200536624 九、發明說明： 【發明所屬之技術領域】 本發明係關於一種循環式氣體溶解水供給裝置及該裝 置之運轉方法。更詳細言之，本發明係關於一種循環式氣 體溶解水供給裝置及該裝置之運轉方法，在將電子材料等 之濕洗淨工程中使用之特定氣體溶解，而提高洗淨效果的 氣體溶解水供給裝置中，使洗淨機未使用之氣體溶解水返 回到水槽，將溶存於氣體溶解水之特定氣體的濃度，維持 在一定値以上，且可將貯存氣體溶解水的水槽之上部空間 的特定氣體之濃度保持很低。 【先前技術】 將微粒子、有機物、金屬等從半導體用矽基板、液晶用 玻璃基板、光罩用石英基板等之電子材料之表面上除去， 在確保製品之品質、生產良率上極爲重要。濕洗淨工程之 洗劑中可使用的高純度純水或超純水中，已知溶解有氫、 臭氧等特定氣體的洗淨水，有發揮與溶解有數％等級之藥品 的洗淨液匹敵之洗淨效果之情形。除了具有強氧化力，對 除去有機物或一部分金屬污染有效的含臭氧水之外，將溶 解有高濃度氫氣之含氫水，做爲微粒子除去用之洗淨水已 受到注目。本發明人等提案有將由溶存氫氣濃度爲0.7mg/L 以上、飽和濃度以下，pH値爲6〜1 2之超純水所形成之電 子材料洗淨水，當作可將被微粒子所污染的半導體用矽基 板、液晶用玻璃基板等之電子材料，以使用的藥劑量少， 且效率好之高污染物除去率洗淨之電子材料洗淨水。（日本 專利文獻1) 200536624 先前技術之氣體溶解水供給裝置，爲了維持溶存氣體濃 度，一般爲一遍式的供給，即使在使用點不使用氣體溶解 水，亦將一定量的氣體溶解水進行通水而放出，但是爲了 節省氣體溶解水之消耗量，利用將氣體溶解水循環供給， 而嘗試將浪費的放出消除。 例如，提案有：一種裝置，其係含氫超純水供給裝置， 用於使洗淨用之含有氫的超純水，不產生剩餘而廢棄，即 使使用水量變動之時，亦可將含有穩定之溶存氫氣濃度的 φ 氫超純水供給到使用點，且具有將超純水之溶存氣體除去 之脫氣部、將氫氣溶解於脫氣後之超純水中之溶解部、用 於保持使用點之未使用的剩餘含氫超純水與被補給之含氫 超純水的混合水之密閉式水槽，而可對應於水位之變動而 將氫氣補給到密閉式之水槽的氣相部中，將含氫超純水藉 由送水泵經由過濾器而送到使用點，將未使用之含氫超純 水循環而返回水槽（日本專利文獻2)。但是，該裝置係於水 槽之上部空間充滿氫氣之故，在確保安全方面不夠充分。 φ 並且提案有一種氣體溶解水供給裝置，其係將使用於電 子材料等之濕洗淨的氣體溶解水供給到使用點，將使用點 未使用之剩餘的氣體溶解水送回貯存槽，氣體溶解水之氣 體濃度不會產生變動，而可循環使用氣體溶解水者，在用 於返送使用點未使用的剩餘之氣體溶解水的貯存槽中，設 置有遮蔽材，接觸於氣體溶解水之液面而上下移動且切斷 氣體溶解水與氣相（日本專利文獻3)。雖然該裝置有用且安 全’但是需要使用特殊的構件之故，實用上有其難點。 〔專利文獻1〕日本特開平1 1 -29794號公報（第2頁） • 200536624 〔專利文獻2〕日本特開平1 1 -7702 1號公報（第2頁、第 3圖） 〔專利文獻3〕日本特開2000-27 1 549號公報（第2頁、第 1圖、第2圖） 〔發明欲解決的課題〕 本發明之目的在提供一種循環式氣體溶解水供給裝置及 該裝置之運轉方法，在將電子材料等之濕洗淨工程中使用 的特定之氣體溶解，而提高洗淨效果的氣體溶解水供給裝 φ 置中，使洗淨機未使用之氣體溶解水返回到水槽中，將溶 存於氣體溶解水之特定氣體的濃度，維持在一定値以上， 且將貯存氣體溶解水的水槽之上部空間之特定氣體的濃度 保持很低。 【發明內容】 〔解決課題之手段〕 本發明人等，在反覆地進行解決上述課題之銳意硏究後 之結果，設置水槽以用於保持使用點未使用的氣體溶解 0 水’與補給已使用之氣體溶解水而供給的氣體溶解水之混 合水’藉由將水槽之水位保持在一定以補給需要量的氣體 溶解水，且藉由將補給的氣體溶解水做成一定量以上，可 使溶存之特定氣體的濃度維持在一定値以上，進而，發現 即使溶存於水中之特定氣體揮發成氣相時，亦可藉由將氮 氣、稀有氣體等之惰性氣體以一定流量以上進行通氣，而 可將氣相中之特定氣體濃度抑制在一定値以下，基於此見 解而終於完成本發明。 即’本發明係提供： 200536624 (1) 一種循環式氣體溶解水供給裝置，其係氣體溶解水 供給裝置，具有製造特定之氣體溶解水的溶解裝置A、貯 存特定之氣體溶解水的水槽B、連接溶解裝置a與水槽B 之連接配管C、將水槽B之貯存水送出到洗淨機之泵D、 從水槽B經過泵D與到洗淨機之分歧點而返回水槽b之循 環配管E、將氣體供給到水槽B之上部空間中之氣體配管F 者，且其特徵爲連接配管C之下端及循環配管E之下端係 沒入於水槽B內之水面下。 (2) 如（1)所記載之循環式氣體溶解水供給裝置，其中係 通過氣體配管F而供給惰性氣體。 (3) 如（2)所記載之循環式氣體溶解水供給裝置，其中惰 性氣體係氮氣。 (4) 如（1)所記載之循環式氣體溶解水供給裝置，其中特 定之氣體係氫氣。 (5) 如（4)所記載之循環式氣體溶解水供給裝置，其中具 有監視水槽B之上部空間的氧氣檢測器或氧氣濃度計。 (6) 一種循環式氣體溶解水供給裝置之運轉方法，該循 環式氣體溶解水供給裝置係具有製造特定之氣體溶解水的 溶解裝置A、貯存特定之氣體溶解水之水槽B、連接溶解 裝置A與水槽B之連接配管C、將水槽B之貯存水送出到 洗淨機之泵D、從水槽B經過泵D與通向洗淨機之分歧點 而返回水槽B之循環配管E、將氣體供給到水槽B之上部 空間之氣體配管F，且在分歧點中將特定的氣體溶解水供 給到洗淨機，並使剩餘的特定之氣體溶解水循環而返回水 槽B，連接配管C之下端及循環配管E之下端係沒入於水 200536624 槽B內之水面下者，且其特徵爲相對於藉由泵D送出之氣 體溶解水1 0 0體積份，將從溶解裝置A對水槽B補給的氣 體溶解水之量，做成5體積份以上。 (7) 如（6)所記載之循環式氣體溶解水供給裝置之運轉 方法，其中特定之氣體係氫氣，從溶解裝置A對水槽B補 給之氣體溶解水的溶存氫氣濃度係做成0.6mg/L以上。 (8) 如（7)所記載之循環式氣體溶解水供給裝置之運轉 方法，其中藉由將通過氣體配管F供給的氣體之流量，相 對於水槽B之氣液接觸面積而做成〇.1 5〜50L(標準狀 態）/min · m2，而使水槽B之上部空間中之氫氣濃度保持在 4.0體積％以下。 (9) 如（7)或（8)所記載之循環式氣體溶解水供給裝置之 運轉方法，其中從水槽B供給的氫氣溶解水之溶存氫氣濃 度，係做成〇.6mg/L以上。 (10) 如（6)所記載之循環式氣體溶解水供給裝置之運轉 方法，其中係將水槽B液面之高度的變動，保持於標準水 位之60%以下。 〔發明之效果〕 藉由使用本發明之循環式氣體溶解水供給裝置及該裝置 之運轉方法，可將特定之氣體溶解水之溶存氣體濃度維持 在一定値以上，且可將水槽之上部空間之特定的氣體濃度 抑制在一定値以下，且循環供給特定之氣體溶解水。 【實施方式】 本發明之循環式氣體溶解水供給裝置’係氣體溶解水供 給裝置，具有製造特定之氣體溶解水的溶解裝置A、貯存 -10 - *200536624 特定之氣體溶解水之水槽B、連接溶解裝置A與水槽B之 連接配管C、將水槽B之貯存水送出到洗淨機之栗D、從 水槽B經過泵〇與通向洗淨機之分歧點而返回水槽B之循 環配管E、將氣體供給到水槽B之上部空間之氣體配管F ’ 且連接配管C之下端及循環配管E之下端，係沒入於水槽 B內之水面下。 可適用本發明裝置或本發明方法的特定氣體’可舉出例 如氬氣、臭氧氣體、氧氣、氬氣、二氧化碳氣體、氣氣。 φ 本發明在該等中，特別可適用於氫氣溶解水。 第1圖係本發明裝置之一個態樣之工程系統圖。本態樣 之裝置係具有製造特定之氣體溶解水的溶解裝置A、貯存 特定之氣體溶解水之水槽B、連接溶解裝置A與水槽B之 連接配管C、將水槽B之貯存水送出到洗淨機之泵D、從 水槽B經過泵D與通向洗淨機之分歧點而返回水槽B之循 環配管E、將氣體供給到水槽B之上部空間之氣體配管F。 超純水經由閥1而被送到溶解裝置A，將特定氣體溶解而 | 形成氣體溶解水。在水槽B設置有液面計2，藉由從液面 計送出之信號而控制閥3之開度，將水槽B內的水位保持 在一定。貯存於水槽B內之氣體溶解水，係由泵D送出’ 藉由熱交換器4加溫或冷卻成一定之溫度，藉由設置於泵 之二次側的純化機構5而將微粒子等除去，並由氣體濃度 計6測定氣體溶解水之特定氣體濃度。氣體溶解水在循環 配管E之分歧點7、8分流，經由閥9、10送到洗淨機，而 使用於電子材料等之洗淨。洗淨中未使用的剩餘之氣體溶 解水’係經由循環配管E而返回水槽B。在循環配管E設 -11 - •200536624 置有用於將使用點之水壓保持在一定的閥11。 在水槽B，設置有將氣體供給到水槽B之上部空間的氣 體配管F，藉由從氣體配管F供給的氣體，將水槽B之上 部空間的特定氣體予以稀釋，而將上部空間之特定氣體濃 度保持於一定値以下。在水槽B之上部空間，設置有監視 上部空間之特定氣體濃度之特定氣體監視器1 2、監視上部 空間之氧氣濃度的氧氣監視器1 3、將上部空間保持於正壓 用之壓力調整器14。 φ 在本發明之循環式氣體溶解水供給裝置中’連接配管C 之下端1 5及循環配管E之下端1 6，係沒入於水槽B內之 水面下。藉由連接配管C的下端1 5及循環配管E的下端 1 6，係沒入於水槽B內的水面下之方式，從連接配管C補 給到水槽B的特定氣體溶解水，和從循環配管E返回水槽 B之特定氣體溶解水，不會與上部空間之氣相接觸’而可 防止特定氣體從氣體溶解水揮發，而降低氣體溶解水之特 定氣體濃度，並防止上部空間之特定氣體濃度上昇。 ^ 在本發明裝置中，通過氣體配管F供給惰性氣體較佳。 溶解於水中的特定氣體，若爲氫氣、臭氧氣體等具有危險 性的氣體之時，藉由通過氣體配管F將惰性氣體供給到水 槽B之上部空間，可降低上部空間之特定氣體濃度，而提 高裝置之安全性。供給的惰性氣體並無特別限制，例如， 可舉出爲氮氣、稀有氣體等。在該等之中，以使用氮氣較 佳。 本發明裝置可較適於當作以氫氣做爲特定氣體之循環式 氫氣溶解水供給裝置而使用。氫氣溶解水係使用於電子材 -12- 200536624 料等之洗淨，發揮將附著的微粒子除去之優異效果。但是’ 將氫氣溶解水貯存於水槽B時’水槽B之上部空間變成氫 氣濃度高的狀態。在常溫常壓下’氫氣與空氣之混合氣體 的爆炸下界限爲氫氣4 · 1體積％，因此水槽B之上部空間變 成氣氣濃度較高之狀態時’會變成極度危險。本發明裝置 做爲循環式氫氣溶解水供給裝置而使用’亦可將水槽B之 上部空間之氫氣濃度保持較低，因而可保持安全地將氫氣 溶解水供給到洗淨機。 φ 本發明裝置中，在特定之氣體爲氫氣之時’設置監視水 槽B之上部空間的氧氣檢測器或氧氣濃度計較佳。由於意 外之事故等，而使水槽B之上部空間之氫氣濃度超過4體 積％，因而即使該處有著火源之時，若沒有氧氣存在的話亦 不會產生爆炸。本發明裝置中，水槽B內藉由壓力調整器 1 4而經常地被保持於正壓之故，因此不會有氧氣從外氣向 水槽B之混入，故通常水槽B之上部空間之氧氣濃度爲0 體積％。但是，即使將惰性氣體供給到水槽B之上部空間， φ 萬一空氣侵入之時，仍會招致危險的狀態，因此藉由設置 氧氣檢測器或氧氣濃度計，而監視水槽B之上部空間，更 可提高安全性。 本發明之循環式氣體溶解水供給裝置，可做成與第1圖 所示之態樣相異的態樣。例如，將閥1及閥3之中的任何 一個省略，將信號從液面計2送到剩下的閥而控制開度， 可使水槽B內之水位保持於一定。並且，氣體濃度計6係 用於測定循環配管E及水槽B之內部的氣體溶解水之溶存 氣體濃度者，在循環配管E之任何位置均可，可用氣體濃 -13- 200536624 度計直接測定水槽B內之氣體溶解水的溶存氣體濃度。再 者，監視上部空間的特定氣體濃度之特定氣體監視器1 2， 及監視上部空間之氧氣濃度的氧氣監視器1 3之排氣，亦可 排出到系統外。 在本發明之循環式氣體溶解水供給裝置之運轉方法之 中，循環式氣體溶解水供給裝置係具有製造特定之氣體溶 解水的溶解裝置A、貯存特定之氣體溶解水之水槽B、連 接溶解裝置A與水槽B之連接配管C、將水槽B之貯存水 φ 送出到洗淨機之泵D、從水槽B經過泵D與通向洗淨機之 分歧點而返回水槽B之循環配管E、將氣體供給到水槽B 之上部空間之氣體配管F，且在分歧點中將特定的氣體溶 解水供給到洗淨機，使剩餘的特定之氣體溶解水循環而返 回水槽B，連接配管C之下端及循環配管E之下端係沒入 於水槽B內之水面下，且相對於循環水1 0 0體積份’將從 溶解裝置A對水槽B補給的氣體溶解水之量，做成爲5體 積份以上。 本發明裝置中，在循環配管循環的氣體溶解水係在分歧 ® 點分流，在洗淨機中使用於洗淨後，返回水槽B之氣體溶 解水的量減少，水槽B內之氣體溶解水的量開始減少。此 時，由液面計2檢測到液面的降低’將信號送到閥3而將 閥的開度變大，使氣體溶解水從溶解裝置A補給到水槽B ’ 而使液面之高度成爲一定。在本發明方法中，水槽B液面 之高度的變動爲標準水位之6 0 %以下較佳’在4 0 %以下更 佳，2 0 %以下進而更佳。水槽之液面高度的變動超過標準水 位的60%之時，會使連接配管C之下端、循環配管E之下 -14- 200536624 端難以沒入於水面下，並且水槽B之上部空間之氣相的組 成變動，因而本發明裝置恐有難以穩定地運轉之虞。通常’ 藉由液面計2而設定上限水位、下限水位，並控制來自於 連接配管C之補給水量，以使液面高度形成在該範圍內° 在本發明方法中，相對於藉由泵D送出之氣體溶解水1 〇〇 體積份，在洗淨機中使用5體積份以上的氣體溶解時’藉 由將與使用於洗淨之量相等的氣體溶解水從溶解裝置A補 給到水槽B的方式，可使氣體溶解水之溶存氣體濃度保持 φ 於預定之値。但是，相對於藉由泵D送出之氣體溶解水1 〇〇 體積份，在洗淨機中使用的氣體溶解水之量，爲未滿5體 積份之時，相對於藉由泵D送出之氣體溶解水100體積份’ 將從溶解裝置A補給到水槽B的氣體溶解水之量，做成爲 5體積份以上。此時，將來自水槽B或循環配管E之氣體 溶解水的一部分放出，而使水槽B之液面高度形成一定較 佳。因此，在水槽B·或循環配管E之任意位置上預先設置 放出配管即可。從溶解裝置A補給到水槽B的氣體溶解水 $ 之量，相對於藉由泵D送出之氣體溶解水1 〇〇體積份而爲 未滿5體積份之時，氣體溶解水之溶存氣體濃度會有降低 之虞。 