JPS63147502A - Crystallizing and refining method - Google Patents
Crystallizing and refining methodInfo
- Publication number
- JPS63147502A JPS63147502A JP29496486A JP29496486A JPS63147502A JP S63147502 A JPS63147502 A JP S63147502A JP 29496486 A JP29496486 A JP 29496486A JP 29496486 A JP29496486 A JP 29496486A JP S63147502 A JPS63147502 A JP S63147502A
- Authority
- JP
- Japan
- Prior art keywords
- tube
- crystal
- tubes
- jacket
- mother liquor
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims description 15
- 238000007670 refining Methods 0.000 title abstract 2
- 239000013078 crystal Substances 0.000 claims abstract description 41
- 238000002425 crystallisation Methods 0.000 claims abstract description 13
- 230000008025 crystallization Effects 0.000 claims abstract description 13
- 239000012452 mother liquor Substances 0.000 claims abstract description 11
- 239000002826 coolant Substances 0.000 claims description 11
- 238000000746 purification Methods 0.000 claims description 9
- 239000000203 mixture Substances 0.000 claims description 3
- 238000011084 recovery Methods 0.000 abstract description 5
- 238000002844 melting Methods 0.000 abstract description 2
- 230000008018 melting Effects 0.000 abstract description 2
- 239000003507 refrigerant Substances 0.000 abstract 1
- UFWIBTONFRDIAS-UHFFFAOYSA-N Naphthalene Chemical compound C1=CC=CC2=CC=CC=C21 UFWIBTONFRDIAS-UHFFFAOYSA-N 0.000 description 21
- 239000012071 phase Substances 0.000 description 6
- 239000002994 raw material Substances 0.000 description 5
- 239000000498 cooling water Substances 0.000 description 3
- 239000007791 liquid phase Substances 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- FCEHBMOGCRZNNI-UHFFFAOYSA-N 1-benzothiophene Chemical compound C1=CC=C2SC=CC2=C1 FCEHBMOGCRZNNI-UHFFFAOYSA-N 0.000 description 2
- CWRYPZZKDGJXCA-UHFFFAOYSA-N acenaphthene Chemical compound C1=CC(CC2)=C3C2=CC=CC3=C1 CWRYPZZKDGJXCA-UHFFFAOYSA-N 0.000 description 2
- NIHNNTQXNPWCJQ-UHFFFAOYSA-N fluorene Chemical compound C1=CC=C2CC3=CC=CC=C3C2=C1 NIHNNTQXNPWCJQ-UHFFFAOYSA-N 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 230000000717 retained effect Effects 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- HXGDTGSAIMULJN-UHFFFAOYSA-N acetnaphthylene Natural products C1=CC(C=C2)=C3C2=CC=CC3=C1 HXGDTGSAIMULJN-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- TXCDCPKCNAJMEE-UHFFFAOYSA-N dibenzofuran Chemical compound C1=CC=C2C3=CC=CC=C3OC2=C1 TXCDCPKCNAJMEE-UHFFFAOYSA-N 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000005243 fluidization Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 125000001624 naphthyl group Chemical group 0.000 description 1
- 239000012264 purified product Substances 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Abstract
Description
【発明の詳細な説明】
(産業上の利用分野)
本発明は、晶析精製方法に関する。詳しく述べると、結
晶の回収率が高くかつ安定な晶析精製方法に関する。DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a crystallization purification method. More specifically, the present invention relates to a crystallization purification method that provides a high crystal recovery rate and is stable.
(従来の技術)
上下2段の横置き型チューブおよび垂直型チューブの3
つのチューブで形成された晶析ti %’J 装置は、
特公昭54−34.705号公報に記載されている。(Conventional technology) 3 horizontal tubes and vertical tubes with upper and lower tiers
The crystallization ti %'J apparatus formed of two tubes is
It is described in Japanese Patent Publication No. 54-34.705.
この公報では、連結部を介して接続された2段の横置き
型チューブ■およびIIをチューブIからIIへ連続的
熱抽出によって温度勾配を設けること、各セクションに
おける液相中の懸濁系をなす結晶相を撹拌手段および液
体流速度の厳密な制御により沈降と流動化との中間状態
に維持させながら、固体−液体を連続向流接触させるこ
とによって晶析精製することを特徴としている。しかし
ながら、この方法では、結晶相と液相の密度が温度の影
響で変動する場合には運転が非常に困難となる。In this publication, a temperature gradient is created by continuous thermal extraction from tube I to tube II in two horizontally placed tubes ■ and II connected via a connecting part, and a suspension system in the liquid phase in each section is It is characterized by crystallization and purification by bringing the solid-liquid into continuous countercurrent contact while maintaining the resulting crystalline phase in an intermediate state between sedimentation and fluidization by stirring means and strict control of the liquid flow rate. However, this method becomes very difficult to operate if the densities of the crystalline phase and liquid phase vary due to the influence of temperature.
