478961 A7 B7 五、發明說明（1 ) (發明所屬之技術領域） 本發明係關於一種全氯化化合物（perflu〇r〇c〇mp〇unds :PFC )氣體之處理方法及處理裝置。 (以往之技術） PFC 係 CF4、C 2 F 6 . C a F 8 . SF6、NF3 等 之總稱。P F C氣體係使用半導體蝕刻用氣體，半導體洗 滌用氣體或絕緣氣體等。該P F C氣體地球溫室化氣體， 成爲放出大氣之規則對象。所以被檢討各種分解方法。作 爲該分解方法之一種’在日本特開平1 1 一 7 0 3 2 2號 公報。記載著加水分解P F C氣體之後，以水或鹼水溶液 施以洗滌並加以排氣之方法。 - (發明欲解決之課題） 本發明人係在硏究分解P F C氣體，並洗滌分解氣體 後加以排氣之P F C處理方法中，發現藉由洗滌氣體會腐 蝕排出洗滌氣體之排氣風扇或排氣管。 本發明係在P F C氣體之處理方法及處理裝置中，藉 由洗滌P F C分解氣體之後的氣體，抑制排氣風扇及排氣 管被腐蝕。 (解決課題所用之手段） 本發明係洗滌P F C之分解氣體之後，經分離包含於 氣體中含有P F C分解生成物之霧後施行排氣。 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） -------!·裝1 (請先閱讀背面之注音？事項再填寫本頁) 訂---- 争· 經濟部智慧財產局員工消費合作社印製 478961 經濟部智慧財產局員工消費合作社印製 A7 B7 五、發明說明（2 ) 本發明人係查明了排氣管及排氣風扇之腐蝕原因，爲 在洗滌過程未被洗滌之P F c分解氣體f，與霧一起流至洗 滌塔之塔外，而附著在風爵或排(氣管％導致。藉著分離霧 ’成功地抑制排氣管及排氣風管之腐蝕。 包含於洗滌後之氣體的霧係粒徑1 〇 # m以上者佔大 部分，而粒徑1 // m以下者係最多不過數十％。除去具此 等粒倥分布之霧’適用旋風式分離裝置，過濾式分離裝置 ’電氣集塵裝置及活性碳吸附裝置等。尤其是旋風式分離 裝置與過濾式分離裝置係坪將裝置成爲小型化而較理想。 使用過濾式分離裝置時，重疊孔徑不用之複數枚過濾片， 以孔徑大之過濾片分離粒徑大之霧。而以孔徑小之過濾片 分離粒徑小之霧較理想。若僅使用孔徑小之過濾片，會使 氣體流通變壞，壓損變大，由於必須使用大型風扇，因此 不太理想。藉著組合孔徑不同之複數枚過濾片，成爲可將 壓損抑制成較小。 本發明係可適用在將P F C氣體藉著加水分解、氧化 分解、燃燒或熱分解等分解成含有氟化氫之氣體後經洗滌 加以排氣之方法。在此等方法以外，只要能將P F C分解 丄 · 成含有氟化氫.έ氣體之方法，也可適用本發明之處理方法 。藉著將P F C轉換成氟化氫，並藉由以水或鹼水溶液施 行洗滌能將氟化氫吸收在溶液中，成爲可從氣體中加以除 去’可將從洗滌塔所排出之氣體成爲實質上未含有氟化物 之氣體。 又洗滌排氣後施以分解霧之先行技術係記載於日本特 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） -----------裝-----^----訂--------- (請先閱讀背面之注意事項再填寫本頁) 478961 經濟部智慧財產局員工消費合作社印製 Α7 Β7 五、發明說明（3 ) 開平1 1 — 2 1 6 4 5 5號公報，惟未將P F C分解氣體 作爲對象。在日本特開平8 - 3 1 8 1 2 2號公報及特開 昭5 7 — 1 9 7 0 2 3號公報，記載著在水洗滌裝置之後 設置吸附塔，惟也未將P F C分解氣體作爲對象。 (發明之實施形態） 加水分解S F 6或N F 3時，理論上進行式（1 )及式 (2 )之反應。 SF6+3H2〇->S〇3+6HF (式 1) 2NF3+3H2〇->NO + N〇2+6HF (式 2) 分解生成物之S〇3、 HF、 NF3、 H2〇係在洗滌 塔，藉由水或鹼水溶液施行洗滌而由氣體中被除去。但是 ，未被除去之一部分之HF、 SO 3、1^〇2等係與：《2〇 一起成爲霧而通過洗淨塔。例如知道S〇3 1 m ο 1係同 伴約2 5 0 m ο 1 Η 2 0。此等霧被排出至排氣線路，則 排氣溫度成爲霧點以下時凝結，附著於排氣管內面會產生 阻塞。又附著於排氣風扇之內部使風扇無法使用。處理 N F 3時，在洗滌時也產生硝酸之霧，將此流在排氣線路會 腐蝕排氣管等。處理碳系之P F C氣體時，腐鈾排氣管或 排氣風扇之氣體係主要爲H F。 含在通過洗滌塔之排氣之霧係成爲多少粒徑’使用衝 擊器方式之粒徑測定器加以調查。結果，霧之粒徑係1 1 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） --------I.——•裝----l·——訂-------- (請先閱讀背面之注意事項再填寫本頁) 4478961 A7 B7 五、發明說明（4 ) // m以上者有約6 0 %，1 // m以下者有約3 0 %，剩餘 係1〜1 0//m者。 旋風式霧分離裝置係使用離心力來除去氣流中之小固 體粒子或液滴之裝置。將旋風式分分離裝置之槪略圖表示 於第2 A圖與第2 B圖。第2 A圖係俯視圖；第2 B圖係 側面之剖視面。該旋風式霧分離裝置2 1係將含有霧之氣 體從氣體入口 2 2以高速被導入至旋風分離器內部。被導 入至旋風分離器內部之霧係藉離心力被放出至外側而踫到 圓筒之內壁2 3。踫到內壁2 3之霧係從下部液排出口 2 4被排出。除去霧之氣體係上昇後通過內筒2 6而從上 部氣體排出口排出。含於通過內筒2 6之氣體的液體係從 液排出口 2 5被排出。旋風分離器之大小（內壁2 3之最 大徑部分之大小），係藉由除去液滴粒徑來決定較佳。氣 體入口 2 2之內徑小，氣體之入口速度大則離心力變大， 因而可除去小霧。例如欲捕捉約1 // m之霧，則將氣體入 口之半徑作爲約1 c m，入口氣體速度作爲約2 0 m / s e c較理想。旋風分離器之入口氣體流速係1 〇〜3 〇 m / s e c較理想。作成該範圍，能得到高除霧比率。入 口速度愈大則除霧比率會增大，惟壓損會變大。作爲旋風 分離器之材質，以耐蝕性優異之氯乙烯、丙烯酸酯等較理 想。 過濾式霧分離裝置係藉由使用具有細孔之過濾片來捕 捉氣體流動中之霧者。將過濾式霧分離裝置之槪略圖表示 於第3圖。第3圖係表示重疊孔徑不同之兩枚過濾片3 2 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） (請先閱讀背面之注意事項再填寫本頁)478961 A7 B7 V. Description of the invention (1) (Technical field to which the invention belongs) The present invention relates to a method and a device for treating perfluor compounds (PFC) gas. (Previous technology) PFC is the general name of CF4, C 2 F 6. C a F 8. SF6, NF3, etc. The P F C gas system uses a semiconductor etching gas, a semiconductor cleaning gas, or an insulating gas. This P F C gas is a global greenhouse gas, and has become a regular target for releasing the atmosphere. Therefore, various decomposition methods have been reviewed. As one of the decomposition methods, it is disclosed in Japanese Patent Application Laid-Open No. 1 1 to 7 0 3 2. The method of decomposing P F C gas by water, washing with water or an alkaline aqueous solution, and exhausting the gas is described. -(Problems to be Solved by the Invention) The inventors found that the exhaust fan or exhaust gas which erodes the cleaning gas will be corroded by the cleaning gas in the PFC processing method which studies the decomposition of the PFC gas and then scrubs the decomposed gas and exhausts it. tube. The present invention relates to a method and a device for treating a P F C gas, by suppressing the exhaust fan and the exhaust pipe from being corroded by washing the P F C decomposed gas. (Means for solving the problem) The present invention is to wash the decomposed gas of P F C, and then separate the mist containing P F C decomposed products contained in the gas, and then exhaust it. This paper size applies to China National Standard (CNS) A4 specification (210 X 297 mm) -------! · Packing 1 (Please read the phonetic on the back? Matters before filling out this page) Order ---- contend · Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, printed by 478961 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, printed by A7 B7 The PF c decomposed gas f that was not washed during