在本發明方法中，特定之氣體爲氫氣之時，從溶解裝置A 補給到水槽B的氫氣溶解水之溶存氫氣濃度’係做成 0.6mg/L以上較佳，做成i.〇mg/L以上更佳。使用氫氣溶解 水將附著於電子材料等之微粒子洗淨之時，溶存氫氣濃度 爲0.6mg/L以上時，可發現良好的洗淨效果。並且，藉由 將從溶解裝置A補給到水槽B的氫氣溶解水之溶存氫氣濃 -15- 200536624 度做成1.0mg/L以上，可以將從水槽B藉由泵D向循環配 管E送出，且在洗淨機中使用的氫氣溶解水之溶存氫氣濃 度，容易地保持在0.6mg/L以上。 在本發明方法中，特定之氣體爲氫氣之時，係藉由將通 過氣體配管F供給的氣體之流量，相對於水槽B之氣液接 觸面積而做成0.15〜5014標準狀態）/1^11.1112，而將水槽8 之上部空間之氫氣濃度保持在4.0體積％以下較佳。通過氣 體配管F供給的氣體之流量，相對於水槽B之氣液接觸面 ^ 積爲未滿〇 · 1 5 L (標準狀態）/ m i η · m2時，會有水槽B之上部 空間之氫氣濃度超過4.0體積％之虞。在常溫常壓下，氫氣 與空氣之混合氣體的爆炸下界限爲氫氣4 · 1體積％，因此藉 由將水槽B之上部空間的氫氣濃度做成4,0體積％以下，不 僅可防止水槽B內部之爆炸事故，即使水槽b之上部空間 的氣體洩露到大氣中之時，亦可消除爆炸事故之可能性。 若通過氣體配管F供給的氣體之流量，相對於水槽b之氣 液接觸面積爲超過50L(標準狀態）/min· m2之時，氫氣從氫 φ 氣溶解水向水槽B之上部空間的氣相之揮發量變多，因而 有氫氣溶解水之溶存氫氣濃度降低之虞。通過氣體配管F 供給到水槽B之上部空間的的氣體，可經由壓力調整器！ 4 而排出。 〔實施例〕 以下，雖然將舉實施例而更詳細地說明本發明，但是本 發明並不由該等實施例而做任何的限定。 在實施例及比較例中，使用第2圖所示的氣體溶解水供 給裝置，而進行氫氣溶解水之循環試驗。該裝置係具備有： -16- 200536624 具備聚丙烯製之氣體透過膜之氫氣溶解裝置a、氣液接觸 面積〇·25 m2而容積爲200L之水槽b、連接溶解裝置a及水 槽b的連接配管c、將水槽b之水位變動調整成6.4cm以下 之閥3、將氫氣溶解水從水槽b送出到循環配管e的泵d、 將氫氣溶解水的溫度保持於25 t用之熱交換器4、過濾器 5、溶存氫氣濃度計6、放出水排出閥9、將循環配管e內 的壓力保持於0.2MPa之閥11、將氮氣供給到水槽b之上部 空間之氣體配管f、在供給氣體之出口側將水槽b之上部空 φ 間保持於正壓用之壓力調整器1 4、測定水槽b之上部空間 的氫氣濃度之感測器1 2。連接配管c之下端1 5及循環配管 e之下端1 6，係位於從水槽之底部離開1 0cm上方的位置。 實施例1 在溶解裝置a調製溶存氫氣濃度1.0mg/L之氫氣溶解水， 將氫氣溶解水1 60L倒入水槽b內，將氫氣溶解水充滿循環 配管e。 將溶存氫氣濃度l.〇mg/L之氫氣溶解水l.OL/min，從溶解 φ 裝置a供給到水槽b，將氫氣溶解水20L/min藉由泵d從水 槽b向循環配管e送出，並從放出水排出閥9將放出水 l.OL/nnn排出，使氫氣溶解水循環。並且，從氣體配管f 將氮氣0.5 L(標準狀態）/min供給到水槽b之上部空間。 使用溶存氫氣濃度計6測定的氫氣溶解水之溶存氫氣濃 度，在運轉開始時爲l.〇mg/L、1小時後爲0.88mg/L、2小 時後爲0.75 mg/L、3小時後爲0.68 mg/L、4小時後爲0.66 mg/L、5小時後爲0,65 mg/L、6小時後爲0.65 mg/L。水槽 b之上部空間的氫氣濃度，做成從運轉開始時到1 8小時後 -17- 200536624 一直爲0.0體積％。 比較例1 除了將溶存氫氣濃度1 . 〇 m g / L之氣氣溶解水〇 · 5 L / m i η從 溶解裝置a供給到水槽b，並從放出水排出閥9將放出水 0.5L/nnn排出之外，與實施例1相同地，將氫氣溶解水 2 0L/min藉由泵d從水槽b向循環配管e送出，使氫氣溶解 水循環。 使用溶存氫氣濃度計6測定的氫氣溶解水之溶存氫氣濃 g 度，在運轉開始時爲l.Omg/L、1小時後爲0.85mg/L、2小 時後爲0.73 mg/L、3小時後爲0.65 mg/L、4小時後爲 0.57mg/L、5 小時後爲 〇·53 mg/L、6 小時後爲 0.49 mg/L ° 比較例2 除了不進行從溶解裝置a到水槽b之氫氣溶解水的供 給，及從放出水排出閥9將放出水排出之外，與實施例1 相同地，將氫氣溶解水20L/min藉由泵d從水槽b向循環 配管e送出，而使氫氣溶解水循環。 使用溶存氫氣濃度計6測定的氫氣溶解水之溶存S氣？農 ® 度，在運轉開始時爲l.〇mg/L、1小時後爲0.83mg/L、2小 時後爲0.6 9 m g / L、3小時後爲0.4 9 m g / L、4小時後爲 0.35mg/L、5 小時後爲 0.25 mg/L、6 小時後爲 〇·21 mg/L ° 實施例2 除了將從氣體配管f供給到水槽b之上部空間的氮氣之 量做成0.03 75 L(標準狀態）/min以外，與實施例1相同地’ 將溶存氫氣濃度l.Omg/L之氫氣溶解水l.OL/min從溶解裝 置a供給到水槽b，將氫氣溶解水20 L/min藉由泵d從水 -18- 200536624 槽b向循環配管e送出，並從放出水排出閥9將放出水 1 .OL/min排出，而使氫氣溶解水循環。 使用溶存氫氣濃度感測器6測定的氫氣溶解水之溶存氫 氣濃度，在運轉開始時爲1.0mS/L、1小時後爲0.88mg/L、 2小時後爲0.75 mg/L、3小時後爲〇·68 mg/L、4小時後爲 0.66 mg/L、5 小時後爲 0.65 mg/L、6 小時後爲 0.65 mg/L。 以氫氣濃度感測器1 2測定的水槽b之上部空間的氫氣濃 度，在運轉開始時爲〇 · 5 3體積％、2小時後爲1 · 4 8體積％、 4小時後爲2.5 2體積％、6小時後爲3 . 1 3體積％、8小時後 爲3 . 3 9體積％、1 0小時後爲3 · 5 6體積％、1 2小時後爲3 · 5 9 體積％、1 4小時後、1 6小時後、1 8小時後均爲3 · 6 4體積％。 比較例3 除了未從氣體配管f將氮氣供給到水槽b之上部空間以 外，與實施例1相同地’將溶存氫氣濃度1 · 〇 m g /L之氫氣 溶解水1. 〇L/min從溶解裝置a供給到水槽b，將氫氣溶解 水2OL/min藉由泵d從水槽b向循環配管e送出，並從放 出水排出閥9將放出水丨.OL/min排出，使氫氣溶解水循環。 以氫氣濃度感測器1 2測定的水槽b之上部空間的氫氣濃 度，在運轉開始時爲〇 · 5 3體積％、2小時後爲1 · 7 7體積％、 4小時後爲2.79體積％、6小時後爲3.49體積％、8小時後 爲3.73體積％、1〇小時後爲3.88體積％、12小時後爲3.98 體積％、1 4小時後爲4.0 2體積％、1 6小時後爲4.0 7體積％、 1 8小時後爲4. 1 〇體積％。 將實施例1〜2及比較例1〜3之運轉條件顯示於第1表中’ 將氫氣溶解水之溶存氫氣濃度的隨時間變化顯示於第3圖 -19- 200536624 中，將水槽b之上部空間的氫氣濃度的隨時間變化顯不於 第4圖中。 【第1表】 氫氣溶解水補 相對於送出水100體積 氮氣流量 給量(L/min) 份之補給水(體積份） (L/min · m2) 實施例1 1.0 5 2.0 比較例1 0.5 2.5 2.0 比較例2 0 0 2.0 實施例2 1.0 5 0.15 比較例3 1.0 5 0 如第3圖中可看出，相對於從水槽b藉由泵d送出到循 環配管e之氫氣溶解水1 〇 〇體積份’在從溶解裝置a補給 氫氣溶解水5體積份之實施例1中’從水槽b送出的氫氣 溶解水之溶存氫氣濃度’爲了做爲微粒子除去之用的洗淨 水，而必需保持〇.6mg/L以上。相對於此’相對於從水槽b 藉由泵d送出到循環配管e之氫氣溶解水1 〇 〇體積份’在 ^ 從溶解裝置a補給氫氣溶解水2 · 5體積份之比較例1中’ 從水槽b送出的氣氣溶解水之溶存氫氣濃度’係降低到 0.6mg/L以下。在沒有從溶解裝置a對水槽b補給氫氣溶解 水的比較例2中，從水槽b送出的氫氣溶解水之溶存氫氣 濃度會急速地降低。 由此結果可了解，將從氫氣溶解裝置a補給到水槽b之 氫氣溶解水之溶存氫氣濃度做成1 .Omg/L，將氫氣溶解水之 補給量，相對於從水槽b藉由泵d送出到循環配管e之水 量1 0 0體積份，而做成5體積份以上時，可使送出到循環 -20- 200536624 配管e之氫氣溶解水之溶存氫氣濃度’保持在做爲洗淨水 發揮充分的性能之0.6mg/L以上。 如第4圖可看出，相對於水槽b之上部空間的水槽b之 氣液接觸面積，在通過氣體配管f供給2 · 0 L (標準狀 態）/min · m2之氮氣之實施例1之中’水槽b之上部空間的 氫氣濃度爲0體積％，而在通過氣體配管f供給0.15L(標準 狀態）/ m i η · m2之氮氣的貫施例2之中’水槽b之上部空間 的氮氣濃度爲3.6 4體積％而穩定。相對於此’在未供給氮 氣到水槽b之上部空間之比較例3之中’在1 8小時後水槽 b之上部空間的氫氣濃度，達到氫氣與空氣的混合氣體之 爆炸下界限的4. 1體積％，並有稍微上昇之傾向。 從此結果可了解，藉由相對於水槽b之氣液接觸面積’ 而通過氣體配管f將0.15L(標準狀態）/min · m2以上之氮氣 供給到水槽b之上部空間，可使水槽b之上部空間的氫氣 濃度保持於4.0體積％以下。 〔產業上利用之可行性〕 依照本發明之循環式氣體溶解水供給裝置及該裝置的運 轉方法，使用溶解有電子材料等之濕洗淨工程中使用的特 定之氣體之氣體溶解洗淨水，可使在洗淨機未使用之氣體 溶解洗淨水返回到水槽，而且將溶存在氣體溶解洗淨水之 特定氣體濃度，維持在一定値以上，並且，可將貯存氣體 溶解洗淨水的水槽之上部空間之特定氣體的濃度保持較 低。本發明裝置及方法係適用於氫氣溶解水，使溶存氫氣 濃度維持較高而發揮充分的洗淨效果，且將貯存氫氣溶解 水的水槽之上部空間之氫氣濃度保持較低，因此可安全地 利用氫氣溶解水而進行電子材料等之洗淨。 -21- 200536624 【圖式簡單說明】 第1圖係本發明裝置之一個形態之工程系統圖。 第2圖係在實施例中使用的裝置之說明圖。 第3圖係顯示氫氣溶解水之溶存氫氣濃度之隨時間變化 的曲線圖。 第4圖係顯示水槽之上部空間的氫氣濃度之隨時間變化 的曲線圖。 【主要元件符號說明】 A、 a…溶解裝置 B、 b…水槽 C、 c…連接配管 D、 d…栗 E、 e…循環配管 F、 f…氣體配管 1、3、9、1 0、1 1 …閥 2…液面計 4…熱交換器 5…純化機構 ® 6…氣體濃度計 7、8…分歧點 12…特定氣體監視器 13…氧氣監視器 14···壓力調整器 15…連接配管之下端 16…循環配管之下端 -22-200536624 IX. Description of the invention: [Technical field to which the invention belongs] The present invention relates to a circulating gas dissolved water supply device and a method for operating the device. In more detail, the present invention relates to a circulating gas-dissolved water supply device and a method of operating the device, which is a gas-dissolved water that dissolves a specific gas used in a wet cleaning process of electronic materials and the like, and improves the cleaning effect. In the supply device, the gas-dissolved water not used in the washing machine is returned to the water tank, and the concentration of the specific gas dissolved in the gas-dissolved water is maintained at a certain level or more, and the specific space above the water tank that stores the gas-dissolved water can be specified. The gas concentration is kept low. [Prior art] Removing fine particles, organic substances, metals, etc. from the surface of electronic materials such as silicon substrates for semiconductors, glass substrates for liquid crystals, and quartz substrates for photomasks is extremely important in ensuring the quality of products and production yield. The high-purity pure water or ultrapure water that can be used in the lotion of the wet cleaning process is known to have dissolved water such as hydrogen, ozone and other specific gases. It is comparable to detergents that dissolve several percent of pharmaceuticals. The cleaning