JPS6126502A - Continuous production of bleaching liquid - Google Patents

Abstract

PURPOSE:To produce bleaching liquid continuously and stably, in high efficiency, by dividing the reaction zones in the production process into two stages, introducing chlorine gas dividedly to each stage, and reacting milk of lime with chlorine gas in the zones under the optimum absorption and reaction conditions. CONSTITUTION:A bleaching liquid composed of calcium hypochlorite as a main component is produced from milk of lime and chlorine gas. In the above process, the reaction zone is divided into two stages, and chlorine gas is introduced dividedly into each stage. The effective chlorine concentrations in the reaction solution in the first reaction tank 1 and the second reaction tank 2 constituting the first-stage reaction zone are controlled constantly to 40-100g/l by adjusting the feed of the lime milk and chlorine gas, and the effective chlorine concentration in the third reaction tank 3 constituting the second-stage reaction zone is maintained at a specific level to effect the completion of the reaction and obtain the objective bleaching liquid. The concentration is preferably detected with ORPE3, and the flow of a small amount of the chlorine gas is controlled with the automatic valve V4.

Description

【発明の詳細な説明】 本発明は、次亜塩素酸ソーダ溶液と並んで、厭、パルプ
、繊維類、天然物等の漂白、上下水道やプールの殺菌、
無機及び有機の工業薬品類の原料等、広範囲な工業的用
途を有する次亜塩素酸カルシウムを主成分とするさらし
液を連続的に効率良く製造する方法に関する。DETAILED DESCRIPTION OF THE INVENTION In addition to the sodium hypochlorite solution, the present invention can be used to bleach pulp, fibers, natural products, etc., sterilize water supplies, sewage systems, and swimming pools.
This invention relates to a method for continuously and efficiently producing a bleaching solution containing calcium hypochlorite as a main component, which has a wide range of industrial uses such as raw materials for inorganic and organic industrial chemicals.

従来、石灰乳液に塩素を作用させて、次亜塩素酸カルシ
ウムを主成分とするさらし液の工業的製造方法としては
、次亜塩素酸ソーダ溶液の製造に類似して、例えば、次
の方法が知られている。Conventionally, as an industrial method for producing a bleaching solution containing calcium hypochlorite as a main component by applying chlorine to a lime emulsion, the following method, for example, is similar to the production of a sodium hypochlorite solution. Are known.

（１）吸収塔と液循環槽を設け、該吸収塔の塔頂より石
灰乳液を流下し、該吸収塔の塔底から塩素ガスを送入し
、該塔底液は該循環槽に受けてポンプにより再び該塔頂
に送シ、逐次有効塩素濃度を上げて反応を完結させる方
法。(1) An absorption tower and a liquid circulation tank are provided, lime emulsion flows down from the top of the absorption tower, chlorine gas is introduced from the bottom of the absorption tower, and the bottom liquid is received in the circulation tank. A method in which chlorine is sent to the top of the column again using a pump, and the effective chlorine concentration is gradually increased to complete the reaction.

（２）攪拌機を備えた石灰乳液槽の底部よシ、ナツシュ
ポンプなどで塩素ガスを吹き込み、次オに該反応溶液中
の有効塩素濃度を上げて反応を完結させる方法。(2) A method in which chlorine gas is blown into the bottom of a lime emulsion tank equipped with a stirrer using a nutsch pump, etc., and then the effective chlorine concentration in the reaction solution is increased to complete the reaction.

（３）循環石灰乳液配管途中に設けたエジェクターに塩
素ガスを吹き込み該石灰乳液に塩素を吸収反応させる方
法。(3) A method in which chlorine gas is blown into an ejector installed in the circulating lime latex piping to cause the lime latex to absorb and react with chlorine.

などのパツヂ方式が広く採用されている。Patsuji methods such as these are widely adopted.

方式で製造される。所望の有効塩素濃度に到達したら、
一旦、塩素ガスを止め、生成さらし液を抜塩素酸カルシ
ウム製造反応の進行と共に次第に有効塩素濃度を上げて
いくという煩雑な操業が繰シ返えされる。manufactured by the method. Once the desired available chlorine concentration is reached,
The complicated operation of once stopping the chlorine gas, removing the produced bleaching solution, and gradually increasing the effective chlorine concentration as the calcium chlorate production reaction progresses is repeated.

