JPH05247114A - Method for concentrating polycarboxylic acid (salt) solution and continuous concentration method - Google Patents
Method for concentrating polycarboxylic acid (salt) solution and continuous concentration methodInfo
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- JPH05247114A JPH05247114A JP4727492A JP4727492A JPH05247114A JP H05247114 A JPH05247114 A JP H05247114A JP 4727492 A JP4727492 A JP 4727492A JP 4727492 A JP4727492 A JP 4727492A JP H05247114 A JPH05247114 A JP H05247114A
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- solution
- salt
- concentration
- polycarboxylic acid
- concentrating
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】この発明は、ポリカルボン酸
（塩）溶液の濃縮方法および連続濃縮方法に関し、詳し
くは、水処理剤、洗剤ビルダー、分散剤等に利用される
ポリカルボン酸またはポリカルボン酸塩の溶液を、輸送
保管効率の向上のため、あるいは、その利用目的に合わ
せるために、溶液中の溶媒を蒸発除去して濃縮する方
法、および、この濃縮作業を連続的に行う方法に関する
ものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for concentrating a polycarboxylic acid (salt) solution and a method for continuously concentrating the same. More specifically, it relates to a polycarboxylic acid or a polycarboxylic acid used as a water treatment agent, detergent builder, dispersant, etc. A method for concentrating a solution of an acid salt by evaporating and removing the solvent in the solution in order to improve the transportation and storage efficiency or to match the purpose of use, and a method for continuously performing this concentrating operation Is.
【０００２】[0002]
【従来の技術】ポリカルボン酸（塩）は、水処理剤、洗
剤ビルダー、分散剤等の原料として非常に重要なもので
ある。ポリカルボン酸（塩）の製造には、各種の合成方
法や重合方法が適用されるが、通常、製造されたポリカ
ルボン酸（塩）は、水などの溶媒が大量に含まれた溶液
の状態である。2. Description of the Related Art Polycarboxylic acids (salts) are very important as raw materials for water treatment agents, detergent builders, dispersants and the like. Although various synthetic methods and polymerization methods are applied to the production of polycarboxylic acid (salt), normally, the produced polycarboxylic acid (salt) is in the state of a solution containing a large amount of a solvent such as water. Is.
【０００３】水などの溶媒を大量に含んだままでは、輸
送あるいは保管時に嵩が高くなり、輸送保管の効率が悪
くなるため、不経済である。また、ポリカルボン酸
（塩）の使用目的によって、濃度の高いポリカルボン酸
（塩）を用いることが要求される場合も多い。そこて、
製造されたポリカルボン酸（塩）溶液を、輸送保管ある
いは利用に適当な濃度まで濃縮する必要が生じる。If a large amount of a solvent such as water is contained, it becomes uneconomical because it becomes bulky during transportation or storage and the efficiency of transportation and storage deteriorates. Further, depending on the purpose of using the polycarboxylic acid (salt), it is often required to use a polycarboxylic acid (salt) having a high concentration. There
It is necessary to concentrate the produced polycarboxylic acid (salt) solution to a concentration suitable for transport storage or use.
【０００４】従来、ポリカルボン酸（塩）溶液の濃縮方
法としては、大きな容器状の蒸発釜にポリカルボン酸
（塩）溶液を溜め、蒸発釜の外面から加熱して、ポリカ
ルボン酸（塩）溶液に含まれる溶媒を、液面から蒸発さ
せて濃縮する方法が採用されていた。Conventionally, as a method of concentrating a polycarboxylic acid (salt) solution, the polycarboxylic acid (salt) solution is stored in a large container-shaped evaporator, and the polycarboxylic acid (salt) is heated from the outer surface of the evaporator to obtain the polycarboxylic acid (salt). The method of evaporating the solvent contained in the solution from the liquid surface and concentrating it has been adopted.
【０００５】[0005]
【発明が解決しようとする課題】ところが、上記のよう
な蒸発釜を用いる濃縮方法では、ポリカルボン酸（塩）
溶液に強い泡立ちが生じ、濃縮作業に支障が出たり、濃
縮後のポリカルボン酸（塩）溶液の取り扱いや利用が行
い難いという問題があった。ポリカルボン酸（塩）溶液
は、比較的粘度が高く、蒸発釜に溜めた状態で加熱する
と溶液内部から泡立ちが生じやすいとともに、一旦発生
した泡は、濃縮後もなかなか消え難いという性質があ
る。そのため、他の液状物質の濃縮作業ではそれほど問
題にならない泡立ちが、ポリカルボン酸（塩）溶液の場
合には、きわめて重大な問題となっていた。However, in the concentration method using the above-mentioned evaporation pot, the polycarboxylic acid (salt) is used.