effect. In addition to ozone-containing water that has strong oxidizing power and is effective for removing organic matter or some metal pollution, hydrogen-containing water in which high-concentration hydrogen is dissolved has been attracted attention as washing water for fine particle removal. The present inventors have proposed washing electronic water made of ultrapure water having a dissolved hydrogen concentration of 0.7 mg / L or more and a saturation concentration or less, and a pH of 6 to 12 as the contaminated particles. Electronic materials, such as silicon substrates for semiconductors and glass substrates for liquid crystals, are cleaned with high-efficiency, high-contamination-removal rates of electronic materials. (Japanese Patent Document 1) 200536624 The gas-dissolved water supply device of the prior art is generally a one-time supply in order to maintain the dissolved gas concentration. Even if gas-dissolved water is not used at the point of use, a certain amount of gas-dissolved water is passed through. It is released, but in order to save the consumption of gas-dissolved water, it is tried to eliminate wasteful discharge by recycling the gas-dissolved water. For example, there are proposals for a device which is a hydrogen-containing ultrapure water supply device for making ultrapure water containing hydrogen for cleaning to be discarded without generating a surplus. Even when the amount of water used varies, the content can be stabilized. Φ hydrogen ultrapure water with dissolved hydrogen concentration is supplied to the use point, and it has a degassing part to remove the dissolved gas of ultrapure water, a dissolving part to dissolve hydrogen in degassed ultrapure water, and is used for maintaining use The closed water tank of the mixed water of the remaining unused hydrogen-containing ultrapure water and the replenished hydrogen-containing ultrapure water can be supplied to the gas phase of the closed water tank in accordance with the change of the water level. The hydrogen-containing ultrapure water is sent to a point of use by a water pump through a filter, and unused hydrogen-containing ultrapure water is circulated and returned to the water tank (Japanese Patent Document 2). However, because the space above the water tank is full of hydrogen, the device is not sufficient to ensure safety. φ Also proposed is a gas-dissolved water supply device that supplies wet-dissolved gas-dissolved water used in electronic materials to the point of use, and returns the remaining gas-dissolved water that is not used at the point of use to the storage tank to dissolve the gas The gas concentration of water does not change, and those who can reuse gas-dissolved water can use a shielding material in the storage tank for returning the remaining gas-dissolved water that is not used at the point of use, and contact the liquid level of the gas-dissolved water On the other hand, it moves up and down to cut off the gas-dissolved water and the gas phase (Japanese Patent Document 3). Although this device is useful and safe, it requires practical components because of the need to use special components. [Patent Document 1] Japanese Patent Application Laid-Open No. 1 1-29794 (Page 2) • 200536624 [Patent Document 2] Japanese Patent Application Laid-Open No. 1 1-7702 1 (Page 2, Figure 3) [Patent Literature 3] Japanese Patent Laid-Open No. 2000-27 1 549 (Page 2, Figure 1 and Figure 2) [Problems to be Solved by the Invention] The object of the present invention is to provide a circulating gas-dissolved water supply device and a method for operating the device. In the gas dissolving water supply device φ that dissolves a specific gas used in the wet cleaning process of electronic materials and the like, and improves the cleaning effect, the gas dissolving water not used by the washing machine is returned to the water tank, and the The concentration of the specific gas dissolved in the gas-dissolved water is maintained above a certain level, and the concentration of the specific gas in the space above the water tank in which the gas-dissolved water is stored is kept low. [Summary of the Problem] [Means for Solving the Problem] As a result of repeated efforts to solve the above-mentioned problems, the present inventors set up a water tank to keep the unused gas at the point of use dissolved in 0 water 'and replenishment has been used The mixed water of the gas-dissolved water supplied by the gas-dissolved water can be dissolved by keeping the water level of the water tank at a certain level to replenish the required amount of gas-dissolved water, and by making the replenished gas-dissolved water to a certain amount or more. The concentration of the specific gas is maintained at a certain level or more. Furthermore, it was found that even when the specific gas dissolved in water evaporates into a gas phase, it is possible to ventilate an inert gas such as nitrogen or a rare gas at a certain flow rate or more. Based on this knowledge, the specific gas concentration in the gas phase is suppressed below a certain threshold, and the present invention has finally been completed. That is, the present invention provides: 200536624 (1) A circulating gas-dissolved water supply device, which is a gas-dissolved water supply device, which has a dissolving device A for manufacturing specific gas-dissolved water, a water tank B for storing specific gas-dissolved water, The connection pipe C connecting the dissolving device a and the water tank B, the storage water of the water tank B is sent to the pump D of the washing machine, the circulation pipe E from the water tank B to the water tank b through the divergence between the pump D and the washing machine, Those who supply gas to the gas pipe F in the upper space of the water tank B are characterized in that the lower end of the connection pipe C and the lower end of the circulation pipe E are submerged below the water surface in the water tank B. (2) The circulating gas-dissolved water supply device according to (1), wherein an inert gas is supplied through a gas pipe F. (3) The circulating gas-dissolved water supply device according to (2), wherein the inert gas system is nitrogen. (4) The circulating gas-dissolved water supply device as described in (1), wherein the specific gas system is hydrogen. (5) The circulating gas-dissolved water supply device according to (4), which includes an oxygen detector or an oxygen concentration meter for monitoring the space above the water tank B. (6) A method for operating a circulating gas-dissolved water supply device. The circulating gas-dissolved water supply device has a dissolving device A for manufacturing specific gas-dissolved water, a water tank B for storing specific gas-dissolving water, and a dissolving device A. Connect pipe C to water tank B, send the stored water of water tank B to pump D of the washing machine, return from water tank B to circulation pipe E of water tank B through the divergence between pump D and the way to the washing machine, and supply gas Go to the gas piping F in the upper space of the water tank B, and supply specific gas-dissolved water to the washing machine at the branch point, and circulate the remaining specific gas dissolved water to return to the water tank B, and connect the lower end of the pipe C and the circulation pipe The lower end of E is submerged in the water surface of the water 200536624 tank B, and is characterized by dissolving 100 parts by volume of water dissolved by the gas sent by the pump D, and dissolving the gas supplied from the dissolving device A to the water tank B. The amount of water is 5 parts by volume or more. (7) The operating method of the circulating gas dissolved water supply device as described in (6), in which the hydrogen concentration of the specific gas system, the dissolved hydrogen concentration of the gas dissolved water supplied from the dissolution device A to the water tank B is 0.6 mg / L or more. (8) The operating method of the circulating gas-dissolved water supply device as described in (7), wherein the flow rate of the gas supplied through the gas pipe F is set to 0.1 with respect to the gas-liquid contact area of the water tank B. 5 to 50 L (standard state) / min · m2, so that the hydrogen concentration in the space above the water tank B is maintained at 4.0% by volume or less. (9) The operating method of the circulating gas-dissolved water supply device as described in (7) or (8), wherein the dissolved hydrogen concentration of the hydrogen-dissolved water supplied from the water tank B is made to be 0.6 mg / L or more. (10) The operation method of the circulating gas-dissolved water supply device as described in (6), wherein the fluctuation of the height of the liquid surface of the water tank B is kept below 60% of the standard water level. [Effect of the Invention] By using the circulating gas-dissolved water supply device of the present invention and the operation method of the device, the dissolved gas concentration of specific gas-dissolved water can be maintained at a certain level or more, and the space above the water tank can be maintained. The specific gas concentration is suppressed below a certain level, and the specific gas dissolved water is circulated and supplied. [Embodiment] The circulating gas-dissolved water supply device of the present invention is a gas-dissolved water supply device, which has a dissolving device A for manufacturing specific gas-dissolved water, a storage tank -10-* 200536624, a specific gas-dissolved water tank B, and connection The piping C connecting the dissolving device A and the water tank B, the storage water of the water tank B is sent to the pump D of the washing machine, the water pipe B passes through the pump 0 and the point of divergence to the washing machine, and the return pipe E is returned to the water tank B. The gas piping F 'that supplies gas to the upper space of the water tank B and connects the lower end of the piping C and the lower end of the circulation piping E is submerged under the water surface in the water tank B. Specific gases' to which the apparatus of the present invention or the method of the present invention can be applied include, for example, argon, ozone gas, oxygen, argon, carbon dioxide gas, and gas. φ Among these, the present invention is particularly applicable to hydrogen-dissolved water. Figure 1 is an engineering system diagram of one aspect of the device of the present invention. The device in this aspect has a dissolving device A for manufacturing specific gas-dissolved water, a water tank B for storing specific gas-dissolved water, a connecting pipe C connecting the dissolving device A and the water tank B, and sending the storage water of the water tank B to the washing machine The pump D, the circulation pipe E that returns from the water tank B to the water tank B through the divergence point between the pump D and the washing machine, and the gas pipe F that supplies gas to the space above the water tank B. The ultrapure water is sent to the dissolving device A through the valve 1, and the specific gas is dissolved to form gas-dissolved water. A water level gauge 2 is provided in the water tank B, and the opening degree of the valve 3 is controlled by a signal sent from the liquid level gauge to keep the water level in the water tank B constant. The gas-dissolved water stored in the water tank B is sent out by the pump D ', and is heated or cooled to a certain temperature by the heat exchanger 4 and fine particles and the like are removed by the purification mechanism 5 provided on the secondary side of the pump. A specific gas concentration of the gas-dissolved water is measured by the gas concentration meter 6. The gas-dissolved water is split at the divergence points 7 and 8 of the circulation pipe E, and sent to the washing machine through the valves 9 and 10, and is used for washing electronic materials and the like. The remaining undissolved gas dissolved water 'is returned to the water tank B through the circulation pipe E. The circulation piping E is provided with -11-• 200536624. A valve 11 is provided to keep the water pressure at the point of use constant. The water tank B is provided with a gas pipe F for supplying gas to the upper space of the water tank B. The gas supplied from the gas pipe F dilutes a specific gas in the upper space of the water tank B, thereby diluting a specific gas concentration in the upper space. Keep it below a certain threshold. In the upper space of the water tank B, a specific gas monitor 1 for monitoring a specific gas concentration in the upper space 1 is provided. 