さらし液の製造反応は次式で示される如く、２　Ｃａ　
（ＯＨ）＊　＋　２　Ｃ／、　＋　ａｑ＝　Ｃａ（ＯＣ
ｔ）、　＋ＣａＣ４＋２Ｈ１０＋５０．９９ＫＣａｔ可
成シの発熱反応であり、液面上昇による副反応を抑える
ため実際の製造にあたっては、溶液の冷却装置を設け、
３５℃以下に保って反応が行われるし、又、石灰乳液中
の水酸化カルシウムの水に対する溶解度は２０℃で１．
６　ｔ／ｌと極めて小さく、しかも温度と共に溶解度は
減少する。The manufacturing reaction of the bleaching solution is as shown by the following formula, 2 Ca
(OH)* + 2 C/, + aq= Ca(OC
t), +CaC4+2H10+50.99KCat It is an exothermic reaction that can be formed, and in order to suppress side reactions due to rising liquid level, a solution cooling device is installed during actual production.
The reaction is carried out by keeping the temperature below 35°C, and the solubility of calcium hydroxide in lime emulsion in water is 1.5°C at 20°C.
The solubility is extremely small at 6 t/l, and the solubility decreases with temperature.

従って大部分の水酸化カルシウムは懸濁スラリー状態で
あり、易溶性の例えば苛性ソーダ溶液に塩素ガスを吹き
込み次亜塩素酸ソーダ溶液の製造と比べて不均一系であ
シ、且つ反応速度は可成シ遅く、水酸化カルシウムの溶
解速度、溶液の組成などによって左右されるという難点
も有する。Therefore, most of the calcium hydroxide is in a suspended slurry state, and compared to producing a sodium hypochlorite solution by blowing chlorine gas into an easily soluble caustic soda solution, for example, it is a heterogeneous system, and the reaction rate is fair. It also has the disadvantage that it is slow and depends on the dissolution rate of calcium hydroxide, the composition of the solution, etc.

本発明者らは、近年、苛性ソーダは多量のエネルギーを
要する電解法によって製造される高価なものであること
から、これを原料とする次亜塩素酸ソーダ溶液に代って
、安価な石灰乳液を原料とする次亜塩素酸カルシウムを
主成分とするさらし液の製造が見直されてきた現状に鑑
み、工業的規模で安定且つ効率よく連続的に製造する方
法を見出すべく鋭意研究を重ねてきた。In recent years, the present inventors have developed an inexpensive lime emulsion to replace the sodium hypochlorite solution that uses caustic soda as a raw material, since caustic soda is an expensive product produced by an electrolytic method that requires a large amount of energy. In view of the current situation where the production of a bleaching solution whose main component is calcium hypochlorite as a raw material is being reconsidered, we have been conducting extensive research to find a method for producing it stably, efficiently and continuously on an industrial scale.

即ち、本発明者らは、工業的に実施し得る連続製造法を
開発すべく種々の前記せる問題点について検討を行った
結果、次の様な種々の知見を得た。That is, the present inventors investigated various problems mentioned above in order to develop an industrially applicable continuous production method, and as a result, the following various findings were obtained.

石灰乳液中の水酸化カルシウムの溶解度は、次亜塩素酸
カルシウム生成による有効塩素濃度増加と共に微妙に変
化する、消石灰品質や反応条件により若干異るが傾向は
音間−で、具体的には石灰乳液に塩素ガスを吹き込むと
、有効塩素濃度的１０２μで溶存水酸化カルシウムは最
低となり、塩素化が進み有効塩素濃度が増加するにつれ
、直線的に増加し、有効塩素濃度３５〜４０　ｆ／ｌで
最初の石灰乳液の水酸化カルシウム溶解度を越えて増加
していく。有効塩素濃度６０〜９０　ｔ／ｌに至れば、
石灰乳液の溶解度より３０〜４０％増加する。然し、更
に有効塩素濃度が増加すると、逆に、急激に溶解度が減
少してくる。The solubility of calcium hydroxide in lime emulsion changes slightly as the effective chlorine concentration increases due to the formation of calcium hypochlorite.Although it varies slightly depending on the quality of slaked lime and reaction conditions, the tendency is similar. When chlorine gas is blown into the emulsion, dissolved calcium hydroxide reaches its lowest level at an effective chlorine concentration of 102μ, increases linearly as chlorination progresses and the effective chlorine concentration increases, and reaches an effective chlorine concentration of 35 to 40 f/l. Calcium hydroxide solubility increases beyond the initial lime emulsion. If the effective chlorine concentration reaches 60-90 t/l,
The solubility is increased by 30-40% over that of lime emulsion. However, as the available chlorine concentration further increases, the solubility decreases rapidly.

