JPH07178301A - Method for distilling multicomponent mixture - Google Patents

Method for distilling multicomponent mixture

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Publication number
JPH07178301A
JPH07178301A JP32717793A JP32717793A JPH07178301A JP H07178301 A JPH07178301 A JP H07178301A JP 32717793 A JP32717793 A JP 32717793A JP 32717793 A JP32717793 A JP 32717793A JP H07178301 A JPH07178301 A JP H07178301A
Authority
JP
Japan
Prior art keywords
distillate
distillation
composition
amount
temp
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
Application number
JP32717793A
Other languages
Japanese (ja)
Inventor
Muneki Hirao
宗樹 平尾
Haruo Sawada
晴男 澤田
Kaoru Onoda
薫 小野田
Yasunaga Endo
泰永 遠藤
Susumu Ide
進 井出
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kao Corp
Original Assignee
Kao Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Kao Corp filed Critical Kao Corp
Priority to JP32717793A priority Critical patent/JPH07178301A/en
Publication of JPH07178301A publication Critical patent/JPH07178301A/en
Pending legal-status Critical Current

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  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)

Abstract

PURPOSE:To improve the firmness and wide applicability of control regardless of the disturbance such as variations in the supply of raw material and its composition by cascade-controlling the deviation of the detected temp. or temp. difference in a tower from the preset temp. or temp. difference against the distillate amt. set from the material balance. CONSTITUTION:The temp. difference obtained from the temp. detectors 31 and 32 provided in a distillation tower 1 with a substracter 103 is used as the measured value and the preset temp. difference as the target value, and both values are outputted to a PID controller 113. A plus signal is added in the controller 113 when the measured value is smaller than the target value, a minus signal is added when the measured value is larger, and the signal is outputted to an adder 101. The sum of the distillate amt. of a specified composition calculated by a material balance computing element 125 and the output value of the signal obtained by the controller 113 is outputted to a distillate flowmeter 23 as the target value from the adder 101, and the distillate amt. of the specified component is controlled by the flowmeter 23.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は多成分系混合物の蒸留方
法、更に詳しくは、多成分系混合物から所定の組成物を
蒸留分離する多成分系混合物の蒸留方法に関する。
FIELD OF THE INVENTION The present invention relates to a method for distilling a multi-component mixture, and more particularly to a method for distilling a predetermined composition from a multi-component mixture by distillation.

【0002】[0002]

【従来の技術及び発明が解決しようとする課題】多成分
系混合物の連続蒸留は、化学工業等において多用されて
いる単位操作であり、一般的に、蒸留に用いられる蒸留
塔の制御は、混合物から所定の組成物(留出物)及び缶
出物を最小のエネルギーで分離することを目的としてい
る。例えば、ヤシ油やパーム核油等の天然油脂から誘導
される脂肪酸、メチルエステル、高級アルコール等は、
炭素数6から20の偶数アルキル鎖長をもつ8成分以上
の多成分系混合物であり、これらの多成分系混合物か
ら、高純度の単一アルキル鎖長の組成物(留出物)を連
続的に分離する場合、少なくとも7基の蒸留塔を直列に
又は並列に連結し、原料の供給流量の変動やその組成の
変動等の外乱に対して留出物の純度を一定に維持するよ
うに、これらの蒸留塔を制御することが必要である。
BACKGROUND OF THE INVENTION Continuous distillation of a multi-component mixture is a unit operation frequently used in the chemical industry and the like. Generally, the control of a distillation column used for distillation is to control the mixture. It is intended to separate a given composition (distillate) and bottoms from the product with minimum energy. For example, fatty acids derived from natural oils and fats such as palm oil and palm kernel oil, methyl esters, higher alcohols, etc.
It is a multi-component mixture of 8 or more components having an even alkyl chain length of 6 to 20 carbon atoms, and from this multi-component mixture, a high-purity single alkyl chain length composition (distillate) is continuously obtained. In the case of separating into 2, the distillation columns of at least 7 units are connected in series or in parallel, so as to maintain the purity of the distillate constant against disturbances such as fluctuations in the feed flow rate of raw materials and fluctuations in its composition, It is necessary to control these distillation columns.

【0003】一方、蒸留プロセスは、(1)強い干渉系
である、(2)非線形性が強い、(3)比較的遅い時間
の応答形であるという特徴を有するため、複数の蒸留塔
を連結した装置構成において、各蒸留塔における特定成
分の留出液と缶出液とへの分配を制御すること、即ち、
両端組成を制御することは、非常に困難である。
On the other hand, the distillation process is characterized by (1) a strong interference system, (2) strong non-linearity, and (3) a relatively slow response time, so that a plurality of distillation columns are connected. In the device configuration described above, controlling the distribution of the specific component into the distillate and the bottom liquid in each distillation column, that is,
It is very difficult to control the composition at both ends.

