JP3278918B2 - Desalting method - Google Patents
Desalting methodInfo
- Publication number
- JP3278918B2 JP3278918B2 JP22290692A JP22290692A JP3278918B2 JP 3278918 B2 JP3278918 B2 JP 3278918B2 JP 22290692 A JP22290692 A JP 22290692A JP 22290692 A JP22290692 A JP 22290692A JP 3278918 B2 JP3278918 B2 JP 3278918B2
- Authority
- JP
- Japan
- Prior art keywords
- water
- treated
- membrane separation
- softener
- separation device
- 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
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A20/00—Water conservation; Efficient water supply; Efficient water use
- Y02A20/124—Water desalination
- Y02A20/131—Reverse-osmosis
Landscapes
- Treatment Of Water By Ion Exchange (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は脱塩方法に係り、特に、
被処理水を逆浸透（ＲＯ）膜分離装置で処理して脱塩す
る方法において、ＲＯ膜分離装置の透過水量の低下を防
止して、高水質の処理水を容易かつ効率的に得る脱塩方
法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a desalination method,
In a method of treating a water to be treated with a reverse osmosis (RO) membrane separation device to desalinate, a desalination method for easily and efficiently obtaining a high-quality treated water by preventing a decrease in a permeated water amount of the RO membrane separation device About the method.
【０００２】[0002]
【従来の技術】従来、市水の脱塩方法としては、まず、
市水に亜硫酸水素ナトリウム（ＮａＨＳＯ3 ）を添加し
て脱塩素処理し、次いで、水酸化ナトリウム（ＮａＯ
Ｈ）等のアルカリ剤を添加してｐＨ８〜９に調整してＲ
Ｏ膜分離装置で脱分離処理する方法が採用されている。2. Description of the Related Art Conventionally, as a desalination method of city water, first,
Sodium bisulfite (NaHSO 3 ) is added to city water for dechlorination, and then sodium hydroxide (NaO
H) to adjust the pH to 8-9 by adding an alkaline agent
A method of performing de-separation treatment with an O membrane separation device is employed.
【０００３】なお、ここで、ＲＯ膜分離装置の流入水を
アルカリ剤でｐＨ８〜９に調整するのは、流入水中の炭
酸成分の除去性を高め、透過水水質を向上させるためで
ある。[0003] Here, the reason why the inflow water of the RO membrane separation apparatus is adjusted to pH 8 to 9 with an alkaline agent is to enhance the removability of a carbonic acid component in the inflow water and improve the quality of permeated water.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、脱塩素
処理水にアルカリ剤を添加してｐＨ８〜９に調整すると
カルシウム、アルミニウム、鉄などの金属成分に起因す
るスケールが発生し、これがＲＯ膜分離装置のＲＯ膜を
汚染して透過水量の低下を引き起こす。However, when the pH of the dechlorinated water is adjusted to 8 to 9 by adding an alkaline agent to the dechlorinated water, scales resulting from metal components such as calcium, aluminum and iron are generated, and this is caused by the RO membrane separation apparatus. And contaminate the RO membrane, causing a decrease in the amount of permeated water.
【０００５】このようなスケールの原因となる金属成分
を除去するために、軟化器を用い、脱塩素処理水を軟化
器に通水して、金属成分を硬度成分と共に除去した後、
ＲＯ膜分離装置に通水する方法も考えられる。しかしな
がら、この場合においても、ＲＯ膜分離装置の透過水量
は経時的に低下する。[0005] In order to remove a metal component causing such a scale, a softener is used to pass dechlorinated water through the softener to remove the metal component together with the hardness component.
A method of passing water through an RO membrane separation device is also conceivable. However, also in this case, the permeated water amount of the RO membrane separation device decreases with time.
【０００６】本発明は上記従来の問題点を解決し、市水
等の被処理水をＲＯ膜分離装置で処理して脱塩する方法
において、ＲＯ膜分離装置の透過水量の安定化、透過水
水質の向上を図り、高水質の脱塩処理水を容易かつ効率
的に得ることができる脱塩方法を提供することを目的と
する。SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems and provides a method for desalinating treated water such as city water using an RO membrane separation apparatus. An object of the present invention is to provide a desalination method capable of improving water quality and easily and efficiently obtaining high-quality desalinated water.
【０００７】[0007]
【課題を解決するための手段】本発明の脱塩方法は、被
処理水に酸を添加してｐＨ５以下に調整して軟化器で処
理した後、該軟化処理水をｐＨ８以上に調整してＲＯ膜
分離装置で処理することを特徴とする。In the desalting method of the present invention, an acid is added to water to be treated, adjusted to pH 5 or less, and treated with a softener, and then the softened water is adjusted to pH 8 or more. It is characterized in that it is processed by an RO membrane separation device.
【０００８】[0008]
【作用】被処理水のｐＨ調整を行なわずに、通常ｐＨ６
〜８の被処理水を軟化器に通水しても、この水中に含有
されるカチオン性のイオン状の金属成分は硬度成分と共
に除去されるが、非カチオン性ないし非イオン性の金属
成分を除去することはできない。このため、軟化器を通
過した後も、このような金属成分がなお残留することと
なり、後段のＲＯ膜分離装置において、膜汚染による透
過水量の経時的低下を引き起こす。The pH of the water to be treated is usually adjusted to 6 without adjusting the pH.
When the water to be treated is passed through a softener, the cationic ionic metal component contained in the water is removed together with the hardness component, but the non-cationic or non-ionic metal component is removed. It cannot be removed. For this reason, even after passing through the softener, such a metal component still remains, causing a temporal decrease in the amount of permeated water due to membrane contamination in a subsequent RO membrane separation apparatus.
【０００９】これに対して、軟化器への通水に先立ち、
予め被処理水に酸を添加してｐＨ５以下に調整すること
により、被処理水中に含有されている非カチオン性或い
は非イオン性の金属成分（アルミニウム、鉄など）がカ
チオン性のイオン状となり、これらも軟化器により硬度
成分と共に効率的に除去される。[0009] On the other hand, prior to passing water through the softener,
By adding an acid to the water to be treated in advance to adjust the pH to 5 or less, the non-cationic or non-ionic metal components (aluminum, iron, etc.) contained in the water to be treated become cationic ionic, These are also efficiently removed together with the hardness component by the softener.
【００１０】このため、後段のＲＯ膜分離装置における
膜汚染及び膜汚染による透過水量の低下は有効に防止さ
れる。[0010] For this reason, membrane contamination in the RO membrane separation device at the subsequent stage and a decrease in the amount of permeated water due to membrane contamination are effectively prevented.
【００１１】しかして、軟化器の処理水をｐＨ８以上に
調整してＲＯ膜分離装置に通水するため、水中の炭酸成
分が効率的に除去され、透過水水質が向上する。However, since the treated water of the softener is adjusted to pH 8 or more and passed through the RO membrane separation device, the carbonic acid component in the water is efficiently removed, and the quality of the permeated water is improved.
【００１２】[0012]
【実施例】以下、図面を参照して本発明を詳細に説明す
る。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings.
【００１３】図１は本発明の脱塩方法の一実施例を示す
系統図である。FIG. 1 is a system diagram showing one embodiment of the desalting method of the present invention.
【００１４】図示の如く、本発明においては、市水等の
被処理水を配管１１より軟化器１に導入するにあたり、
まず、脱塩素処理のためのＮａＨＳＯ3 を配管１２より
添加し、更に、ｐＨ調整のための硫酸（Ｈ2 ＳＯ4 ）、
塩酸（ＨＣｌ）等の酸を配管１３より添加してｐＨ５以
下、好ましくはｐＨ５．０〜４．０に調整する。軟化器
１に導入された被処理水は、含有される金属成分がカチ
オン性のイオン状となっているため、これらが硬度成分
と共に効率的に除去される。As shown in the figure, according to the present invention, when water to be treated such as city water is introduced into a softener 1 through a pipe 11,
First, NaHSO 3 for dechlorination is added from the pipe 12, and further, sulfuric acid (H 2 SO 4 ) for pH adjustment,
An acid such as hydrochloric acid (HCl) is added through a pipe 13 to adjust the pH to 5 or less, preferably to 5.0 to 4.0. Since the metal components contained in the water to be treated introduced into the softener 1 are in the form of cationic ions, they are efficiently removed together with the hardness components.
【００１５】軟化器１の流出水は、次いで、ポンプＰを
備える配管１４より第１のＲＯ膜分離装置２に導入され
て膜分離処理される。なお、この配管１４において、Ｎ
ａＯＨ等のアルカリ剤が配管１５より添加され、第１の
ＲＯ膜分離装置２への流入水のｐＨは８以上、好ましく
はｐＨ８〜９に調整される。第１のＲＯ膜分離装置２の
濃縮水は配管１６より排出されると共に透過水は配管１
７より第２のＲＯ膜分離装置３に導入されて更に膜分離
処理され、濃縮水は配管１８より排出されると共に、透
過水は処理水として、配管１９より系外へ排出される。Next, the effluent from the softener 1 is introduced into the first RO membrane separator 2 through a pipe 14 provided with a pump P, and subjected to membrane separation. In this piping 14, N
An alkaline agent such as aOH is added through the pipe 15, and the pH of the water flowing into the first RO membrane separation device 2 is adjusted to 8 or more, preferably to pH 8 to 9. The concentrated water of the first RO membrane separation device 2 is discharged from the pipe 16 and the permeated water is discharged from the pipe 1
7, the water is introduced into the second RO membrane separation device 3 and further subjected to membrane separation processing, and the concentrated water is discharged from the pipe 18 and the permeated water is discharged from the pipe 19 as treated water to the outside of the system.
【００１６】このような処理系統においては、軟化器を
使用しているため、再生剤としてはＮａＣｌ等を用いる
ことができる。このため、Ｈ型のカチオン交換塔の場合
のように酸性廃液が発生しないため、取り扱いが容易と
なる。In such a processing system, since a softener is used, NaCl or the like can be used as a regenerant. For this reason, unlike the case of the H-type cation exchange column, no acidic waste liquid is generated, so that the handling becomes easy.
【００１７】以下に実験例を挙げて、本発明をより具体
的に説明する。Hereinafter, the present invention will be described more specifically with reference to experimental examples.
【００１８】実験例１ 図１に示す方法で処理を行なった。下記水質の厚木市水
にＮａＨＳＯ3 を添加して脱塩素処理した後、Ｈ2 ＳＯ
4 を添加してｐＨ５に調整した。次にこの処理水を軟化
器（レバチットＭＰ５００，Ｎａ型）に通水し、この濾
過水にＮａＯＨを添加してｐＨ８〜９に調整し、第１及
び第２のＲＯ膜分離装置に通水した。なお、軟化器の通
水ＳＶ＝３０とし、再生はＮａＣｌで行なった。また、
ＲＯ膜分離装置は入口圧力２５ｋｇｆ／ｃｍ2 、水温２
５〜２７℃、給水量２．５ｍ3 ／ｈ、水回収率は７５％
（第１のＲＯ膜分離装置）とした。Experimental Example 1 Processing was performed by the method shown in FIG. After adding NaHSO 3 to Atsugi-shi water of the following water quality and dechlorinating it, H 2 SO
4 was added to adjust the pH to 5. Next, the treated water was passed through a softener (Levatit MP500, Na type), and NaOH was added to the filtered water to adjust the pH to 8 to 9, and then passed through the first and second RO membrane separation devices. . The water flow through the softener was set to SV = 30, and the regeneration was performed with NaCl. Also,
RO membrane separator has an inlet pressure of 25 kgf / cm 2 and a water temperature of 2
5-27 ° C, water supply 2.5m 3 / h, water recovery rate 75%
(First RO membrane separation device).
【００１９】厚木市水水質 電導率（μｓ／ｍ）：２００ ｐＨ（−） ：７．８ Ｃａ（ｍｇ／ｌ） ：１５ Ｍｇ（ｍｇ／ｌ） ：６ Ａｌ（ｍｇ／ｌ） ：０．０８ Ｍ−アルカリ度（ｍｇ／ｌ（ＣａＣＯ3 として））：４
０ シリカ（ｍｇ／ｌ）：２８ その結果、図２に示す如く、運転５００時間後において
も第１のＲＯ膜分離装置の透過水量の低下はなく、安定
した透過水量にて高水質の透過水が得られた。 Atsugi city water conductivity (μs / m): 200 pH (-): 7.8 Ca (mg / l): 15 Mg (mg / l): 6 Al (mg / l): 0.08 M-alkalinity (mg / l (as CaCO 3 )): 4
0 Silica (mg / l): 28 As a result, as shown in FIG. 2, even after 500 hours of operation, there was no decrease in the amount of permeated water of the first RO membrane separation device, and the permeated water of high water quality was maintained at a stable amount of permeated water. was gotten.
【００２０】実験例２（比較例） Ｈ2 ＳＯ4 の添加及び軟化器での処理を行なわず、脱塩
素処理水をそのままＲＯ膜分離装置に供給したこと以外
は実験例１と同様にして行なった。その結果、図３に示
す如く、第１のＲＯ膜分離装置の透過水量は経時的に大
きく低下した。Experimental Example 2 (Comparative Example) The same operation as in Experimental Example 1 was carried out except that the dechlorinated water was directly supplied to the RO membrane separation apparatus without adding H 2 SO 4 and treating with a softener. Was. As a result, as shown in FIG. 3, the amount of permeated water of the first RO membrane separation device decreased significantly with time.
【００２１】実験例３（比較例） Ｈ2 ＳＯ4 の添加を行なわず、脱塩素処理水をそのまま
軟化器に供給したこと以外は実験例１と同様にして行な
った。その結果、図４に示す如く、第１のＲＯ膜分離装
置の透過水量の低下は実験例２の場合よりも少ないもの
の、やはり経時的に低下した。Experimental Example 3 (Comparative Example) The experiment was performed in the same manner as in Experimental Example 1 except that H 2 SO 4 was not added and dechlorinated water was directly supplied to a softener. As a result, as shown in FIG. 4, although the decrease in the amount of permeated water in the first RO membrane separation device was smaller than in the case of Experimental Example 2, it also decreased with time.
【００２２】[0022]
【発明の効果】以上詳述した通り、本発明の脱塩方法に
よれば、市水等の被処理水をＲＯ膜分離装置を用いて脱
塩処理するにあたり、ＲＯ膜分離装置の膜汚染及び膜汚
染に起因する透過水量の低下を防止して、高水質の処理
水を、安定かつ効率的に得ることが可能とされる。As described in detail above, according to the desalination method of the present invention, when the water to be treated, such as city water, is desalinated by using the RO membrane separation apparatus, the membrane contamination of the RO membrane separation apparatus is reduced. It is possible to prevent a decrease in the amount of permeated water due to membrane contamination and to obtain high-quality treated water stably and efficiently.
【図１】本発明の脱塩方法の一実施例を示す系統図であ
る。FIG. 1 is a system diagram showing one embodiment of the desalination method of the present invention.
【図２】実験例１の結果を示すグラフである。FIG. 2 is a graph showing the results of Experimental Example 1.
【図３】実験例２の結果を示すグラフである。FIG. 3 is a graph showing the results of Experimental Example 2.
【図４】実験例３の結果を示すグラフである。FIG. 4 is a graph showing the results of Experimental Example 3.
１ 軟化器 ２ 第１のＲＯ膜分離装置 ３ 第２のＲＯ膜分離装置 DESCRIPTION OF SYMBOLS 1 Softener 2 1st RO membrane separation apparatus 3 2nd RO membrane separation apparatus
Claims (2)
整して軟化器で処理した後、該軟化処理水をｐＨ８以上
に調整して逆浸透膜分離装置で処理することを特徴とす
る脱塩方法。The method is characterized in that an acid is added to the water to be treated to adjust the pH to 5 or less and then treated with a softener, and then the softened water is adjusted to a pH of 8 or more and treated with a reverse osmosis membrane separator. Desalination method.
素ナトリウムを添加すると共に、酸を添加してｐＨ５以
下に調整して軟化器で処理することを特徴とする脱塩方
法。 2. The method according to claim 1, wherein the water to be treated is a sulfite solution.
At the same time as adding sodium hydrogen, add acid and add
Desalination method characterized by adjusting below and treating with a softener
Law.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22290692A JP3278918B2 (en) | 1992-08-21 | 1992-08-21 | Desalting method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22290692A JP3278918B2 (en) | 1992-08-21 | 1992-08-21 | Desalting method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0663549A JPH0663549A (en) | 1994-03-08 |
| JP3278918B2 true JP3278918B2 (en) | 2002-04-30 |
Family
ID=16789722
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22290692A Expired - Fee Related JP3278918B2 (en) | 1992-08-21 | 1992-08-21 | Desalting method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3278918B2 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6398965B1 (en) | 1998-03-31 | 2002-06-04 | United States Filter Corporation | Water treatment system and process |
| US7320756B2 (en) | 2001-05-05 | 2008-01-22 | Debasish Mukhopadhyay | Method and apparatus for treatment of feedwaters by membrane separation under acidic conditions |
| JP5055662B2 (en) * | 2001-05-11 | 2012-10-24 | 栗田工業株式会社 | Ultrapure water production apparatus and ultrapure water production method |
| WO2008090854A1 (en) | 2007-01-24 | 2008-07-31 | Kurita Water Industries Ltd. | Method for the treatment with reverse osmosis membrane |
| JP5729062B2 (en) * | 2011-03-22 | 2015-06-03 | 三浦工業株式会社 | Water treatment method and water treatment system |
| JP5700080B2 (en) * | 2013-07-02 | 2015-04-15 | 栗田工業株式会社 | Method and apparatus for treating waste water containing cationic surfactant |
| JP6609952B2 (en) * | 2015-03-24 | 2019-11-27 | 三菱ケミカルアクア・ソリューションズ株式会社 | Reverse osmosis membrane treatment method |
-
1992
- 1992-08-21 JP JP22290692A patent/JP3278918B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0663549A (en) | 1994-03-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4648307B2 (en) | Continuous electrodeionization apparatus and method | |
| US8119008B2 (en) | Fluid purification methods and devices | |
| US20090039020A1 (en) | Methods for reducing boron concentration in high salinity liquid | |
| JP6764686B2 (en) | Water treatment method and equipment and ion exchange resin regeneration method | |
| EA011830B1 (en) | Method (embodiments) for liquid treatment by reverse osmosis under acidic conditions | |
| JP3646900B2 (en) | Apparatus and method for treating boron-containing water | |
| JPH11244853A (en) | Production of pure water | |
| JP3278918B2 (en) | Desalting method | |
| JP3903746B2 (en) | Circulating cooling water treatment method | |
| JPS62294484A (en) | Reverse osmosis treatment of water containing silica at high concentration | |
| JP3137831B2 (en) | Membrane processing equipment | |
| JPH10272494A (en) | Treatment of organic waste water containing salts of high concentration | |
| CN105948352A (en) | Zero emission recycling process for treating power plant desulfurization high-salinity high-hardness wastewater | |
| JP2000051665A (en) | Desalination method | |
| JP3319053B2 (en) | Treatment method for fluoride-containing water | |
| JP2000070933A (en) | Production of pure water | |
| JP2021007927A (en) | Regeneration process of water softener, and manufacturing apparatus of desalted water | |
| JPH1080684A (en) | Device and method for treating boron-containing water | |
| KR100398417B1 (en) | A method for treating electrogalvanizing wastewaters | |
| JP4208270B2 (en) | Pure water production method | |
| JP2019118891A (en) | Pure water producing apparatus and pure water producing method | |
| JPH11221579A (en) | Treatment of fluorine-containing water | |
| JPH0137997B2 (en) | ||
| JPH10128075A (en) | Reverse osmosis membrane device and treatment using the same | |
| JP2001170658A (en) | Treating device for fluorine-containing waste water and treatment method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080222 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090222 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090222 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100222 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110222 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110222 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120222 Year of fee payment: 10 |
|
| LAPS | Cancellation because of no payment of annual fees |