この様な現象は理由は明らかでないが有効塩素濃度の変
動に伴い、Ｃａ　（ＯＣｔ）ｔの外にＣａ　（ＯＣｔ）
ｔ　’２Ｃａ　（ＯＨ入やＣａＣ４・ＸＣａ　（ＯＨ入
のような複塩生成による複雑な変化があるものと推考さ
れる。The reason for this phenomenon is not clear, but as the available chlorine concentration fluctuates, Ca (OCt) is added to Ca (OCt)t.
It is presumed that there are complex changes due to the formation of double salts such as t'2Ca (OH) and CaC4.XCa (OH).

従って、石灰乳液に塩素ガスを吹き込むときは反応開始
直後および反応後半は効率よい吸収反応が期待できず、
未反応塩素ガスの放出が多くなるということが明らかと
なった。Therefore, when blowing chlorine gas into lime emulsion, an efficient absorption reaction cannot be expected immediately after the start of the reaction and in the latter half of the reaction.
It has become clear that a large amount of unreacted chlorine gas is released.

即ち、例えば、易溶性の苛性ソーダ溶液に塩素ガスを吹
き込んで次亜塩素酸ソーダ溶液を製造する場合には未反
応塩素ガスの放出なく該反応が進行する条件であっても
、石灰乳液に塩素ガスを吹き込む場合は、該石灰乳液の
溶解度の高まった状態では未反応塩素ガスの放出が数ｐ
ｐｍであるが該石灰乳液の溶解度の低い反応開始直後お
よび反応後半では該未反応塩素ガスの放出が数千ｐｐｍ
至乃数チに達する。That is, for example, when producing a sodium hypochlorite solution by blowing chlorine gas into an easily soluble caustic soda solution, even if the reaction proceeds without releasing unreacted chlorine gas, chlorine gas is added to the lime emulsion. When injecting chlorine into the lime emulsion, unreacted chlorine gas is released by a few pp when the lime emulsion has high solubility.
pm, but immediately after the start of the reaction and in the latter half of the reaction when the lime emulsion has low solubility, the unreacted chlorine gas is released at several thousand ppm.
It reaches several degrees.

従って上記未反応塩素ガスの放出を抑え、さらし液を製
造することは反応開始時には塩素ガス導入量を低くせざ
るを得す、これは極めて低生産性であり工業的に望まし
くない。Therefore, in order to suppress the release of unreacted chlorine gas and produce a bleaching solution, it is necessary to reduce the amount of chlorine gas introduced at the start of the reaction, which leads to extremely low productivity and is industrially undesirable.

又、反応開始時の一時的に多量の未反応塩素ガスの発生
を許容し、その代りに排気の後処理工程に塩素ガス吸収
用除害設備を設けることも大きな設備投資あるいは複雑
な操業管理等から工業的に得気でない。Additionally, allowing a large amount of unreacted chlorine gas to be generated temporarily at the start of the reaction, and instead installing chlorine gas absorption equipment in the exhaust gas post-treatment process, requires large capital investment or complicated operational management. It's not good for the industry.

本発明者らは、以上の如き知見から石灰乳液に塩素ガス
を反応させ、次亜塩素酸カルシウムを主成分とするさら
し液を連続的に効率よく且つ安定に製造する方法として
、最適な吸収反応帯域を形成させ該石灰乳液と該塩素ガ
スとを反応させることが最も適切な解決策であることを
見出し、本発明に至ったものである。Based on the above knowledge, the present inventors have developed an optimal absorption reaction as a method for continuously, efficiently and stably producing a bleaching solution containing calcium hypochlorite as the main component by reacting lime emulsion with chlorine gas. We have found that the most appropriate solution is to form a zone and react the lime emulsion with the chlorine gas, leading to the present invention.