the washing process flows out of the tower of the washing tower together with the mist, and attaches to the wind or exhaust pipe (caused by air ducts. By separating the mist, the exhaust pipe and exhaust gas are successfully suppressed Corrosion of air ducts. The mist particle size of the gas containing more than 10 # m is the majority, and the particle diameter of 1 / m or less is at most tens of%. The mist is applicable to cyclone-type separation device, filter-type separation device, electric dust collection device, activated carbon adsorption device, etc. Especially, the cyclone-type separation device and filter-type separation device are ideal for miniaturizing the device. Use of filter-type separation When installing, do not use overlapping apertures For several filters, use a filter with a large pore size to separate the mist with a large particle size. Use a filter with a small pore size to separate the mist with a small particle size. If only the filter with a small pore size is used, the gas flow will be deteriorated. The pressure loss becomes large, and it is not ideal because a large fan must be used. By combining a plurality of filters with different apertures, the pressure loss can be suppressed to a small value. The present invention is applicable to decompose PFC gas by adding water. , Oxidative decomposition, combustion or thermal decomposition and other methods to decompose into hydrogen fluoride-containing gas and then wash and exhaust. In addition to these methods, as long as it can decompose PFC into hydrogen fluoride-containing gas, this method can also be applied The treatment method of the invention. By converting PFC to hydrogen fluoride and washing it with water or an alkaline aqueous solution, the hydrogen fluoride can be absorbed into the solution and can be removed from the gas. The gas discharged from the washing tower can be made into a substance. The gas that does not contain fluoride. The advanced technology of washing the exhaust gas and applying the decomposition mist is described in Japanese special paper. The standard of China (CNS) A is applicable. 4 specifications (210 X 297 mm) ----------- install ----- ^ ---- order --------- (Please read the precautions on the back first (Fill in this page) 478961 Printed by the Consumers ’Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs Α7 Β7 V. Description of Invention (3) Kaiping No. 1 1-2 1 6 4 5 5 but does not target PFC decomposed gas. 8-3 1 8 1 2 and JP 5-7-197 7 0 2 3 describe the installation of an adsorption tower after a water washing device, but do not target PFC decomposed gas. (Invention of Embodiment) When SF 6 or NF 3 is hydrolyzed, the reaction of the formula (1) and the formula (2) theoretically proceeds. SF6 + 3H2〇- > S〇3 + 6HF (formula 1) 2NF3 + 3H2〇- > NO + N〇2 + 6HF (formula 2) S03, HF, NF3, H2〇 The washing tower is removed from the gas by washing with water or an aqueous alkali solution. However, a part of HF, SO 3, 1 ^ 〇2, etc., which has not been removed, and: "2〇 together become mist and pass through the washing tower. For example, it is known that S03 1 m ο 1 is about 2 5 0 m ο 1 Η 2 0. When these mists are discharged to the exhaust line, the exhaust gas will condense when the temperature becomes below the fog point, and the inner surface of the exhaust pipe will be blocked. It is attached to the inside of the exhaust fan, making the fan unusable. When treating N F 3, a mist of nitric acid is generated during washing, and this flow on the exhaust line will corrode the exhaust pipe and the like. When processing carbon-based P F C gas, the gas system of the rotten uranium exhaust pipe or exhaust fan is mainly H F. How large is the particle size of the mist system contained in the exhaust gas passing through the scrubber tower? As a result, the particle size of the fog is 1 1 This paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) -------- I .—— • Installation ---- l · —— Order -------- (Please read the notes on the back before filling this page) 4478961 A7 B7 V. Description of the invention (4) // Above 60 m, about 60%, 1 // below m About 30%, the remainder is 1 ~ 10 // m. Cyclone type mist separation device is a device that uses centrifugal force to remove small solid particles or droplets in the air flow. The schematic diagrams of the cyclone type separation device are shown in Figs. 2A and 2B. Figure 2A is a top view; Figure 2B is a side cross-sectional view. This cyclone-type mist separation device 21 introduces a gas containing mist from the gas inlet 22 into the cyclone separator at a high speed. The mist introduced into the interior of the cyclone is released to the outside