JPH0790215B2 - Method for removing dissolved carbon dioxide gas in pure water production equipment - Google Patents
Method for removing dissolved carbon dioxide gas in pure water production equipmentInfo
- Publication number
- JPH0790215B2 JPH0790215B2 JP61172135A JP17213586A JPH0790215B2 JP H0790215 B2 JPH0790215 B2 JP H0790215B2 JP 61172135 A JP61172135 A JP 61172135A JP 17213586 A JP17213586 A JP 17213586A JP H0790215 B2 JPH0790215 B2 JP H0790215B2
- Authority
- JP
- Japan
- Prior art keywords
- carbon dioxide
- reverse osmosis
- water
- dioxide gas
- pure water
- 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 - Lifetime
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- Separation Using Semi-Permeable Membranes (AREA)
- Physical Water Treatments (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は、半導体工業用の超純水装置、ボイラー給水用
の純水装置等、逆浸透法とイオン交換法とを併用して純
水をつくる純水製造装置における溶存炭酸ガスの除去方
法に関する。DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is an ultrapure water device for the semiconductor industry, a pure water device for boiler water supply, etc. The present invention relates to a method for removing dissolved carbon dioxide gas in a pure water producing apparatus for producing water.
（従来の技術） 半透膜を用いる逆浸透装置による水を処理する場合、カ
ルシウム、ナトウム、塩素イオン等のイオン化された水
中溶存塩類、硬度成分は80〜99％程度の高高率で除去さ
れる。しかし水中に溶存する酸素、窒素、炭酸ガス等の
ガス類は半透膜で殆ど除去されることなく膜の透過水側
に通り抜ける。(Prior Art) When water is treated by a reverse osmosis device using a semipermeable membrane, ionized dissolved salts in water such as calcium, sodium, and chloride ions, and hardness components are removed at a high rate of about 80 to 99%. It However, gases such as oxygen, nitrogen, carbon dioxide, etc. dissolved in water pass through the permeate side of the membrane without being removed by the semipermeable membrane.
この透過水中の溶存炭酸ガスを減じて後続のイオン交換
装置の負担となることを少くするため、あるいは透過水
のPHを調整することを目的として、逆浸透装置による処
理前または後に空気吹込み式の充填塔すなわち脱炭酸塔
装置を併設して脱炭酸処理することが一般に行われてい
る。In order to reduce the carbon dioxide gas dissolved in this permeate to lessen the burden on the subsequent ion exchange device, or to adjust the pH of the permeate, an air-blown type before or after treatment with the reverse osmosis device. It is generally practiced to install a packed tower, that is, a decarboxylation tower device for decarbonation.
（発明が解決しようとする問題点） 従来技術による逆浸透装置に組合わせる脱炭酸塔による
水中溶存炭酸ガスの除去方法は、空気吹込み方式のた
め、空気中に通常300ppm程度含まれている炭酸ガスの分
圧により水中溶存炭酸ガスを精々2mg/、普通には5mg/
の残存濃度になる程度までしか除去できない。この除
去残の炭酸ガスはそのまま後続のイオン交換装置に対す
る負担となる。(Problems to be solved by the invention) The method of removing dissolved carbon dioxide gas in water by the decarbonation tower combined with the reverse osmosis device according to the prior art is the air blowing method, and therefore the carbon dioxide contained in the air is usually about 300 ppm. Dissolved carbon dioxide in water at best 2 mg /, usually 5 mg / depending on the partial pressure of the gas
Can be removed only to the extent that the residual concentration of The carbon dioxide gas remaining after this removal directly imposes a burden on the ion exchange device.
本発明は従来技術の上記問題点を解決し、逆浸透処理後
にイオン交換処理を行う純水製造装置において、イオン
の交換処理に先立つて水中溶存炭酸ガスの高率除去を行
うことを可能とする方法を提供することを目的とする。INDUSTRIAL APPLICABILITY The present invention solves the above-mentioned problems of the prior art, and enables a high-purity removal of dissolved carbon dioxide gas in water prior to the ion exchange treatment in a pure water production apparatus that performs ion exchange treatment after reverse osmosis treatment. The purpose is to provide a method.