There was a problem that strong foaming occurred in the solution, which hindered the concentration work, and it was difficult to handle and use the concentrated polycarboxylic acid (salt) solution. The polycarboxylic acid (salt) solution has a relatively high viscosity, and when heated in a state of being stored in an evaporator, bubbles tend to be generated from the inside of the solution, and bubbles once generated are difficult to disappear even after concentration. Therefore, foaming, which is not a serious problem when concentrating other liquid substances, is a very serious problem in the case of a polycarboxylic acid (salt) solution.
【０００６】このような濃縮時の泡立ちは、上記作業性
以外の問題も誘発する。すなわち、濃縮作業により泡立
った溶液は、この溶液を分取して濃度を測定するのが難
しく、濃縮作業中に溶液の濃度確認や濃度管理を行うこ
とが出来ない。そのため、従来は、溶媒の蒸発量を測定
し、これを基にして溶液の濃度を算出し、この算出され
た濃度値を目安にしていた。しかし、溶媒の蒸発量から
算出された溶液濃度は、実際の濃度とは異なるのが普通
である。そのため、蒸発釜で一度に濃縮作業を行う各バ
ッチ毎に、濃縮作業が完了し、溶液の泡立ちが収まって
から、正確な濃度を測定し、要求濃度との違いがあれ
ば、溶媒を添加して濃度の微調整を行わなければ、目的
とする濃度の製品が得られなかった。このようなバッチ
毎の濃度の微調整作業は、きわめて煩雑であるばかり
か、濃縮作業の連続化を阻む要因ともなっていた。The foaming during concentration causes problems other than the above workability. That is, it is difficult to separate and measure the concentration of a solution that is foamed during the concentration operation, and it is not possible to confirm the concentration of the solution or control the concentration during the concentration operation. Therefore, conventionally, the evaporation amount of the solvent is measured, the concentration of the solution is calculated based on this, and the calculated concentration value is used as a guide. However, the solution concentration calculated from the evaporation amount of the solvent is usually different from the actual concentration. Therefore, for each batch in which the concentration work is carried out at once in the evaporator, the concentration work is completed, and after the foaming of the solution has stopped, the correct concentration is measured, and if there is a difference from the required concentration, the solvent is added. Unless the concentration was finely adjusted by using the above method, the desired concentration of the product could not be obtained. Such fine adjustment work of the concentration for each batch is not only extremely complicated but also a factor that hinders continuous concentration work.
【０００７】そこで、この発明の課題は、ポリカルボン
酸（塩）溶液を濃縮する方法として、泡立ちが生じ難い
方法を提供することにある。また、この発明の別の課題
は、泡立ちを生じさせることなく、ポリカルボン酸
（塩）溶液を連続的に濃縮できる方法を提供することに
ある。SUMMARY OF THE INVENTION An object of the present invention is to provide a method of condensing a polycarboxylic acid (salt) solution in which foaming hardly occurs. Another object of the present invention is to provide a method capable of continuously concentrating a polycarboxylic acid (salt) solution without causing foaming.
【０００８】[0008]
【課題を解決するための手段】上記課題を解決する、こ
の発明にかかるポリカルボン酸（塩）溶液の濃縮方法
は、分子量が３００〜１，０００，０００のポリカルボ
ン酸（塩）溶液を、加熱面に逐次供給することにより溶
媒を蒸発させて濃縮することを特徴とする。また、この
発明にかかるポリカルボン酸（塩）の連続濃縮方法は、
分子量が３００〜１，０００，０００のポリカルボン酸
（塩）溶液を、循環経路で循環させつつ、加熱面に逐次
供給して溶媒を蒸発させて濃縮する連続濃縮方法であっ
て、前記循環経路に設置された濃度検知手段により循環
中の溶液の濃度を測定し、所望の濃度に達しない溶液
は、循環を継続させて再度加熱すると共に、所望の濃度
に達した溶液は、前記循環経路から抜き出して回収する
ことを特徴とする。A method for concentrating a polycarboxylic acid (salt) solution according to the present invention, which solves the above-mentioned problems, provides a polycarboxylic acid (salt) solution having a molecular weight of 300 to 1,000,000, It is characterized in that the solvent is evaporated and concentrated by successively supplying to the heating surface. Further, the continuous concentration method of the polycarboxylic acid (salt) according to the present invention,
A continuous concentration method in which a polycarboxylic acid (salt) solution having a molecular weight of 300 to 1,000,000 is circulated in a circulation path and is sequentially supplied to a heating surface to evaporate a solvent to concentrate the solution. The concentration of the solution in the circulation is measured by the concentration detection means installed in the solution, and the solution that does not reach the desired concentration is heated again by continuing the circulation, and the solution that reaches the desired concentration is discharged from the circulation path. It is characterized by extracting and collecting.