by centrifugal force and hits the inner wall 23 of the cylinder. The mist from the inner wall 23 is discharged from the lower liquid discharge port 24. The mist-removing gas system rises through the inner cylinder 26 and is discharged from the upper gas discharge port. The liquid system containing the gas passing through the inner cylinder 26 is discharged from the liquid discharge port 25. The size of the cyclone (the largest diameter part of the inner wall 23) is determined by removing the particle diameter of the droplet. The inner diameter of the gas inlet 22 is small, and the centrifugal force becomes large when the gas inlet speed is large, so small mist can be removed. For example, if you want to capture a mist of about 1 // m, the radius of the gas inlet is about 1 c m, and the gas velocity at the inlet is about 20 m / s e c. The inlet gas flow rate of the cyclone separator is ideally 10 ～ 300 m / sec. With this range, a high defogging ratio can be obtained. The higher the inlet speed, the higher the defogging ratio, but the larger the pressure loss. As the material of the cyclone separator, vinyl chloride, acrylate and the like having excellent corrosion resistance are preferred. The filter type mist separation device captures mist in a gas flow by using a filter sheet having fine holes. Fig. 3 is a schematic view of a filter type mist separation device. Figure 3 shows two filters with different overlapping apertures. 3 2 This paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) (Please read the precautions on the back before filling this page)
裝 ----^----訂---II 爭 經濟部智慧財產局員工消費合作社印製 478961 A7 B7 五、發明說明（5 ) 、3 3之例子。該過濾式霧分離裝置3 0係在筒內之大約 中央部設置過濾片32、 33，從下部導入氣體，而從上 部排出者。過濾片3 2、3 3係藉由襯墊3 4、凸緣3 5 被固定在筒。與通過過濾片之氣體同伴之液體，係由液排 出口 3 6朝筒外排出。 在過濾片之氣體速度爲5〜2 5 cm/s e c時，欲 除去1 // m之霧，使用2 5 0 # m以下之細孔尺寸的過濾 片較理想，尤其是使用1 6 0 # m以下之過濾片較理想。 在使用過濾片時，若細孔尺寸過大會降低霧之除去比率， 而過小則除去比率較高惟壓損變大。過濾片之材質，以市 售之玻璃製者就可以，惟在氣體中含有H F等酸性氣體時 ，則以陶瓷製較理想。使用過濾片時，也可設在排氣洗滌 塔內。例如在比噴霧式洗滌塔之噴嘴上方設置過濾片，來 除去含於氣體之霧。 電氣集塵裝置係將氣體流在具強度之電場中使之帶電 而在相反之電極部分收集霧之裝置。將電氣集塵裝置之槪 略圖表示於第4圖。該電氣集塵裝置4 0係藉由上下地配 置之放電極支持棒4 1、4 2來支持放電極4 4，相對於 放電極設置圓筒狀集塵極4 3者。放電極與集塵極係被連 接於高電壓電源4 5。被處理氣體係從下部氣體入口進入 而從上部排出。又從氣體中被分離之液體係由液排出口 4 6被排出。電氣集塵裝置時，，施以8 k V以上之電壓較 理想。又在電極部不會附著霧地流通空氣等較理想。若霧 附著於電極，則藉由短路使電壓無法上昇。在電氣集塵之 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） -----------^ — (請先閱讀背面之注意事項再填寫本頁) 訂---- 秦！ 經濟部智慧財產局員工消費合作社印製 478961 A7 B7 經濟部智慧財產局員工消費合作社印製 五、發明說明（6 ) 電極可使用鎢線或s V S線等。 活性碳吸附、裝置係將霧吸附在活性碳之方式。將活性 碳吸附裝置之槪略圖表示於第5圖’。第5圖之活性碳吸附 裝置係具有塡充活性碳5 9之兩具吸附、再生塔5 1、 5 2，其中一方在吸附過程時，另一方則在再生過程。在 吸附時，氣體係從活性碳5 9之下方進入吸附、再生塔內 ，經活性碳後朝上方排出。在再生時，將水1 0從注入口 5 3供給至塔內，洗掉附著於活性碳之霧而由液排出口 5 4排出至塔外。然後，爲了乾燥活性端，從吸氣口 5 5 將空氣供給至塔內1，藉由吸氣風扇5 7從排氣口 5 6排出 成爲排氣5 8。活碳性層之氣體空間速度係3 0 0〜 4 0 0 h — 1較理想，處理氣體流量爲約7 5 1 / m i η 時，則約1 0〜1 5 L之活性碳就充分。爲了活性碳之再 生而流之水係經常地流動也可以，或是在塔內儲水而在再 生活性碳時使之流動也可以。霧含有S 0 3等時，則硫酸吸 附在活性碳上。在該活性碳之再生處理所使用之水有硫酸 溶入；惟因可吸收S 0 2，因此可將排氣回流至洗滌塔。但 若p Η値降低則成爲無法吸收S 0 2，因此被要求p Η之管 理。 藉由旋風，過濾等霧除去裝置除去霧時，被導入霧除 去裝置之氣體之流量管理也很重要。減少被導至P F C分 灕裝置之氣體量，結果，減少被導至霧除去裝置之氣體流 量時，加入不洩漏氣體等而將氣體流量配合所定流量（設 計霧分解裝置時所使用之設定流量）較理想。活性碳吸附 (請先閱讀背面之注意事項再填寫本頁) 裝 訂---- 暮_ 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） 478961 A7 ____B7_ 五、發明說明（7 ) 裝置時，即使減少氣體流量，也由於接觸時間成爲較久而 霧除去性能不身下降，因此不需要流量管理。 (請先閱讀背面之注音？事項再填寫本頁) 以下，使用圖式說明本發明之實施形態。但是本發明 係並不被限定於以下所述者。 第1圖係表示將本發明之處理裝置設在半導體蝕刻爐 之例子。 在鈾刻爐9 9中，在經減壓之蝕刻爐內藉由S F 6等之 P F C氣體1 〇 〇施行半導體晶圓之蝕刻。結束鈾刻’則 一以真空泵（未圖示）吸引爐內，使P F C被排出。在該時 ，爲了保護泵而在泵流通N 2，俾將P F C濃度稀釋至數％ 〇 經濟部智慧財產局員工消費合作社印製 蝕刻爐之排氣係在被導至p F C分解塔1之前，在塡 充塑膠等粒子之塡充塔1 0 1來除去固態物，並在噴霧塔 1 0 2除去水溶成分。通過噴霧塔1 〇 2之氣體，係以預 熱器2加熱至P F C分離溫度爲止。由於本實施例之 P F C分解塔1係加水分解？？（：之方式者，因此在預熱 器2供給經過空氣3與離子交換樹脂1 〇 3之水1 0。水 1 0係在預熱器2被汽化。預熱器2出口之P F C濃度係 約0 · 1〜1 %較理想，水蒸汽係對.於氟、化合物之m ο 1 v 數，調節成2 5,〜10 0倍較理想。空、氣3，係釋加成疼屬 氣體中之氧、氣濃度爲約4 %較隹。此等混合1氣體亦即反應 氣體，係被導至設於預熱器2之出口的PFC分解塔1。 在本實施例中，假設P F C爲S F6或含有S F 6之氣體’ 而在P F C分解塔1塡充有P F C分艉眉化劑8與有害成 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） -10 - 478961 Α7 Β7 五、發明說明（8 ) 分除去催化劑9。在此之有害成分爲揩C〇、S〇2、F 2 等。混合氣體係例如在空間速度1 0 0 0 h - 1 ，反應溫 (請先閱讀背面之注意事項再填寫本頁) 度6 5 0〜8 5 0 °C之條件下與催化劑接觸。又，空間速 度（h — 1 )係以反應氣體流量（m 1 / h ) / (催化劑量 (4 )所求得之數値。在p F C分解塔，係藉著電爐等加 熱器6來加熱催化劑或反應氣體較佳。排出P F C分解塔 1之分解氣體係被導至冷却室1 1 ，藉由噴嘴所噴霧之水 1 0被冷却。通過冷却室之氣體係在排氣洗滌塔1 3將 H F及水溶成分藉由吸收在水1 〇而被除去，之後被導至 霧除去裝置。在本實施例係在排氣洗滌塔1 3放進吸附劑 等之塡充材1 2，俾提高氣體與水之接觸效率。又具備旋 風式之霧分離裝置2 1。被除去霧之氣體係以風扇1 6吸 引作爲排氣1 7被放出至大氣中。在排氣洗滌塔1 3被吸 收H F等之排水2 0係被儲在排水槽1 8之後，藉由排水 泵1 9被排出。排出2 0係在半導體工廠以既設之排液處 理設備成爲無害化也可以。又，以旋風分離器分離之霧’ 也儲在排水槽較理想。 