【0004】このため、一般的に、上記のような多成分
系混合物から単一アルキル鎖長の組成物(留出物)を分
離をする場合、先ず、混合物からなる3ないし4留分に
大別し、これらの留分を再度蒸留して各単一組成物(留
出物)を得る方法が用いられている。しかしながら、こ
の方法では、同一組成物を2回蒸留するため、エネルギ
ー消費が多く、且つ、得られる製品の品質が長い熱履歴
のために劣化したり、製品の一部が初留カット等により
損失するという問題があった。
Therefore, in general, when separating a composition (distillate) having a single alkyl chain length from the above-mentioned multi-component mixture, first, a large amount is divided into 3 to 4 fractions consisting of the mixture. Separately, a method of distilling these fractions again to obtain each single composition (distillate) is used. However, in this method, since the same composition is distilled twice, it consumes a lot of energy, and the quality of the obtained product deteriorates due to a long heat history, or a part of the product is lost due to initial distillation cut or the like. There was a problem of doing.

【0005】また、蒸留塔における両端組成を制御する
方法については、従来から、種々の方法が知られてお
り、例えば、オンライン成分分析計によって留出液及び
缶出液の組成を直接制御する方法については、特公平4
−68961号公報に、また、温度を利用したモデル予
測手法によって留出液及び缶出液の組成を制御する方法
については、特開平3−109902号公報に、また、
蒸留塔内温度を留出量及び/又はリボイラー加熱媒体の
伝熱量に対してカスケード制御することにより留出液及
び缶出液の組成を制御する方法については、特公平5−
68283号公報にそれぞれ記載されている。
Various methods have been conventionally known for controlling the composition at both ends of a distillation column. For example, a method for directly controlling the composition of distillate and bottoms by an online component analyzer. About,
-68961, and a method for controlling the composition of distillate and bottoms by a model prediction method using temperature, see JP-A-3-109902,
Regarding the method for controlling the composition of the distillate and the bottoms by cascade controlling the temperature in the distillation column with respect to the amount of distillate and / or the amount of heat transfer of the reboiler heating medium, see Japanese Patent Publication No.
No. 68283, respectively.

【0006】しかしながら、特公平4−68961号公
報及び特公平5−68283号公報それぞれに記載され
た両端組成制御の方法は、制御対象が1つの蒸留塔のみ
に関するものであり、複数の蒸留塔を制御する制御機構
を有していないため、上流側の蒸留塔で外乱が生じた場
合、その直後にある蒸留塔へ流入する上流側の蒸留塔の
缶出物中の限界低沸点成分は制御し難いという問題があ
る。
However, the methods for controlling the composition at both ends described in JP-B-4-68961 and JP-B-5-68283 relate to only one distillation column to be controlled, and a plurality of distillation columns cannot be used. Since there is no control mechanism to control, when disturbance occurs in the distillation column on the upstream side, the limit low boiling point component in the bottom product of the distillation column on the upstream side that flows into the distillation column immediately after that is controlled. There is a problem of difficulty.

【0007】また、特開平3−109902号公報に記
載された両端組成制御の方法は、モデル予測パラメータ
ーを決定するのに長時間の試運転を要し、且つ、プラン
ト毎にそのパラメーターを求めなければならないため、
汎用性に劣るという問題がある。
Further, the method of controlling both-end composition disclosed in Japanese Patent Laid-Open No. 3-109902 requires a long trial run to determine model prediction parameters, and the parameters must be obtained for each plant. Because it does not
There is a problem of poor versatility.

【0008】従って、本発明の目的は、上述の問題を解
決した蒸留方法、即ち、原料の供給流量の変動やその組
成の変動等の外乱に拘わらず、制御の堅固性(制御モデ
ルの構造やパラメーターの変動に対する制御性能の保持
性)に優れ且つ汎用性に優れた多成分系混合物の蒸留方
法を提供することにある。
Therefore, an object of the present invention is to provide a distillation method that solves the above-mentioned problems, that is, robustness of control (structure of the control model and structure of control model) It is an object of the present invention to provide a distillation method for a multi-component system mixture, which has excellent controllability with respect to fluctuations in parameters) and versatility.

【0009】[0009]

【課題を解決するための手段】本発明は、複数の蒸留塔
を用い、多成分系混合物から所定の組成物を連続的に分
離する方法であって、(1)少なくとも3基以上の蒸留
塔を直列に又は直列と並列とに連結した装置構成であっ
て、(2)最初の蒸留塔に供給される原料の供給流量及
びその組成を周期的に検出し、この検出結果に基づい
て、物質収支を演算することにより、各々の蒸留塔から
留出する上記組成物の留出量を同時に設定し、(3)検
出した塔内の温度又は温度差と、予め設定した塔内の温
度又は温度差との偏差を、上記物質収支より設定した上
記留出量に対してカスケード制御することを特徴とする
多成分系混合物の蒸留方法を提供することにより、上記
目的を達成したものである。
The present invention is a method for continuously separating a predetermined composition from a multi-component mixture using a plurality of distillation columns, which comprises (1) at least three distillation columns. Is connected in series or in series and in parallel, and (2) the supply flow rate of the raw material supplied to the first distillation column and its composition are periodically detected, and based on this detection result, the substance is detected. By calculating the balance, the amount of the above-mentioned composition distilled from each distillation column is set at the same time, and (3) the detected temperature or temperature difference in the column and the preset temperature or temperature in the column The object is achieved by providing a distillation method for a multi-component mixture, which is characterized in that the deviation from the difference is cascade-controlled with respect to the distillation amount set based on the material balance.