【０００９】ポリカルボン酸（塩）溶液は、ポリカルボ
ン酸（塩）が溶媒に溶解したもので、各種用途、例え
ば、水処理剤、洗剤ビルダー、分散剤として有用なもの
である。ポリカルボン酸は、分子中にカルボキシル基を
複数個有する合成高分子であり、通常は１種以上の不飽
和カルボン酸を、必要により不飽和カルボン酸以外の単
量体を共重合成分に用いて、重合もしくは共重合するこ
とにより得られる。また、ポリカルボン酸（塩）は、上
記ポリカルボン酸を、各種塩基性物質、例えば、アンモ
ニア、苛性ソーダ、苛性カリ等で中和させたものであ
る。The polycarboxylic acid (salt) solution is obtained by dissolving the polycarboxylic acid (salt) in a solvent and is useful for various purposes such as a water treatment agent, a detergent builder and a dispersant. A polycarboxylic acid is a synthetic polymer having a plurality of carboxyl groups in the molecule, and usually one or more kinds of unsaturated carboxylic acids are used, and if necessary, a monomer other than the unsaturated carboxylic acids is used as a copolymerization component. , Polymerization or copolymerization. The polycarboxylic acid (salt) is obtained by neutralizing the above polycarboxylic acid with various basic substances such as ammonia, caustic soda and caustic potash.
【００１０】ポリカルボン酸（塩）の具体例としては、
例えば、ポリアクリル酸（塩）、ポリメタクリル酸
（塩）、ポリマレイン酸（塩）、ポリフマール酸
（塩）、ポリイタコン酸（塩）、ポリクロトン酸
（塩）、アクリル酸共重合体（塩）、メタクリル酸共重
合体（塩）、マレイン酸共重合体（塩）、フマール酸共
重合体（塩）、イタコン酸共重合体（塩）、クロトン酸
共重合体（塩）などが挙げられる。Specific examples of the polycarboxylic acid (salt) include:
For example, polyacrylic acid (salt), polymethacrylic acid (salt), polymaleic acid (salt), polyfumaric acid (salt), polyitaconic acid (salt), polycrotonic acid (salt), acrylic acid copolymer (salt), methacryl Examples thereof include acid copolymers (salts), maleic acid copolymers (salts), fumaric acid copolymers (salts), itaconic acid copolymers (salts), and crotonic acid copolymers (salts).
【００１１】ポリカルボン酸（塩）の分子量は、３００
〜１，０００，０００の範囲のものが、この発明の濃縮
方法を適用したときに良好な作用効果が達成される。ポ
リカルボン酸（塩）に含まれる溶媒としては、ポリカル
ボン酸（塩）の製造方法によっても異なるが、一般的に
は水が多く、その他の無機あるいは有機の溶媒が用いら
れる場合もある。ポリカルボン酸（塩）溶液の粘度が高
いものほど、濃縮時に泡立ちが生じ易く、かつ、泡が消
え難いが、この発明の濃縮方法では、粘度１．０〜６，
０００cps の範囲の溶液に対して、泡立ちを起こすこと
なく良好に濃縮することができる。The polycarboxylic acid (salt) has a molecular weight of 300.
Those having a range of up to 1,000,000 achieve good working effects when the concentration method of the present invention is applied. The solvent contained in the polycarboxylic acid (salt) varies depending on the method for producing the polycarboxylic acid (salt), but generally contains a large amount of water, and other inorganic or organic solvents may be used. As the viscosity of the polycarboxylic acid (salt) solution is higher, foaming is more likely to occur at the time of concentration and the bubbles are less likely to disappear, but in the concentration method of the present invention, the viscosity is 1.0 to 6,
For a solution in the range of 000 cps, good concentration can be achieved without foaming.
【００１２】ポリカルボン酸（塩）溶液を、加熱面に逐
次供給することにより溶媒を蒸発させるには、従来の各
種熱交換器などで採用されている各種の伝熱構造が採用
できる。具体的には、例えば、垂直または水平に配置さ
れた伝熱管の内部に蒸気などの加熱媒体を供給し、この
伝熱管の外面に沿ってポリカルボン酸（塩）溶液を流せ
ば、ポリカルボン酸（塩）溶液は薄層になって流れなが
ら伝熱管からの伝熱で加熱されることになる。多数の伝
熱管が配置された上方に、ポリカルボン酸（塩）溶液を
散布供給すれば、液滴状の溶液が自由落下しながら加熱
されたり、溶液が伝熱管の表面に沿って薄層状態で流れ
ながら加熱されることになる。垂直もしくは傾斜状態あ
るいは水平に配置された伝熱板にポリカルボン酸（塩）
溶液を流す方法も採用できる。何れにしても、ポリカル
ボン酸（塩）溶液が薄層状態、すなわち、伝熱面からポ
リカルボン酸（塩）溶液の蒸発表面までの厚みが薄い状
態で、加熱されるようにする。In order to evaporate the solvent by successively supplying the polycarboxylic acid (salt) solution to the heating surface, various heat transfer structures adopted in various conventional heat exchangers can be adopted. Specifically, for example, if a heating medium such as steam is supplied to the inside of a heat transfer tube arranged vertically or horizontally and a polycarboxylic acid (salt) solution is flown along the outer surface of the heat transfer tube, the polycarboxylic acid The (salt) solution is heated by heat transfer from the heat transfer tube while flowing in a thin layer. If a polycarboxylic acid (salt) solution is sprayed and supplied above a large number of heat transfer tubes, the solution in the form of droplets will be heated while free falling, or the solution will be in a thin layer along the surface of the heat transfer tubes. It will be heated while flowing. Polycarboxylic acid (salt) on the heat transfer plate arranged vertically or inclined or horizontally
A method of flowing a solution can also be adopted. In any case, the polycarboxylic acid (salt) solution is heated in a thin layer state, that is, in the state where the thickness from the heat transfer surface to the evaporation surface of the polycarboxylic acid (salt) solution is thin.
