JPH0655733B2 - Recovery method of ethylene oxide - Google Patents

Recovery method of ethylene oxide

Info

Publication number
JPH0655733B2
JPH0655733B2 JP60152436A JP15243685A JPH0655733B2 JP H0655733 B2 JPH0655733 B2 JP H0655733B2 JP 60152436 A JP60152436 A JP 60152436A JP 15243685 A JP15243685 A JP 15243685A JP H0655733 B2 JPH0655733 B2 JP H0655733B2
Authority
JP
Japan
Prior art keywords
ethylene oxide
tower
liquid
absorption
ethylene
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
JP60152436A
Other languages
Japanese (ja)
Other versions
JPS6216472A (en
Inventor
行彦 柿本
宣明 梶本
勇 木口
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.)
Nippon Shokubai Co Ltd
Original Assignee
Nippon Shokubai Co Ltd
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 Nippon Shokubai Co Ltd filed Critical Nippon Shokubai Co Ltd
Priority to JP60152436A priority Critical patent/JPH0655733B2/en
Publication of JPS6216472A publication Critical patent/JPS6216472A/en
Publication of JPH0655733B2 publication Critical patent/JPH0655733B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/10—Process efficiency
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals

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  • Epoxy Compounds (AREA)

Description

【発明の詳細な説明】 （産業上の利用分野） 本発明は、エチレンを銀触媒の存在下、分子状酸素含有
ガスにより接触気相酸化して得られるエチレンオキシド
を回収する方法に関するものである。さらに詳しくは、
エチレンを銀触媒の存在下、分子状酸素含有ガスにより
接触気相酸化して得られるエチレンオキシドを含む反応
生成ガスをエチレンオキシド吸収塔へ導き吸収液に吸収
させてエチレンオキシドを回収し、ついでエチレンオキ
シドを含む吸収液をエチレンオキシド放散塔へ送り加熱
によりエチレンオキシド放散塔頂よりエチレンオキシド
を放散しエチレンオキシド放散塔底部より抜き出した液
の一部はエチレンオキシド吸収塔へ導き吸収液として循
環使用する工程において、エチレンオキシド放散塔底部
からヒートポンプを用いて熱回収を行い熱回収により発
生した低圧蒸気を他の加熱源、例えばエチレンオキシド
精留塔の熱源として利用するエチレンオキシドの回収方
法に関するものである。TECHNICAL FIELD The present invention relates to a method for recovering ethylene oxide obtained by catalytic vapor-phase oxidation of ethylene with a molecular oxygen-containing gas in the presence of a silver catalyst. For more details,
A reaction product gas containing ethylene oxide, which is obtained by catalytic vapor-phase oxidation of ethylene with a molecular oxygen-containing gas in the presence of a silver catalyst, is introduced into an ethylene oxide absorption tower to be absorbed in an absorbing liquid to recover ethylene oxide, and then an absorption containing ethylene oxide. When the liquid is sent to the ethylene oxide diffusion tower, ethylene oxide is diffused from the top of the ethylene oxide diffusion tower by heating, and part of the liquid extracted from the bottom of the ethylene oxide diffusion tower is introduced to the ethylene oxide absorption tower and recycled as an absorption liquid. The present invention relates to a method for recovering ethylene oxide in which the low-pressure steam generated by the heat recovery is used as another heat source, for example, as a heat source for an ethylene oxide rectification column.

（従来の技術） エチレンオキシドを回収する工程において、反応生成ガ
スを水を主とする吸収液に吸収させエチレンオキシド水
溶液として回収し、この水溶液からエチレンオキシドを
放散せしめてエチレンオキシドを得ている。エチレンオ
キシドは一般につぎのようにして回収される。エチレン
と分子状酸素含有ガスとを銀触媒上で接触気相酸化して
生成するエチレンオキシドを含む反応生成ガスをエチレ
ンオキシド吸収塔へ導びき水を主とする吸収液と向流接
触させエチレンオキシド水溶液として回収し、ついでエ
チレンオキシド放散塔へ送りエチレンオキシド放散塔底
部を加熱用蒸気で加熱することによってエチレンオキシ
ドを水溶液から放散させ、エチレンオキシド放散塔底部
より抜き出された実質的にエチレンオキシドを含まない
水溶液は吸収液として循環使用し、エチレンオキシド放
散塔頂部より放散されるエチレンオキシド、水、二酸化
炭素、不活性ガス（窒素、アルゴン、メタン、エタ
ン、）の他ホルムアルデヒド等の低沸点不純物およびア
セトアルデヒド、酢酸等の高沸点不純物を含む放散物を
脱水工程、軽質分分離工程および重質分分離工程の各々
を経て精製しエチレンオキシドを製造することができ
る。(Prior Art) In the step of recovering ethylene oxide, a reaction product gas is absorbed by an absorption liquid mainly containing water and recovered as an ethylene oxide aqueous solution, and ethylene oxide is diffused from this aqueous solution to obtain ethylene oxide. Ethylene oxide is generally recovered as follows. A reaction product gas containing ethylene oxide produced by catalytic gas-phase oxidation of ethylene and a gas containing molecular oxygen on a silver catalyst is introduced to an ethylene oxide absorption tower and countercurrently contacted with an absorption liquid mainly composed of water to recover as an ethylene oxide aqueous solution. Then, it is sent to an ethylene oxide stripping tower to release ethylene oxide from the aqueous solution by heating the bottom of the ethylene oxide stripping tower with heating steam, and the aqueous solution containing substantially no ethylene oxide extracted from the bottom of the ethylene oxide stripping tower is circulated as an absorption liquid. Used and contains ethylene oxide, water, carbon dioxide, inert gas (nitrogen, argon, methane, ethane, etc.) and low boiling point impurities such as formaldehyde and high boiling point impurities such as acetaldehyde and acetic acid that are emitted from the top of the ethylene oxide stripping tower. Light dewatering process Purification over each minute separation step and heavies separation step can be produced ethylene oxide.

（発明が解決しようとする問題点） しかしながら、このようなエチレンオキシドの回収方法
は、エチレンオキシド放散塔底部より抜き出された液が
有する熱エネルギーを回収する点については十分でな
く、大量の熱量が系外に廃棄されるという問題があっ
た。従来の方法は１００〜１３０℃のエチレンオキシド
放散塔底液をエチレンオキシド吸収塔底液と熱交換さ
せ、熱量の回収をなった後冷却してエチレンオキシド吸
収塔の吸収液としていた。本発明はこれらのエチレンオ
キシド回収工程における省エネルギーについて研究した
結果エチレンオキシド放散塔底液の有するエネルギーの
有効利用に着眼し本発明を完成した。(Problems to be Solved by the Invention) However, such a method for recovering ethylene oxide is not sufficient for recovering the thermal energy of the liquid withdrawn from the bottom of the ethylene oxide diffusion column, and a large amount of heat is generated in the system. There was a problem of being discarded outside. In the conventional method, the bottom liquid of the ethylene oxide stripping tower at 100 to 130 ° C. was heat-exchanged with the bottom liquid of the ethylene oxide absorption tower, and after the heat quantity was recovered, it was cooled to obtain the absorption liquid of the ethylene oxide absorption tower. As a result of research on energy saving in these ethylene oxide recovery steps, the present invention was completed with the aim of effectively utilizing the energy of the bottom liquid of the ethylene oxide stripping column.