【0010】本発明の多成分系混合物の蒸留方法におい
て、最も重要な点は、最初の蒸留塔に供給される原料の
供給流量(単位時間当りの供給量)及びその組成を用い
て一義的に複数の蒸留塔の留出量を定める点にあり、複
数の蒸留塔を同時に制御することにより、1つの蒸留塔
における干渉性と連結される蒸留塔間の干渉性を同時に
防止することができる。
In the distillation method of the multi-component mixture of the present invention, the most important point is uniquely using the feed flow rate (feed amount per unit time) of the raw material fed to the first distillation column and its composition. The point is to determine the amount of distillate of a plurality of distillation columns, and by controlling the plurality of distillation columns at the same time, it is possible to prevent the coherence in one distillation column and the coherence between connected distillation columns at the same time.

【0011】多成分系混合物を蒸留分離するための装置
構成は、特に制限されず、例えば各塔を直列に又は直列
と並列とに連結して構成することができる(図1及び図
2参照)。本発明の多成分系混合物の蒸留方法において
用いられる蒸留塔は、その型式には制限されないが、製
品の熱履歴をできるだけ少なくするため及び外乱に対す
る応答性をできるだけ速くするために、塔内での原料の
滞留量が少ない型式のものが好ましく、その代表的なも
のとして、充填塔型蒸留塔が挙げられる。
The apparatus structure for separating the multi-component system mixture by distillation is not particularly limited, and for example, each column can be connected in series or in series and parallel (see FIGS. 1 and 2). . The distillation column used in the distillation method of the multi-component mixture of the present invention is not limited to its type, but in order to minimize the thermal history of the product and to make the response to disturbance as fast as possible, A type having a small amount of raw material retained is preferable, and a typical example thereof is a packed column type distillation column.

【0012】また、原料の組成分析計は、組成の正確な
同定及び定量ができ、且つその分析時間が比較的速いも
のであれば制限されないが、特に、実開平2−1245
54号公報、実開平1−118360号公報及び実開平
5−23130号公報に記載されているようなオンライ
ン測定に有用なガスクロマトグラフ及び試料導入装置が
好ましい。
The composition analyzer of the raw material is not limited as long as the composition can be accurately identified and quantified and the analysis time is relatively fast.
A gas chromatograph and a sample introduction device useful for on-line measurement such as those described in Japanese Patent Publication No. 54, Japanese Utility Model Publication No. 1-118360 and Japanese Utility Model Publication No. 5-23130 are preferable.

【0013】また、原料等の測定に用いる流量計は、特
に制限されず、公知のものを用いることができる。上記
の原料の組成分析計及び流量計による測定値の測定誤差
は、本発明の実施に際して、蒸留塔に適切に設置された
温度計により検出される塔内の温度又は温度差が、それ
らの設定値に一致するように留出量をカスケード制御す
ることにより解消される。この際、蒸留塔が加圧又は減
圧下で運転される場合は、塔内の圧力が塔内の温度に大
きく影響するので、塔内の圧力の変動による影響をさけ
るために、温度差を制御パラメーターとするのが好まし
い。
The flow meter used for measuring the raw materials and the like is not particularly limited, and a known one can be used. The measurement error of the measured values by the composition analyzer and the flow meter of the above-mentioned raw materials is the temperature in the column or the temperature difference detected by the thermometer appropriately installed in the distillation column when the present invention is carried out, and the setting thereof is set. It is solved by controlling the amount of distillate so as to match the value. At this time, when the distillation column is operated under pressure or reduced pressure, the pressure inside the column greatly affects the temperature inside the column, so the temperature difference is controlled in order to avoid the influence of fluctuations in the pressure inside the column. It is preferably used as a parameter.

【0014】また、本発明の多成分系混合物の蒸留方法
においては、分離に必要な加熱エネルギーを最小にする
ため、原料の供給量を減少させた場合でも、過剰の還流
量の運転にならず、各々の蒸留塔内のたき上げ蒸気量
(留出量と還流量との合計量)と留出量との比が一定と
なるように、リボイラー加熱量を制御することが好まし
い。また、この制御の際、リボイラー加熱量の制御スキ
ームは、特に制限されず、内部還流制御法等の公知の制
御スキームを適宜選択することができる。
Further, in the method for distilling a multi-component mixture of the present invention, since the heating energy required for separation is minimized, even if the feed amount of the raw material is reduced, the operation at an excessive reflux amount does not occur. It is preferable to control the reboiler heating amount so that the ratio of the amount of lifted steam (total amount of distillate amount and reflux amount) and the distillate amount in each distillation column is constant. In this control, the control scheme of the reboiler heating amount is not particularly limited, and a known control scheme such as the internal reflux control method can be appropriately selected.