【００１３】ポリカルボン酸（塩）溶液は、加熱面が設
けられた加熱部に連続的に供給して、溶液が加熱面に対
して移動しながら加熱されるようにしたほうが、伝熱効
率が良い。ポリカルボン酸（塩）溶液を、加熱部に連続
的に供給し、濃縮された溶液を再び加熱部に送り返し
て、溶液を循環させながら濃縮すれば、高い濃度の濃縮
液を効率的に得ることができる。The polycarboxylic acid (salt) solution is continuously supplied to the heating portion provided with the heating surface so that the solution is heated while moving with respect to the heating surface, so that the heat transfer efficiency is better. .. A polycarboxylic acid (salt) solution is continuously supplied to the heating section, the concentrated solution is sent back to the heating section, and the solution is circulated for concentration to obtain a concentrated solution with a high concentration efficiently. You can
【００１４】ポリカルボン酸（塩）溶液が所望の濃度ま
で濃縮されたかどうかは、濃縮中の溶液を一部取り出し
て、その濃度を測定すれば判る。濃度を測定する方法と
しては、粘度や比重などの物理的性質を測定して、その
結果をもとに濃度を知る方法や、ｐＨ値などの化学的性
質を測定して、その結果をもとに濃度を知る方法が適用
できる。具体的な測定方法や測定器具などは、従来の通
常の各種濃縮方法や濃縮装置と同様のものが適用され
る。Whether or not the polycarboxylic acid (salt) solution has been concentrated to a desired concentration can be determined by taking out a part of the solution being concentrated and measuring the concentration. The concentration can be measured by measuring physical properties such as viscosity and specific gravity, and then knowing the concentration based on the results, or by measuring chemical properties such as pH value and then using the results. The method of knowing the concentration can be applied. As the specific measuring method and measuring instrument, those similar to the conventional ordinary various concentrating methods and concentrating devices are applied.
【００１５】ポリカルボン酸（塩）溶液を連続的に循環
させながら濃縮を行う場合、濃度の測定も溶液の循環経
路内で連続的に行い、測定された濃度の値から、溶液の
供給量や加熱温度その他の作業条件を制御したり、所定
の濃度まで濃縮された溶液を循環経路から抜き出すよう
にすれば、常に適切な条件で濃縮作業を行うことがで
き、しかも、濃縮作業を中断させることなく、濃縮液の
取り出しを連続的に行うことができる。すなわち、循環
経路に設置された濃度検知手段により循環中の溶液の濃
度を測定し、所望の濃度に達しない溶液は、循環を継続
させて再度加熱すると共に、所望の濃度に達した溶液
は、前記循環経路から抜き出して回収することで、ポリ
カルボン酸（塩）溶液の連続濃縮が可能になる。このよ
うな連続濃縮を行うための循環経路の構造は、各種化学
製品の製造装置と同様に、各種ポンプや制御弁、配管部
品などを組み合わせて構成することができる。When the polycarboxylic acid (salt) solution is continuously circulated and concentrated, the concentration is also measured continuously in the circulation route of the solution, and the amount of the solution supplied or the solution is determined from the measured concentration value. By controlling the heating temperature and other working conditions, or by extracting the solution concentrated to a predetermined concentration from the circulation path, it is possible to always perform the concentration work under appropriate conditions, and to suspend the concentration work. Instead, the concentrated liquid can be continuously taken out. That is, the concentration of the solution in the circulation is measured by the concentration detecting means installed in the circulation path, the solution which does not reach the desired concentration is heated again while continuing the circulation, and the solution which has reached the desired concentration is The polycarboxylic acid (salt) solution can be continuously concentrated by extracting it from the circulation path and collecting it. The structure of the circulation path for performing such continuous concentration can be configured by combining various pumps, control valves, piping parts, and the like, like the manufacturing apparatus for various chemical products.