（問題点を解決するための手段） 前記目的は、本発明方法により、逆浸透装置を２段階に
分け、第１段階では炭酸ガスの透過を許容し、第２段階
ではPH風整により溶存炭酸ガスをイオン態に変換して逆
浸透処理して除去することにより達成される。(Means for Solving Problems) According to the method of the present invention, the purpose is to divide the reverse osmosis apparatus into two stages, permitting permeation of carbon dioxide gas in the first stage, and dissolving carbon dioxide in the second stage by PH adjustment This is achieved by converting the gas to an ionic state and removing it by reverse osmosis.
すなわち、本発明の純水製造装置における溶存炭酸ガス
の除去方法は、構成としては、遊離炭酸ガスを含む原水
を逆浸透処理したのちイオン交換処理して純水を製造す
る装置において、逆浸透処理の第１段階目に原水中の硬
度成分を高率にて除去する逆浸透装置を用いて処理し、
その透過水にアルカリ剤を加えてPHをアルカリ側にし、
さらに必要な場合極く少量のスケール防止剤を配加し、
かくして重炭酸イオンおよび炭酸イオンに変化させた炭
酸ガス成分を第２段階目の逆浸透装置を用いて除去する
処理を行うことを特徴とする。That is, the method for removing dissolved carbon dioxide gas in the pure water producing apparatus of the present invention has a structure in which reverse osmosis treatment is performed in an apparatus for producing pure water by reverse osmosis treatment of raw water containing free carbon dioxide gas and then ion exchange treatment. In the first stage of the treatment with a reverse osmosis device that removes hardness components in raw water at a high rate,
An alkaline agent is added to the permeated water to make PH alkaline,
If necessary, add a very small amount of scale inhibitor,
Thus, it is characterized in that the carbon dioxide gas component converted into bicarbonate ions and carbonate ions is removed using the second stage reverse osmosis device.
（作用） 本発明方法によると、遊離炭酸ガスを含む原水は少量の
硫酸、塩酸等の添加により弱酸性として先づ第１段階逆
浸透装置で、炭酸カルシウム等のスケール析出を防止し
ながら一般塩類、硬度成分等が高率で除去される。この
透過水は硬度成分が相対的に少いものとなる。またこの
段階では溶存炭酸ガスについて第１段階逆浸透処理の前
または後で空気吹込み方式の脱炭酸塔で処理して炭酸ガ
ス成分ができるだけ除去されるようにするのがよい。(Operation) According to the method of the present invention, the raw water containing free carbon dioxide is weakly acid by the addition of a small amount of sulfuric acid, hydrochloric acid or the like, and is first treated with the first-stage reverse osmosis device while preventing the precipitation of scales such as calcium carbonate and general salts. , Hardness components, etc. are removed at a high rate. The permeated water has a relatively small hardness component. At this stage, the dissolved carbon dioxide gas is preferably treated in an air blowing type decarbonation tower before or after the first-stage reverse osmosis treatment so that carbon dioxide gas components are removed as much as possible.