即ち、本発明は、 石灰乳液と塩素ガスよシ、次亜塩素酸カルシウムを主成
分とするさらし液の製造李逢方法に於いて、該製造に於
ける反応帯域を２段に分け各段に塩素ガスを分割して導
入し、且つ、該矛１段反応帯域においての該反応溶液中
の有効塩素濃度は４０〜１００　ｆｌｔを常に保持する
よう導入石灰乳液及び塩素ガスを調節し、・該第２段反
応帯域では所望の有効塩素濃度に該塩素化反応を完結せ
しめることを特徴とするさらし液の連続製造法 を提供せんとするものである。That is, the present invention provides a method for producing a bleaching solution mainly composed of lime emulsion, chlorine gas, and calcium hypochlorite, in which the reaction zone in the production is divided into two stages and each stage is divided into two stages. Introduce chlorine gas in portions, and adjust the introduced lime emulsion and chlorine gas so that the effective chlorine concentration in the reaction solution in the first stage reaction zone is always maintained at 40 to 100 flt. It is an object of the present invention to provide a continuous method for producing a bleaching solution, which is characterized in that the chlorination reaction is completed to a desired effective chlorine concentration in the two-stage reaction zone.

本発明で使用する石灰乳液は、消石灰に水を加えて混合
して得られた、懸濁状のスラリーである。The lime emulsion used in the present invention is a suspended slurry obtained by adding water to slaked lime and mixing it.

消石灰は市販されているものあるいはカルシウムカーバ
イドに水を反応させてアセチレンガスを発生させた後の
残渣で水酸化カルシウムを主成分とするカーバイド滓で
もよい。The slaked lime may be a commercially available one or a carbide slag containing calcium hydroxide as a main component, which is a residue after reacting calcium carbide with water to generate acetylene gas.

これらは微粉末のものが好適である。These are preferably fine powders.

この消石灰は例えば、攪拌機付きの混合槽で水と混合さ
れ一般に１０〜１５重量％の濃度の石灰乳液として使用
される。This slaked lime is mixed with water, for example, in a mixing tank equipped with a stirrer, and is used as a lime emulsion, generally at a concentration of 10 to 15% by weight.

又、本発明で使用する塩素ガスは、略１００ヂの液体塩
素、電解槽より排出される種々の濃度の塩素ガス、液体
塩素製造時に排出される低濃度の塩素ガス（約１０〜７
０容量チ）などが使用でき、低濃度の塩素ガスの場合は
１００係塩素換算で使用できる。In addition, the chlorine gas used in the present invention includes liquid chlorine of approximately 100°C, chlorine gas of various concentrations discharged from an electrolytic tank, and low-concentration chlorine gas (approximately 10 to 70°C) discharged during liquid chlorine production.
(0 capacity) can be used, and in the case of low concentration chlorine gas, it can be used in terms of 100% chlorine.

本発明で反応帯域とは、導入された石灰乳液が塩素ガス
と反応し、所望の有効塩素濃度に至るまでの反応域であ
って、該反応帯域は２段に分けられており、各段に塩素
ガスが分割導入される。In the present invention, the reaction zone is a reaction zone where introduced lime emulsion reacts with chlorine gas to reach a desired effective chlorine concentration, and the reaction zone is divided into two stages. Chlorine gas is introduced in portions.

矛１段反応帯域は、石灰乳液が供給され、導入塩素ガス
と反応する帯域であって、該反応帯域の反応溶液中の有
効塩素濃度は常に４０〜１００　ｔ／１１好ましくは、
４０〜９０ｔμ、特に好ましくは５０〜７０　ｆｌｔを
保持するよう該石灰乳液の供給量及び該塩素ガスの流量
が調節される。The first-stage reaction zone is a zone where lime emulsion is supplied and reacts with the introduced chlorine gas, and the effective chlorine concentration in the reaction solution in the reaction zone is always 40 to 100 t/11, preferably,
The supply amount of the lime emulsion and the flow rate of the chlorine gas are adjusted to maintain 40 to 90 tμ, particularly preferably 50 to 70 flt.

この有効塩素濃度が４０　ｆ／を未満と過少の場合ある
いは１００２μを超えて過大の場合には、塩素ガスの上
記石灰乳液への吸収反応が悪く、未反応塩素ガスの放出
が大となシ工業的に安定した効率的な製造は期待できな
い。If the effective chlorine concentration is too low (less than 40 f/) or too high (more than 1002μ), the absorption reaction of chlorine gas into the lime emulsion will be poor, and the release of unreacted chlorine gas will be a major problem in industry. Therefore, stable and efficient production cannot be expected.