在P/ F C分解催化劑8，可使用含有例如A 1與從 經濟部智慧財產局員工消費合作社印製Equipment ---- ^ ---- Order --- II Competition Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 478961 A7 B7 V. Examples of invention description (5) and 33. The filter type mist separation device 30 is provided with filter pieces 32 and 33 at approximately the center of the cylinder, and the gas is introduced from the lower part and discharged from the upper part. The filter pieces 3 2 and 3 3 are fixed to the cartridge by a gasket 3 4 and a flange 3 5. The liquid accompanying the gas passing through the filter is discharged from the liquid discharge port 36 to the outside of the cartridge. When the gas velocity of the filter is 5 ~ 2 5 cm / sec, to remove the mist of 1 // m, it is ideal to use a filter with a pore size below 2 5 0 # m, especially using 1 6 0 # m The following filters are preferred. When the filter is used, if the pore size is too large, the mist removal ratio is reduced, while if it is too small, the removal ratio is high but the pressure loss becomes large. The material of the filter can be made of commercially available glass, but when the gas contains acidic gas such as H F, it is preferable to use ceramic. When using a filter, it can also be installed in an exhaust scrubber. For example, a filter is installed above the nozzle of the spray-type washing tower to remove the gas-containing mist. The electric dust collecting device is a device that charges a gas in a strong electric field and collects the mist at the opposite electrode portion. The schematic diagram of the electric dust collector is shown in FIG. 4. This electric dust collection device 40 supports the discharge electrode 44 by the discharge electrode support rods 4 1 and 4 2 arranged up and down, and a cylindrical dust collection electrode 43 is provided for the discharge electrode. The discharge electrode and the dust collecting electrode are connected to a high-voltage power source 45. The processed gas system enters from the lower gas inlet and exits from the upper. The liquid system separated from the gas is discharged from the liquid discharge port 46. For an electric dust collector, it is ideal to apply a voltage of 8 k V or more. In addition, it is preferable to circulate air or the like without adhering mist to the electrode portion. If the mist adheres to the electrode, the voltage cannot be increased by a short circuit. Applicable to China National Standard (CNS) A4 specification (210 X 297 mm) for the paper size of electrical dust collection ----------- ^-(Please read the precautions on the back before filling this page) Order ---- Qin! Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 478961 A7 B7 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 5. Description of the invention (6) The electrodes can be tungsten wires or s V S wires. Activated carbon adsorption, device is a method of adsorbing mist on activated carbon. The outline of the activated carbon adsorption device is shown in Fig. 5 '. The activated carbon adsorption device in Fig. 5 has two adsorption and regeneration towers 5 1 and 5 2 filled with activated carbon 5 9, one of which is in the adsorption process and the other is in the regeneration process. At the time of adsorption, the gas system enters the adsorption and regeneration tower from below the activated carbon 59, and is discharged upward after passing through the activated carbon. During regeneration, water 10 was supplied into the tower from the injection port 53, and the mist adhering to the activated carbon was washed away and discharged from the liquid discharge port 54 to the outside of the tower. Then, in order to dry the active end, air is supplied into the tower 1 from the suction port 5 5 and exhausted from the exhaust port 5 6 by the suction fan 57 to become the exhaust gas 5 8. The gas space velocity of the activated carbon layer is preferably from 300 to 400 h—1. When the processing gas flow rate is about 7 5 1 / m i η, about 10 to 15 L of activated carbon is sufficient. The water system flowing for the regeneration of activated carbon may flow frequently, or the water may be stored in the tower and allowed to flow when regenerating carbon. When the mist contains S 0 3 or the like, sulfuric acid is adsorbed on the activated carbon. The water used in the regeneration treatment of the activated carbon has sulfuric acid dissolved in it, but because it can absorb S 0 2, the exhaust gas can be returned to the washing tower. However, if p Η 値 decreases, it becomes impossible to absorb S 0 2, so management of p Η is required. When mist is removed by a mist removal device such as a cyclone or filter, the flow rate management of the gas introduced into the mist removal device is also important. Reduce the amount of gas that is led to the PFC separating device. As a result, when reducing the gas flow that is led to the mist removal device, add a leak-free gas, etc., and match the gas flow