2. An oxygen monitor 1 for monitoring the oxygen concentration in the upper space. 3. A pressure regulator 14 for maintaining the upper space at a positive pressure. . φ In the circulating gas-dissolved water supply device of the present invention, the lower end 15 of the connection pipe C and the lower end 16 of the circulation pipe E are submerged below the water surface in the water tank B. The lower end 15 of the connection pipe C and the lower end 16 of the circulation pipe E are submerged under the water surface in the water tank B, and the specific gas dissolved water is supplied from the connection pipe C to the water tank B, and from the circulation pipe E The specific gas dissolved water returned to the water tank B will not be in contact with the gas phase of the upper space. This prevents the specific gas from volatilizing from the gas dissolved water, reduces the specific gas concentration of the gas dissolved water, and prevents the specific gas concentration of the upper space from rising. ^ In the device of the present invention, it is preferable to supply an inert gas through a gas pipe F. If the specific gas dissolved in water is a dangerous gas such as hydrogen or ozone gas, the inert gas is supplied to the upper space of the water tank B through the gas pipe F, so that the specific gas concentration in the upper space can be reduced and increased. Device security. The inert gas to be supplied is not particularly limited, and examples thereof include nitrogen and rare gases. Among these, nitrogen is preferred. The device of the present invention can be suitably used as a circulating hydrogen dissolved water supply device using hydrogen as a specific gas. Hydrogen-dissolved water is used for cleaning electronic materials -12- 200536624, and it has an excellent effect of removing attached particles. However, when the hydrogen-dissolved water is stored in the water tank B, the space above the water tank B becomes high in the hydrogen concentration. At room temperature and pressure, the lower limit of the explosion of a mixture of hydrogen and air is 4 · 1% by volume of hydrogen. Therefore, when the space above the water tank B becomes a state of high gas concentration, it becomes extremely dangerous. The device of the present invention is used as a circulating hydrogen-dissolved water supply device, and the hydrogen concentration in the upper space of the water tank B can be kept low, so that the hydrogen-dissolved water can be safely supplied to the washing machine. φ In the device of the present invention, it is preferable to provide an oxygen detector or an oxygen concentration meter for monitoring the space above the water tank B when the specific gas is hydrogen. Due to unexpected accidents, the hydrogen concentration in the upper space of the water tank B exceeds 4% by volume, so even if there is a fire source there, if there is no oxygen, no explosion will occur. In the device of the present invention, the inside of the water tank B is constantly maintained at a positive pressure by the pressure regulator 14, so no oxygen is mixed from the outside air to the water tank B. Therefore, the oxygen concentration in the space above the water tank B is usually 0% by volume. However, even if an inert gas is supplied to the upper space of the water tank B, φ will cause a dangerous state if air intrudes. Therefore, by installing an oxygen detector or an oxygen concentration meter, the upper space of the water tank B is monitored. Improves security. The circulating gas-dissolved water supply device of the present invention can be made in a state different from the state shown in Fig. 1. For example, by omitting either of valve 1 and valve 3, and sending a signal from level gauge 2 to the remaining valves to control the opening degree, the water level in water tank B can be kept constant. In addition, the gas concentration meter 6 is used to measure the dissolved gas concentration of the gas dissolved water in the circulation pipe E and the water tank B. It can be used at any position of the circulation pipe E. The gas concentration can be directly measured with a gas meter-13- 200536624. The dissolved gas concentration of the gas in B dissolved water. Furthermore, the exhaust of the specific gas monitor 12 for monitoring the specific gas concentration in the upper space and the oxygen monitor 13 for monitoring the oxygen concentration in the upper space may be discharged outside the system. In the operating method of the circulating gas-dissolved water supply device of the present invention, the circulating gas-dissolved water supply device includes a dissolving device A for manufacturing a specific gas-dissolved water, a water tank B for storing the specific gas-dissolving water, and a connection dissolving device. The connection pipe C between the A and the water tank B, sends the storage water φ of the water tank B to the pump D of the washing machine, and returns from the water tank B to the circulation pipe E of the water tank B through the divergence point between the pump D and the washing machine. The gas is supplied to the gas pipe F in the upper space of the water tank B, and the specific gas dissolved water is supplied to the washing machine at the divergence point, and the remaining specific gas dissolved water is circulated and returned to the water tank B, and the lower end of the pipe C is connected to the circulation The lower