit 6 having a second vacuum pump 61 mounted thereon so that the second vacuum pump 61 sucks the nitrogen gas passing through a separation membrane in the auxiliary membrane separation filter 52 and allows a high-purity nitrogen gas sucked thereby to be transferred for recycling; and a return conduit 7 having first and second detection sensors 71 and 72 and first and second three-phase valves 73 and 74 mounted thereon so that the first and second detection sensors 71 and 72 detect sulfur hexafluoride and nitrogen trifluoride of the conduit immediately after passing through the first and second vacuum pumps 51 and 61 of the first and second nitrogen gas recycling conduits 5 and 6, and the return conduit 7 collects sulfur hexafluoride and nitrogen trifluoride after selectively being connected to the conduits 5 and 6 immediately after sulfur hexafluoride and nitrogen trifluoride pass through the first and second vacuum pumps 51 and 61 by means of the first and second three-phase valves 73 and 74, respectively, so as to allow sulfur hexafluoride and nitrogen trifluoride to be re-introduced into the buffer tank 1. |