【0015】本発明の多成分系混合物の蒸留方法におい
て蒸留分離の対象とされる原料は、蒸気圧の異なる複数
成分から成る多成分系混合物であれば制限されないが、
本発明の蒸留方法は、特に、炭素数6〜20の脂肪酸、
炭素数6〜20の脂肪酸低級アルキルエステル又は炭素
数6〜20の高級アルコール等の多成分系混合物から所
定の組成物(ここで言う所定の組成物は、単一化合物又
は複数の化合物の混合物を意味する)を分離するのに適
している。上記の化合物は界面活性剤に誘導され用いら
れる際、炭素数による界面活性性能に応じて商品設計す
る上で純度の高い化合物が有用に用いられるため、上記
の多成分系混合物に対して本発明の多成分系混合物の蒸
留方法がより好ましく適用される。
In the method for distilling a multi-component mixture of the present invention, the raw material to be separated by distillation is not limited as long as it is a multi-component mixture consisting of a plurality of components having different vapor pressures.
The distillation method of the present invention is particularly applicable to fatty acids having 6 to 20 carbon atoms,
A predetermined composition from a multi-component mixture such as a C6 to C20 fatty acid lower alkyl ester or a C6 to C20 higher alcohol (a predetermined composition here means a single compound or a mixture of a plurality of compounds. (Meaning) is suitable for separating. When the above compound is used after being induced by a surfactant, a compound with high purity is usefully used for product design according to the surfactant performance depending on the number of carbon atoms. The method for distilling a multi-component mixture of is more preferably applied.

【0016】以下、本発明の多成分系混合物の蒸留方法
の実施に用いられる蒸留装置の例を図3を参照して、そ
の作用と共に説明する。図3は本発明の多成分系混合物
の蒸留方法の一実施態様に用いられる蒸留装置の要部の
例を詳細に示すフロー図である。
An example of a distillation apparatus used for carrying out the method for distilling a multi-component mixture according to the present invention will be described below with reference to FIG. 3 together with its operation. FIG. 3 is a flow chart showing in detail an example of a main part of a distillation apparatus used in one embodiment of the method for distilling a multi-component mixture of the present invention.

【0017】蒸留塔における分離能力は、供給される原
料の組成が一定であれば、物質収支、蒸留塔の理論段数
及び還流比のみによって定められる。即ち、蒸留塔にお
ける分離能力は、考えられる原料の組成の変動範囲内
で、ある所定の還流比を定めて所定の組成まで分離でき
る理論段数を決定すると、定めた還流比を維持するよう
に蒸留塔の運転を行うことにより、下記に示す如く、物
質収支のみによって制御される。
The separation capacity in the distillation column is determined only by the mass balance, the theoretical plate number of the distillation column, and the reflux ratio if the composition of the raw materials supplied is constant. In other words, the separation capacity in the distillation column is such that when a certain reflux ratio is set within the range of fluctuation of the composition of the raw material considered and the number of theoretical plates capable of separating up to the predetermined composition is determined, distillation is performed so as to maintain the specified reflux ratio. By operating the tower, it is controlled only by the mass balance, as shown below.

【0018】蒸留塔に対して原料の供給量をF、所定の
組成物(留出物)の留出量をD、缶出量をBとし、原料
中の特定成分の重量含有率をXF 、留出物中の特定成分
の重量含有率をXD (設定値)、缶出物中の特定成分の
重量含有率をXB (設定値)とすると、蒸留塔への入出
量の収支と特定成分についての物質収支より、 F=D+B ・・・(1) F×XF =D×XD +B×XB ・・・(2) となり、(1)式及び(2)式より、 D=F×{(XF −XB )/(XD −XB )}・・・(3) なる関係が得られる。XD 、XB は、分離しようとする
設定値であるため、原料中の特定成分の重量含有率XF
と供給量Fとがわかれば、留出物の留出量を定めること
ができる。
The feed amount of the raw material to the distillation column is F, the distillate amount of a predetermined composition (distillate) is D and the bottom product amount is B, and the weight content of a specific component in the raw material is X F. Assuming that the weight content of the specific component in the distillate is X D (set value) and the weight content of the specific component in the bottom product is X B (set value), the balance of the amount of input and output to and from the distillation column is calculated. From the material balance of the specific component, F = D + B (1) F × X F = D × X D + B × X B (2), and from the equations (1) and (2), D = F × {(X F −X B ) / (X D −X B )} (3). Since X D and X B are set values to be separated, the weight content X F of the specific component in the raw material is X F.
If the supply amount F is known, the distillate amount of the distillate can be determined.