end of the piping E is submerged under the water surface in the water tank B, and the volume of the gas dissolved water supplied from the dissolution device A to the water tank B is 100 parts by volume or more to 5 parts by volume with respect to 100 parts by volume of the circulating water. In the device of the present invention, the gas-dissolved water circulating in the circulation pipe is split at the branching point. After being used in the washing machine for washing, the amount of gas-dissolved water returned to the water tank B is reduced, and the amount of gas-dissolved water in the water tank B is reduced. The amount started to decrease. At this time, a drop in the liquid level is detected by the liquid level meter 2 'a signal is sent to the valve 3 to increase the opening degree of the valve, so that gas-dissolved water is supplied from the dissolving device A to the water tank B', so that the height of the liquid level becomes for sure. In the method of the present invention, the variation of the height of the liquid surface of the water tank B is preferably 60% or less of the standard water level, more preferably 40% or less, and more preferably 20% or less. When the change in the liquid level of the water tank exceeds 60% of the standard water level, the lower end of the connecting pipe C and the circulating pipe E -14-200536624 will be difficult to submerge below the water surface, and the gas phase in the space above the water tank B The composition of the device may change, so that the device of the present invention may be difficult to operate stably. Normally, the upper and lower water levels are set by the liquid level gauge 2, and the amount of makeup water from the connecting pipe C is controlled so that the liquid level is formed within the range. In the method of the present invention, When 100 parts by volume of the gas dissolved water sent out are dissolved in the washing machine using more than 5 parts by volume of gas, the amount of gas-dissolved water equal to the amount used for cleaning is supplied from the dissolving device A to the water tank B. In this way, the dissolved gas concentration of the gas-dissolved water can be kept at a predetermined value. However, when the volume of the gas-dissolved water used in the washing machine is less than 5 parts by volume with respect to 1,000 parts by volume of the gas-dissolved water sent by the pump D, it is relative to the gas sent by the pump D. 100 parts by volume of dissolved water 'The amount of gas dissolved water supplied from the dissolving device A to the water tank B is made 5 parts by volume or more. At this time, a part of the gas-dissolved water from the water tank B or the circulation pipe E is released, so that the height of the liquid surface of the water tank B is better. Therefore, the discharge pipe may be provided in advance at any position of the water tank B or the circulating pipe E. When the amount of gas dissolved water $ supplied from the dissolving device A to the water tank B is less than 5 parts by volume relative to 100 parts by volume of the gas dissolved water sent by the pump D, the dissolved gas concentration of the gas-dissolved water will be There is a risk of reduction. In the method of the present invention, when the specific gas is hydrogen, the dissolved hydrogen concentration of the hydrogen dissolved water supplied from the dissolving device A to the water tank B is preferably 0.6 mg / L or more, and is 1.0 mg / L. The above is better. When the particles adhering to the electronic material and the like are washed with hydrogen-dissolved water, a good cleaning effect can be found when the dissolved hydrogen concentration is 0.6 mg / L or more. In addition, the dissolved hydrogen concentration of the hydrogen-dissolved water supplied from the dissolving device A to the water tank B is -15-200536624 degrees to be 1.0 mg / L or more, and the water can be sent from the water tank B to the circulation pipe E through the pump D, and The dissolved hydrogen concentration of the hydrogen-dissolved water used in the washing machine can be easily maintained at 0.6 mg / L or more. In the method of the present invention, when the specific gas is hydrogen, the flow rate of the gas supplied through the gas pipe F is made into a standard state of 0.15 to 5014 relative to the gas-liquid contact area of the water tank B) /1^11.1112 It is better to keep the hydrogen concentration in the space above the water tank 8 below 4.0% by volume. When the flow rate of the gas supplied through the gas pipe F is less than 0.15 L (standard state) / mi η · m2 relative to the gas-liquid contact surface of the water tank B, there will be a hydrogen concentration in the space above the water tank B It may exceed 4.0% by volume. Under normal temperature and pressure, the lower limit of the explosion of the mixed gas of hydrogen and air is hydrogen 4.1% by volume. Therefore, by making the hydrogen concentration in the space above the water tank B below 4,0% by volume, not only the water tank B can be prevented. The internal explosion accident can eliminate the possibility of an explosion accident even when the gas in the space above the water tank b leaks into the atmosphere. When the flow rate of the gas supplied through the gas pipe F exceeds the gas-liquid contact area of the water tank b exceeding 50 L (standard state) / min · m2, the hydrogen gas dissolves water from the hydrogen φ gas into the gas phase in the space above the water tank B Since the volatile amount increases, there is a concern that the dissolved hydrogen concentration of hydrogen dissolved water may decrease. The gas supplied to the space above the water tank B through the gas pipe F can pass through the pressure regulator! 4 and discharged. [Examples] Hereinafter, although the present invention will be described in more detail by taking examples, the present invention is not limited in any way by these examples. In the examples and comparative examples, a cycle test of hydrogen-dissolved water was performed using a gas-dissolved water supply device shown in FIG. 2. This device is equipped with: -16- 200536624 Hydrogen dissolving device a with a gas-permeable membrane made of polypropylene a, a water tank b with a gas-liquid contact area of 0.25 m2 and a volume of 200 L, and a connecting pipe connecting the dissolving device a and the water tank b c. Valve for adjusting the water level of water tank b to less than 6.4 cm 3. Pump d for sending hydrogen-dissolved water from water tank b to circulation pipe e. Heat exchanger for maintaining the temperature of hydrogen-dissolved water at 25 t 4. Filter 5, dissolved hydrogen concentration meter 6, discharge water discharge valve 9, valve 11 for maintaining the pressure in the circulation pipe e at 0.2 MPa, gas pipe f for supplying nitrogen to the space above the water tank b, and at the outlet for supplying gas A pressure regulator 14 for holding a space φ above the water tank b at a positive pressure, and a sensor 12 for measuring the hydrogen concentration in the space above the water tank b. The lower end 15 of the connection pipe c and the lower end 16 of the circulation pipe e are located at a position 10 cm above the bottom of the water tank. Example 1 Hydrogen-dissolved water having a dissolved hydrogen concentration of 1.0 mg / L was prepared in a dissolving device a, and 160 L of hydrogen-dissolved water was poured into a water tank b, and the circulation pipe e was filled with hydrogen-dissolved water. Dissolve hydrogen dissolved water at a concentration of 1.0 mg / L in hydrogen dissolved water at 1.0 OL / min, and supply it to the water tank b from the dissolution φ device a, and send 20 L / min of hydrogen dissolved water from the water tank b to the circulation pipe e through the pump d. The discharged water l.OL / nnn is discharged from the discharged water discharge valve 9, and the hydrogen dissolved water is circulated. Then, 0.5 L (standard state) / min of nitrogen gas was supplied from the gas pipe f to the space above the water tank b. The dissolved hydrogen concentration of the hydrogen-dissolved water measured with the dissolved hydrogen concentration meter 6 was 1.0 mg / L at the start of operation, 0.88 mg / L after 1 hour, 0.75 mg / L after 2 hours, and 3 hours later. 0.68 mg / L, 0.66 mg / L after 4 hours, 0,65 mg / L after 5 hours, and 0.65 mg / L after 6 hours. The hydrogen concentration in the upper space of the water tank b is set to be 0.0% by volume from the beginning of the operation to 18 hours later. Comparative Example 1 Except that the dissolved hydrogen gas having a dissolved hydrogen concentration of 1.0 mg / L was dissolved in water of 0.5 L / mi, η was supplied from the dissolution device a to the water tank b, and the discharged water was discharged from the discharged water discharge valve 9 by 0.5 L / nnn. Other than that, in the same manner as in Example 1, 20 L / min of hydrogen-dissolved water was sent from the water tank b to the circulation pipe e by the pump d to circulate the hydrogen-dissolved water. The dissolved hydrogen concentration g of the hydrogen-dissolved water measured using the dissolved hydrogen concentration meter 6 was 1.0 mg / L at the start of operation, 0.85 mg / L after 1 hour, 0.73 mg / L after 2 hours, and 3 hours later. 0.65 mg / L, 0.57 mg / L after 4 hours, 0.53 mg / L after 5 hours, and 0.49 mg / L after 6 hours ° Comparative Example 2 Except that the hydrogen from the dissolution device a to the water tank b was not performed Except for the supply of dissolved water and the discharge of water from the discharge water discharge valve 9, the same as in Example 1, 20 L / min of hydrogen dissolved water was sent from the water tank b to the circulation pipe e by the pump d to dissolve the hydrogen. Water cycle. The dissolved S gas of hydrogen dissolved water measured by the dissolved hydrogen concentration meter 6? Agricultural grade, 1.0 mg / L at the start of operation, 0.83 mg / L after 1 hour, 0.6 9 mg / L after 2 hours, 0.4 9 mg / L after 3 hours, and 0.35 after 4 hours mg / L, 0.25 mg / L after 5 hours, and 0.21 mg / L after 6 hours. Example 2 Except for the amount of nitrogen supplied from the gas pipe f to the upper space of the water tank b, 0.03 75 L ( Except for the standard state) / min, the same as in Example 1 was used. 1. Dissolved hydrogen with a concentration of 1.0 mg / L of hydrogen dissolved water l.OL / min was supplied from the dissolution device a to the water tank b, and hydrogen dissolved water 20 L / min was borrowed. The pump d is sent from the water-18-200536624 tank b to the circulation pipe e, and the discharged water is discharged from the discharge water discharge valve 9 at a rate of 1.0 OL / min, so that the hydrogen-dissolved water is circulated. The dissolved hydrogen concentration of the hydrogen-dissolved water measured using the dissolved hydrogen concentration sensor 6 was 1.0 mS / L at the start of operation, 0.88 mg / L after 1 hour, 0.75 mg / L after 2 hours, and 3 hours later. 0.88 mg / L, 0.66 mg / L after 4 hours, 0.65 mg / L after 5 hours, and 0.65 mg / L after 6 hours. The hydrogen concentration in the upper space of the water tank b measured by the hydrogen concentration sensor 12 was 0.53% by volume at the start of operation, 1.48% by volume after 2 hours, and 2.52% by volume after 4 hours. 3.13 vol% after 6 hours, 3.39 vol% after 8 hours, 3.59 vol% after 10 hours, 3.5 vol% after 12 hours, 14 hours Later, after 16 hours and after 18 hours, they were 3.64% by volume. Comparative Example 3 The same procedure as in Example 1 was performed except that nitrogen was not supplied from the gas pipe f to the upper space of the water tank b. The dissolved hydrogen having a dissolved hydrogen concentration of 1.0 mg / L was dissolved in 1.0 ml / min from the dissolution device. a is supplied to the water tank b, and the hydrogen-dissolved water 2 OL / min is sent from the water tank b to the circulation pipe e by the pump d, and the discharged water 丨 .OL / min is discharged from the discharge water discharge valve 9 to circulate the hydrogen-dissolved water. The hydrogen concentration in the upper space of the water tank b measured by the hydrogen concentration sensor 12 was 0.53% by volume at the start of operation, 1.77% by volume after 2 hours, 2.79% by volume after 4 hours, 3.49 vol% after 6 hours, 3.73 vol% after 8 hours, 3.88 vol% after 10 hours, 3.98 vol% after 12 hours, 4.0 2 vol% after 14 hours, and 4.0 7 after 16 hours 10% by volume after 18 hours. The operating conditions of Examples 1 to 2 and Comparative Examples 1 to 3 are shown in Table 1. 'The time-dependent change of the dissolved hydrogen concentration of hydrogen-dissolved water is shown in FIG. 3 and the upper part of the water tank b is shown in FIG. 19-200536624. The temporal change of the hydrogen concentration in the space is not obvious in Fig. 4. [Table 1] Hydrogen-dissolved water replenishment with respect to 100 vol. Of nitrogen flow rate (L / min) parts of make-up water (vol. Parts) (L / min · m2) Example 1 1.0 5 2.0 Comparative Example 1 0.5 2.5 2.0 Comparative Example 2 0 0 2.0 Example 2 1.0 5 0.15 Comparative Example 3 1.0 5 0 As can be seen from the figure 3, the volume of hydrogen dissolved water sent from the water tank b to the circulation pipe e by the pump d is 100 vol. The portion of the dissolved hydrogen concentration of the hydrogen-dissolved water sent from the water tank b in Example 1 in which 5 parts by volume of hydrogen-dissolved water was replenished from the dissolving device a, must be maintained in order to be used as washing water for removing particles. Above 6mg / L. On the other hand, "Compared to Comparative Example 1 in which hydrogen dissolved water is supplied from the dissolving device a to 2 · 5 parts by volume of hydrogen dissolved water from the water tank b by the pump d to the circulation pipe e" The dissolved hydrogen concentration of the gas-dissolved water sent from the water tank b is reduced to 0.6 mg / L or less. In Comparative Example 2 in which hydrogen dissolved water was not supplied to the water tank b from the dissolution device a, the dissolved hydrogen concentration of the hydrogen dissolved water sent from the water tank b rapidly decreased. From this result, it can be understood that the dissolved hydrogen concentration of the hydrogen-dissolved water supplied from the hydrogen-dissolving device a to the water tank b is made to 1.0 mg / L, and the replenishment amount of the hydrogen-dissolved water is sent from the water tank b by the pump d. When the volume of water to the circulation pipe e is 100 parts by volume, and when it is made to be 5 parts by volume or more, the dissolved hydrogen concentration of the hydrogen dissolved water sent to the circulation -20- 200536624 pipe e can be maintained to be sufficient as washing water. The performance is above 0.6mg / L. As shown in FIG. 4, the gas-liquid contact area of the water tank b with respect to the space above the water tank b is in Example 1 in which nitrogen gas of 2 · 0 L (standard state) / min · m2 is supplied through the gas pipe f. 'The hydrogen concentration in the upper space of the water tank b is 0% by volume, and in the second embodiment of supplying the nitrogen gas of 0.15 L (standard state) / mi η · m2 through the gas pipe f', the nitrogen concentration in the upper space of the water tank b It is stable at 3.6 4% by volume. In contrast, in the "Comparative Example 3 in which nitrogen was not supplied to the upper space of the water tank b", the hydrogen concentration in the upper space of the water tank b after 18 hours reached the lower limit of the explosion of the mixed gas of hydrogen and air 4.1. Volume%, and tends to rise slightly. From this result, it can be understood that the upper portion of the water tank b can be supplied by supplying 0.15L (standard state) / min · m2 of nitrogen gas to the upper space of the water tank b through the gas pipe f relative to the gas-liquid contact area of the water tank b. The hydrogen concentration in the space is kept below 4.0% by volume. [Feasibility of industrial use] According to the circulating gas-dissolved water supply device of the present invention and the operating method of the device, a gas-dissolved washing water using a specific gas used in a wet cleaning process in which electronic materials and the like are dissolved, The gas-dissolved washing water that is not used in the washing machine can be returned to the water tank, and the specific gas concentration of the dissolved gas-dissolved washing water can be maintained above a certain level, and the storage tank can be used to dissolve the water in the water tank The concentration of the specific gas in the upper space is kept low. The device and method of the present invention are suitable for hydrogen dissolved water, so that the concentration of dissolved hydrogen is maintained high and a sufficient cleaning effect is exerted, and the hydrogen concentration in the upper space of the water tank storing the hydrogen dissolved water is kept low, so it can be safely used Hydrogen dissolves water to clean electronic materials. -21- 200536624 [Brief description of the drawings] Figure 1 is an engineering system diagram of one form of the device of the present invention. Fig. 2 is an explanatory diagram of a device used in the embodiment. Fig. 3 is a graph showing the change over time of the dissolved hydrogen concentration of hydrogen dissolved water. Figure 4 is a graph showing the hydrogen concentration in the space above the water tank over time. [Description of main component symbols] A, a ... dissolution device B, b ... water tank C, c ... connection piping D, d ... chestnut E, e ... circulation piping F, f ... gas piping 1, 3, 9, 1 0, 1 1… valve 2… level meter 4… heat exchanger 5… purification mechanism® 6… gas concentration meter 7, 8… divergence point 12… specific gas monitor 13… oxygen monitor 14… pressure regulator 15… connection Lower end of piping 16 ... lower end of circulating piping -22-