【００１６】循環中の溶液の濃度を測定する方法のう
ち、比重計を用いて、測定された溶液の比重から濃度を
知る方法は、測定値と実際の濃度とがほぼ近似してお
り、回収した溶液の濃度を微調整する必要がなく、好ま
しい。比重計の具体的構造は、通常の液体配管などに組
み込まれる各種の比重計と同様のものが適用できる。溶
液の比重から濃度を知るには、予め比重と濃度の相関関
係を測定しておき、この相関関係にもとづいて、比重の
測定値を濃度に換算すればよい。Among the methods for measuring the concentration of the circulating solution, the method of knowing the concentration from the measured specific gravity of the solution using a densitometer is such that the measured value and the actual concentration are almost similar to each other. It is not necessary to finely adjust the concentration of the prepared solution, which is preferable. The specific structure of the pycnometer may be the same as that of various pycnometers incorporated in a normal liquid pipe or the like. In order to know the concentration from the specific gravity of the solution, the correlation between the specific gravity and the concentration may be measured in advance, and the measured value of the specific gravity may be converted into the concentration based on this correlation.
【００１７】[0017]
【作用】ポリカルボン酸（塩）溶液を加熱して溶媒を蒸
発除去する場合、従来の蒸発釜を用いる方法のように、
溶液の厚みが非常に分厚い状態で加熱すると、溶液の内
部で発生する気泡が溶液内に長く留まることになるの
で、気泡が大きく成長して、泡立ちを生じるものと考え
られる。これに対し、ポリカルボン酸（塩）溶液を、加
熱面に逐次供給する場合には、溶液が比較的薄い層にな
った状態で逐次加熱されることになり、伝熱効率が良い
ため、気泡が発生し難いとともに、気泡が発生しても直
ぐに溶液表面から放出されることになり、泡立ちが少な
くなるものと考えられる。When the polycarboxylic acid (salt) solution is heated to remove the solvent by evaporation, as in the conventional method using an evaporator,
If the solution is heated in a very thick state, the bubbles generated inside the solution will remain in the solution for a long time, and it is considered that the bubbles grow large and foam. On the other hand, when the polycarboxylic acid (salt) solution is sequentially supplied to the heating surface, the solution is heated sequentially in a relatively thin layer, and the heat transfer efficiency is good, so that the bubbles are not generated. It is considered that it is difficult to generate the bubbles, and even if bubbles are generated, they are immediately released from the surface of the solution, so that the bubbles are less likely to be generated.
【００１８】また、この方法では伝熱効率が良いので、
加熱エネルギーも少なくて済むようになる。Further, since heat transfer efficiency is good in this method,
It requires less heating energy.
【００１９】[0019]
【実施例】ついで、この発明の実施例を図面を参照しな
がら以下に説明する。図１は、濃縮装置の全体構造を示
している。円筒状の蒸発缶１０の内部に、低濃度部と高
濃度部の２段の熱交換器２０、３０が備えられている。
蒸発缶１０には、真空ポンプ１２が接続されてあって、
蒸発缶１０の内部を減圧できるようになっており、圧力
指示計１４および圧力調節計１５で圧力を調節すること
により、蒸発缶１０の内部圧力を一定値にコントロール
している。Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the overall structure of the concentrator. Inside the cylindrical evaporator 10, two-stage heat exchangers 20, 30 for a low concentration part and a high concentration part are provided.
A vacuum pump 12 is connected to the evaporator 10
The inside of the evaporator 10 can be depressurized, and the pressure inside the evaporator 10 is controlled to a constant value by adjusting the pressure with a pressure indicator 14 and a pressure controller 15.
【００２０】熱交換器２０、３０には、細い伝熱管が多
数水平に並べて設けられており、伝熱管の内部には加熱
媒体となる蒸気が供給される。蒸気は、蒸気供給部４０
から、それぞれエゼクタ４２、４３を経て各熱交換器２
０、３０に供給され、熱交換を終えた蒸気およびドレン
水は、コンデンサ４５で回収される。各熱交換器２０、
３０の上方には、溶液の散布器２２、３２が備えられて
おり、この散布器２２、３２から、濃縮しようとするポ
リカルボン酸（塩）溶液が、熱交換器２０、３０に向け
て散布される。各熱交換器２０、３０に散布供給された
溶液は、液滴状になって伝熱管の間を自由落下したり、
伝熱管の表面に接触して、薄層状態で伝熱管に沿って流
れ、熱交換器２０、３０の下方のそれぞれの液溜まり部
２４、３４に溜まる。液溜まり部２４、３４に溜まった
溶液は、循環ポンプ５２、５３で、それぞれの散布器２
２、３２へと戻される。すなわち、溶液は、散布器２
２、３２、熱交換器２０、３０および液溜まり部２４、
３４を結ぶ配管系を繰り返し循環しながら、濃縮される
ことになる。低濃度部の熱交換器２０につながる配管系
には、原液の供給部５６が設けられている。高濃度部の
熱交換器３０につながる配管系には、比重計６０、粘度
計６２およびｐＨ計６４の濃度検知手段となる各測定
器、ならびに、濃縮液の取り出し部５８が設けられてい
る。なお、濃度検知手段は、上記測定器６０〜６４のう
ちの、何れか１種を備えているだけでもよい。The heat exchangers 20 and 30 are provided with a large number of thin heat transfer tubes arranged side by side, and steam serving as a heating medium is supplied to the inside of the heat transfer tubes. The steam is supplied by the steam supply unit 40.