第２段反応帯域は前記矛１段反応帯域より送入される反
応溶液の有効塩素濃度を所望の値に調整し完結する帯域
であって、該帯域では過塩素化反応などの副反応防止か
ら低い塩素ガス量で調節される。The second stage reaction zone is a zone where the effective chlorine concentration of the reaction solution fed from the first stage reaction zone is adjusted to a desired value, and this zone is used to prevent side reactions such as perchlorination reactions. Adjusted by low chlorine gas amount.

上記矛１、第２反応帯域は、夫々１個の反応槽又は吸収
塔（吸収塔以下、省略することあり）であってもよいが
、複数個の反応槽を直列に配置してもよい。The first reaction zone and the second reaction zone may each be a single reaction tank or an absorption tower (absorption tower and the following may be omitted), but a plurality of reaction tanks may be arranged in series.

例えば、矛１図に示す如く上記矛１段反応帯域をに第１
反応槽と２ニオ２反応槽に上記第２段反応帯域ｔ−ａ　
：＞ｇ反応槽とすることもできる。For example, as shown in Figure 1, the first stage reaction zone is
The above second stage reaction zone t-a is placed in the reaction tank and the 2-nitrogen 2 reaction tank.
:>g reaction tank can also be used.

本発明で有効塩素濃度の検知は、工業的にはｐＨ測定あ
るいは酸化還元電位（以下、ＯＲＰと省略することがあ
る）の測定値から間接的に検知することが望ましい。In the present invention, the effective chlorine concentration is preferably detected industrially indirectly from a pH measurement or a measured value of oxidation-reduction potential (hereinafter sometimes abbreviated as ORP).

次に、本発明の製造法を、矛１図を以って更に詳細に説
明する。Next, the manufacturing method of the present invention will be explained in more detail with reference to Figure 1.

′ｙＰ１図は本発明方法の実施に適当な装置の１例であ
る。４は石灰乳液貯槽、１．２４’を才１段反応帯域に
相当する第１反応槽、第２反応槽、３は第２段反応帯域
に相当する第３反応槽Ｃｓ　、Ｃｍ　、Ｃｓは冷却用熱
交換器、５はさらし液貯槽を示す。Figure 'yP1 is an example of an apparatus suitable for carrying out the method of the invention. 4 is a lime emulsion storage tank, 1.24' is the first reaction tank corresponding to the first stage reaction zone, the second reaction tank, 3 is the third reaction tank corresponding to the second stage reaction zone Cs, Cm, Cs are cooling 5 indicates a bleaching liquid storage tank.

石灰乳液は攪拌機Ｓ４によって攪拌混合されておル、ポ
ンプＰ４によって循環されている。また該石灰乳液はパ
ルプ２２によって一定流量に調節され第１反応槽１に導
入される。The lime emulsion is stirred and mixed by a stirrer S4 and circulated by a pump P4. Further, the lime emulsion is adjusted to a constant flow rate by the pulp 22 and introduced into the first reaction tank 1.

’　　　；！ｔ’１反応槽１は攪拌機Ｓ１によって攪拌
されておシ、ポンプＰ、によって冷却用熱交換器Ｃ３を
経て循環されておシ、塩素ガスはパルプ２０によって一
定流量で導入される。第１反応槽１の反応溶液はレベル
計り、によって一定になるよう自動弁ｖ１によって調節
され導管１２より第２反応槽２に導入される。';! The t'1 reaction tank 1 is stirred by a stirrer S1 and circulated by a pump P through a cooling heat exchanger C3, and chlorine gas is introduced at a constant flow rate by a pulp 20. The reaction solution in the first reaction tank 1 is level-metered and regulated by an automatic valve v1 to maintain a constant level, and then introduced into the second reaction tank 2 through a conduit 12.

第２反応槽２も攪拌機Ｓ、によって攪拌されておシ、ポ
ンプＰ！によって冷却用熱交換器Ｃ３を経て循環されて
おり、塩素ガスはパルプ２１によって一定流量で導入さ
れる。２２反応槽２の反応溶液はレベル計Ｌｍによって
一定シ・こなる１う自動弁Ｖ、　Ｋよって調節され導管
１３より矛３反応槽３に導入される。The second reaction tank 2 is also stirred by the stirrer S, and the pump P! The chlorine gas is circulated through the cooling heat exchanger C3 by the pulp 21, and the chlorine gas is introduced at a constant flow rate by the pulp 21. The reaction solution in the reaction tank 2 is regulated at a constant level by a level meter Lm, and is regulated by automatic valves V and K, and introduced into the reaction tank 3 through a conduit 13.