with the set flow (the set flow used when designing the mist decomposition device) More ideal. Activated carbon adsorption (please read the precautions on the back before filling this page) Binding _ twilight _ This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 478961 A7 ____B7_ V. Description of the invention ( 7) When the device is installed, even if the gas flow rate is reduced, since the contact time becomes longer, the mist removal performance does not decrease, so no flow management is required. (Please read the Zhuyin on the back? Matters before filling out this page.) The following describes the embodiment of the present invention using drawings. However, the present invention is not limited to the following. Fig. 1 shows an example in which the processing apparatus of the present invention is installed in a semiconductor etching furnace. In the uranium engraving furnace 99, the semiconductor wafer is etched with a P F C gas such as S F 6 in a reduced-pressure etching furnace. At the end of the uranium engraving process, a vacuum pump (not shown) is used to suck the inside of the furnace, and P F C is discharged. At this time, in order to protect the pump, N 2 was flowed through the pump, and the concentration of PFC was diluted to several%. 0 The exhaust gas of the etching furnace printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs was led to the p FC decomposition tower 1 Solids are removed in the filling tower 1101 of particles filled with plastic and the like, and water-soluble components are removed in the spray tower 1102. The gas passing through the spray tower 102 was heated by the preheater 2 to the P F C separation temperature. Because the P F C decomposition tower 1 of this embodiment is hydrolyzed? ? (: Method, so the preheater 2 is supplied with water 10 passing through the air 3 and the ion exchange resin 1 0. The water 10 is vaporized in the preheater 2. The PFC concentration at the outlet of the preheater 2 is about 0 · 1 ~ 1% is ideal, water vapor is ideal for fluorine, compounds m ο 1 v, adjusted to 25, 5 ~ 10 0 times. Air, air 3, the release of the pain is a gas The concentration of oxygen and gas is about 4%. The mixed 1 gas, that is, the reaction gas, is led to the PFC decomposition tower 1 provided at the outlet of the preheater 2. In this embodiment, it is assumed that the PFC is S F6 or a gas containing SF 6 ', and the PFC decomposition tower 1 is filled with PFC separating agent 8 and harmful costs Paper size Applies Chinese National Standard (CNS) A4 (210 X 297 mm) -10-478961 Α7 Β7 V. Description of the invention (8) The catalyst 9 is removed. The harmful components here are 揩 C〇, S〇2, F 2 and so on. The mixed gas system is, for example, at a space velocity of 1 00 h-1 and the reaction temperature (please Read the precautions on the back before filling in this page.) Contact the catalyst at a temperature of 6 50 ~ 8 5 0 ° C. The space velocity (h — 1) is based on the reaction gas. Flow rate (m 1 / h) / (catalyst amount (4)) 値. In the p FC decomposition tower, it is better to heat the catalyst or reaction gas by a heater 6 such as an electric furnace. The PFC decomposition tower 1 is discharged. The decomposed gas system is guided to the cooling chamber 1 1 and is cooled by the water sprayed by the nozzle 10. The gas system in the cooling chamber is used in the exhaust washing tower 13 to absorb HF and water-soluble components by being absorbed in the water 10. After being removed, it is led to a mist removing device. In this embodiment, a plutonium filling material 12 such as an adsorbent is placed in the exhaust washing tower 13 to improve the contact efficiency of gas and water. It also has a cyclone-type mist separation. Device 2 1. The mist-removed gas system is attracted by the fan 16 as the exhaust gas 17 and released into the atmosphere. The exhaust washing tower 13 is drained by HF and the like, and the drainage system 20 is stored in the drainage tank 18 It is discharged by the drainage pump 19. The drainage 20 can be rendered harmless in the semiconductor factory by the existing drainage treatment equipment. Also, the mist separated by the cyclone separator is also stored in the drainage tank. / FC decomposition catalyst 8, which can be used containing, for example, A 1 and a member of the Intellectual Property Bureau from the Ministry of Economic Affairs Printed consumer cooperatives