From the heat exchanger 2 through the ejectors 42 and 43, respectively.
The condenser 45 collects the steam and drain water that have been supplied to 0 and 30 and have completed heat exchange. Each heat exchanger 20,
Solution sprayers 22, 32 are provided above 30. From the sprayers 22, 32, the polycarboxylic acid (salt) solution to be concentrated is sprayed toward the heat exchangers 20, 30. To be done. The solution sprayed and supplied to each of the heat exchangers 20 and 30 becomes droplets and freely falls between the heat transfer tubes,
It contacts the surface of the heat transfer tube, flows along the heat transfer tube in a thin layer state, and collects in the respective liquid pools 24, 34 below the heat exchangers 20, 30. The solutions accumulated in the liquid reservoirs 24 and 34 are circulated by the circulation pumps 52 and 53, respectively.
Returned to 2, 32. That is, the solution is spreader 2
2, 32, the heat exchangers 20 and 30, and the liquid pool 24,
It will be concentrated while repeatedly circulating through the piping system connecting 34. A stock solution supply part 56 is provided in the piping system connected to the heat exchanger 20 in the low concentration part. The pipe system connected to the heat exchanger 30 in the high concentration part is provided with respective measuring devices which serve as concentration detecting means for the specific gravity meter 60, the viscometer 62 and the pH meter 64, and the concentrated liquid take-out portion 58. The concentration detecting means may include only one of the measuring devices 60 to 64.
【００２１】上記濃縮装置の作動について段階的に説明
する。 蒸発缶１０の内部を真空ポンプ１２で減圧し、蒸発
缶１０の内部圧力を圧力指示計１４および圧力調節計１
５で一定圧力に制御する。 蒸気供給部４０から各エゼクタ４２、４３を経て熱
交換器２０、３０に蒸気を供給する。The operation of the concentrating device will be described step by step. The inside of the evaporator 10 is decompressed by the vacuum pump 12, and the internal pressure of the evaporator 10 is adjusted to the pressure indicator 14 and the pressure controller 1.
A constant pressure is controlled at 5. Steam is supplied from the steam supply unit 40 to the heat exchangers 20 and 30 via the ejectors 42 and 43.
【００２２】 濃縮するポリカルボン酸（塩）溶液を
原液供給部５６から低濃度部の配管系に一定流量で供給
する。溶液は、散布器２２、熱交換器２０、液溜まり部
２４を循環し、熱交換器２０で蒸気からの伝熱により、
溶媒が蒸発して、徐々に濃縮されていく。 低濃度部である程度まで濃縮された溶液は、高濃度
部の配管系へと送られる。高濃度部でも溶液は、散布器
３２、熱交換器３０、液溜まり部３４を循環して、さら
に濃縮される。The polycarboxylic acid (salt) solution to be concentrated is supplied from the stock solution supply unit 56 to the piping system of the low concentration part at a constant flow rate. The solution circulates through the sprayer 22, the heat exchanger 20, and the liquid pool 24, and by heat transfer from the steam in the heat exchanger 20,
The solvent evaporates and gradually becomes concentrated. The solution concentrated to a certain extent in the low concentration part is sent to the piping system in the high concentration part. Even in the high-concentration portion, the solution circulates through the sprayer 32, the heat exchanger 30, and the liquid pool 34, and is further concentrated.
【００２３】 比重計６０、粘度計６２、ｐＨ計６４
で、循環している溶液の濃縮度をチェックし、予め設定
された特性値になった段階で、取り出し部５８からの濃
縮液の抜き出しを開始する。濃縮液の抜き出し量は、液
溜まり部３４の液面が一定に保たれる程度に設定してお
く。濃縮液の抜き出しを開始してからも、各熱交換器２
０、３０における溶液の濃縮および循環は同じように続
けられる。Specific gravity meter 60, viscometer 62, pH meter 64
Then, the degree of concentration of the circulating solution is checked, and when the preset characteristic value is reached, withdrawal of the concentrated liquid from the take-out unit 58 is started. The withdrawal amount of the concentrated liquid is set such that the liquid surface of the liquid reservoir 34 is kept constant. Even after starting the extraction of the concentrated liquid, each heat exchanger 2
Concentration and circulation of the solution at 0, 30 continues in the same way.
【００２４】 濃縮液の抜き出し中、高濃度部の溶液
濃度を、比重計６０で常に監視しておき、比重の測定値
が一定になるように、蒸気供給部４０から供給する蒸気
の圧力または量を制御する。 上記のようにして、ポリカルボン酸（塩）溶液の濃縮が
行われ、濃縮液の取り出し部５８からは、一定濃度の濃
縮液が連続的に得られる。During withdrawal of the concentrated liquid, the solution concentration in the high-concentration portion is constantly monitored by the pycnometer 60, and the pressure or amount of the steam supplied from the steam supply unit 40 is adjusted so that the measured specific gravity becomes constant. To control. As described above, the polycarboxylic acid (salt) solution is concentrated, and a concentrated solution having a constant concentration is continuously obtained from the concentrated solution outlet 58.