次に第１段階逆浸透装置の透過水に苛性ソーダ等のアル
カリ剤を添加しPHを弱アルカリ性とし、例えばPHを8.5
以上とすることにより、ガス態として水中に溶存してい
た炭酸ガスは重炭酸イオン（HCO3 -）または炭酸イオン
（CO3 --）に変換されてイオン状態となる。これを第２
段階逆浸透装置で処理すれば、前記の炭酸ガス成分は他
のイオンと同様に90％以上の高い除去率で除去される。
従つて後工程のイオン交換処理装置に対する炭酸ガスの
負担は著しく減じられる。第２段階逆浸透装置は、東レ
（株）製品番SU−400R、デユポン社製品番Ｂ−９、Ｂ−
15等の合成膜で高いPHに適用でき、しかも高い塩排除率
を持つものを使用すれば有効である。この第２段階逆浸
透処理においては、入口水の第１段階逆浸透処理の透過
水は硬度成分がよく除去されているためにPHを上げても
炭酸カルシウム等の析出は起り難くなつているが、アル
カリ剤を添加する他、必要に応じて極く少量のポリリン
酸塩等のスケール防止剤を加えて第２段階逆浸透処理を
行えば、スケール析出の防止に一層有効となる。Next, an alkaline agent such as caustic soda is added to the permeated water of the first stage reverse osmosis unit to make the pH weakly alkaline, and for example, the pH is adjusted to 8.5
With more, the carbon dioxide gas that has been dissolved in the water as a gas state bicarbonate ion (HCO 3 -) or carbonate ions (CO 3 -) to be converted the ionic state. This is the second
When treated with the stepwise reverse osmosis device, the carbon dioxide gas component is removed at a high removal rate of 90% or more like other ions.
Therefore, the burden of carbon dioxide gas on the ion exchange treatment device in the subsequent step is significantly reduced. The second stage reverse osmosis device is Toray Industries, Ltd. product number SU-400R, Dyupon Co. product number B-9, B-
It is effective to use a synthetic membrane such as 15 which can be applied to high PH and has a high salt removal rate. In this second-stage reverse osmosis treatment, since the hardness component of the permeated water of the first-stage reverse osmosis treatment of the inlet water is well removed, precipitation of calcium carbonate and the like is less likely to occur even if the pH is increased. In addition to the addition of the alkaline agent, if necessary, a very small amount of a scale inhibitor such as polyphosphate is added to carry out the second stage reverse osmosis treatment, which is more effective in preventing scale precipitation.
（実施例） 次に本発明方法を添付図を参照し実施例に即して具体的
に説明する。添付図は本発明方法を実施するフローの１
例を示す。(Example) Next, the method of the present invention will be specifically described with reference to the accompanying drawings. The attached drawing is one of the flow for carrying out the method of the present invention.
Here is an example:
原水（１）は予め凝集沈澱法、濾過法等の通常水処理を
施して懸濁固形物を充分に除去した清浄水とし、固形物
が逆浸透装置の半透膜の目づまり原因となることを予防
する。Raw water (1) is purified water that has been subjected to normal water treatment such as coagulation sedimentation method and filtration method to sufficiently remove suspended solids, and the solids cause clogging of the semipermeable membrane of the reverse osmosis device. Prevent.
この原水（１）は原水槽（２）に受入れられ、原水ポン
プ（３）により加圧送出され、カートリツジフイルター
（４）を通つて精密濾過され、昇圧ポンプ（５）により
逆浸透圧力に昇圧されて第１段階逆浸透装置（６）に向
つて送られる。この送水系のカートリツジフイルター
（４）前に硫酸、塩酸等の酸を酸貯槽（７）から注入ポ
ンプ（８）により注入して、原水を弱酸性に調整した上
で逆浸透装置（６）で第１段階逆浸透処理する。This raw water (1) is received in a raw water tank (2), pressurized and sent by a raw water pump (3), microfiltered through a cartridge spring filter (4), and boosted to a reverse osmotic pressure by a boost pump (5). It is then sent to the first stage reverse osmosis device (6). An acid such as sulfuric acid or hydrochloric acid is injected from an acid storage tank (7) by an injection pump (8) before the cartridge filter (4) of the water supply system to adjust the raw water to be weakly acidic, and then the reverse osmosis device (6). The first stage reverse osmosis treatment is carried out.
逆浸透装置（６）より一般塩類、硬度成分を高率に除去
された透過水（９）は一旦脱炭酸塔（10）に送られ、ま
た塩類が濃縮される側の原水は過大な濃縮を防止するた
め一部ブロー水（11）として逆浸透装置（６）から放出
される。The permeated water (9) from which general salts and hardness components have been removed by the reverse osmosis device (6) at a high rate is once sent to the decarbonation tower (10), and the raw water on the salt concentration side is excessively concentrated. In order to prevent it, a part of blown water (11) is discharged from the reverse osmosis device (6).