（問題点を解決するための手段） エチレンを銀触媒の存在下、分子状酸素含有ガスと接触
気相酸化して生成したエチレンオキシドを含有する反応
生成ガスをエチレンオキシド吸収塔へ導入し吸収液と向
流接触させ、エチレンオキシド吸収塔頂部よりのガスは
炭酸ガス吸収工程および／またはエチレン酸化反応工程
へ循環し、エチレンオキシドを含むエチレンオキシド吸
収塔底液はエチレンオキシド放散塔へ供給し、エチレン
オキシド放散塔頂部からエチレンオキシドを放散せし
め、エチレンオキシド放散塔底部より抜き出した液はエ
チレンオキシド吸収塔へ導き吸収液として循環使用し、
放散塔底部より抜き出した液の一部はその液に含まれる
エチレングリコールを濃縮するため副生エチレングリコ
ール濃縮塔へ送る工程において、エチレンオキシド放散
塔底部より抜き出した液を熱交換器にてエチレンオキシ
ド吸収塔底液と熱交換した後、ヒートポンプを用いて吸
収液の持つ熱エネルギーを回収し、水蒸気を発生させ、
ヒートポンプにより冷却された吸収液をさらに冷却器に
て冷却した後、エチレンオキシド吸収塔の吸収液とする
ことを特徴とするエチレンオキシドの回収方法に関する
ものである。(Means for Solving Problems) A reaction product gas containing ethylene oxide produced by catalytic vapor-phase oxidation of ethylene with a molecular oxygen-containing gas in the presence of a silver catalyst is introduced into an ethylene oxide absorption tower to be mixed with an absorption liquid. Flow-contact, the gas from the top of the ethylene oxide absorption tower is circulated to the carbon dioxide absorption step and / or the ethylene oxidation reaction step, the ethylene oxide absorption bottom liquid containing ethylene oxide is supplied to the ethylene oxide stripping tower, and ethylene oxide is fed from the top of the ethylene oxide stripping tower. The liquid that was diffused and withdrawn from the bottom of the ethylene oxide diffusion column was introduced to the ethylene oxide absorption column and circulated and used as an absorption liquid.
Part of the liquid extracted from the bottom of the stripping tower is sent to the ethylene glycol concentrating tower, which is a by-product for concentrating the ethylene glycol contained in the liquid, in the process of feeding the liquid extracted from the bottom of the ethylene oxide stripping tower with an ethylene oxide absorption tower. After exchanging heat with the bottom liquid, the heat energy of the absorbing liquid is recovered using a heat pump to generate steam,
The present invention relates to a method for recovering ethylene oxide, characterized in that the absorption liquid cooled by a heat pump is further cooled by a cooler and then used as the absorption liquid in an ethylene oxide absorption tower.

本発明においてエチレンオキシド吸収塔へ供給される吸
収液の温度は５〜４０℃、好ましくは１〜３５℃であ
り、吸収液の組成はpHが５〜１２、好ましくは６〜１
１、エチレングリコール濃度が１〜４０重量％、好まし
くは５〜３０重量％、消泡剤濃度が０．１ppm以上、好
ましくは１〜１００ppm、残り水の範囲に制御される。
吸収液中のエチレングリコール濃度を一定に保持するた
めに、エチレンオキシド吸収塔とエチレンオキシド放散
塔とを循環する吸収液の一部をエチレンオキシド放散塔
底部から抜き出し副生エチレングリコール濃縮塔へ送
り、必要により新鮮な水を導入して制御される。pHの調
節は、たとえばカリウム、ナトリウムのようなアルカリ
金属の水酸化物や炭酸塩等の吸収液に溶解する化合物を
添加することにより行うのが好ましく、添加剤は具体的
には水酸化カリウムまたは水酸化ナトリウムが好まし
い。In the present invention, the temperature of the absorption liquid supplied to the ethylene oxide absorption tower is 5 to 40 ° C., preferably 1 to 35 ° C., and the composition of the absorption liquid has a pH of 5 to 12, preferably 6 to 1
1, the ethylene glycol concentration is 1 to 40% by weight, preferably 5 to 30% by weight, the antifoaming agent concentration is 0.1 ppm or more, preferably 1 to 100 ppm, and the remaining water is controlled within the range.
In order to keep the ethylene glycol concentration in the absorption liquid constant, a part of the absorption liquid that circulates in the ethylene oxide absorption tower and the ethylene oxide diffusion tower is withdrawn from the bottom of the ethylene oxide diffusion tower and sent to the by-product ethylene glycol concentration tower, and if necessary fresh It is controlled by introducing fresh water. The pH is preferably adjusted by adding a compound that is soluble in an absorbing solution such as a hydroxide or carbonate of an alkali metal such as potassium or sodium, and the additive is specifically potassium hydroxide or Sodium hydroxide is preferred.

消泡剤は、エチレンオキシド、副生エチレングリコール
等に不活性であり、吸収液の消泡効果を有するものであ
ればいかなる消泡剤でも使用でき、代表的な例としては
水溶性シリコンエマルジョンが吸収液への分散性、希釈
安定性、熱安定性が優れているので効果的である。The defoaming agent is inert to ethylene oxide, by-product ethylene glycol, etc., and any defoaming agent can be used as long as it has the defoaming effect of the absorbing liquid. As a typical example, water-soluble silicone emulsion is absorbed. It is effective because it has excellent dispersibility in a liquid, dilution stability, and thermal stability.

エチレンオキシド吸収塔の操作条件は、反応生成ガス中
のエチレンオキシド濃度が０．５〜５容量％、好ましく
は１．０〜４容量％であり、エチレンオキシド吸収塔の
操作圧は２〜４０kg／cm2Ｇ、好ましくは１０〜３０kg
／cm2Ｇである。エチレンオキシド放散塔の操作条件
は、エチレンオキシド放散塔頂圧力０．１〜１kg／cm2
Ｇ、好ましくは０．３〜０．６kg／cm2Ｇ、エチレンオ
キシド放散塔頂温度８５〜１１０℃、エチレンオキシド
放散塔底温度１１０〜１３０℃、エチレンオキシド放散
塔底エチレンオキシド濃度は１０ppm以下、好ましくは
０．５ppm以下である。The operating conditions of the ethylene oxide absorption tower are such that the ethylene oxide concentration in the reaction product gas is 0.5 to 5% by volume, preferably 1.0 to 4% by volume, and the operating pressure of the ethylene oxide absorption tower is 2 to 40 kg / cm 2 G. , Preferably 10-30kg
/ Cm 2 G. The operating conditions of the ethylene oxide stripping tower are such that the ethylene oxide stripping tower top pressure is 0.1 to 1 kg / cm 2.
G, preferably 0.3 to 0.6 kg / cm 2 G, ethylene oxide diffusion column top temperature 85 to 110 ° C., ethylene oxide diffusion column bottom temperature 110 to 130 ° C., ethylene oxide diffusion column bottom ethylene oxide concentration of 10 ppm or less, preferably 0.1. It is 5 ppm or less.