Zn、Ni、Ti、Fe、Sn、Co、Zr、Ce、 'S i、P t、P d中所選擇之至少一種之催化劑，惟並不 被限定於此等者。此等P F C分解催化劑係以氧化物、金 屬或複合氧化物等形式可使用。A 1%〇3與N i、Ζ η、 ( T i之至少一種所構成之催化劑係具有高分解性能’因此 ί - ' ' 更理想。 _ 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） 478961 A7 B7 五、發明說明（9 ) 作爲洗滌塔，均可適用噴霧水或鹼水溶液之方式，或 在此等液中使分解生成氣體產生起泡之方式或是在洗滌塔 內塡充吸附劑或K〇H、 Na〇H、 Ca (〇H)2、A catalyst of at least one selected from the group consisting of Zn, Ni, Ti, Fe, Sn, Co, Zr, Ce, 'S i, P t, and P d is not limited to these. These P F C decomposition catalysts can be used in the form of oxides, metals or composite oxides. A 1% 〇3 and at least one of Ni, Z η, and T i catalysts with high decomposition performance 'hence--' is more ideal. _ This paper size applies Chinese National Standard (CNS) A4 specifications ( (210 X 297 mm) 478961 A7 B7 V. Description of the invention (9) As a washing tower, spraying water or an alkaline aqueous solution can be applied, or a method of foaming the decomposition gas in these liquids can be used or washing The column is filled with adsorbent or K〇H, Na〇H, Ca (〇H) 2,
Mg (OH)2等之鹼性固體未補充分解氣體之方式者等任 何一種方式。在此等之中，噴霧方式之洗滌塔係效率高， 具在洗滌塔內不容易發生結晶析出等所產生之阻塞，故最 理想。 在來自洗滌塔之排氣線路，由於流動腐鈾性氣體，因 此以如氯化乙烯或是丙烯酸酯樹脂等高耐蝕性之材質者所 製作，或是在此等材質之內面施以塗敷者所製作較理想。 排氣風扇也同樣。 (實施例1 ) 從第1圖之P F C處理裝置除掉蝕刻爐9 9、塡充塔 101、噴霧塔102者，施行SF6之處理。在SF6添 加氮氣而將S F6之濃度稀釋成約5 0 0 0 P pm。在該稀 釋氣體添加空氣3，而在預熱器2施以加溫。水蒸汽係將 離水交換水成爲理論量之3 3〜3 7倍地導進預熱器2使 之汽化。將如此地經調整之反應氣體，導進藉加熱器6施 以加熱之P F i C分解塔！L，並與S F 6分解催化劑及 S〇2 F 2分解催化劑接觸。在S F 6分觸催化劑使用N i 1 / t 與A 1 2〇3所構成之催化劑，而在S 0 2. F 2分解催化齊il使 用P d與L a及A 1 2〇3所構成之催化劑。將此等催化劑 之溫度係保持在7 0 0〜8 0 〇 °C。反應氣體之空間速度 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） (請先閱讀背面之注音？事項再填寫本頁) 裝-----^----訂---- 蠢· 經濟部智慧財產局員工消費合作社印製 -12 478961 κι Β7 五、發明說明（10 ) (請先閱讀背面之注意事項再填寫本頁) 係作爲1 0 0 〇 h - 1。排出排氣洗滌塔之氣體係在入口速 度約2 0 m / s e c之條件下，導進內徑（最大徑部分） 24mm，高度1 1 imm之旋風式霧分離裝置2 1。在 旋風式霧分離裝置，使用表示於第2 A圖及第2 B圖之構 造者。液排出口 2 4之內徑係1 4mm。排氣風扇之葉片 部分係環氧系耐蝕性材質而施以塗敷。 測定旋風式霧分離裝置之前後之氣體中的S 0 3濃度， 算出除霧比率。又S 0 3濃度係從使用液體捕集法所測定之 S〇X濃度，減去使用氣體色層分析儀所測定之S〇2濃度 之數値。結果，在霧分離裝置正前方之S〇3濃度爲1 5 3 P pm者’通過霧分離裝置後成爲3 〇 p pm，被除去 8 0 %之霧。試驗後置放一天，拆卸排氣風扇1 6並未被 認出有腐蝕。 供做試驗之催化劑之調配法係如下。 拳 含有N i之A 1 2〇3催化劑： 經濟部智慧財產局員工消費合作社印製 在1 2 0 °C溫度下乾燥市售之水軟鋁石（boelhmite ) 粉末一小時。將溶解硝酸鎳6水和物2 1 0 · 8 2 g之水 溶液添加在該乾燥粉末2 0 0 g上，並加以混涅。混湼後 ，在2 5 0〜3 0 0 °C下乾燥約兩小時，在7 0 0 °C燒成 兩小時。將燒成物施行粉碎並經篩選作爲〇 · 5〜1 m m 粒徑。完成後之催化劑組成係在原子比成爲A 1 : N i = 80: 20 (mol%) 〇 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公爱） 478961 A7 B7 五、發明說明（） 含有Pd、La之Al2〇3催化劑： 將市售之2〜4 m m粒徑之粒狀A 1 2〇3 (日本住友 化學製，NKHD— 24)破碎成0 · 5〜1mm，在 1 2 0 °C下乾-燥一小時.。之後將溶解硝酸鑭6水和物之溶 , ^ ' 液含浸成爲L a 2〇3重量1 0 w t %。亦即’將硝酸鑭6 和物2 6 · 8 4 g溶解於純水並含浸在A 1 2〇3 1 0 0 g之後，在1 2 0 °C下乾燥兩小時並施行燒成。將 此作爲含有L a之A 1 2〇3。在燒成後之含有L a之 A 1 2〇3，含浸硝酸鈀溶液使P d重量成爲0 · 5 w t % 。具體而言，對於含有La之Al2〇3 100g’將 4 · 4 3 9 w t %硝酸鈀溶液1 1 · 2 6 g溶解於純水並 施以含浸。含浸後，在1 2 0 °C下乾燥兩小時並施以燒成 〇 (比較例） 在實施例1不使用霧分離裝置，又在除了風扇之塗敷 之外的狀態施行同樣之實驗。結果，在風扇內有霧，在吸 排氣口儲存溶有S 0 3之酸性水。結束試驗置放一天，在風 發生腐蝕生成物，有氣體流路之阻塞。又固裝腐蝕生成物 使風扇無法起動。 (實施例2 ) 、 在實施例1中，在霧分離裝置使用表示於第3圖之過 濾式者而施行同樣之實驗。過濾式霧分離裝置係筒內徑 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） (請先閱讀背面之注意事項再填寫本頁) 裝-----^----訂---- 經濟部智慧財產局員工消費合作社印製 478961 經濟部智慧財產局員工消費合作社印製 A7 B7 五、發明說明（12 ) 7 9mm，高度5 0 〇mm之圓筒型者，在其大約中心（ 2 5 0 m m之高度）設置凸緣並設置過濾片3 2、3 3。 所使用之過濾片係市售之玻璃製，重疊兩枚細孔徑爲 1 0 0〜1 6 0 之過濾片3 2與孔徑爲1 6 0〜 2 5 0 // m之過濾片3 3。過濾片之厚度係兩枚合計爲 1 Omm。過濾片部之氣體速度係作爲2 4 cm/s e c 。結果，進入霧分離裝置前之S〇濃度爲1 3 8 p p m者 ，通過霧分離裝置後係成爲1 6 p p m，ffii除霧比率係成 爲8 8 %。試驗後置放一天，拆卸排氣風扇並未被認出有 腐蝕。 (實施例3 ) 在霧除去裝置使用表示於第4圖之構造的電氣集塵裝 置，施行與實施例1同樣之實驗。 電氣集塵裝置係在內徑4 5 mm之氯化乙烯製圓筒內 ，設置內徑3 5mm，長度1 1 〇mm之管狀SUS製集 塵極。又將直徑0 · 1 4 8 m m之鎢製放電極設於圓筒之 中心。放電極係使用直徑3 m m之S U S製放電極支持棒 在上下加以支持。將直流高電壓電源（1 〇 k V，1 〇 〇 // A )連接於放電極及集電極。 將電壓作爲8 k V，與實施例1v同樣地施行s F 6之分 解處理之結果，洗滌塔出口之S〇3濃度爲1 4 0 p p m者 ’在電氣集塵裝置出口成爲4 2 p p m，而除_化比率爲 7 0 %。試驗傻置放一天，拆卸排氣風扇並未被認出有腐 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公髮） ------—— ！ 裝-----：---—訂·-----I I (請先閱讀背面之注意事項再填寫本頁) 478961 經濟部智慧財產局員工消費合作社印製 A7 B7 五、發明說明（13 ) 蝕。 (實施例4 ) 在霧除去裝置使用表示於第5圖之雙塔式活性碳吸附 裝置，施行與實施例1同樣之實驗。 吸附、再生塔係圓筒型而內徑爲2 0 0 m m，高度爲 1 0 0 0 m者。活性碳層之空間速度爲4 5 〇 h — 1。結果 ’洗滌丈合出口之S〇3濃度爲1 4 8 P P m者，而在吸附裝 置出口成爲3 3 ρ p m，除霧比率係7 8 %。試驗後置放 一天，拆卸排氣風扇並未被認出有腐蝕。 (發明之效果） 依據本發明，在處理P F C氣體中，可抑制設於分解 氣體洗淨塔之下游的排氣管或排氣風扇被腐鈾之情形。 (圖式之簡單說明） 第1圖係表示將本發明之P F C處理裝置設在半導體 鈾刻爐之例子的槪略圖。 第2圖係表示旋風式霧分離裝置者；第2 A圖係表示 俯視圖；第2 B圖係表示側面之剖視圖。 弟3圖係表不過濾式霧分離裝置剖視圖。 第4圖係表示使用於霧分離之電氣集塵裝置的槪略圖 〇 第5圖係表示使用於霧分離裝置之活性碳吸附裝置的 -----------裝-----：—訂--------- (請先閱讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） -16 - 478961 A7 _B7_ 五、發明說明（14 ) 槪略圖。 (記號之說明） 1 P F C分解塔 13 排氣洗滌塔 21 旋風式霧分離裝置 30 過濾式霧分離裝置 40 電氣集塵裝置 5 1 吸附、再生塔 (請先閱讀背面之注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐）Any method such as Mg (OH) 2 is not used for alkaline solids, and the method for decomposing gas is not provided. Among these, a spray type washing tower system is highly efficient, and it is preferable to prevent clogging caused by crystal precipitation or the like in the washing tower. The exhaust line from the scrubber tower is made of highly corrosion-resistant materials such as vinyl chloride or acrylic resin due to the flow of uranium-corrosive gas, or is coated on the inside of these materials Produced by the ideal. The same applies to the exhaust fan. (Example 1) The etching furnace 9 9, the charging tower 101, and the spray tower 102 were removed from the P F C processing apparatus in FIG. 1, and then the SF 6 process was performed. Adding nitrogen to SF6 dilutes the concentration of S F6 to about 5 0 0 P pm. Air 3 is added to the dilute gas, and the preheater 2 is heated. The water vapor system guides the exchanged water from the water to 3 to 3 times the theoretical amount and guides it into the preheater 2 to vaporize it. The thus adjusted reaction gas is led into a P F i C decomposition tower heated by the heater 6! L and in contact with the S F 6 decomposition catalyst and the S02 F 2 decomposition catalyst. In the SF 6 split catalyst, a catalyst composed of Ni 1 / t and A 1 2 03 is used, and in the S 2 2.F 2 decomposition catalyst, P d and La and A 1 2 03 are used. catalyst. The temperature of these catalysts is kept at 700 ~ 800 ° C. Space Velocity of Reactive Gas This paper size is in accordance with Chinese National Standard (CNS) A4 (210 X 297 mm) (Please read the note on the back? Matters before filling out this page) ---- Stupid • Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs -12 478961 κι Β7 V. Description of the invention (10) (Please read the precautions on the back before filling this page) As 1 0 0 〇h-1 . The gas system discharged from the exhaust scrubbing tower is guided to a cyclonic mist separation device 21 with an inner diameter (maximum diameter portion) of 24 mm and a height of 1 1 imm under the condition of an inlet speed of about 20 m / s ec. In the cyclone-type mist separation device, the builders shown in Figs. 2A and 2B are used. The inner diameter of the liquid discharge port 24 is 14 mm. The blades of the exhaust fan are coated with epoxy-based corrosion-resistant materials. The S 0 3 concentration in the gas before and after the cyclone-type mist separation device was measured, and the defogging ratio was calculated. The S 0 3 concentration is a value obtained by subtracting the SO 2 concentration measured by a gas chromatography analyzer from the SO X concentration measured by a liquid trapping method. As a result, a person with a concentration of S03 in front of the mist separation device of 153 P pm passed through the mist separation device became 30 p pm, and 80% of the mist was removed. After the test was placed for one day, the exhaust fan 16 was removed and no corrosion was recognized. The catalyst preparation method for the test is as follows. Boxing A 1 2 03 catalyst containing Ni: Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, dried commercially available boelhmite powder at 120 ° C for one hour. A solution of 2 1 0 · 8 2 g of water in which nickel nitrate 6 was dissolved was added to 2 0 g of the dry powder, and mixed. After mixing, dry at 250 to 300 ° C for about two hours, and fire at 700 ° C for two hours. The fired product was pulverized and sieved to have a particle size of 0.5 to 1 mm. The catalyst composition after completion is A 1: N i = 80: 20 (mol%) 〇 This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 public love) 478961 A7 B7 V. Description of the invention () Al2O3 catalyst containing Pd and La: A commercially available granular A 1 2 0 3 (manufactured by Sumitomo Chemical Co., Ltd., NKHD-24) was crushed into 0 · 5 ~ 1 mm in 1 Dry-dry at 20 ° C for one hour. After that, the lanthanum nitrate 6 was dissolved in water and the solution was impregnated into a solution of La 203 with a weight of 10 wt%. In other words, ′, lanthanum nitrate 6 and 2 6 · 84 g were dissolved in pure water and impregnated with A 1 2 03 1 0 g, and then dried at 120 ° C. for two hours and calcined. Let this be A 1 203 containing La. After firing, A 1 203 containing La was impregnated with a palladium nitrate solution so that the weight of P d became 0.5 wt%. Specifically, 100 g 'of Al203 containing La was dissolved in pure water in an amount of 4 · 4 3 9 w t% palladium nitrate solution 1 · 2 6 g and impregnated. After impregnation, drying was performed at 120 ° C for two hours and firing was performed. (Comparative example) In Example 1, the same experiment was performed in a state other than the application of a fan without using a mist separation device. As a result, there was fog in the fan, and acid water in which S 0 3 was dissolved was stored in the suction and exhaust ports. After the test was completed for one day, corrosion products were generated in the wind, and the gas flow path was blocked. In