すなわち、一般に結晶は母液より重く、また溶液は低温
になるほど密度が高いが、上段側に92けられ、母液J
友出口があるチューブIIはより低温に保たれ、密度を
高くされることになるので、チューブIIより高温に保
たれ、下段側に設けられたチューブ■との間に対流が生
じやすく、これにより急激な結晶の生成や結晶の固着等
を引き起すことになる。結晶の固着が増大すると、スク
レーパコンベアの回転トルクが上昇し運転不能をもたら
す。In other words, the crystals are generally heavier than the mother liquor, and the lower the temperature of the solution, the higher the density.
Tube II, which has a friend exit, is kept at a lower temperature and has a higher density, so it is kept at a higher temperature than Tube II, and convection is likely to occur between it and Tube ■, which is installed on the lower side. This may cause the formation of crystals or the fixation of crystals. As the crystal adhesion increases, the rotational torque of the scraper conveyor increases, resulting in an inoperable state.
これを防止するためには、チューブIIの冷却をゆるめ
、過剰の結晶をチューブflへためない運転をすること
が考えられるが、この方法では結晶の回収率を犠牲にす
ることになる。In order to prevent this, it is conceivable to loosen the cooling of tube II and operate the tube in such a way that excess crystals are not stored in tube fl, but this method sacrifices the crystal recovery rate.
(発明が解決しようとする問題点)
本発明は、結晶の回収率を高く維持しつつ、安定に晶析
精製を行うことのできる方法を提供することを目的とす
る。(Problems to be Solved by the Invention) An object of the present invention is to provide a method capable of stably performing crystallization and purification while maintaining a high recovery rate of crystals.
く問題点を解決するための手段)
本発明は、内部にスクレーパーコンベアを有しかつ外部
に冷却媒体を流すためのジャケットが設けられた上下2
段の第1および第2の横置き型チューブが一端で泪互に
連結部を介して接続され、かつ第2のチューブの末端側
には母液抜出口が52けられ、第1のチューブの他端側
は下部に結晶J友出口を有する垂直に置かれた竪型チュ
ーブの上部に連結部を介して接続されてなる晶析精製装
置に導入された結晶性成分を含む混合物中の少なくとも
一成分を晶析分離する方法において、第1および第2の
チューブ内にある結晶層の上部位置が少なくとも中心軸
面より上となるようにするとともに、第1のチューブに
おける結晶層を形成している結晶相の割合が第2のチュ
ーブにあける結晶相の割合より同等ないし高くなるよう
に保持する晶析精製方法である。Means for Solving the Problems) The present invention provides upper and lower parts having a scraper conveyor inside and a jacket for flowing a cooling medium to the outside.
The first and second horizontal tubes of the stage are connected to each other at one end through a connecting part, and the second tube has 52 mother liquor outlet ports on the distal end side, and At least one component in a mixture containing crystalline components introduced into a crystallization purification device, the end of which is connected via a connection to the top of a vertically placed vertical tube having a crystal outlet at the bottom. In a method for crystallizing and separating a This is a crystallization purification method in which the phase ratio is maintained to be equal to or higher than the crystal phase ratio in the second tube.
(作用)
つぎに、図面を参照しながら本発明方法をざらに詳細に
説明する。すなわち、図面から明らかなように、本発明
において使用する晶析′債製装首は、内部にスクレーパ
ーコンベアからなる結晶搬送手段を有し、外部には冷却
媒体を流すジャケットが設けられた上下二段の第1およ
び第2の水平横置き型チューブIおよびIIと、内部に
撹拌手段と下部に結晶融解のためのスチームヒーター等
の加熱手段1を備えた竪型のチューブ川とがそれぞれ連
結部2,3により連通したものである。そして、第2の
チューブ11は第1のチューブ■の上段側に位置し、第
1のチューブエとの連結部の他端側には母液抜出口4が
設けられてあり、また第1のチューブ■の他端側には、
竪型チューブ用の上部と連結部3を介して接続している
。(Operation) Next, the method of the present invention will be roughly explained in detail with reference to the drawings. That is, as is clear from the drawings, the crystallization bond-making neck used in the present invention has an internal crystal conveying means consisting of a scraper conveyor, and an upper and lower upper jacket provided with a jacket for flowing a cooling medium on the outside. The first and second horizontally placed tubes I and II of the stage and the vertical tube river equipped with stirring means inside and heating means 1 such as a steam heater for crystal melting at the bottom are connected to each other. 2 and 3 communicate with each other. The second tube 11 is located on the upper side of the first tube (2), and a mother liquor outlet 4 is provided at the other end of the connecting portion with the first tube (2). On the other end of
It is connected to the upper part of the vertical tube via a connecting part 3.