第３反応槽３は攪拌機Ｓ４によって攪拌されており、ポ
ンプＰ、によって冷却用熱交換器Ｃｓを経て循環されて
おり、塩素ガスは所望の有効塩素濃度になるようＯＲＰ
　Ｅ３で検知し、自動弁ｖ４によって調節され導入され
る、第３反応槽３の反応溶液はレベル計り、によって一
定になるよう自動弁Ｖ、によつ′Ｃ調節され導管１４よ
りさらし液貯槽５に送液される。The third reaction tank 3 is stirred by an agitator S4, and is circulated by a pump P through a cooling heat exchanger Cs, and the chlorine gas is ORPed to a desired effective chlorine concentration.
The reaction solution in the third reaction tank 3, which is detected by E3 and regulated and introduced by automatic valve V4, is level-metered, and is regulated by automatic valve V to be constant by 'C, and then transferred from conduit 14 to exposure liquid storage tank 5. The liquid is sent to

本発明の特徴は、塩素化反応を２段で行い、該塩素化反
応の第１段反応帯域である第１反応槽１、第２反応槽２
、の反応溶液中の有効塩素濃度は、何れも４０〜１００
　ｙ／ｌの範囲内に常に保持されなければならない。The feature of the present invention is that the chlorination reaction is carried out in two stages, a first reaction tank 1 and a second reaction tank 2, which are the first stage reaction zone of the chlorination reaction.
, the effective chlorine concentration in the reaction solution is 40 to 100.
It must always be kept within the range y/l.

これはＯＲＰ　Ｅｓ、０ＲＰＥ、ｖｃヨッテ常時監視さ
れる。This is constantly monitored by ORP Es, 0RPE, and vc yachts.

上記の夫々の反応槽に導入する塩素ガス量は、矛１反応
槽１に供給される石灰乳液量によって決定されるが、該
塩素ガスおよび該石灰乳液の夫々に水酸化カルシウムの
溶解度の急激な上昇をもたらす矛１反応槽１に重点的に
塩素ガスの流量の多い流量比率とすることもでき工業的
には好ましい。The amount of chlorine gas introduced into each of the above reaction tanks is determined by the amount of lime emulsion supplied to reaction tank 1, but the rapid solubility of calcium hydroxide in each of the chlorine gas and the lime emulsion is determined by the amount of lime emulsion supplied to reaction tank 1. It is also possible to set the flow rate ratio such that the flow rate of chlorine gas is concentrated in the reaction tank 1 that causes the increase, which is industrially preferable.

又塩素ガスおよび石灰乳液の夫々の流量あるいは流量比
率は常時一定であることは要せず、上記矛１反応槽１お
よび第２反応槽２の夫々の反応溶液中の有効塩素濃度が
４０〜１００ｔμを保持できれば種々の条件変動に伴い
変動させてもよい。Further, the respective flow rates or flow rate ratios of chlorine gas and lime emulsion do not need to be constant at all times, and the effective chlorine concentration in each of the reaction solutions in the first reaction tank 1 and the second reaction tank 2 is 40 to 100 tμ. As long as it can be maintained, it may be changed in response to various condition changes.

前記塩素化反応の第２段反応帯域である矛３反応槽３は
、前記１１１段反応帯域で殆んど塩素化された反応溶液
を僅少な塩素ガスで微調整し所望の有効塩素濃度を有す
るさらし液となすが、工業的にはＯＲＰ　Ｅａで検知し
、僅少の塩素ガ、スを自動弁ｖ４によって調節すること
が好ましい。The third reaction tank 3, which is the second stage reaction zone of the chlorination reaction, has a desired effective chlorine concentration by finely adjusting the reaction solution, which was almost chlorinated in the 111th stage reaction zone, with a small amount of chlorine gas. Although it is used as a bleaching solution, industrially it is preferable to detect it with ORP Ea and adjust the slight amount of chlorine gas with automatic valve v4.

以下、実施例及び比較例によシ本発明方法の実施態様を
更に具体的に説明する。但し、本発明は、斯る実施例に
よル、何等限定されるもので＃′ｉない。Hereinafter, embodiments of the method of the present invention will be explained in more detail using Examples and Comparative Examples. However, the present invention is not limited in any way to these Examples.