【0019】本発明の多成分系混合物の蒸留方法におい
ては、上述のようにして定めた留出量で所定の組成物
(留出物)を得るために、蒸留装置は、例えば下記に述
べる制御系により、蒸留塔の両端組成が制御されるよう
になしてある。尚、図1において、1は連結された複数
の蒸留塔の中の任意の蒸留塔であり、被蒸留成分の供給
流量は前塔におけるボトム液面調節計40又は留出物流
量計23によりバルブ21で制御されている。
In the method for distilling a multi-component mixture according to the present invention, in order to obtain a predetermined composition (distillate) with a distillate amount determined as described above, the distillation apparatus is controlled, for example, as described below. The system controls the composition of both ends of the distillation column. In FIG. 1, 1 is an arbitrary distillation column among a plurality of connected distillation columns, and the supply flow rate of the components to be distilled is controlled by the bottom liquid level controller 40 or the distillate flow meter 23 in the previous column. It is controlled by 21.

【0020】本発明においては、所定の組成物(留出
物)の留出量は、以下に述べる如く制御されている。脱
ガス、乾燥工程等を経た原料は、最初の蒸留塔に供給さ
れる前に、原料流量計20によりある所定の流量(F)
になるよう制御され、周期的にプロセス分析計10によ
りその組成が測定される。上記プロセス分析計10によ
って、原料の組成を測定する周期は、特に限定されず対
象とする多成分系混合物により適宜設定すればよいが、
好ましくは3分〜10時間、更に好ましくは5分〜2時
間である。そして、上記の流量(F)及び組成の測定結
果が、物質収支演算器121へ出力される。
In the present invention, the amount of distillate of a given composition (distillate) is controlled as described below. The raw material that has undergone the degassing and drying steps, etc., is supplied to the first distillation column before being fed to a predetermined flow rate (F) by the raw material flow meter 20.
And the composition is measured by the process analyzer 10 periodically. The cycle for measuring the composition of the raw material by the process analyzer 10 is not particularly limited and may be appropriately set depending on the target multi-component mixture.
It is preferably 3 minutes to 10 hours, more preferably 5 minutes to 2 hours. Then, the measurement results of the flow rate (F) and the composition are output to the material balance calculator 121.

【0021】上記物質収支演算器121においては、原
料供給側より順次、各成分毎に測定結果XF 及び設定値
D 、XB を用いて上記(3)式に従って留出量Dが計
算され、それらの結果は加算器101へ出力される。
In the mass balance calculator 121, the distillate amount D is calculated according to the above equation (3) using the measurement results X F and the set values X D and X B for each component sequentially from the raw material supply side. , Their results are output to the adder 101.

【0022】一方、蒸留塔1内に設けられた温度検出器
31、32より減算器103を用いて求めた温度差を実
測値とし、また予め設定された温度差を目標値として、
それぞれPID制御器113に出力し、そして、PID
制御器113では、上記目標値よりも上記実測値が小さ
い場合にプラスの信号が、また大きい場合にマイナスの
信号が付加されて、その信号が上記加算器101へ出力
される。
On the other hand, the temperature difference obtained by using the subtractor 103 from the temperature detectors 31 and 32 provided in the distillation column 1 is used as the measured value, and the preset temperature difference is used as the target value.
Output to PID controller 113 respectively, and PID
The controller 113 adds a positive signal when the measured value is smaller than the target value and a negative signal when the measured value is larger than the target value, and outputs the signal to the adder 101.

【0023】上記加算器101は、上記物質収支演算器
121によって計算された所定の組成物(留出物)の留
出量と上記PID制御器113によって付加された信号
の出力値との和を、目標値として留出物流量計23へ出
力する。そして、この留出物流量計23によって、所定
の組成物(留出物)の留出量が制御される。尚、予め設
定された温度差は、必要に応じて、圧力補正器130に
より下記の(4)式に従って補正された後、目標値とし
て上記PID制御器113に出力される。 ti =B/(A− logPi )−C,Pi =P+ΔP×n・・・(4) ここで、A、B及びCは定数、Pi は温度検出器Ti
の圧力であり、Pi は塔頂圧力計131の出力P,塔の
理論段圧力損失ΔP及び塔頂からTi までの理論段数n
より求める。
The adder 101 calculates the sum of the amount of the predetermined composition (distillate) calculated by the mass balance calculator 121 and the output value of the signal added by the PID controller 113. , To the distillate flowmeter 23 as a target value. The distillate flow meter 23 controls the distillate amount of a predetermined composition (distillate). The preset temperature difference is corrected by the pressure corrector 130 according to the following equation (4), if necessary, and then output as a target value to the PID controller 113. t i = B / (A−logP i ) −C, P i = P + ΔP × n (4) where A, B and C are constants, and P i is the pressure at the temperature detector T i . , P i is the output P of the top pressure gauge 131, the theoretical stage pressure loss ΔP of the column, and the number n of theoretical stages from the top of the column to T i.
Ask more.