脱炭酸塔（10）は充填層（12）を持ち前記の透過水
（９）が充填層（12）内を流下する間にブロアー（13）
から吹き込まれ上昇する新鮮な空気と向流接触すること
により炭酸ガスが除去され脱炭酸水（14）となつて塔底
に貯まる。The decarbonation tower (10) has a packed bed (12) and a blower (13) while the permeated water (9) flows down in the packed bed (12).
The carbon dioxide gas is removed by making countercurrent contact with the fresh air that is blown from and rises, and is stored in the bottom of the column as decarbonated water (14).
次にこの脱炭酸水の送水系には第２段階逆浸透処理のた
め苛性ソーダ等のアルカリ剤をアルカリ貯槽（15）から
注入ポンプ（16）により注入してPHを8.5前後に調整し
て残る溶存炭酸ガスを重炭酸イオンおよび炭酸イオンに
変化させ、またポリリン酸塩等のスケール防止剤の少量
を、その貯槽（17）から注入ポンプ（18）により配加
し、こうして調整された水を加圧ポンプ（19）により逆
浸透圧力に昇圧させて第２段階逆浸透装置（20）に送つ
て第２段階逆浸透処理する。Next, for the second-stage reverse osmosis treatment, an alkaline agent such as caustic soda is injected from the alkali storage tank (15) by the injection pump (16) into the water supply system of this decarbonated water, and the pH is adjusted to around 8.5 to remain dissolved. Carbon dioxide is changed to bicarbonate and carbonate ions, and a small amount of scale inhibitor such as polyphosphate is added from its storage tank (17) by an injection pump (18) to pressurize the water thus adjusted. The reverse osmosis pressure is increased by the pump (19) and is sent to the second-stage reverse osmosis device (20) for the second-stage reverse osmosis treatment.
逆浸透装置（20）より重炭酸イオン、炭酸イオンが除去
された透過水（21）は次のイオン交換塔（22）に送つて
イオン交換処理する。The permeated water (21) from which bicarbonate ions and carbonate ions have been removed from the reverse osmosis device (20) is sent to the next ion exchange tower (22) for ion exchange treatment.
生じたイオン交換処理水（23）は純水として処理水槽
（24）に貯められ、そこから目的用途に供給される。The generated ion-exchange treated water (23) is stored in the treated water tank (24) as pure water and supplied from there to the intended use.
逆浸透装置（20）からも塩の濃縮を防止するために一定
水量のブロー水（25）が放出される。The reverse osmosis device (20) also discharges a fixed amount of blow water (25) to prevent the concentration of salt.
以下、本発明方法の実施例を数値により示す。図示フロ
ーの装置を使用して実施した例である。その操作の概要
は次のとおりである。In the following, numerical examples of the method of the present invention will be shown. It is an example implemented using the apparatus of the illustrated flow. The outline of the operation is as follows.
先づ原水に硫酸を注入しPHを下げ重炭酸イオン等を炭酸
ガスに変換するとともにスケール析出を防止しながら第
１段階逆浸透装置にて処理する。この透過水を脱炭酸塔
にて炭酸ガスをできるだけ除去する。こうして得られた
脱炭酸水は水中に僅かの硬度成分と空気中炭酸ガス分圧
との平衡量程度の炭酸ガスを含む。First, sulfuric acid is injected into the raw water to lower the pH, convert bicarbonate ions and the like into carbon dioxide, and treat with the first stage reverse osmosis device while preventing scale deposition. This permeated water is subjected to a carbon dioxide removal tower to remove carbon dioxide gas as much as possible. The decarbonated water thus obtained contains a slight hardness component and carbon dioxide in an amount of equilibrium with the partial pressure of carbon dioxide in the air.
これに苛性ソーダと少量のポリリン酸塩を注入しPHを8.