実施例 矛１図に示す製造装置を使用し、第１反応槽１、第２反
応槽２、ツ・３反応槽３に予め調整した有効塩素濃度５
８．２　ｔ／ｌ、　８８．４　ｆ／ｌ、　９８．１　ｆ
／ｌの反応溶液を夫々８００Ｌ仕込んだ。Example 1 Using the production equipment shown in Figure 1, the effective chlorine concentration 5 was adjusted in advance in the first reaction tank 1, second reaction tank 2, and three reaction tanks 3.
8.2 t/l, 88.4 f/l, 98.1 f
800 L/l of reaction solution was charged in each case.

石灰乳液貯槽４には濃度１１．８重量％の石灰乳液を準
備した。A lime emulsion having a concentration of 11.8% by weight was prepared in the lime emulsion storage tank 4.

該貯槽Ａの石灰乳液をポンプＰ４で５５６．２４／Ｈの
供給量で３・１反応槽１に導入し、矛ｌ、第２゜第３反
応槽の液面は８００ｔを保持するようレベル計Ｌ＋　、
Ｌｔ　、Ｌｓを設定した。The lime emulsion in storage tank A was introduced into 3.1 reaction tank 1 at a supply rate of 556.24/hour using pump P4, and level meters were used to maintain the liquid level in the second and third reaction tanks at 800 tons. L+,
Lt and Ls were set.

一方、ＯＲＰ　Ｅｘは７３５　ｍＶ（有効塩素濃度９８
．０μ相当）に設定し、塩素ガス（純度９６．７　％　
）を矛１反応槽１に１１．０　Ｖ肩、第２反応槽２に５
．５Ｎｔ／、〆Ｈ導入した。操業開始１５分経過後はソ
定常状態に達し、第３反応槽の塩素ガス流量は平均１，
８Ｎｎ？／Ｈで全塩素ガス流針は平均１８．３　Ｎｒｒ
？／Ｈであった。On the other hand, ORP Ex is 735 mV (effective chlorine concentration 98
．． 0μ equivalent) and chlorine gas (purity 96.7%).
) to 1st reaction tank 1, 11.0V shoulder, 5th to 2nd reaction tank 2
．． 5Nt/, H was introduced. After 15 minutes from the start of operation, a steady state is reached, and the average flow rate of chlorine gas in the third reaction tank is 1,
8Nn? /H, total chlorine gas flow needle averages 18.3 Nrr
? /H.

製造は２時間継続したが、各反応槽液面上の雰囲気の塩
素ガス濃度は４　ｐｐｍ以下で、懸濁残渣１．３チを含
む、有効塩素温度約９８　ｆ／Ｌのさらし液を６３　Ｂ
、　５　ｋｓ＋／Ｈが得られた。The production continued for 2 hours, and the chlorine gas concentration in the atmosphere above the liquid surface of each reactor was 4 ppm or less, and the exposed solution containing 1.3 cm of suspended residue and an effective chlorine temperature of about 98 f/L was heated to 63 B.
, 5 ks+/H was obtained.

製造終了時の第１、第２反応槽の反応溶液中の有効塩素
濃度は５８．３　ｔ／ｌ、　８　Ｂ、　２　ｆ／ｌで塩
素収率は９５．７チであった。At the end of production, the effective chlorine concentration in the reaction solution in the first and second reaction vessels was 58.3 t/l, 8 B, 2 f/l, and the chlorine yield was 95.7 t/l.

比較例 攪拌機を備えた容積１−のポリエチレン製タンクに純度
９３．８％の消石灰を水中に投入し、攪拌機、循環ポン
プで循環混合し、スラリー濃度１１．８重量％の石灰乳
液８００ｔを調製した。Comparative Example Slaked lime with a purity of 93.8% was put into water in a 1-volume polyethylene tank equipped with an agitator, and circulated and mixed using an agitator and a circulation pump to prepare 800 tons of lime emulsion with a slurry concentration of 11.8% by weight. .

次に純度９６．７　％の塩素ガスを石灰乳液に吹込んだ
。塩素ガスを通した当初は液面に未反応塩素ガスが極め
て多いので０．８　Ｎｄ１Ｈで吹込み、未反応塩素ガス
濃度が１０　ｐｐｍを超えない範囲で、逐次吹込み塩素
ガス流量を増加させた。Next, 96.7% pure chlorine gas was blown into the lime emulsion. Initially, when chlorine gas was passed through, there was an extremely large amount of unreacted chlorine gas on the liquid surface, so 0.8 Nd1H was blown into the liquid, and the flow rate of chlorine gas was gradually increased until the concentration of unreacted chlorine gas did not exceed 10 ppm. .

反応中間段階では最高１３　Ｎｒｒ？ｌＨ迄吹込んだが
、反応の終点近くでは再び未反応塩素ガスが増加するの
で９　Ｎｍｌ／Ｈに低下させた。この結果、反応時間９
時間１２分要し、懸濁残渣１．３係含む有効塩素濃度９
７．９　ｔ／Ｌのさらし液９１９．４ｋｆを得た。Up to 13 Nrr in the middle stage of the reaction? Although it was blown in to 1H, the amount of unreacted chlorine gas increased again near the end of the reaction, so it was lowered to 9 Nml/H. As a result, the reaction time was 9
It takes 12 minutes and the effective chlorine concentration is 9, including 1.3 parts of suspended residue.
919.4 kf of a bleaching solution of 7.9 t/L was obtained.

又、その途中の有効塩素濃度４０　ｆ／ｌに達する迄に
７時間を要しておシ、塩素収率Ｆ１９３．５１であし極
めて生産性が悪いものであった。Further, it took 7 hours to reach the effective chlorine concentration of 40 f/l, and the chlorine yield was F193.51, resulting in extremely poor productivity.

【図面の簡単な説明】[Brief explanation of the drawing]

矛１図は本発明方法を実施する装置の１例を示したもの
である。 ４は石灰乳液貯槽、１．２は第１段反応帯域に相当する
第１反応槽、り・２反応槽、３は牙２段反応帯域に相当
する第３反応槽、Ｃｔ　、　Ｃｔ　、　Ｃ３は各反応槽
の冷却用熱交換器、Ｐｔ　、　Ｐｓ　、　Ｐｓ　、　Ｐ
４循環送液ポンプ、Ｅ、　、　Ｅ、　、　Ｅ３は酸化還
元電位の検知器、Ｌ、、Ｌ、、Ｌ、はレベル計、ｖｌ、
　ｖ、　、　Ｖｓはレベル計と連動して送液する自動弁
、２０．２１は塩素ガスの導入パルプ、ｖ４はＥ、によ
り連動する塩素ガス自動弁、ＦＨ’　＋　Ｆｔ　＊　Ｆ
ｓは塩素ガス流量側、５はさらし液貯槽を示す。Figure 1 shows an example of an apparatus for carrying out the method of the present invention. 4 is a lime emulsion storage tank, 1.2 is the first reaction tank corresponding to the first stage reaction zone, Ri-2 reaction tank, 3 is the third reaction tank corresponding to the second stage reaction zone, Ct, Ct, C3 are Cooling heat exchanger for each reaction tank, Pt, Ps, Ps, P
4 circulation liquid pump, E, , E, , E3 is a redox potential detector, L, , L, , L is a level meter, vl,
v, , Vs is an automatic valve that sends liquid in conjunction with a level meter, 20.21 is a chlorine gas introduction pulp, v4 is an automatic chlorine gas valve that is synchronized with E, FH' + Ft * F
s indicates the chlorine gas flow rate side, and 5 indicates the exposure liquid storage tank.

Claims (1)

【特許請求の範囲】[Claims] １）石灰乳液と塩素ガスより、次亜塩素酸カルシウムを
主成分とするさらし液を製造する方法に於いて、該製造
に於ける反応帯域を２段に分け各段に塩素ガスを分割し
て導入し、且つ、該第１段反応帯域においての該反応溶
液中の有効塩素濃度は４０〜１００ｇ／ｌを常に保持す
るよう導入石灰乳液及び塩素ガスを調節し、該第２段反
応帯域では所望の有効塩素濃度に該塩素化反応を完結せ
しめることを特徴とするさらし液の連続製造法。1) In a method for producing a bleaching solution containing calcium hypochlorite as a main component from lime emulsion and chlorine gas, the reaction zone in the production is divided into two stages, and the chlorine gas is divided into each stage. The introduced lime emulsion and chlorine gas are adjusted so that the effective chlorine concentration in the reaction solution in the first stage reaction zone is always maintained at 40 to 100 g/l, and the lime emulsion and chlorine gas are adjusted to maintain the effective chlorine concentration in the reaction solution in the first stage reaction zone. 1. A method for continuous production of a bleaching solution, characterized in that the chlorination reaction is completed at an effective chlorine concentration of .