原料混合物は、第1のチューブIの中間部または第2の
チューブII若しくは竪型チューブIIIとの連結部付
近の原料供給口5から導入され、外部ジャケットで冷却
され、母液抜出口4に向かって温度が低下するように温
度勾配がδ2けられた第1のチューブ■および第2のチ
ューブJlを流れる間に結晶を析出し、母液が1友出口
4から扱き出される。The raw material mixture is introduced from the raw material supply port 5 near the middle part of the first tube I or the connection part with the second tube II or vertical tube III, is cooled by an external jacket, and then flows toward the mother liquor outlet 4. Crystals are precipitated while flowing through the first tube (3) and the second tube (J1) in which the temperature gradient is set by δ2 so as to reduce the temperature, and the mother liquor is discharged from the first tube (4).
析出した結晶はスクレーパーコンベアにより母液と向流
するように移送され、竪型のチューブIIIの下部で融
解されて結晶(友出口6から扱き出されろ。The precipitated crystals are transferred by a scraper conveyor so as to flow countercurrently to the mother liquor, and are melted at the bottom of the vertical tube III, and the crystals are removed from the outlet 6.
本発明においては、第1および第2のチューブエおよび
IIに結晶層の上部位置を少なくとも中心軸面より上と
なるように、好ましくはスクレーパーコンベアの運転等
に支障がない限りてきるだけ上部に保持するとともに第
1のチューブ■にあける結晶層の割合が第2のチューブ
IIにおける割合と同等ないしはそれより高くなるよう
に保持する。In the present invention, the upper position of the crystal layer in the first and second tubes and II is held at least above the central axis plane, preferably as high as possible as long as it does not interfere with the operation of the scraper conveyor, etc. At the same time, the ratio of the crystal layer formed in the first tube (2) is maintained to be equal to or higher than the ratio in the second tube (II).
好ましくは第1のチューブ■にあける結晶、苦の上部位
置は、断面高さの1/2〜475程度となるように保持
する。第2のチューブIIにおける結晶層の上部位置は
、gJT面高さの172〜273程度となるように保持
するが、この断面高さはチューブエのそれより同等かい
くらか低い位置とすることが望ましい。なお、本発明で
いう結晶層の上部位置は結晶スラリーからなる結晶相と
母液相との界面位置をいう。Preferably, the upper position of the crystal hole drilled in the first tube (2) is maintained at about 1/2 to 475 mm of the cross-sectional height. The upper position of the crystal layer in the second tube II is maintained at about 172 to 273 of the gJT surface height, but it is desirable that this cross-sectional height is equal to or somewhat lower than that of the tube. Note that the upper position of the crystal layer in the present invention refers to the interface position between the crystal phase consisting of crystal slurry and the mother liquid phase.
この制御は第1および第2デユープ■およびIIのジャ
ケラl゛−に流す冷却媒体の温度および流」を制御する
ことによって行うことができるか、第1および第2のチ
ューブ■と工1における結晶相の01合を独立して制御
するために、各々のチューブのジャケットに流す冷却媒
体は独立して温度および流量を調整することができるよ
うにしておくことが望ましい。This control can be performed by controlling the temperature and flow of the cooling medium flowing through the jackets of the first and second tubes (1) and (2), or In order to independently control the phase ratio, it is desirable to be able to independently adjust the temperature and flow rate of the cooling medium flowing through the jacket of each tube.