5程度に調整し炭酸ガスを重炭酸イオンおよび炭酸イオ
ンに変換し第２段階逆浸透装置にて処理する。第２段階
逆浸透装置の透過水は、この装置の入口側で炭酸ガスが
重炭酸ガスンおよび炭酸イオンに変換されているためこ
れらがイオンとして高い除去率で除去され、後続のイオ
ン交換装置に対する炭酸ガス成分の負担が軽減される。Inject caustic soda and a small amount of polyphosphate into this to adjust the pH to 8.
Adjust to about 5 to convert carbon dioxide into bicarbonate and carbonate ions and treat with a second stage reverse osmosis device. The permeated water of the second-stage reverse osmosis device has carbon dioxide gas converted into bicarbonate gas and carbonate ions at the inlet side of this device, so these are removed as ions at a high removal rate, and the carbon dioxide for the subsequent ion exchange device is removed. The burden of gas components is reduced.
図中、符号（Ａ）（Ｂ）（Ｃ）（Ｄ）（Ｅ）（Ｆ）で指
摘の各経過点における水質分析値を次表に示す。表の水
質数値の単位はすべてppm CaCO3である。PHは25℃の値
である。比較のため、本発明と異り第２段階逆浸透処理
前に苛性ソーダ、ポリリン酸塩の注入を行わずに脱炭酸
塔出口水を直接第２段階逆浸透装置で処理した場合の処
理水の水質数値を最終列に併記した。The following table shows the water quality analysis values at each progress point indicated by the reference signs (A), (B), (C), (D), (E), and (F) in the figure. All units of water quality in the table are ppm CaCO 3 . PH is a value at 25 ° C. For comparison, unlike the present invention, the water quality of the treated water when the decarbonation tower outlet water is directly treated by the second stage reverse osmosis device without injecting caustic soda and polyphosphate before the second stage reverse osmosis treatment. The numerical values are also shown in the last column.
（発明の効果） 本発明方法によると、遊離炭酸ガスを含む原水を逆浸透
処理したのちイオン交換処理して純水を製造する装置に
おいて、溶存炭酸ガスを逆浸透装置により高率で除去し
て、後続のイオン交換塔に対する負荷アニオン交換量を
比較方法の場合の7.6ppm CaCO3から2.0ppm CaCO3にすな
わち26.3％に効果的に低減することができる。 (Effect of the Invention) According to the method of the present invention, in a device for producing pure water by subjecting raw water containing free carbon dioxide to reverse osmosis and then ion exchange treatment, dissolved carbon dioxide is removed at a high rate by a reverse osmosis device. , it can be effectively reduced from 7.6 ppm CaCO 3 in the case of comparison methods load anion exchange capacity for a subsequent ion exchange column to 2.0 ppm CaCO 3 in other words 26.3%.
添付図は本発明方法を実施するフローの１例を示す図で
ある。 （１）……原水、（２）……原水槽、（３）……原水ポ
ンプ、（４）……カートリツジフイルター、（５）……
昇圧ポンプ、（６）……第１段階逆浸透装置、（７）…
…酸貯槽、（８）……注入ポンプ、（９）……透過水、
（10）……脱炭酸塔、（11）……ブロー水、（12）……
充填層、（13）……ブロアー、（14）……脱炭酸水、
（15）……アルカリ貯槽、（16）……注入ポンプ、（1
7）……貯槽、（18）……注入ポンプ、（19）……加圧
ポンプ、（20）……第２段階逆浸透装置、（21）……透
過水、（22）……イオン交換塔、（23）……イオン交換
処理水、（24）……処理水槽、（25）……ブロー水。The attached drawing is a diagram showing an example of a flow for carrying out the method of the present invention. (1) …… Raw water, (2) …… Raw water tank, (3) …… Raw water pump, (4) …… Cartridge ridge filter, (5) ……
Step-up pump, (6) ... First stage reverse osmosis device, (7) ...
… Acid storage tank, (8) …… injection pump, (9) …… permeate,
(10) …… Decarbonation tower, (11) …… Blow water, (12) ……
Packed bed, (13) …… Blower, (14) …… Decarbonated water,
(15) …… Alkaline storage tank, (16) …… Injection pump, (1
7) ... storage tank, (18) ... injection pump, (19) ... pressurizing pump, (20) ... second stage reverse osmosis device, (21) ... permeate, (22) ... ion exchange Tower, (23) …… ion exchange treated water, (24) …… treated water tank, (25) …… blow water.
Claims (1)
のちイオン交換処理して純水を製造する装置において、
逆浸透処理の第１段階目に原水中の硬度成分を高率にて
除去する逆浸透装置を用いて処理し、その透過水にアル
カリ剤を加えてPHをアルカリ側にし、さらに必要な場合
極く少量のスケール防止剤を配加し、かくして重炭酸イ
オンおよび炭酸イオンに変化させた炭酸ガス成分を第２
段階目の逆浸透装置を用いて除去する処理を行うことを
特徴とする純水製造装置における溶存炭酸ガスの除去方
法。1. An apparatus for producing pure water by subjecting raw water containing free carbon dioxide gas to reverse osmosis followed by ion exchange treatment,
In the first stage of reverse osmosis treatment, the raw water is treated with a reverse osmosis device that removes hardness components at a high rate, and an alkaline agent is added to the permeated water to make PH alkaline, and if necessary, A small amount of scale inhibitor was added, and the carbon dioxide gas component thus converted into bicarbonate ion and carbonate ion was added to the second
A method for removing dissolved carbon dioxide gas in a pure water producing apparatus, which comprises performing a removal treatment using a reverse osmosis apparatus at a stage.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61172135A JPH0790215B2 (en) | 1986-07-21 | 1986-07-21 | Method for removing dissolved carbon dioxide gas in pure water production equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61172135A JPH0790215B2 (en) | 1986-07-21 | 1986-07-21 | Method for removing dissolved carbon dioxide gas in pure water production equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6328486A JPS6328486A (en) | 1988-02-06 |
| JPH0790215B2 true JPH0790215B2 (en) | 1995-10-04 |
Family
ID=15936215
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61172135A Expired - Lifetime JPH0790215B2 (en) | 1986-07-21 | 1986-07-21 | Method for removing dissolved carbon dioxide gas in pure water production equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0790215B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20110137354A (en) * | 2009-03-09 | 2011-12-22 | 두산중공업 주식회사 | System and method for using carbon dioxide sequestered from seawater in the remineralization of process water |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0649190B2 (en) * | 1986-07-28 | 1994-06-29 | 栗田工業株式会社 | High-purity water manufacturing equipment |
| JPH0649191B2 (en) * | 1988-03-14 | 1994-06-29 | オルガノ株式会社 | Two-stage reverse osmosis membrane treatment method |
| JP5130618B2 (en) * | 2005-10-25 | 2013-01-30 | 栗田工業株式会社 | Method and apparatus for treating wastewater containing carbonic acid and ammonia |
| JP2013022521A (en) * | 2011-07-21 | 2013-02-04 | Jfe Steel Corp | Pure water producing facility and method of elongating service life of ion-exchange resin |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS614591A (en) * | 1984-06-04 | 1986-01-10 | アローヘツド、インダストリアル、ウオーター、インコーポレイテツド | Reverse osmosis system |
| JPS62110795A (en) * | 1985-11-06 | 1987-05-21 | Kurita Water Ind Ltd | Device for producing high-purity water |
-
1986
- 1986-07-21 JP JP61172135A patent/JPH0790215B2/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS614591A (en) * | 1984-06-04 | 1986-01-10 | アローヘツド、インダストリアル、ウオーター、インコーポレイテツド | Reverse osmosis system |
| JPS62110795A (en) * | 1985-11-06 | 1987-05-21 | Kurita Water Ind Ltd | Device for producing high-purity water |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20110137354A (en) * | 2009-03-09 | 2011-12-22 | 두산중공업 주식회사 | System and method for using carbon dioxide sequestered from seawater in the remineralization of process water |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6328486A (en) | 1988-02-06 |
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