【0024】また、リボイラー加熱量は、以下に述べる
如く制御することが好ましい。リボイラー2では、塔内
でのたき上げ蒸気量が一定となるように、その加熱量が
制御される。加熱量演算器(A)122では、予め設定
した原料供給量F0 の時の必要加熱量QT 及び塔からの
放熱量QL より、原料供給量Fの時の必要熱量Qが下記
の(5)式に従って計算され、加算器102へ出力され
る。 Q=QT ×F/FO +QL ・・・(5)
The reboiler heating amount is preferably controlled as described below. In the reboiler 2, the heating amount is controlled so that the amount of lifted steam in the tower is constant. In the heating amount computing unit (A) 122, from the heat radiation amount Q L from necessary heating amount Q T and the tower when the raw material supply amount F 0 which is set in advance, must quantity Q when the material supply amount F is the following ( It is calculated according to the equation (5) and output to the adder 102. Q = Q T × F / F O + Q L (5)

【0025】一方、加熱量演算器(B)123では、留
出量(D)を上記留出物流量計23により、また還流量
(R)を還流液流量計22によりそれぞれ検出し、たき
上げ蒸気量(L=D+R)を計算し、このたき上げ蒸気
量(L)がPID制御器112へ出力される。上記PI
D制御器112では、計算した上記たき上げ蒸気量
(L)を実測値とし、また、予め設定された原料供給量
O の時に必要なたき上げ蒸気量(LO )を用いLC
0 ×F/FO を目標値として、差分(LC −L)を計
算し上記加算器102へ出力される。
On the other hand, in the heating amount calculator (B) 123, the distillate amount (D) is detected by the distillate flow meter 23 and the reflux amount (R) is detected by the reflux liquid flow meter 22, respectively, and lifted. The amount of steam (L = D + R) is calculated, and this amount of lifted steam (L) is output to the PID controller 112. PI above
In the D controller 112, the calculated amount of lifted steam (L) is used as an actual measurement value, and the amount of lifted steam (L O ) required at a preset raw material supply amount F O is used as L C =
The difference (L C −L) is calculated with L 0 × F / F O as the target value and is output to the adder 102.

【0026】上記加算器102では、(5)式で計算さ
れたQ及び上記たき上げ蒸気量の差分(LC −L)を熱
量QC に換算した上、加算した結果がPID制御器11
1へ出力される。
[0026] In the adder 102, (5) on the calculated Q and the Taki raise steam amount of the difference of (L C -L) was converted to the amount of heat Q C by the formula, the result obtained by adding the PID controller 11
It is output to 1.

【0027】一方、加熱量演算器(C)124では、加
熱源の流量(WH )を検出し、気相加熱であれば下記の
(6)式より加熱量Qを計算し、また、液相加熱であれ
ばリボイラー2の熱媒体の出入口温度差ΔTH を検出し
て下記の(7)式より加熱量Qを計算し、この加熱量Q
が、上記PID制御器111へ実測値として出力され
る。 Q=λH ×WH ・・・(6) Q=CpH ×WH ×ΔTH ・・・(7)
On the other hand, the heating amount calculator (C) 124 detects the flow rate ( WH ) of the heating source, and in case of gas phase heating, calculates the heating amount Q from the following equation (6), In the case of phase heating, the inlet / outlet temperature difference ΔT H of the heat medium of the reboiler 2 is detected, the heating amount Q is calculated from the following equation (7), and this heating amount Q
Is output to the PID controller 111 as a measured value. Q = λ H × W H (6) Q = Cp H × W H × ΔT H (7)

【0028】そして、上記PID制御器111では、上
記加算器102からの出力を目標値として、加熱源流量
計24を制御し、この加熱源流量計24の制御によっ
て、上記加熱源の流量(WH )が制御されて、リボイラ
ー加熱量が制御される。
The PID controller 111 controls the heating source flow meter 24 with the output from the adder 102 as a target value, and the heating source flow meter 24 controls the flow rate (W) of the heating source. H ) is controlled to control the reboiler heating amount.

【0029】本発明の多成分系混合物の蒸留方法によれ
ば、所定の組成物(留出物)の留出量は、前述の如く、
最初の蒸留塔に供給される原料の供給流量及びその組成
を周期的に検出し、この検出結果に基づいて物質収支を
演算することにより設定されるため、上流側の蒸留塔で
原料の供給量の変動やその組成の変動等の外乱が発生し
ても、所定の組成物(留出物)の純度が一定に維持され
る。
According to the method for distilling a multi-component mixture of the present invention, the distillate amount of a given composition (distillate) is as described above.
It is set by periodically detecting the supply flow rate and composition of the raw material supplied to the first distillation column and calculating the material balance based on this detection result. Even if a disturbance such as a change in the composition or a change in the composition occurs, the purity of a predetermined composition (distillate) is maintained constant.

【0030】[0030]

【実施例】以下、本発明の多成分系混合物の蒸留方法の
一実施態様について、図1を参照して、更に具体的に説
明するが、本発明はこれらに限定されるものではない。
尚、本実施例において用いた多成分系混合物(高級アル
コール)及びその成分の重量含有率を〔表1〕に示し
た。本発明の蒸留方法に用いた装置は、蒸留塔として、
住友メラパック(規則充填物)を充填した充填塔型蒸留
塔を用い、この蒸留塔を5基直列に連結した図1及び図
3に示した装置構成とした。尚、以下においては、これ
ら5基の蒸留塔を高級アルコールの供給側より順に、第
1塔、第2塔・・・と言う。
EXAMPLES One embodiment of the method for distilling a multi-component mixture according to the present invention will be described below more specifically with reference to FIG. 1, but the present invention is not limited thereto.
The weight content of the multi-component mixture (higher alcohol) and its components used in this example is shown in [Table 1]. The apparatus used in the distillation method of the present invention, as a distillation column,
A packed column type distillation column filled with Sumitomo Melapak (ordered packing) was used, and the device configuration shown in FIGS. 1 and 3 was formed by connecting five distillation columns in series. In the following, these five distillation columns will be referred to as a first column, a second column, ... In order from the higher alcohol supply side.