好ましくは、第2のチューブUの外部ジャケットに流す
第2の冷却媒体の温度および流量は独立して制御すると
ともに、第2の冷却媒体は第2のチューブIIの母液投
出口4附近のジャケットより流入させ、第2のチューブ
IIの他端より排出させる。第1の冷却媒体は下段の第
1のチューブIの第2のチューブIIどの連結部2附近
のジャケットより流入させ、他端より排出させる。この
とき第1の冷却媒体と、第2の冷加媒体の流入温度には
差異を設けるが、原料が95%ナフタリン油の場合温度
差は4°C以上、好ましくは6℃前後、第2の冷却媒体
の流入温度を低く保持する。Preferably, the temperature and flow rate of the second cooling medium flowing into the external jacket of the second tube U are independently controlled, and the second cooling medium is supplied from the jacket near the mother liquor outlet 4 of the second tube II. It is made to flow in and discharged from the other end of the second tube II. The first cooling medium is caused to flow into the jacket of the second tube II of the first tube I in the lower stage near which connecting portion 2, and is discharged from the other end. At this time, a difference is provided between the inflow temperatures of the first cooling medium and the second cooling medium, but if the raw material is 95% naphthalene oil, the temperature difference is 4°C or more, preferably around 6°C, Keep the coolant inlet temperature low.
本発明方法では、第1および第2のチューブIおよびチ
ューブ11における結晶層の上部位置、すなわち結晶の
保持量を高くするとともに、第2のチューブIfにおけ
る結晶の保持量を第1のチューブ■におけるそれ以下に
したので、見掛比重の差の増大および対流の増大が防止
できるものと考えられる。In the method of the present invention, the upper position of the crystal layer in the first and second tubes I and tube 11, that is, the amount of crystals retained, is increased, and the amount of crystals retained in the second tube If is increased in the first tube ■. It is considered that by setting the temperature to be less than that, an increase in the difference in apparent specific gravity and an increase in convection can be prevented.
(実施例)
以下、実施例を挙げて本発明方法をさらに詳細に説明す
る。なお、下記実施例における「部」は、特にことわら
ない限り重量部である。(Example) Hereinafter, the method of the present invention will be explained in more detail with reference to Examples. In addition, "parts" in the following examples are parts by weight unless otherwise specified.
実施例
図面に示すように、内部にリボン型撹拌機を、外部に冷
却水を流すジャケットを備えた第1および第2の横置き
型チューブI、IIが一端で連結部2を介して連結して
上下に配置され、かつ下段の第1のチューブIの他端が
、棒状撹拌器を内蔵する竪型チューブIIIの上部に連
結されてなる三塔式品析装置を使用してタール系95%
ナフタリンを毎時100部の割合で下段の第1のチュー
ブ■の中間位置の原料供給口5から装入した。下段の第
1のチューブ■のジャケットに39°Cに設定した冷却
水を流し出口温度48°Cで排出させることでチューブ
I内にナフタリン結晶を蓄積させた。次いで、上段の第
2のチューブIIのジャケットには33°Cに設定した
冷却水を流し、出口温度40’Cで排出させることで、
第2のチューブII内にもナフタリン結晶を蓄積させた
。ナフタリン結晶層の界面位置は上段の第2のチューブ
II側は断面高さの約375の位置に、一方、下段の第
1のチューブ■側では断面高さの約374の位置に安定
した。竪型チューブIIIの底部にあるスチームヒータ
ーによりナフタリン結晶を溶融して高純度に精製された
製品を後き出し、一方、上段第2のチューブIIの他端
にある母液J友出口4からは不純物であるチオナフテン
が濃縮された母液を抜き出した。As shown in the drawings, first and second horizontal tubes I and II, each equipped with a ribbon-type stirrer inside and a jacket for flowing cooling water outside, are connected at one end through a connecting part 2. Using a three-column type product analyzer, which is arranged one above the other, and the other end of the lower first tube I is connected to the upper part of the vertical tube III containing a rod-shaped stirrer, tar-based 95%
Naphthalene was charged at a rate of 100 parts per hour from the raw material supply port 5 located in the middle of the first tube (2) in the lower stage. Naphthalene crystals were accumulated in tube I by flowing cooling water set at 39°C through the jacket of the first tube (1) in the lower stage and discharging it at an outlet temperature of 48°C. Next, cooling water set at 33°C was flowed through the jacket of the second tube II in the upper stage, and the water was discharged at an outlet temperature of 40'C.