【００２５】つぎに、上記濃縮装置を用いて、ポリカル
ボン酸（塩）溶液の濃縮を行った具体例について説明す
る。 −実施例１− ポリカルボン酸（塩）溶液：アクリル酸／３−アリロキ
シ・２−ヒドロキシプロパンスルホン酸共重合体ナトリ
ウム塩水溶液（固型分濃度２５％、平均分子量５，００
０） 原液供給量：２８００kg/Hr 蒸気量および圧力：８５０kg/Hr ，４．４kg/cm2 濃縮液抜き出し量：１４００kg/Hr 濃縮倍率：２．０倍 上記操作条件で濃縮を行ったところ、固型分濃度が５
０．０±０．２％、粘度６００cps （２５℃）の濃縮液
が連続的に得られた。濃縮中の泡立ちは全く認められ
ず、安定かつ連続的な運転が可能であった。Next, a concrete example in which the polycarboxylic acid (salt) solution is concentrated using the above-mentioned concentrating device will be described. -Example 1-Polycarboxylic acid (salt) solution: Acrylic acid / 3-allyloxy-2-hydroxypropanesulfonic acid copolymer sodium salt aqueous solution (solid content concentration 25%, average molecular weight 5,000
0) Undiluted solution supply rate: 2800 kg / Hr Vapor amount and pressure: 850 kg / Hr, 4.4 kg / cm 2 Concentrated solution withdrawal rate: 1400 kg / Hr Concentration factor: 2.0 times Concentration of mold component is 5
A concentrated solution having a viscosity of 0.0 ± 0.2% and a viscosity of 600 cps (25 ° C.) was continuously obtained. No foaming was observed during the concentration, and stable and continuous operation was possible.
【００２６】−実施例２− ポリカルボン酸（塩）溶液：ポリアクリル酸水溶液（固
型分濃度８％、平均分子量７３０，０００） 実施例１と同じ操作条件で濃縮を行ったところ、固型分
濃度が１６．０±０．１％、粘度５，８００cps （２５
℃）の濃縮液が連続的に得られた。濃縮中の泡立ちは全
く認められず、安定かつ連続的な運転が可能であった。-Example 2-Polycarboxylic acid (salt) solution: polyacrylic acid aqueous solution (solid content 8%, average molecular weight 730,000) Concentration was carried out under the same operating conditions as in Example 1 to obtain a solid. Minute concentration 16.0 ± 0.1%, viscosity 5,800cps (25
(° C) was continuously obtained. No foaming was observed during the concentration, and stable and continuous operation was possible.
【００２７】−実施例３− ポリカルボン酸（塩）溶液：ポリアクリル酸ナトリウム
水溶液（固型分濃度１０％、平均分子量３００） 実施例１と同じ操作条件で濃縮を行ったところ、固型分
濃度が２０．０±０．１％、粘度２．２cps （２５℃）
の濃縮液が連続的に得られた。濃縮中の泡立ちは全く認
められず、安定かつ連続的な運転が可能であった。Example 3-Polycarboxylic acid (salt) solution: sodium polyacrylate aqueous solution (concentration of solid content 10%, average molecular weight 300) Concentration was carried out under the same operating conditions as in Example 1 to obtain solid content. Concentration 20.0 ± 0.1%, viscosity 2.2cps (25 ℃)
A concentrated solution of was obtained continuously. No foaming was observed during the concentration, and stable and continuous operation was possible.
【００２８】[0028]
【発明の効果】以上に述べた、この発明にかかるポリカ
ルボン酸（塩）溶液の濃縮方法によれば、従来の方法で
は泡立ちによる種々の弊害が生じていたポリカルボン酸
（塩）溶液を濃縮しても、泡立ちが発生し難くなる。そ
の結果、濃縮後の取り扱いが行い易い品質良好な濃縮液
が得られる。As described above, according to the method for concentrating a polycarboxylic acid (salt) solution according to the present invention, the polycarboxylic acid (salt) solution, which has been disadvantageous due to foaming in the conventional method, is concentrated. However, foaming is less likely to occur. As a result, it is possible to obtain a concentrated liquid of good quality that is easy to handle after concentration.
【００２９】しかも、ポリカルボン酸（塩）溶液を加熱
する際の伝熱効率も非常に良くなるので、濃縮作業に必
要な熱エネルギーが削減でき、濃縮作業のコスト低減に
も大きく貢献できることになる。さらに、この発明にか
かるポリカルボン酸（塩）溶液の連続濃縮方法によれ
ば、従来のバッチ作業に比べて、はるかに能率的に濃縮
作業が行え、また、回収した濃縮液に対して、溶媒添加
による濃度の微調整を行うような面倒な作業が不要にな
る。その結果、所望濃度の濃縮液を、連続的に効率良く
生産することができるようになり、生産性が格段に向上
する。Moreover, since the heat transfer efficiency at the time of heating the polycarboxylic acid (salt) solution is also extremely improved, the heat energy required for the concentration work can be reduced and the cost of the concentration work can be greatly reduced. Further, according to the method for continuously concentrating a polycarboxylic acid (salt) solution according to the present invention, the concentration work can be performed much more efficiently than the conventional batch work, and the collected concentrate can be treated with a solvent. There is no need for troublesome work such as fine adjustment of concentration by addition. As a result, a concentrated solution having a desired concentration can be continuously and efficiently produced, and the productivity is remarkably improved.
【図１】 この発明の実施例を示す濃縮装置の全体構造
図FIG. 1 is an overall structural diagram of a concentrating device showing an embodiment of the present invention.
１０ 蒸発缶 ２０、３０ 熱交換器 ２２、３２ 散布器 ６０ 比重計 10 Evaporator 20, 30 Heat exchanger 22, 32 Disperser 60 Density meter
───────────────────────────────────────────────────── フロントページの続き (72)発明者 三宅 春治 兵庫県姫路市網干区興浜字西沖992番地の １ 株式会社日本触媒内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Haruji Miyake 1 992, Nishioki, Okihama, Aboshi-ku, Himeji-shi, Hyogo Prefecture Nippon Shokubai Co., Ltd.
Claims (5)
ポリカルボン酸（塩）溶液を、加熱面に逐次供給するこ
とにより溶媒を蒸発させて濃縮することを特徴とするポ
リカルボン酸（塩）溶液の濃縮方法。1. A polycarboxylic acid (salt) characterized in that a solution of a polycarboxylic acid (salt) having a molecular weight of 300 to 1,000,000 is successively supplied to a heating surface to evaporate and concentrate the solvent. How to concentrate the solution.
酸（塩）溶液の２５℃における粘度が、１．０〜６，０
００cps の範囲であるポリカルボン酸（塩）溶液の濃縮
方法。2. The method according to claim 1, wherein the viscosity of the polycarboxylic acid (salt) solution at 25 ° C. is 1.0 to 6,0.
A method for concentrating a polycarboxylic acid (salt) solution in the range of 00 cps.
カルボン酸（塩）溶液を散布して加熱面に逐次供給する
ポリカルボン酸（塩）溶液の濃縮方法。3. The method for concentrating a polycarboxylic acid (salt) solution according to claim 1 or 2, wherein the polycarboxylic acid (salt) solution is sprayed and sequentially supplied to the heating surface.
ポリカルボン酸（塩）溶液を、循環経路で循環させつ
つ、加熱面に逐次供給して溶媒を蒸発させて濃縮する連
続濃縮方法であって、前記循環経路に設置された濃度検
知手段により循環中の溶液の濃度を測定し、所望の濃度
に達しない溶液は、循環を継続させて再度加熱すると共
に、所望の濃度に達した溶液は、前記循環経路から抜き
出して回収することを特徴とするポリカルボン酸（塩）
溶液の連続濃縮方法。4. A continuous concentration method in which a solution of a polycarboxylic acid (salt) having a molecular weight of 300 to 1,000,000 is circulated in a circulation path and sequentially supplied to a heating surface to evaporate and concentrate the solvent. Then, the concentration of the solution in the circulation is measured by the concentration detecting means installed in the circulation path, and if the solution does not reach the desired concentration, the circulation is continued and heated again, and the solution reaching the desired concentration is And a polycarboxylic acid (salt) characterized by being extracted from the circulation route and recovered.
Method of continuous concentration of solution.
として比重計を用いるポリカルボン酸（塩）溶液の連続
濃縮方法。5. The method for continuously concentrating a polycarboxylic acid (salt) solution according to claim 4, wherein a hydrometer is used as a concentration detecting means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04727492A JP3219295B2 (en) | 1992-03-04 | 1992-03-04 | Concentration method and continuous concentration method for polycarboxylic acid (salt) solution |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04727492A JP3219295B2 (en) | 1992-03-04 | 1992-03-04 | Concentration method and continuous concentration method for polycarboxylic acid (salt) solution |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05247114A true JPH05247114A (en) | 1993-09-24 |
| JP3219295B2 JP3219295B2 (en) | 2001-10-15 |
Family
ID=12770717
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP04727492A Expired - Fee Related JP3219295B2 (en) | 1992-03-04 | 1992-03-04 | Concentration method and continuous concentration method for polycarboxylic acid (salt) solution |
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| Country | Link |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1324057C (en) * | 2002-03-20 | 2007-07-04 | 株式会社日本触媒 | Method for preparing polyacrylicacid |
-
1992
- 1992-03-04 JP JP04727492A patent/JP3219295B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1324057C (en) * | 2002-03-20 | 2007-07-04 | 株式会社日本触媒 | Method for preparing polyacrylicacid |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3219295B2 (en) | 2001-10-15 |
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