【0031】上記の装置を用い、〔表1〕に示した高級
アルコールを本発明の蒸留方法に従って蒸留分離し、各
蒸留塔における留出物の組成(平均純度)の測定を行っ
た。その結果を制御目標値(設定値)と共に〔表2〕に
示す。尚、高級アルコールの組成及び各留出物の組成の
分析は、全てガスクロマトグラフを用いて行った。ま
た、各蒸留塔では下記〔表2〕に示す成分を主成分とす
る留出物を分離した。
Using the above apparatus, the higher alcohols shown in [Table 1] were separated by distillation according to the distillation method of the present invention, and the composition (average purity) of the distillate in each distillation column was measured. The results are shown in [Table 2] together with the control target value (setting value). The analysis of the composition of higher alcohols and the composition of each distillate was carried out using a gas chromatograph. In addition, distillates containing the components shown in the following [Table 2] as main components were separated in each distillation column.

【0032】[0032]

【表1】 [Table 1]

【0033】また、本発明の蒸留方法に用いられる制御
系の両端組成制御に対する制御の堅固性について調べる
ために、高級アルコールの供給流量及びその組成を下記
のように変動させて蒸留分離を行い、各留出物の組成の
測定を行った結果、〔表2〕と同様の組成が得られた。
高級アルコールの供給流量は、その設定値を急激に+
3、−3%増減することにより変動させた。この際、高
級アルコールの供給流量及びその組成を10分毎に周期
的に検出した。高級アルコールの組成は、高級アルコー
ル100重両部に対して炭素数12のアルコール5重量
部を速やかに混合することにより変動させた。この際、
高級アルコールの供給量及びその組成を10分毎に周期
的に検出した。
Further, in order to investigate the robustness of the control of the control system used in the distillation method of the present invention with respect to the control of the composition at both ends, distillation separation is carried out by varying the supply flow rate of higher alcohol and its composition as follows. As a result of measuring the composition of each distillate, the same composition as in [Table 2] was obtained.
The supply flow rate of high-grade alcohol rapidly increases the set value +
It was varied by increasing or decreasing by 3 to -3%. At this time, the supply flow rate of higher alcohol and its composition were periodically detected every 10 minutes. The composition of the higher alcohol was varied by rapidly mixing 5 parts by weight of an alcohol having 12 carbon atoms with 100 parts by weight of the higher alcohol. On this occasion,
The supply amount of higher alcohol and its composition were periodically detected every 10 minutes.

【0034】[0034]

【表2】 [Table 2]

【0035】〔表2〕の結果から明らかなように、各塔
において分離された成分の重量含有率の平均純度は、設
定値とほぼ一致した。また、制御の堅固性については、
設定値に対する実測値の変動の幅(振幅)が最大でも第
3塔の0.3%であり、両端組成制御に対して制御の堅
固性に優れていた。
As is clear from the results of [Table 2], the average purity of the weight content of the components separated in each column was substantially equal to the set value. Also, regarding the robustness of control,
The fluctuation width (amplitude) of the measured value with respect to the set value was 0.3% of the third tower even at the maximum, and the robustness of the control was excellent with respect to the composition control at both ends.

【0036】尚、本発明は上記実施例に制限されず、本
発明の趣旨を逸脱しない範囲で各測定に用いられる測定
器を適宜変更可能である。
The present invention is not limited to the above embodiments, and the measuring instruments used for each measurement can be changed as appropriate without departing from the spirit of the present invention.

【0037】[0037]

【発明の効果】本発明の多成分系混合物の蒸留方法は、
原料の供給流量の変動やその組成の変動等の外乱に拘わ
らず、制御の堅固性に優れ且つ汎用性に優れている。
The distillation method of the multi-component mixture of the present invention is
It has excellent control robustness and versatility regardless of disturbances such as fluctuations in the supply flow rate of raw materials and fluctuations in its composition.

【図面の簡単な説明】[Brief description of drawings]

【図1】図1は、本発明の多成分系混合物の蒸留方法の
実施に用いられる装置例の構成図である。
FIG. 1 is a configuration diagram of an example of an apparatus used for carrying out a method for distilling a multi-component mixture according to the present invention.

【図2】図2は、本発明の多成分系混合物の蒸留方法の
実施に用いられる装置の他の例の構成図である。
FIG. 2 is a schematic diagram of another example of an apparatus used for carrying out the method for distilling a multi-component mixture of the present invention.