本発明のヒートポンプは、エチレンを銀触媒の存在下、
分子状酸素含有ガスと接触気相酸化して生成したエチレ
ンオキシドを含有する反応生成ガスをエチレンオキシド
吸収塔へ導入し吸収液と向流接触させ、エチレンオキシ
ド吸収塔頂部よりのガス一部はエチレン酸化反応工程へ
循環し、エチレンオキシドを含むエチレンオキシド吸収
塔底液はエチレンオキシド放散塔へ供給し、エチレンオ
キシド放散塔頂部からエチレンオキシドを放散せしめ、
エチレンオキシド放散塔底部より抜き出した液は熱交換
器にてエチレンオキシド吸収塔底液と熱交換した後、冷
却器にて冷却した後、エチレンオキシド吸収塔へ導き吸
収液として循環使用し、残部はその液に含まれるエチレ
ングリコールを濃縮するため副生エチレングリコール濃
縮塔へ送る工程において、エチレンオキシド放散塔底部
より抜き出した液は熱交換器にてエチレンオキシド吸収
塔底液と熱交換した後、冷却器に導く間に設置される。The heat pump of the present invention, ethylene in the presence of a silver catalyst,
A reaction product gas containing ethylene oxide produced by catalytic gas phase oxidation with a molecular oxygen-containing gas is introduced into an ethylene oxide absorption tower and brought into countercurrent contact with the absorbing liquid, and a part of the gas from the top of the ethylene oxide absorption tower is subjected to an ethylene oxidation reaction step. The ethylene oxide absorption tower bottom liquid containing ethylene oxide is supplied to the ethylene oxide diffusion tower, and ethylene oxide is diffused from the top of the ethylene oxide diffusion tower.
The liquid extracted from the bottom of the ethylene oxide stripping tower is heat-exchanged with the bottom liquid of the ethylene oxide absorption tower by a heat exchanger, cooled by a cooler, then introduced to the ethylene oxide absorption tower and circulated and used as an absorption liquid, and the rest is the liquid. In the process of sending the contained ethylene glycol to the by-product ethylene glycol concentrating tower to concentrate it, the liquid withdrawn from the bottom of the ethylene oxide stripping tower undergoes heat exchange with the ethylene oxide absorption tower bottom liquid in a heat exchanger, and then while being introduced into the cooler. Is installed.

本発明に用いるヒートポンプの作動流体としての冷媒
は、ヒートポンプのプロセスで蒸発疑縮を繰り返して循
環使用されるためその選択に当っては熱力学的性質のほ
かに熱的及び化学的に安定であること及び取り扱い上か
らは臭気、毒性、および爆発性を有しないことが要求さ
れる。本発明で使用できる冷媒としてはＲ−１１、Ｒ−
１２、Ｒ−２２、Ｒ−１１３及びＲ−１１４等のフッ化
炭化水素及びプロパン、ペンタン等の炭化水素類等が挙
げられるが、ヒートポンプ作動温度条件を考慮するとＲ
−１２、Ｒ−１１４がもっとも適している。The refrigerant as the working fluid of the heat pump used in the present invention is thermally and chemically stable in addition to the thermodynamic property in its selection because it is repeatedly circulated and repeatedly used in the process of the heat pump. In terms of handling and handling, it is required to have no odor, toxicity and explosiveness. As the refrigerant usable in the present invention, R-11 and R-
12, R-22, R-113, and R-114, and other fluorocarbons, and propane, pentane, and other hydrocarbons.
-12 and R-114 are the most suitable.

本発明のヒートポンプの操作条件としてはエチレンオキ
シド放散塔底部から出てエチレンオキシド吸収塔底液と
熱交換器により熱回収されたエチレンオキシドを実質的
に含まないエチレンオキシド放散塔底液が５０〜６０℃
の温度で冷媒の蒸発器へ入り冷媒を蒸発させ、その結果
エチレンオキシド放散塔底液の温度が５〜２０℃低下
し、冷媒蒸発器を出た後冷却されエチレンオキシド吸収
液としてエチレンオキシド吸収塔に導入される。The operating conditions of the heat pump of the present invention are 50 to 60 ° C. for the ethylene oxide stripping bottom liquid which is substantially free of ethylene oxide which is discharged from the bottom of the ethylene oxide stripping tower and recovered by the heat exchanger.
The temperature of the bottom liquid of the ethylene oxide stripping tower decreases by 5 to 20 ° C. as a result of evaporating the refrigerant into the evaporator of the refrigerant at the temperature of 5 ° C., and after exiting the refrigerant evaporator, it is cooled and introduced into the ethylene oxide absorption tower as the ethylene oxide absorbing liquid. It

エチレンオキシド放散塔底液により冷媒蒸発器で蒸発し
た冷媒は遠心式又はスクリュウ式又は往復動式圧縮機に
より冷媒の飽和温度が８０〜１００℃を有する圧力に迄
圧縮される。昇圧された冷媒は下記の２つの方法により
熱を外部に与え凝縮してポンプにより冷媒蒸発器に送ら
れ循環使用される。The refrigerant evaporated in the refrigerant evaporator by the bottom liquid of the ethylene oxide diffusion column is compressed by the centrifugal, screw or reciprocating compressor to a pressure at which the saturation temperature of the refrigerant is 80 to 100 ° C. The pressure-increased refrigerant gives heat to the outside by the following two methods, is condensed, is sent to the refrigerant evaporator by a pump, and is circulated for use.

(1)他の精留塔例えばエチレンオキシド精留塔（塔底温
度５０〜７０℃）のリイボラーへ冷媒の蒸気を直接送り
凝縮させその凝縮熱を精留塔底液へ与える。(1) The vapor of the refrigerant is directly sent to the reboiler of another rectification column, for example, an ethylene oxide rectification column (column bottom temperature 50 to 70 ° C.) to be condensed, and the condensation heat is given to the rectification column bottom liquid.

(2)冷媒凝縮器へ冷媒蒸気を送り、冷媒凝縮器内の流
体、たとえば水に凝縮潜熱を与え冷媒は凝縮する。(2) The refrigerant vapor is sent to the refrigerant condenser, the latent heat of condensation is given to the fluid in the refrigerant condenser, for example, water, and the refrigerant is condensed.

この冷媒により熱量を与えられた流体例えば水は冷媒の
温度より５〜１０℃低い温度に迄昇温されフラッシュに
より低圧水蒸気を発生させ、その蒸気を利用することが
できる。The fluid to which heat has been given by the refrigerant, such as water, is heated to a temperature 5 to 10 ° C. lower than the temperature of the refrigerant to generate low-pressure steam by flash, and the steam can be used.

本発明おいて、エチレンオキシド放散塔底部よりの高温
の液はエチレンオキシド吸収塔の底部からの低温の液と
熱交換し熱回収され、エチレンオキシド吸収塔へ供給さ
れる。In the present invention, the high temperature liquid from the bottom of the ethylene oxide diffusion column exchanges heat with the low temperature liquid from the bottom of the ethylene oxide absorption column to recover heat and is supplied to the ethylene oxide absorption column.

一方、エチレンオキシド吸収塔底液はエチレンオキシド
放散塔底部よりの高温の液と熱交換された後、気液分離
タンクにて軽質分ガスを分離した後、エチレンオキシド
放散塔頂部へ供給されてエチレンオキシドは放散され
る。本発明においてエチレンオキシド放散塔より放散さ
れるものは、大部分が水、エチレンオキシド、少部分が
二酸化炭素、微量の酸素、エチレン、不活性ガス（窒
素、アルゴン、メタン、エタン）、ホルムアルデヒド等
の低沸点不純物、アセトアルデヒドおよび酢酸等の高沸
点不純物からなる放散物である。On the other hand, the bottom liquid of the ethylene oxide absorption tower is heat-exchanged with the hot liquid from the bottom of the ethylene oxide stripping tower, and after separating the light component gas in the gas-liquid separation tank, it is supplied to the top of the ethylene oxide stripping tower to diffuse ethylene oxide. It In the present invention, what is released from the ethylene oxide stripping tower is mostly low-boiling point water, ethylene oxide, a small part carbon dioxide, a trace amount of oxygen, ethylene, an inert gas (nitrogen, argon, methane, ethane), formaldehyde and the like. It is a release product consisting of impurities, high boiling impurities such as acetaldehyde and acetic acid.

本発明をさらに詳しく述べるために図−１に基づいて説
明する。The present invention will be described with reference to FIG. 1 in order to describe the present invention in more detail.

図−１においてエチレンを銀触媒の存在下、分子状酸素
含有ガスにより接触気相酸化して生成するエチレンオキ
シドを含む反応生成ガスを導管（１）を通して、棚段塔
形式のエチレンオキシド吸収塔（２）の下部へ供給し、
導管（２４）よりエチレンオキシド吸収塔（２）の上部
へ、温度４０℃以下、pH＝６以上、エチレングリコール
濃度＝１〜２０重量％、消泡剤（水溶性シリコンエマル
ジョン）濃度＝１〜５０ppmおよび残部は水から成る吸
収液を導入し、反応生成ガスと向流接触させ反応生成ガ
ス中のエチレンオキシドを吸収液に吸収させる。ここで
反応生成ガス中の９９重量％以上のエチレンオキシドが
回収される。エチレンオキシド吸収塔（２）の塔頂部よ
り吸収しなかったエチレン、酸素、二酸化炭素、不活性
ガス（窒素、アルゴン、メタン、エタン）、アルデヒ
ド、酸性物質等のガスは導管（３）を通して炭酸ガス吸
収工程および／または酸化反応工程へ循環される。この
吸収工程においてエチレンオキシドの他、エチレン、酸
素、二酸化炭素、不活性ガス（窒素、アルゴン、メタ
ン、エタン、）ならびにエチレン酸化反応工程で生成し
たホルムアルデヒド等の低沸点不純物、アセトアルデヒ
ド、酢酸等の高沸点不純物もその実質量が同時に吸収さ
れる。In FIG. 1, a reaction product gas containing ethylene oxide produced by catalytic gas-phase oxidation of ethylene with a molecular oxygen-containing gas in the presence of a silver catalyst is passed through a conduit (1) and a tray column type ethylene oxide absorption tower (2). Supply to the bottom of
From the conduit (24) to the upper part of the ethylene oxide absorption tower (2), the temperature is 40 ° C or lower, pH = 6 or higher, ethylene glycol concentration = 1 to 20% by weight, defoaming agent (water-soluble silicone emulsion) concentration = 1 to 50 ppm, and An absorption liquid consisting of water is introduced into the balance and brought into countercurrent contact with the reaction product gas so that ethylene oxide in the reaction product gas is absorbed by the absorption liquid. Here, 99% by weight or more of ethylene oxide in the reaction product gas is recovered. Gases such as ethylene, oxygen, carbon dioxide, inert gases (nitrogen, argon, methane, ethane), aldehydes and acidic substances that have not been absorbed from the top of the ethylene oxide absorption tower (2) are absorbed through the conduit (3). It is recycled to the process and / or the oxidation reaction process. In this absorption process, in addition to ethylene oxide, ethylene, oxygen, carbon dioxide, inert gases (nitrogen, argon, methane, ethane, etc.) and low boiling impurities such as formaldehyde produced in the ethylene oxidation reaction process, high boiling points such as acetaldehyde and acetic acid. A substantial amount of impurities is absorbed at the same time.

エチレンオキシド吸収塔（２）の塔底液を導管（４）、
熱交換器（５）へ送りエチレンオキシド放散塔底液と熱
交換し温度７０〜１１０℃に高め、導管（６）により、
気液分離タンク（７）へ送られ、一部エチレンオキシ
ド、水を含む不活性ガスの軽質分ガスが導管（８）によ
り分離される。軽質分ガスをフラッシュした残部の吸収
液を導管（９）を通して圧力０．１〜１kg／cm2Ｇ、温
度９０〜１１０℃のエチレンオキシド放散塔（１０）の
上部へ供給し、エチレンオキシド放散塔（１０）の加熱
器（１２）へ導管（１３）を通して水蒸気またはダウサ
ム（米国ダウ社熱媒体商品）等の加熱媒体を供給して、
または直接エチレンオキシド放散塔の底部に水蒸気を導
入する加熱方式により、エチレンオキシドは放散され
る。エチレンオキシド放散塔（１０）の底部よりエチレ
ンオキシドを実質的に含まない温度１００〜１３０℃の
エチレンオキシド放散塔底液の一部は導管（１４）およ
び導管（１６）を通して熱交換器（５）に導入しエチレ
ンオキシド吸収塔底液と熱交換される。熱交換器（５）
を出た吸収液は冷媒蒸発器（５１）を経た後、冷却器
（１８）を通して、導管（２１）より水、導管（２２）
より水酸化カリウム水溶液および導管（２３）より消泡
剤（水溶性シリコンエマルジョン）を添加し、導管（２
４）を通してエチレンオキシド吸収塔（２）に導入する
ことができる。The bottom liquid of the ethylene oxide absorption tower (2) is introduced into the conduit (4),
It is sent to the heat exchanger (5) and heat-exchanged with the ethylene oxide stripping bottom liquid to raise the temperature to 70 to 110 ° C., and by the conduit (6),
It is sent to the gas-liquid separation tank (7), and a light component gas of an inert gas containing a part of ethylene oxide and water is separated by the conduit (8). The remaining absorption liquid after flushing the light gas is supplied to the upper portion of the ethylene oxide stripping tower (10) at a pressure of 0.1 to 1 kg / cm 2 G and a temperature of 90 to 110 ° C. through a conduit (9), and the ethylene oxide stripping tower (10 ) To a heater (12) through a conduit (13) to supply steam or a heating medium such as Dowsome (Dow Company heat medium product) to
Alternatively, ethylene oxide is diffused by a heating system in which steam is directly introduced into the bottom of the ethylene oxide stripping tower. From the bottom of the ethylene oxide stripping tower (10), a part of the bottom liquid of the ethylene oxide stripping tower at a temperature of 100 to 130 ° C. which does not substantially contain ethylene oxide is introduced into the heat exchanger (5) through the conduits (14) and (16). Heat exchange with the bottom liquid of the ethylene oxide absorption tower. Heat exchanger (5)
After passing through the refrigerant evaporator (51), the absorbing liquid that has exited passes through the cooler (18), water from the conduit (21), and the conduit (22).
Aqueous potassium hydroxide solution and an antifoaming agent (water-soluble silicone emulsion) are added from the conduit (23), and the conduit (2
It can be introduced into the ethylene oxide absorption tower (2) through 4).

一方、エチレンオキシド放散塔（１０）の塔底より導管
（１４）を通して抜き出した残部の吸収液は導管（１
５）を通して副生エチレングリコール濃縮塔に送ること
ができる。On the other hand, the remaining absorption liquid extracted from the bottom of the ethylene oxide stripping tower (10) through the conduit (14) is
It can be sent to a by-product ethylene glycol concentration tower through 5).

冷媒蒸発器（５１）でエチレンオキシド放散塔底部液と
熱交換し蒸発して冷媒は、導管（５２）を通して圧縮機
（５３）に送られ圧縮された後、導管（５４）を通して
冷媒凝縮器（５５）に送られ外部の流体に熱を与え凝縮
する。凝縮した冷媒は導管（５６）を通して再度冷媒蒸
発器（５１）へ送られる。The refrigerant evaporator (51) exchanges heat with the bottom liquid of the ethylene oxide stripping tower to evaporate, the refrigerant is sent to the compressor (53) through the conduit (52) and is compressed, and then the refrigerant condenser (55) is passed through the conduit (54). ) To heat the external fluid and condense it. The condensed refrigerant is sent again to the refrigerant evaporator (51) through the conduit (56).

冷媒凝縮器（５５）に導管（５７），導管（５８）およ
びタンク（５９）に導管（６２）より供給された水を循
環させることにより導管（６０）により水蒸気を回収す
ることができる。By circulating the water supplied from the conduit (57) to the refrigerant condenser (55), the conduit (58) and the tank (59) from the conduit (62), the steam can be recovered by the conduit (60).

この回収水蒸気はエチレンオキシド製造工程の加熱源に
有効に使用することができる。特にこの水蒸気はエチレ
ンオキシド蒸留塔に使用することができる。This recovered steam can be effectively used as a heat source in the ethylene oxide production process. In particular, this steam can be used in an ethylene oxide distillation column.

本発明をさらに詳しく述べるために従来公知の方法を図
−２に基づいて説明する。In order to describe the present invention in more detail, a conventionally known method will be described with reference to FIG.

図−２においてエチレンを銀触媒の存在下、分子状酸素
含有ガスにより接触気相酸化して生成するエチレンオキ
シドを含む反応生成ガスを導管（１）を通して、充分塔
あるいは棚段落形式のエチレンオキシド吸収塔（２）の
下部へ供給し、導管（２４）よりエチレンオキシド吸収
塔（２）の上部へ吸収液を導入し、反応生成ガスと向流
接触させ、反応生成ガス中の９９重量％以上のエチレン
オキシドを回収し、エチレンオキシド吸収塔（２）の塔
頂より吸収しなかったエチレン、酸素、二酸化炭素、不
活性ガス（窒素、アルゴン、メタン、エタン）、アルデ
ヒド、酸性物質等のガスは導管（３）を通して二酸化炭
素吸収工程および／または酸化反応工程へ循環される。
この吸収工程においてエチレンオキシドの他、エチレ
ン、酸素、二酸化炭素、不活性ガス（窒素、アルゴン、
メタン、エタン、）ならびにエチレン酸化反応工程で生
成したホルムアルデヒド等の低沸点不純物、アセトアル
デヒド、酢酸塔の高沸点不純物もその実質量が同時に吸
収される。エチレンオキシド吸収塔（２）の塔底液を導
管（４）を通して熱交換器（５）へ送りエチレンオキシ
ド放散塔底液と熱交換して温度７０〜１１０℃に高め、
導管（６）により気液分離タンク（７）へ送られ不活性
ガスが導管（８）により分離される。一部エチレンオキ
シド、水を含む吸収液は導管（９）を通して塔頂圧力
０．１〜１kg／cm2Ｇ、温度９０〜１１０℃のエチレン
オキシド放散塔（１０）の上部へ供給し、エチレンオキ
シド放散塔（１０）の加熱器（１２）より水蒸気または
ダウサム（ダウ社商品）等の加熱媒体で加熱するか、ま
たは直接エチレンオキシド放散塔（１０）の下部へ水蒸
気を導入する加熱方式により吸収液中に含まれるエチレ
ンオキシドの９９重量％以上を放散せしめ、エチレンオ
キシド放散塔（１０）の底部よりエチレンオキシドを実
質的に含まない温度１００〜１３０℃のエチレンオキシ
ド放散塔底液の一部は導管（１４）および導管（１６）
を通して熱交換器（５）でエチレンオキシド放散塔（１
０）の供給液と熱交換し、さらに冷却器（１８）により
冷却し、ついで吸収液中のエチレングリコール濃度を調
節するため新鮮な水を導管（２１）を通して導入し、吸
収液中のpHを調節するための導管（２２）を通してアル
カリを添加し、吸収液中の消泡剤濃度を調節するため導
管（２３）を通して消泡剤を導入することができる。エ
チレンを分子状酸素で酸化する酸化工程およびエチレン
オキシド放散工程の間で吸収液中にエチレンオキシドと
水との加水反応で生成する副生エチレングリコールおよ
びホルムアルデヒド等の低沸点不純物、アセトアルデヒ
ドおよび酢酸等の高沸点不純物の増加を防ぐためエチレ
ンオキシド放散塔（１０）の塔底部より導管（１４）お
よび（１５）を通してエチレンオキシド放散塔（１０）
の塔底液を抜き出し、濃縮工程に送られる。In FIG. 2, a reaction product gas containing ethylene oxide produced by catalytic gas-phase oxidation of ethylene with a molecular oxygen-containing gas in the presence of a silver catalyst is passed through a conduit (1) and a sufficient tower or a column-type ethylene oxide absorption tower ( It is supplied to the lower part of 2) and the absorption liquid is introduced from the conduit (24) to the upper part of the ethylene oxide absorption tower (2) and brought into countercurrent contact with the reaction product gas to recover 99% by weight or more of ethylene oxide in the reaction product gas. However, gases such as ethylene, oxygen, carbon dioxide, inert gases (nitrogen, argon, methane, ethane), aldehydes and acidic substances that have not been absorbed from the top of the ethylene oxide absorption tower (2) are oxidized through the conduit (3). It is recycled to the carbon absorption step and / or the oxidation reaction step.
In this absorption process, in addition to ethylene oxide, ethylene, oxygen, carbon dioxide, inert gas (nitrogen, argon,
Methane, ethane,) and low boiling point impurities such as formaldehyde produced in the ethylene oxidation reaction step, acetaldehyde, and high boiling point impurities in the acetic acid column are also absorbed in substantial amounts. The bottom liquid of the ethylene oxide absorption tower (2) is sent to the heat exchanger (5) through the conduit (4) and heat-exchanged with the bottom liquid of the ethylene oxide diffusion tower to raise the temperature to 70 to 110 ° C.
The inert gas is sent to the gas-liquid separation tank (7) by the conduit (6) and separated by the conduit (8). The absorption liquid containing a part of ethylene oxide and water is supplied to the upper part of the ethylene oxide diffusion tower (10) at a tower top pressure of 0.1 to 1 kg / cm 2 G and a temperature of 90 to 110 ° C. through a conduit (9), and the ethylene oxide diffusion tower ( It is contained in the absorbing solution by heating with steam or a heating medium such as Dowsome (commercially available from Dow) from the heater (12) of 10) or by a heating system in which steam is directly introduced into the lower part of the ethylene oxide stripping tower (10). 99% by weight or more of ethylene oxide is diffused and a part of the bottom liquid of the ethylene oxide diffusion tower (10) at a temperature of 100 to 130 ° C. substantially free of ethylene oxide is a conduit (14) and a conduit (16).
Through an ethylene oxide stripping tower (1
0) heat exchange with the feed liquid, further cooling by a cooler (18), and then fresh water is introduced through a conduit (21) to adjust the ethylene glycol concentration in the absorption liquid to adjust the pH in the absorption liquid. The alkali can be added through the adjusting conduit (22) and the antifoaming agent can be introduced through the conduit (23) to adjust the concentration of the antifoaming agent in the absorbing liquid. Low boiling point impurities such as by-produced ethylene glycol and formaldehyde, and high boiling points such as acetaldehyde and acetic acid produced by the hydrolysis reaction of ethylene oxide and water in the absorption liquid between the oxidation step of oxidizing ethylene with molecular oxygen and the ethylene oxide emission step In order to prevent the increase of impurities, the ethylene oxide stripping tower (10) is passed through the conduits (14) and (15) from the bottom of the ethylene oxide stripping tower (10).
The bottom liquid of the above is withdrawn and sent to the concentration step.

（実施例） 以下、実施例により本発明をさらに詳細に説明する。し
かし本発明はこの実施例のみによって本発明の範囲を規
制するものでない。(Examples) Hereinafter, the present invention will be described in more detail with reference to Examples. However, the present invention does not limit the scope of the present invention by this embodiment alone.

実施例１ 図−１においてエチレンを銀触媒の存在下、分子状酸素
含有ガスにより接触気相酸化して生成するエチレンオキ
シドを含む反応生成ガスを導管（１）を通して、棚段塔
形式のエチレンオキシド吸収塔（２）の下部へ供給し、
導管（２４）よりエチレンオキシド吸収塔（２）の上部
へ、温度４０℃以下、pH＝６以上、エチレングリコール
濃度＝１〜２０重量％、消泡剤（水溶性シリコンエマル
ジョン）濃度＝１〜５０ppmおよび残部は水から成る吸
収液を導入し、反応生成ガスと向流接触させ反応生成ガ
ス中のエチレンオキシドを吸収液に吸収させた。ここで
反応生成ガス中の９９重量％以上のエチレンオキシドが
回収された。エチレンオキシド吸収塔（２）の塔頂より
吸収しなかったエチレン、酸素、二酸化炭素、不活性ガ
ス（窒素、アルゴン、メタン、エタン）、アルデヒド、
酸性物質等の不純物塔のガスは導管（３）を通して炭酸
ガス吸収工程および／または酸化反応工程へ循環した。Example 1 In FIG. 1, a reaction product gas containing ethylene oxide produced by catalytic gas-phase oxidation of ethylene with a molecular oxygen-containing gas in the presence of a silver catalyst is passed through a conduit (1) and a tray column type ethylene oxide absorption tower is provided. Supply to the bottom of (2),
From the conduit (24) to the upper part of the ethylene oxide absorption tower (2), the temperature is 40 ° C or lower, pH = 6 or higher, ethylene glycol concentration = 1 to 20% by weight, defoaming agent (water-soluble silicone emulsion) concentration = 1 to 50 ppm, and An absorption liquid consisting of water was introduced into the balance and brought into countercurrent contact with the reaction product gas so that the ethylene oxide in the reaction product gas was absorbed by the absorption liquid. Here, 99% by weight or more of ethylene oxide in the reaction product gas was recovered. Ethylene, oxygen, carbon dioxide, inert gas (nitrogen, argon, methane, ethane), aldehyde, which was not absorbed from the top of the ethylene oxide absorption tower (2),
The gas in the impurity column such as the acidic substance was circulated to the carbon dioxide absorption step and / or the oxidation reaction step through the conduit (3).

この吸収工程においてエチレンオキシドの他、エチレ
ン、酸素、二酸化炭素、不活性ガス（窒素、アルゴン、
メタン、エタン、）ならびにエチレン酸化反応工程で生
成したホルムアルデヒド等の低沸点不純物、アセトアル
デヒド、酢酸等の高沸点不純物もその実質量が同時に吸
収された。In this absorption process, in addition to ethylene oxide, ethylene, oxygen, carbon dioxide, inert gas (nitrogen, argon,
Methane, ethane,) and low boiling point impurities such as formaldehyde produced in the ethylene oxidation reaction step and high boiling point impurities such as acetaldehyde and acetic acid were also absorbed in substantial amounts.

エチレンオキシド吸収塔（２）の塔底液を導管（４）を
通して、熱交換器（５）へ送りエチレンオキシド放散塔
底液と熱交換し温度７０〜１１０℃に高め、導管（６）
により、気液分離タンク（７）へ送られ、一部エチレン
オキシド、水を含む不活性ガスの軽質分ガスが導管
（８）により分離した。軽質分ガスをフラッシュした残
部の吸収液を導管（９）を通して圧力０．１〜１kg／cm
2Ｇ、温度９０〜１１０℃のエチレンオキシド放散塔
（１０）の上部へ供給し、エチレンオキシド放散塔（１
０）の加熱器（１２）へ導管（１３）を通して加熱用水
蒸気を供給する加熱方式によりエチレンオキシドは放散
した。エチレンオキシド放散塔（１０）の底部よりエチ
レンオキシドを実質的に含まない温度１００〜１３０℃
のエチレンオキシド放散塔底液の一部は導管（１４）お
よび導管（１６）を通して熱交換器（５）に導入しエチ
レンオキシド吸収塔底液と熱交換した。熱交換器（５）
を出た吸収液は冷媒蒸発器（５１）を経た後、冷却器
（１８）を通して、導管（２１）より水、導管（２２）
より水酸化カルシウム水溶液および導管（２３）より消
泡剤（水溶性シリコンエマルジョン）を添加し、導管
（２４）を通してエチレンオキシド吸収塔（２）に導入
した。The bottom liquid of the ethylene oxide absorption tower (2) is sent to the heat exchanger (5) through the conduit (4) to exchange heat with the bottom liquid of the ethylene oxide diffusion tower to raise the temperature to 70 to 110 ° C., and the conduit (6)
Thus, the light component gas of the inert gas partially sent to the gas-liquid separation tank (7) and containing ethylene oxide and water was separated by the conduit (8). The remaining absorption liquid after flushing the light gas is passed through the conduit (9) and the pressure is 0.1 to 1 kg / cm.
It is fed to the upper part of the ethylene oxide diffusion tower (10) at 2 G and a temperature of 90 to 110 ° C.
Ethylene oxide was diffused by the heating system in which heating steam was supplied to the heater (12) of (0) through the conduit (13). From the bottom of the ethylene oxide stripping tower (10), a temperature of 100 to 130 ° C. which does not substantially contain ethylene oxide.
A part of the bottom liquid of the ethylene oxide desorption column was introduced into the heat exchanger (5) through the conduit (14) and the conduit (16) and exchanged heat with the bottom liquid of the ethylene oxide absorption column. Heat exchanger (5)
After passing through the refrigerant evaporator (51), the absorbing liquid that has exited passes through the cooler (18), water from the conduit (21), and the conduit (22).
An aqueous solution of calcium hydroxide and an antifoaming agent (water-soluble silicone emulsion) were added from a conduit (23) and introduced into the ethylene oxide absorption tower (2) through a conduit (24).

一方、エチレンオキシド放散塔（１０）の塔底より導管
（１４）を通して抜き出した残部の吸収液は導管（１
５）を通して副生エチレングリコール濃縮塔に送った。On the other hand, the remaining absorption liquid extracted from the bottom of the ethylene oxide stripping tower (10) through the conduit (14) is
It sent to the ethylene glycol concentration tower by-product through 5).

冷媒蒸発器（５１）でエチレンオキシド放散塔底部液と
熱交換し蒸発して冷媒は、導管（５２）を通して冷媒圧
縮機（５３）に送られ圧縮された後、導管（５４）を通
して冷媒凝縮器（５５）に送られ外部の流体に熱を与え
凝縮させた。凝縮した冷媒は導管（５６）を通して再度
冷媒蒸発器（５１）へ送った。The refrigerant evaporator (51) exchanges heat with the liquid at the bottom of the ethylene oxide stripping tower and evaporates, and the refrigerant is sent to the refrigerant compressor (53) through the conduit (52) and compressed, and then the refrigerant condenser (through the conduit (54) ( 55) to heat the external fluid to condense it. The condensed refrigerant was sent again to the refrigerant evaporator (51) through the conduit (56).

冷媒凝縮器（５５）に導管（５７），導管（５８）およ
びタンク（５９）に導管（６２）より供給された水を循
環させることにより導管（６０）により水蒸気を回収し
た。Water vapor was recovered through the conduit (60) by circulating the water supplied through the conduit (57) and the conduit (58) to the refrigerant condenser (55) and the tank (59) through the conduit (62).

表−１にこのプロセスの連続操作条件を一括して表示す
る。Table 1 shows the continuous operating conditions of this process all together.

比較例１ 図−２においてエチレンを銀触媒の存在下、分子状酸素
含有ガスにより接触気相酸化して生成するエチレンオキ
シドを含む反応生成ガスを導管（１）を通して、棚段塔
形式のエチレンオキシド吸収塔（２）の下部へ供給し、
導管（２４）よりエチレンオキシド吸収塔（２）の上部
へ吸収液を導入し、温度２９．６℃、pH＝６、エチレン
グリコール濃度＝９．０重量％、消泡剤（水溶性シリコ
ンエマルジョン）濃度＝３ppmおよび、残部は水から成
る吸収液を導入し、反応生成ガスと向流接触させ反応生
成ガス中のエチレンオキシドを吸収液に吸収させた。エ
チレンオキシド吸収塔（２）の塔頂部より吸収しなかっ
たエチレン、酸素、二酸化炭素、不活性ガス（窒素、ア
ルゴン、メタン、エタン）、アルデヒド類、酸性物質等
のガスは導管（３）を通して炭酸ガス吸収工程および／
または酸化反応工程へ循環した。エチレンオキシド吸収
塔（４）の塔底液を導管（４）、熱交換器（５）、導管
（６）により、気液分離タンク（７）へ送り、一部エチ
レンオキシド、水を含む不活性ガスが導管（８）により
分離した。軽質分ガスをフラッシュした残部の吸収液を
導管（９）を通してエチレンオキシド放散塔（１０）の
上部へ供給した。エチレンオキシド放散塔（１０）の加
熱器（１２）へ導管（１３）を通して水蒸気を供給して
加熱し、エチレンオキシド放散塔（１０）の底部より実
質的にでエチレンオキシドを含まないエチレンオキシド
放散塔底液を導管（１４）を通して抜き出し、熱交換器
（５）および冷却器（１８）を通して、導管（２１）よ
り水、導管（２２）より水酸化カリウム水溶液および導
管（２３）より消泡剤（水溶性シリコンエマルジョン）
を添加した。Comparative Example 1 In FIG. 2, a reaction product gas containing ethylene oxide produced by catalytic gas-phase oxidation of ethylene with a molecular oxygen-containing gas in the presence of a silver catalyst is passed through a conduit (1), and a tray column type ethylene oxide absorption tower is provided. Supply to the bottom of (2),
The absorption liquid was introduced into the upper part of the ethylene oxide absorption tower (2) through the conduit (24), and the temperature was 29.6 ° C., pH = 6, ethylene glycol concentration = 9.0% by weight, defoaming agent (water-soluble silicone emulsion) concentration. = 3 ppm, and the balance was water, and the absorption liquid was introduced and brought into countercurrent contact with the reaction product gas so that the ethylene oxide in the reaction product gas was absorbed by the absorption liquid. Gases such as ethylene, oxygen, carbon dioxide, inert gases (nitrogen, argon, methane, ethane), aldehydes, and acidic substances that have not been absorbed from the top of the ethylene oxide absorption tower (2) are carbon dioxide gas through the conduit (3). Absorption process and /
Alternatively, it was recycled to the oxidation reaction step. The bottom liquid of the ethylene oxide absorption tower (4) is sent to a gas-liquid separation tank (7) through a conduit (4), a heat exchanger (5) and a conduit (6), and an inert gas containing a part of ethylene oxide and water is generated. Separated by conduit (8). The remaining absorption liquid after flushing the light gas was fed to the upper part of the ethylene oxide stripping column (10) through the conduit (9). Water vapor is supplied to the heater (12) of the ethylene oxide stripping tower (10) through the conduit (13) to heat the ethylene oxide stripping tower (10) from the bottom of the ethylene oxide stripping tower (10) and the ethylene oxide stripping tower bottom liquid substantially containing no ethylene oxide is piped. (14), and through the heat exchanger (5) and the cooler (18), water from the conduit (21), an aqueous potassium hydroxide solution from the conduit (22), and an antifoaming agent (water-soluble silicone emulsion) from the conduit (23). )
Was added.