Naphthalene crystals also accumulated in the second tube II. The interface position of the naphthalene crystal layer was stabilized at a position of about 375 of the cross-sectional height on the second tube II side in the upper stage, and at a position of about 374 of the cross-sectional height on the side of the first tube II in the lower stage. The naphthalene crystals are melted by the steam heater at the bottom of the vertical tube III and a highly purified product is discharged, while impurities are discharged from the mother liquor outlet 4 at the other end of the upper second tube II. A mother liquor enriched with thionaphthene was extracted.
このような状況下では、晶析状況はまったく安定してお
り、このときの原料95%ナフタリンの装入量が毎時1
00部に対し、竪型チューブInの底部から、は製品と
して毎時80部の高純度ナフタリン(FP79.79℃
、ナフタリン分99.6%)が、一方、上段の第2のチ
ューブIIの母液抜出口4からは毎時20部の残油(F
P71.0’C。Under these conditions, the crystallization situation is completely stable, and the charging amount of raw material 95% naphthalene at this time is 1 hourly.
00 parts per hour, from the bottom of the vertical tube In, 80 parts per hour of high purity naphthalene (FP79.79°C) is produced as a product.
, naphthalene content: 99.6%), while 20 parts of residual oil (F
P71.0'C.
ナフタリン分82%チオナフテン分10%)が(友き出
せた。したがって製品歩留は80%に達した。The naphthalene content was 82% and the thionaphthene content was 10%. Therefore, the product yield reached 80%.
(発明の効果)
以上述べたように本発明の方法によれば、結晶の回収率
を高く維持しつつ、安定に晶析精製を行なうことができ
るので、タール系の各留分なと結晶成分を含む各種留分
よりナフタリン、ジフェニレンオキサイド、フルオレン
、アセナフテン等の結晶成分を極めて高純度で、しかも
高収率で運、続的に得ることが可能となる。(Effects of the Invention) As described above, according to the method of the present invention, it is possible to stably perform crystallization purification while maintaining a high recovery rate of crystals. It becomes possible to continuously obtain crystalline components such as naphthalene, diphenylene oxide, fluorene, and acenaphthene with extremely high purity and high yield from various fractions containing .
図面は、本発明方法の一実施例を示すフローシートであ
る。
図中、1.IIおよびIIIはチューブである。
特許出願人 新日鐵化学株式会社((よ7)X
−1石ンThe drawing is a flow sheet showing one embodiment of the method of the present invention. In the figure, 1. II and III are tubes. Patent applicant: Nippon Steel Chemical Co., Ltd. ((yo7)X
-1 stone
Claims (1)
を流すためのジャケットが設けられた上下2段の第1お
よび第2の横置き型チューブが一端で相互に連結部を介
して接続され、かつ第2のチューブの末端側には母液抜
出口が設けられ、第1のチューブの他端側は下部に結晶
抜出口を有する垂直に置かれた竪型チューブの上部に連
結部を介して接続されてなる晶析精製装置に導入された
結晶性成分を含む混合物中の少なくとも一成分を晶析分
離する方法において、第1および第2のチューブ内にあ
る結晶層の上部位置が少なくとも中心軸面より上となる
ようにするとともに、第1のチューブにおける結晶層を
形成している結晶相の割合が第2のチューブにおける結
晶相の割合より同等ないし高くなるように保持すること
を特徴とする晶析精製方法。The first and second horizontally placed tubes in two stages (upper and lower) each having a scraper conveyor inside and a jacket for flowing a cooling medium to the outside are connected to each other at one end through a connecting part, and A mother liquor outlet is provided at the end of the second tube, and the other end of the first tube is connected via a connecting portion to the top of a vertically placed vertical tube having a crystal outlet at the bottom. In a method for crystallizing and separating at least one component in a mixture containing crystalline components introduced into a crystallization purification apparatus, the upper positions of the crystal layers in the first and second tubes are at least above the central axis plane. Crystallization purification characterized by maintaining the ratio of the crystal phase forming the crystal layer in the first tube to be equal to or higher than the ratio of the crystal phase in the second tube. Method.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP29496486A JPS63147502A (en) | 1986-12-12 | 1986-12-12 | Crystallizing and refining method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP29496486A JPS63147502A (en) | 1986-12-12 | 1986-12-12 | Crystallizing and refining method |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS63147502A true JPS63147502A (en) | 1988-06-20 |
Family
ID=17814578
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP29496486A Pending JPS63147502A (en) | 1986-12-12 | 1986-12-12 | Crystallizing and refining method |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS63147502A (en) |
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1986
- 1986-12-12 JP JP29496486A patent/JPS63147502A/en active Pending
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