【図3】図3は本発明の多成分系混合物の蒸留方法の一
実施態様に用いられる蒸留装置の要部の例を詳細に示す
フロー図である。
FIG. 3 is a flow chart showing in detail an example of a main part of a distillation apparatus used in one embodiment of a method for distilling a multi-component mixture of the present invention.

【符号の説明】[Explanation of symbols]

1 蒸留塔 2 リボイラー 3 全縮器 4 留分受器 10 プロセス分析計 20 原料流量計 21 バルブ 22 還流液流量計 23 留出物流量計 24 加熱源流量計 31 温度検出器 32 温度検出器 101 加算器 102 加算器 103 減算器 111 PID制御器 112 PID制御器 113 PID制御器 121 物質収支演算器 122 加熱量演算器(A) 123 加熱量演算器(B) 124 加熱量演算器(C) 1 Distillation Tower 2 Reboiler 3 Full Compressor 4 Distillation Receiver 10 Process Analyzer 20 Raw Material Flowmeter 21 Valve 22 Reflux Liquid Flowmeter 23 Distillate Flowmeter 24 Heating Source Flowmeter 31 Temperature Detector 32 Temperature Detector 101 Addition Device 102 Adder 103 Subtractor 111 PID controller 112 PID controller 113 PID controller 121 Material balance calculator 122 Heating amount calculator (A) 123 Heating amount calculator (B) 124 Heating amount calculator (C)

───────────────────────────────────────────────────── フロントページの続き (72)発明者 遠藤 泰永 東京都田無市谷戸町2丁目1番1号住友重 機械工業株式会社プラントエンジニアリン グ事業部内 (72)発明者 井出 進 東京都田無市谷戸町2丁目1番1号住友重 機械工業株式会社プラントエンジニアリン グ事業部内 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yasunaga Endo 2-1-1 Yadocho, Tanashi-shi, Tokyo Metropolitan Plant Engineering Department, Sumitomo Heavy Industries, Ltd. (72) Susumu Ide Yatocho, Tanashi-shi, Tokyo 2-1, 1-1 Sumitomo Heavy Industries, Ltd. Plant Engineering Department

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】 複数の蒸留塔を用い、多成分系混合物か
ら所定の組成物を連続的に分離する方法であって、 (1)少なくとも3基以上の蒸留塔を直列に又は直列と
並列とに連結した装置構成であって、 (2)最初の蒸留塔に供給される原料の供給流量及びそ
の組成を周期的に検出し、この検出結果に基づいて、物
質収支を演算することにより、各々の蒸留塔から留出す
る上記組成物の留出量を同時に設定し、 (3)検出した塔内の温度又は温度差と、予め設定した
塔内の温度又は温度差との偏差を、上記物質収支より設
定した上記留出量に対してカスケード制御することを特
徴とする多成分系混合物の蒸留方法。
1. A method for continuously separating a predetermined composition from a multi-component mixture by using a plurality of distillation columns, which comprises (1) at least three distillation columns in series or in series and in parallel. (2) The feed flow rate of the raw material supplied to the first distillation column and its composition are periodically detected, and the material balance is calculated based on the detection result. The distillation amount of the above-mentioned composition distilled from the distillation column of (1) is set at the same time, and (3) the deviation between the detected temperature or temperature difference in the column and the preset temperature or temperature difference in the column is calculated as the above substance. A method for distilling a multi-component mixture, which comprises performing cascade control on the above-mentioned amount of distillate set from the balance.
【請求項2】 上記多成分系混合物が、炭素数6〜20
の脂肪酸、炭素数6〜20の脂肪酸低級アルキルエステ
ル又は炭素数6〜20の高級アルコールであることを特
徴とする請求項1記載の多成分系混合物の蒸留方法。
2. The multi-component mixture has 6 to 20 carbon atoms.
2. The method for distilling a multi-component mixture according to claim 1, wherein the fatty acid is a C6 to C20 fatty acid lower alkyl ester or a C6 to C20 higher alcohol.
JP32717793A 1993-12-24 1993-12-24 Method for distilling multicomponent mixture Pending JPH07178301A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP32717793A JPH07178301A (en) 1993-12-24 1993-12-24 Method for distilling multicomponent mixture

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP32717793A JPH07178301A (en) 1993-12-24 1993-12-24 Method for distilling multicomponent mixture

Publications (1)

Publication Number Publication Date
JPH07178301A true JPH07178301A (en) 1995-07-18

Family

ID=18196174

Family Applications (1)

Application Number Title Priority Date Filing Date
JP32717793A Pending JPH07178301A (en) 1993-12-24 1993-12-24 Method for distilling multicomponent mixture

Country Status (1)

Country Link
JP (1) JPH07178301A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005336066A (en) * 2004-05-25 2005-12-08 Mitsubishi Chemicals Corp Method for producing (meth)acrolein or (meth)acrylic acid

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005336066A (en) * 2004-05-25 2005-12-08 Mitsubishi Chemicals Corp Method for producing (meth)acrolein or (meth)acrylic acid

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