一方、エチレンオキシド放散塔（１０）の塔底より導管
（１４）を通して抜き出した残部の吸収液は導管（１
５）を通して副生エチレングリコール濃縮塔に送った。On the other hand, the remaining absorption liquid extracted from the bottom of the ethylene oxide stripping tower (10) through the conduit (14) is
It sent to the ethylene glycol concentration tower by-product through 5).

表−２にこのプロセスの操作条件を一括して表示する。Table 2 shows the operating conditions of this process all together.

（発明の効果） 本発明によればエチレンオキシド放散塔底部から出てエ
チレンオキシド吸収塔底液と熱交換器により熱回収され
たエチレンオキシドを実質的に含まない、温度５０〜６
０℃のエチレンオキシド放散塔底部液から圧縮式ヒート
ポンプにより低圧蒸気として熱量を回収することが出来
る。さらにこの方法を実施することによりエチレンオキ
シド吸収塔に送る吸収液を冷却する冷却水の熱負荷が低
減される効果を有するものである。 (Effects of the Invention) According to the present invention, the ethylene oxide absorption tower bottom liquid which is discharged from the bottom of the ethylene oxide diffusion tower and the ethylene oxide which is heat-recovered by the heat exchanger are substantially free from the temperature of 50 to 6
The amount of heat can be recovered as low-pressure steam from a liquid at the bottom of the ethylene oxide stripping tower at 0 ° C. by a compression heat pump. Further, by carrying out this method, the heat load of the cooling water for cooling the absorption liquid sent to the ethylene oxide absorption tower is reduced.

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

図−１は、本発明のエチレンオキシド回収方法の好まし
い具体例を示す一例である。 図−２は、本発明に関連する公知のエチレンキシド回収
方法を示す一例である。 （２）エチレンオキシド吸収塔 （５）熱交換器 （７）気液分離タンク （１０）エチレンオキシド放散塔 （１２）加熱器 （１８）冷却器 （５１）冷媒蒸発器 （５３）冷媒圧縮機 （５５）冷媒凝縮器 （５９）フラッシュタンクFIG. 1 is an example showing a preferred specific example of the ethylene oxide recovery method of the present invention. FIG. 2 is an example showing a known ethylene oxide recovery method related to the present invention. (2) Ethylene oxide absorption tower (5) Heat exchanger (7) Gas-liquid separation tank (10) Ethylene oxide diffusion tower (12) Heater (18) Cooler (51) Refrigerant evaporator (53) Refrigerant compressor (55) Refrigerant condenser (59) Flash tank

Claims (1)

【特許請求の範囲】[Claims] 【請求項１】エチレンを銀触媒の存在下、分子状酸素含
有ガスと接触気相酸化して生成したエチレンオキシドを
含有する反応生成ガスをエチレンオキシド吸収塔へ導入
して吸収液と向流接触させ、エチレンオキシド吸収塔頂
部よりのガスは炭酸ガス吸収工程および／またはエチレ
ン酸化反応工程へ循環し、エチレンオキシドを含む吸収
塔底液はエチレンオキシド放散塔へ供給し、エチレンオ
キシド放散塔頂部からエチレンオキシドを放散せしめ、
エチレンオキシド放散塔底部より抜き出した液はエチレ
ンオキシド吸収塔および副生エチレングリコール濃縮塔
へ送る工程において、エチレンオキシド放散塔底部より
抜き出した液を熱交換器にてエチレンオキシド吸収塔底
液と熱交換した後、冷媒蒸発器に送り、冷媒蒸発器でエ
チレンオキシド放散塔底部液と熱交換し蒸発した冷媒
は、圧縮機で圧縮された後、冷媒凝縮器に送り、該冷媒
凝縮器に水を循環させることにより水蒸気を回収し、冷
媒蒸発器により冷却された吸収液をさらに冷却器にて冷
却した後、エチレンオキシド吸収塔の吸収液とすること
を特徴とするエチレンオキシドの回収方法。1. A reaction product gas containing ethylene oxide produced by catalytic vapor-phase oxidation of ethylene with a molecular oxygen-containing gas in the presence of a silver catalyst is introduced into an ethylene oxide absorption tower and brought into countercurrent contact with the absorbing liquid. The gas from the top of the ethylene oxide absorption tower is circulated to the carbon dioxide absorption step and / or the ethylene oxidation reaction step, the absorption tower bottom liquid containing ethylene oxide is supplied to the ethylene oxide diffusion tower, and ethylene oxide is diffused from the ethylene oxide diffusion tower top,
The liquid extracted from the bottom of the ethylene oxide stripping tower is sent to the ethylene oxide absorption tower and the by-product ethylene glycol concentrating tower in the step of transferring the liquid extracted from the bottom of the ethylene oxide stripping tower to the ethylene oxide absorption tower bottom liquid in a heat exchanger, and then the refrigerant. The refrigerant sent to the evaporator, heat-exchanged with the liquid at the bottom of the ethylene oxide stripping tower in the refrigerant evaporator, and evaporated, is compressed by the compressor and then sent to the refrigerant condenser to circulate water through the refrigerant condenser to generate steam. A method for recovering ethylene oxide, characterized in that the absorption liquid recovered and cooled by the refrigerant evaporator is further cooled by the cooling device and then used as the absorption liquid of the ethylene oxide absorption tower.
JP60152436A 1985-07-12 1985-07-12 Recovery method of ethylene oxide Expired - Lifetime JPH0655733B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP60152436A JPH0655733B2 (en) 1985-07-12 1985-07-12 Recovery method of ethylene oxide

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP60152436A JPH0655733B2 (en) 1985-07-12 1985-07-12 Recovery method of ethylene oxide

Publications (2)

Publication Number Publication Date
JPS6216472A JPS6216472A (en) 1987-01-24
JPH0655733B2 true JPH0655733B2 (en) 1994-07-27

Family

ID=15540490

Family Applications (1)

Application Number Title Priority Date Filing Date
JP60152436A Expired - Lifetime JPH0655733B2 (en) 1985-07-12 1985-07-12 Recovery method of ethylene oxide

Country Status (1)

Country Link
JP (1) JPH0655733B2 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7021357B2 (en) * 2018-08-10 2022-02-16 株式会社日本触媒 Method for Producing Ethylene Oxide and Ethylene Glycol

Also Published As

Publication number Publication date
JPS6216472A (en) 1987-01-24

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