addition, corrosion products are fixed so that the fan cannot be started. (Embodiment 2) In Embodiment 1, the same experiment was performed using the filter type shown in Fig. 3 in the mist separation device. Filter-type mist separation device is the inner diameter of the cylinder. The paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) (Please read the precautions on the back before filling this page). --Order ---- Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 478961 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 B7 V. Description of the invention (12) 7 9mm, cylindrical shape with a height of 500 mm At the center of it (height of 250 mm), set the flange and set the filter 3 2, 3 3. The filter used is a commercially available glass, and two filter sheets 3 2 with a pore diameter of 100 to 160 are overlapped with a filter sheet 3 with a pore diameter of 160 to 2 5 0 // m. The thickness of the filter sheet is 2 mm in total. The gas velocity of the filter section is 24 cm / s e c. As a result, if the concentration of SO before entering the mist separation device was 138 p p m, the concentration of SO after passing the mist separation device was 16 p p m, and the ffii defogging ratio was 88%. After the test was placed for one day, the exhaust fan was removed and no corrosion was recognized. (Example 3) The same experiment as in Example 1 was performed using the electric dust collection device having the structure shown in Fig. 4 for the mist removing device. The electric dust collector is a tubular SUS dust collector with an inner diameter of 35 mm and a length of 110 mm in a cylinder made of vinyl chloride with an inner diameter of 45 mm. A tungsten discharge electrode with a diameter of 0.18 m was set at the center of the cylinder. The discharge electrode system is supported by a S U S discharge electrode support rod with a diameter of 3 mm. A direct-current high-voltage power supply (10 kV, 1000 / A) was connected to the discharge electrode and the collector. Using a voltage of 8 kV as the result of the decomposition treatment of s F 6 in the same manner as in Example 1v, a S03 concentration at the outlet of the washing tower of 140 ppm was 4 2 ppm at the outlet of the electric dust collector, and The division ratio is 70%. The test was stupid for one day, and the exhaust fan was not found to be rotten when disassembled. The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297). ----------! Pack -----: ---- Order · ----- II (Please read the notes on the back before filling out this page) 478961 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 B7 V. Invention Description ( 13) Eclipse. (Example 4) A double-tower activated carbon adsorption device shown in Fig. 5 was used for the mist removing device, and the same experiment as in Example 1 was performed. The adsorption and regeneration tower is cylindrical, with an inner diameter of 200 m m and a height of 100 m. The space velocity of the activated carbon layer is 450 h-1. Results When the concentration of S03 at the outlet of the washing was 148 P P m, it was 3 3 ρ p m at the outlet of the adsorption device, and the defogging ratio was 78%. After one day of testing, the exhaust fan was removed and no corrosion was recognized. (Effects of the Invention) According to the present invention, in the treatment of P F C gas, it is possible to suppress the situation where the exhaust pipe or the exhaust fan provided downstream of the decomposition gas cleaning tower is degraded by uranium. (Brief description of the drawings) Fig. 1 is a schematic diagram showing an example in which the P F C processing apparatus of the present invention is installed in a semiconductor uranium engraving furnace. Fig. 2 shows a cyclone-type mist separation device; Fig. 2 A shows a top view; and Fig. 2 B shows a side sectional view. Figure 3 is a sectional view of a filter mist separation device. Fig. 4 is a schematic diagram showing an electric dust collection device used for mist separation. Fig. 5 is a diagram showing an activated carbon adsorption device used for the mist separation device. -： — Order --------- (Please read the notes on the back before filling this page) This paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) -16-478961 A7 _B7_ 5. Description of the invention (14) 槪 Sketch. (Explanation of symbols) 1 PFC decomposition tower 13 Exhaust washing tower 21 Cyclone mist separation device 30 Filter mist separation device 40 Electric dust collection device 5 1 Adsorption and regeneration tower Printed by the Consumers' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, the paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm)