JPH0771669B2 - Ultrapure water production method - Google Patents
Ultrapure water production methodInfo
- Publication number
- JPH0771669B2 JPH0771669B2 JP2225367A JP22536790A JPH0771669B2 JP H0771669 B2 JPH0771669 B2 JP H0771669B2 JP 2225367 A JP2225367 A JP 2225367A JP 22536790 A JP22536790 A JP 22536790A JP H0771669 B2 JPH0771669 B2 JP H0771669B2
- Authority
- JP
- Japan
- Prior art keywords
- water
- ion exchange
- fine particles
- ultrapure water
- treated
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Separation Using Semi-Permeable Membranes (AREA)
- Treatment Of Water By Ion Exchange (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は超純水の製造法に関するものである。詳しく
は、被処理水中に存在する微生物、土壌成分、金属酸化
物等の微粒子を効果的に吸着除去することにより、例え
ば半導体製造工程のウエハーの洗浄用として好適な超純
水を製造する方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for producing ultrapure water. Specifically, it relates to a method for producing ultrapure water suitable for cleaning wafers in a semiconductor manufacturing process, for example, by effectively adsorbing and removing fine particles such as microorganisms, soil components, and metal oxides present in water to be treated. It is a thing.
（従来の技術） 近年、超純水は半導体工業、医薬品工業等の広い分野に
使用されており、特に半導体工業においては、主力製品
である半導体素子がIC、LSI、VLSIへとその集積度、い
わゆるビツト数が経年的に上昇し、このため極めて高純
度の超純水が要求されるようになった。(Prior Art) In recent years, ultrapure water has been used in a wide range of fields such as the semiconductor industry and the pharmaceutical industry. Particularly in the semiconductor industry, semiconductor devices, which are the main products, are integrated into ICs, LSIs, and VLSIs. The so-called bit number has increased over the years, which has led to the demand for extremely pure ultrapure water.
半導体素子の製造工程におけるウエハーの洗浄用に使用
される超純水の純度の管理指標としては、電気伝導率
（又は比抵抗）はもとより、その他の管理指標として全
有機炭素、生菌数、微粒子数、溶存酸素量等にまで及ん
でいる。特に超純水中に存在する微生物、土壌成分、金
属酸化物等により構成される微粒子を極力微量化するこ
とは、半導体素子製造における製品歩留り向上の大きな
要因となるため、微粒子数が極めて少ない、例えば粒径
0.1μｍ以上の粒子として数個〜数十個/ml程度までの超
純水を製造することが望まれている。As a control index for the purity of ultrapure water used for cleaning wafers in the semiconductor element manufacturing process, not only electrical conductivity (or specific resistance) but also other control indices such as total organic carbon, viable cell count, fine particles It reaches the number and the amount of dissolved oxygen. In particular, minimizing the amount of microparticles composed of microorganisms, soil components, metal oxides, etc. present in ultrapure water is a major factor in improving the product yield in semiconductor device manufacturing, so the number of microparticles is extremely small, Particle size
It is desired to produce ultrapure water in the range of several to several tens / ml as particles of 0.1 μm or more.
従来、超純水を製造するには、被処理水として上水、河
川水、地下水等を使用し、これらを、凝集濾過器、２床
２塔式乃至２床３塔式のイオン交換塔及び混床式イオン
交換塔等のイオン交換装置、逆浸透膜及び精密濾過膜等
の膜装置から構成される一次純水系システムと、紫外線
殺菌器、イオン交換塔、限外濾過膜及び逆浸透膜等の膜
装置から構成される二次純水系システムとからなる超純
水製造システムにより処理し、被処理水中のイオン性不
純物、有機物、及び微生物、土壌成分、金属酸化物、並
びに溶存酸素等の不純物を極限近くまで除去する方法が
採用されている。Conventionally, in order to produce ultrapure water, tap water, river water, groundwater, etc. have been used as water to be treated, and these are treated with a coagulation filter, a two-bed two tower type to a two-bed three tower type ion exchange tower, and Primary pure water system consisting of ion exchange equipment such as mixed bed type ion exchange tower, membrane equipment such as reverse osmosis membrane and microfiltration membrane, and ultraviolet sterilizer, ion exchange tower, ultrafiltration membrane and reverse osmosis membrane, etc. Processed by the ultrapure water production system consisting of the secondary pure water system composed of the membrane device, and the impurities such as ionic impurities, organic matters, microorganisms, soil components, metal oxides and dissolved oxygen in the water to be treated. Has been adopted to remove as much as possible.
この方法では、被処理水中のイオン性不純物は主として
イオン交換塔で除去され、微生物、土壌成分、金属酸化
物等の微粒子は主として逆浸透膜、限外濾過膜等の膜装
置により除去される。このため、超純水製造システムに
よる処理では、イオン交換塔から流出する処理水につい
ては、専ら処理水中に漏出するイオン性不純物が注目さ
れ、処理水の純度管理の指標としては主として電気伝導
率が採用されており、処理水中に同伴して漏出する微粒
子については全く顧慮されていないのが実状であった。In this method, ionic impurities in the water to be treated are mainly removed by an ion exchange tower, and fine particles such as microorganisms, soil components and metal oxides are mainly removed by a membrane device such as a reverse osmosis membrane and an ultrafiltration membrane. Therefore, in the treatment by the ultrapure water production system, regarding the treated water flowing out from the ion exchange tower, the ionic impurities leaking into the treated water are the focus of attention, and the electrical conductivity is the main indicator of the purity control of the treated water. It has been adopted, and the fact is that no consideration has been given to the fine particles that accompany and leak into the treated water.
イオン交換塔から流出する処理水中に微粒子が漏出する
と、イオン交換塔に後続する膜装置の負荷が増大し、結
果として、最終的に得られる超純水中に漏出する微粒子
が増加することになる。また、漏出した微粒子により膜
装置が閉塞するのを阻止するために、膜装置を定期的に
洗浄又は交換することが必要であるが、これにより、超
純水の供給が中断されるという不都合を生じる。If fine particles leak into the treated water flowing out from the ion exchange tower, the load on the membrane device following the ion exchange tower will increase, and as a result, the fine particles leaking into the ultrapure water finally obtained will increase. . Further, in order to prevent the membrane device from being blocked by the leaked fine particles, it is necessary to regularly clean or replace the membrane device, but this causes a disadvantage that the supply of ultrapure water is interrupted. Occurs.
（発明が解決しようとする課題） 本発明は、従来技術による上述の問題点を解決し、イオ
ン交換塔から流出する処理水への微粒子の漏出を極力制
御することにより、微粒子の漏洩による支障を生ずるこ
とのない超純水製造プロセスを提供することを目的とす
るものである。(Problems to be Solved by the Invention) The present invention solves the above-mentioned problems of the prior art and controls the leakage of fine particles to the treated water flowing out from the ion exchange tower as much as possible, thereby preventing the obstacles due to the leakage of fine particles. It is intended to provide an ultrapure water production process that does not occur.
（課題を解決するための手段） 本発明者等は、上記の目的を達成するために、超純水製
造システムにおける不純物の挙動、特にイオン交換塔の
周辺における微粒子の挙動について検討した結果、イオ
ン交換塔に充填されるイオン交換樹脂はイオン交換能力
の外に微粒子に対する吸着能力をも併せ有し、またイオ
ン交換塔から処理水中に漏出する微粒子はイオン性不純
物より先行して漏出することを見い出した。(Means for Solving the Problems) In order to achieve the above object, the present inventors have examined the behavior of impurities in an ultrapure water production system, in particular, the behavior of fine particles in the vicinity of an ion exchange column. It was found that the ion exchange resin packed in the exchange tower has not only the ion exchange capacity but also the adsorption capacity for fine particles, and that the fine particles leaking from the ion exchange tower into the treated water leak before the ionic impurities. It was
本発明は上記の知見に基づいて更に検討を重ねた結果達
成されたもので、その要旨は、被処理水を、イオン交換
樹脂処理次いで膜処理を含む工程により処理して超純水
を製造する方法において、イオン交換樹脂処理後の処理
水中の微粒子数を測定し、該微粒子数が所定の値に達し
た時点でイオン交換樹脂の再生処理を行うことを特徴と
する超純水の製造法に存する。The present invention has been achieved as a result of further studies based on the above findings, and the gist thereof is to produce ultrapure water by treating water to be treated by a step including ion exchange resin treatment and then membrane treatment. In the method, the method for producing ultrapure water is characterized in that the number of fine particles in the treated water after the ion exchange resin treatment is measured, and when the number of fine particles reaches a predetermined value, the ion exchange resin is regenerated. Exist.
以下に本発明を詳細に説明する。The present invention will be described in detail below.
超純水の製造システムとしては、種々の方式が検討され
ているが、代表的な超純水製造システムの一例のフロー
チャートを第１図に示す。第１図の製造システムは、凝
集濾過器、２床３塔式イオン交換塔、逆浸透膜装置及び
混床式イオン交換塔から構成される一次系純水システム
と、一次系純水システムによる処理水を更に高純度化す
るための、紫外線殺菌器、混床式イオン交換塔及び限外
濾過膜装置から構成される二次系純水システムとからな
る。本発明は第１図に示す超純水製造システムに適用さ
れるが、他の如何なるシステムにも適用することができ
る。Various systems have been studied as a system for producing ultrapure water, and a flowchart of an example of a typical system for producing ultrapure water is shown in FIG. The manufacturing system shown in FIG. 1 is a primary system pure water system composed of a coagulation filter, a two-bed three-column type ion exchange column, a reverse osmosis membrane device, and a mixed-bed type ion exchange column, and treatment by the primary system pure water system. It is composed of a secondary pure water system composed of an ultraviolet sterilizer, a mixed bed type ion exchange tower and an ultrafiltration membrane device for further purifying water. The present invention is applied to the ultrapure water production system shown in FIG. 1, but can be applied to any other system.
第１図の超純水製造システムにおける２床３塔式イオン
交換塔は、強酸性陽イオン交換樹脂充填塔、脱炭酸塔及
び強塩基性陰イオン交換樹脂充填塔からなり、また混床
式イオン交換塔は、強酸性陽イオン交換樹脂と強塩基性
陰イオン交換樹脂とを混合状態で充填した塔からなるも
のである。これらのイオン交換塔の機能としては、主と
して被処理水中のイオン性不純物を除去することを目的
し、イオン性不純物の漏出が可及的に少ない処理水が得
られるように、イオン交換容量及び機械的強度の大きい
イオン交換樹脂が使用される。The two-bed, three-column type ion exchange column in the ultrapure water production system of FIG. 1 is composed of a strongly acidic cation exchange resin packed column, a decarboxylation column and a strongly basic anion exchange resin packed column, and also a mixed bed type ion The exchange column is a column packed with a strongly acidic cation exchange resin and a strongly basic anion exchange resin in a mixed state. The function of these ion exchange towers is mainly to remove ionic impurities in the water to be treated, so that the treated water with the least leakage of ionic impurities can be obtained, and the ion exchange capacity and mechanical An ion exchange resin having a high mechanical strength is used.
このようなイオン交換樹脂としては、例えばスチレンと
ジビニルベンゼン（架橋剤）とを共重合して得られる架
橋共重合体を母体とする市販の各種強酸性陽イオン交換
樹脂及び強塩基性陰イオン交換樹脂が使用される。強酸
性陽イオン交換樹脂の例としては、ダイヤイオンSK1B、
SK110、SKN等が挙げられ、また強塩基性陰イオン交換樹
脂の例としてはダイヤイオンSA10A、PA312（ダイヤイオ
ンは三菱化成社の登録商標）等が挙げられる。Examples of such an ion exchange resin include various commercially available strong acid cation exchange resins and strong basic anion exchange resins having a cross-linked copolymer obtained by copolymerizing styrene and divinylbenzene (cross-linking agent) as a base. Resin is used. Examples of strong acid cation exchange resins include Diaion SK1B,
Examples thereof include SK110 and SKN, and examples of the strongly basic anion exchange resin include DIAION SA10A and PA312 (DIAION is a registered trademark of Mitsubishi Kasei).
上記の超純水製造システムにおいては、イオン交換塔に
上記のイオン交換樹脂を充填し常法により樹脂を再生し
た後、被処理水を通液する。被処理水の流通を継続する
につれて、イオン交換樹脂のイオン交換能力及び微粒子
に対する吸着能力は漸次減少し、これに伴ってイオン交
換塔から流出する処理水中に漏出するイオン性不純物及
び微粒子数も漸次増大する。この場合、イオン交換塔か
ら処理水中に漏出する微粒子は、イオン性不純物よりも
先行して流出する。また電気伝導率（又は比抵抗）の測
定による水質管理では漏出する微粒子数を把握すること
ができない。In the above ultrapure water production system, the ion exchange tower is filled with the above ion exchange resin, the resin is regenerated by a conventional method, and then the water to be treated is passed through. As the water to be treated continues to flow, the ion exchange capacity of the ion exchange resin and the adsorption capacity for fine particles gradually decrease, and the number of ionic impurities and fine particles leaking into the treated water flowing out from the ion exchange tower also gradually decrease accordingly. Increase. In this case, the fine particles leaking from the ion exchange tower into the treated water flow out before the ionic impurities. In addition, the number of leaked fine particles cannot be grasped by water quality control by measuring electric conductivity (or specific resistance).
本発明の方法は、イオン交換塔から流出する処理水の出
口付近に微粒子計を設置し、処理水中に漏出する微粒子
数が所定の値に達した時点で通液を停止してイオン交換
樹脂の再生処理を実施するものである。微粒子計の設置
場所としては、２床２塔式又は２床３塔式イオン交換塔
では、後段の陰イオン交換塔の出口付近が好ましい。ま
た、混床式イオン交換塔において塔の出口近傍に設置す
るのがよい。微粒子計としては、例えばPLCA−310（堀
場製作所製）、ZRV（富士電機社製）、TK−200（日本錬
水社製）等の市販品が使用される。In the method of the present invention, a fine particle meter is installed in the vicinity of the outlet of the treated water flowing out from the ion exchange tower, and when the number of fine particles leaking into the treated water reaches a predetermined value, the passage of the ion exchange resin is stopped. A reproduction process is performed. In the case of a two-bed, two-column type or two-bed, three-column type ion exchange column, the location of the fine particle meter is preferably near the outlet of the anion exchange column in the subsequent stage. Further, it is preferable to install it in the vicinity of the exit of the mixed bed type ion exchange tower. As the fine particle meter, commercially available products such as PLCA-310 (manufactured by Horiba, Ltd.), ZRV (manufactured by Fuji Electric Co., Ltd.) and TK-200 (manufactured by Nippon Rensui Co., Ltd.) are used.
イオン交換樹脂処理後、処理水中の微粒子数が所定の値
に達した時点でのイオン交換樹脂の再生には、通常の超
純水製造システムにおけるイオン交換樹脂の再生処理が
適用される。またカートリッジ式のイオン交換塔の場合
は、予め再生済のイオン交換樹脂を充填したカートリッ
ジと交換すればよい。再生処理後のイオン交換塔は、処
理水で充分に洗浄した後、再び超純水の製造に供され
る。After the ion exchange resin treatment, the regeneration treatment of the ion exchange resin in a normal ultrapure water production system is applied to the regeneration of the ion exchange resin when the number of fine particles in the treated water reaches a predetermined value. Further, in the case of a cartridge type ion exchange tower, it may be exchanged with a cartridge filled with a regenerated ion exchange resin in advance. The ion exchange tower after the regeneration treatment is thoroughly washed with treated water and then used again for the production of ultrapure water.
（実施例） 次に本発明を実施例により、更に詳細に説明するが、本
発明はその要旨を超えない限り、以下の実施例に限定さ
れるものではない。(Examples) Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples as long as the gist thereof is not exceeded.
実施例１ 直径30mm、長さ2000mmのカラムに720mlの強酸性陽イオ
ン交換樹脂ダイヤイオンSKNを充填し、上記と同一容量
の別のカラムに再生処理した720mlのゲル型強塩基性陰
イオン交換樹脂ダイヤイオンSA10Aを充填し、両者カラ
ムを直列に連結して２床２塔式イオン交換塔を形成させ
た。被処理水として横浜市水に亜硫酸ナトリウムを添加
して残留塩素を除去して得られた次の表１に示す組成を
有する水を、陽イオン交換カラム次いで陰イオン交換カ
ラムの順に流速40m/hrで流通し、陰イオン交換カラムか
ら流出する処理水中の粒径0.1μｍ以上の微粒子数が10,
000個/mlになるまで通水した時点で通水を停止した。Example 1 A column having a diameter of 30 mm and a length of 2000 mm was packed with 720 ml of a strongly acidic cation exchange resin, DIAION SKN, and another column having the same volume as above was regenerated and treated with 720 ml of a gel-type strongly basic anion exchange resin. Diaion SA10A was packed, and both columns were connected in series to form a two-bed two-column type ion exchange column. The water having the composition shown in the following Table 1 obtained by adding sodium sulfite to Yokohama city water as the water to be treated to remove residual chlorine was flown in the order of cation exchange column and anion exchange column at a flow rate of 40 m / hr. The number of fine particles with a particle size of 0.1 μm or more in the treated water flowing out of the anion exchange column is 10,
The water flow was stopped when the water flow reached to 000 / ml.
陰イオン交換カラムから流出した処理水中の微粒子数を
微粒子計（堀場製作所製PLCA−310）を用いて測定し、
同時に電気伝導率をカスタムレコーダー（東亜電被工業
社製EPR−221E）を用いて測定した。その結果を第２図
に示す。第２図は通水量と処理水の電気伝導率及び微粒
子数との関係を表し、通水量の増大に伴って処理水中の
微粒子数が増加し、特に通水量がイオン交換樹脂量の20
0倍（容量）を超えると微粒子数が著しく増大すること
を示している。 The number of fine particles in the treated water flowing out from the anion exchange column was measured using a fine particle counter (PLCA-310 manufactured by Horiba Ltd.),
At the same time, the electric conductivity was measured using a custom recorder (EPR-221E manufactured by Toa Denki Kogyo KK). The results are shown in FIG. Fig. 2 shows the relationship between the water flow rate, the electrical conductivity of treated water, and the number of fine particles. The number of fine particles in the treated water increases as the water flow rate increases.
It is shown that the number of fine particles significantly increases when it exceeds 0 times (capacity).
通水処理後の陽イオン交換カラム及び陰イオン交換カラ
ムは、常法により塩酸及び苛性ソーダ水溶液で夫々再生
処理した。再生処理後のイオン交換カラムに、上記と同
様にして通水処理した場合も第２図とほぼ同様の結果が
得られた。The cation exchange column and the anion exchange column after the water flow treatment were regenerated by a conventional method with hydrochloric acid and a caustic soda aqueous solution, respectively. When water was passed through the ion exchange column after the regeneration treatment in the same manner as above, almost the same results as in FIG. 2 were obtained.
実施例２ 400lの強酸性陽イオン交換樹脂ダイヤイオンSKN及び900
lの強塩基性陰イオン交換樹脂ダイヤイオンSA10Aをカラ
ムに充填して混床式イオン交換塔を形成させた。このイ
オン交換塔を常法により再生処理した後、25℃での比抵
抗が4.1MΩ・cmで粒径0.1μｍ以上の微粒子数1800個/ml
を含む組成の被処理水を通水流量22.5m3/hrで通水し
た。混床式イオン交換カラムから流出する処理水中の微
粒子数及び比抵抗を実施例１で用いた微粒子計及びカス
タムレコーダーにより測定した。その結果を第３図に示
す。第３図は通水量と処理水の比抵抗及び微粒子数との
関係を表し、通水量がイオン交換樹脂量の1000倍（容
量）を超えると処理水中の微粒子数が増加することを示
している。Example 2 400 l of strongly acidic cation exchange resin Diaion SKN and 900
The column was packed with l of strongly basic anion exchange resin DIAION SA10A to form a mixed bed type ion exchange column. After regenerating this ion-exchange tower by a conventional method, the specific resistance at 25 ° C is 4.1 MΩ · cm, and the number of particles with a particle size of 0.1 μm or more is 1800 particles / ml.
Water to be treated having a composition containing was passed at a flow rate of 22.5 m 3 / hr. The number of fine particles in the treated water flowing out from the mixed bed type ion exchange column and the specific resistance were measured by the fine particle meter and the custom recorder used in Example 1. The results are shown in FIG. FIG. 3 shows the relationship between the water flow rate, the specific resistance of treated water and the number of fine particles, and shows that the number of fine particles in the treated water increases when the water flow rate exceeds 1000 times (volume) of the amount of ion exchange resin. .
（発明の効果） 本発明の方法は、超純水製造システムにおけるイオン交
換塔から流出する処理水中の微粒子数を、塔の出口付近
に設置した微粒子計で測定し、微粒子数が所定の値に達
した時点でイオン交換樹脂を再生することにより後続す
る膜装置の負荷を軽減し、微粒子の混入が極めて微量の
高純度の超純水を得ることができる。また膜装置の洗浄
又は交換の頻度を低減することができるので超純水の工
業的製造に寄与するところは大きい。(Effect of the invention) The method of the present invention measures the number of fine particles in the treated water flowing out from the ion exchange column in the ultrapure water production system with a fine particle meter installed near the outlet of the column, and the number of fine particles reaches a predetermined value. By regenerating the ion-exchange resin at the time when it reaches, it is possible to reduce the load on the subsequent membrane device and obtain ultrapure water of high purity with a very small amount of fine particles mixed therein. Further, since the frequency of cleaning or replacement of the membrane device can be reduced, it greatly contributes to the industrial production of ultrapure water.
第１図は超純水製造システムの一例のフローチャート、
第２図は通水量と電気伝導率及び微粒子数との関係を示
し、第２図中の曲線１は電気伝導率を、曲線２は微粒子
数を夫々示す。第３図は通水量と比抵抗及び微粒子数と
の関係を示し、第３図中の曲線１は比抵抗を、曲線２は
微粒子数を夫々示す。FIG. 1 is a flowchart of an example of an ultrapure water production system,
FIG. 2 shows the relationship between the water flow rate, the electric conductivity, and the number of fine particles. In FIG. 2, curve 1 shows the electric conductivity, and curve 2 shows the number of fine particles. FIG. 3 shows the relationship between the water flow rate and the specific resistance and the number of fine particles. In FIG. 3, curve 1 shows the specific resistance and curve 2 shows the number of fine particles.
フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 ＦＩ 技術表示箇所 Ｃ０２Ｆ 9/00 Ｈ Ｊ Ｎ Ｐ ５０３ Ｂ ５０４ Ｂ Ｄ (72)発明者 福本 隼明 兵庫県伊丹市瑞原４丁目１番地 三菱電機 株式会社エル・エス・アイ研究所内 (56)参考文献 特開 平１−218680（ＪＰ，Ａ)Continuation of front page (51) Int.Cl. 6 Identification number Office reference number FI Technical indication location C02F 9/00 HJN P 503 B 504 B D (72) Inventor Fukumoto Hayakumei 4 Mizuohara, Itami City, Hyogo Prefecture No. 1 MITSUBISHI ELECTRIC CO., LTD. LSI Research Laboratory (56) Reference JP-A-1-218680 (JP, A)
Claims (1)
処理を含む工程により処理して超純水を製造する方法に
おいて、イオン交換樹脂処理後の処理水中の微粒子数を
測定し、該微粒子数が所定の値に達した時点でイオン交
換樹脂の再生処理を行うことを特徴とする超純水の製造
法。1. A method for producing ultrapure water by treating water to be treated by a step including an ion-exchange resin treatment and then a membrane treatment, wherein the number of fine particles in the treated water after the ion-exchange resin treatment is measured to obtain the fine particles. A method for producing ultrapure water, which comprises regenerating an ion-exchange resin when the number reaches a predetermined value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2225367A JPH0771669B2 (en) | 1990-08-29 | 1990-08-29 | Ultrapure water production method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2225367A JPH0771669B2 (en) | 1990-08-29 | 1990-08-29 | Ultrapure water production method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04108587A JPH04108587A (en) | 1992-04-09 |
| JPH0771669B2 true JPH0771669B2 (en) | 1995-08-02 |
Family
ID=16828240
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2225367A Expired - Fee Related JPH0771669B2 (en) | 1990-08-29 | 1990-08-29 | Ultrapure water production method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0771669B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5172859B2 (en) * | 2007-01-19 | 2013-03-27 | ザ・ピュロライト・カンパニー | Reduced reverse osmosis membrane contamination |
| JP5077266B2 (en) * | 2009-02-26 | 2012-11-21 | 日本錬水株式会社 | Pure water production equipment |
| RU2577379C1 (en) * | 2011-11-30 | 2016-03-20 | Ром Энд Хаас Компани | Treatment of sewage water from coking |
| JP6228531B2 (en) * | 2014-12-19 | 2017-11-08 | 栗田工業株式会社 | Ultrapure water production apparatus and ultrapure water production method |
-
1990
- 1990-08-29 JP JP2225367A patent/JPH0771669B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04108587A (en) | 1992-04-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3200301B2 (en) | Method and apparatus for producing pure or ultrapure water | |
| JP5081690B2 (en) | Production method of ultra pure water | |
| KR100784438B1 (en) | apparatus and method for continuous electrodeionization | |
| CN106548816A (en) | A kind of knockdown Spent Radioactive water treatment facilities | |
| KR100769919B1 (en) | Ascites desalination | |
| JPH0328797A (en) | Method for removeing suspensible impurity of condensate by mixed end type condensate desalting device | |
| JP4943377B2 (en) | Condensate demineralization method and condensate demineralization apparatus | |
| US3849306A (en) | Process and apparatus for removing impurities from condensate water | |
| JP3687829B2 (en) | Condensate treatment method and condensate demineralizer | |
| JPH0771669B2 (en) | Ultrapure water production method | |
| JP2012016673A (en) | Device and method of treating iodine/boron-containing solution | |
| JP5499433B2 (en) | Ultrapure water manufacturing method and apparatus, and electronic component member cleaning method and apparatus | |
| JPH054051A (en) | Ion exchange resin for producing ultrapure water, method for producing the same, and method for producing ultrapure water using the same | |
| KR20190046718A (en) | Operation method of water quality management system and water quality management system | |
| CN106746049A (en) | A kind of ultrapure water production system and its production method | |
| JPH04108588A (en) | Production of ultrapure water | |
| JP3173049B2 (en) | Anion exchange resin for ultrapure water production and ultrapure water production method using the same | |
| JPH03151092A (en) | Column for producing ultra-pure water | |
| JP4383091B2 (en) | Condensate desalination method and apparatus | |
| JP3614548B2 (en) | Hydrogen peroxide purification method | |
| JPH074592B2 (en) | Ultrapure water production method | |
| JPH05138162A (en) | Ultrapure water production method | |
| JP2941121B2 (en) | Ultrapure water production equipment | |
| JPH0142754B2 (en) | ||
| JP2003010849A (en) | Secondary pure water production equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees | ||
| S111 | Request for change of ownership or part of ownership |
Free format text: JAPANESE INTERMEDIATE CODE: R313115 |
|
| R371 | Transfer withdrawn |
Free format text: JAPANESE INTERMEDIATE CODE: R371 |