JP7513398B2 - Method for purifying (meth)acrylonitrile and method for producing (meth)acrylonitrile - Google Patents
Method for purifying (meth)acrylonitrile and method for producing (meth)acrylonitrile Download PDFInfo
- Publication number
- JP7513398B2 JP7513398B2 JP2020005954A JP2020005954A JP7513398B2 JP 7513398 B2 JP7513398 B2 JP 7513398B2 JP 2020005954 A JP2020005954 A JP 2020005954A JP 2020005954 A JP2020005954 A JP 2020005954A JP 7513398 B2 JP7513398 B2 JP 7513398B2
- Authority
- JP
- Japan
- Prior art keywords
- condenser
- height position
- distillation column
- reflux
- distillation
- 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.)
- Active
Links
- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 title claims description 53
- 238000000034 method Methods 0.000 title claims description 50
- 238000004519 manufacturing process Methods 0.000 title claims description 14
- 238000004821 distillation Methods 0.000 claims description 181
- LELOWRISYMNNSU-UHFFFAOYSA-N hydrogen cyanide Chemical compound N#C LELOWRISYMNNSU-UHFFFAOYSA-N 0.000 claims description 146
- 238000010992 reflux Methods 0.000 claims description 118
- 239000007789 gas Substances 0.000 claims description 38
- 238000000746 purification Methods 0.000 claims description 38
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 17
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 10
- 239000002994 raw material Substances 0.000 claims description 9
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 claims description 8
- 229910021529 ammonia Inorganic materials 0.000 claims description 5
- 238000010438 heat treatment Methods 0.000 claims description 5
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 claims description 5
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 claims description 5
- 239000003054 catalyst Substances 0.000 claims description 4
- 239000001294 propane Substances 0.000 claims description 4
- VQTUBCCKSQIDNK-UHFFFAOYSA-N Isobutene Chemical group CC(C)=C VQTUBCCKSQIDNK-UHFFFAOYSA-N 0.000 claims description 3
- DKGAVHZHDRPRBM-UHFFFAOYSA-N Tert-Butanol Chemical compound CC(C)(C)O DKGAVHZHDRPRBM-UHFFFAOYSA-N 0.000 claims description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 3
- 239000001301 oxygen Substances 0.000 claims description 3
- 229910052760 oxygen Inorganic materials 0.000 claims description 3
- 239000007788 liquid Substances 0.000 description 14
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 12
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 description 12
- 230000018044 dehydration Effects 0.000 description 12
- 238000006297 dehydration reaction Methods 0.000 description 12
- 239000000243 solution Substances 0.000 description 11
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N Hydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 description 8
- 238000006116 polymerization reaction Methods 0.000 description 7
- 239000001257 hydrogen Substances 0.000 description 6
- 229910052739 hydrogen Inorganic materials 0.000 description 6
- 125000004435 hydrogen atom Chemical class [H]* 0.000 description 6
- 239000002253 acid Substances 0.000 description 4
- 238000005381 potential energy Methods 0.000 description 3
- 238000010926 purge Methods 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- AEMRFAOFKBGASW-UHFFFAOYSA-N Glycolic acid Chemical compound OCC(O)=O AEMRFAOFKBGASW-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 238000009833 condensation Methods 0.000 description 2
- 230000005494 condensation Effects 0.000 description 2
- 238000011109 contamination Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000007599 discharging Methods 0.000 description 2
- 239000003595 mist Substances 0.000 description 2
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- VVQNEPGJFQJSBK-UHFFFAOYSA-N Methyl methacrylate Chemical compound COC(=O)C(C)=C VVQNEPGJFQJSBK-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 229910001882 dioxygen Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- XAEFZNCEHLXOMS-UHFFFAOYSA-M potassium benzoate Chemical compound [K+].[O-]C(=O)C1=CC=CC=C1 XAEFZNCEHLXOMS-UHFFFAOYSA-M 0.000 description 1
- 159000000000 sodium salts Chemical class 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C253/00—Preparation of carboxylic acid nitriles
- C07C253/32—Separation; Purification; Stabilisation; Use of additives
- C07C253/34—Separation; Purification
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
- C01C3/00—Cyanogen; Compounds thereof
- C01C3/02—Preparation, separation or purification of hydrogen cyanide
- C01C3/0208—Preparation in gaseous phase
- C01C3/0212—Preparation in gaseous phase from hydrocarbons and ammonia in the presence of oxygen, e.g. the Andrussow-process
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
- C01C3/00—Cyanogen; Compounds thereof
- C01C3/02—Preparation, separation or purification of hydrogen cyanide
- C01C3/0295—Purification
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C253/00—Preparation of carboxylic acid nitriles
- C07C253/24—Preparation of carboxylic acid nitriles by ammoxidation of hydrocarbons or substituted hydrocarbons
- C07C253/26—Preparation of carboxylic acid nitriles by ammoxidation of hydrocarbons or substituted hydrocarbons containing carbon-to-carbon multiple bonds, e.g. unsaturated aldehydes
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Toxicology (AREA)
- Inorganic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
本発明は、（メタ）アクリロニトリルの精製方法及び（メタ）アクリロニトリルの製造方法に関する。 The present invention relates to a method for purifying (meth)acrylonitrile and a method for producing (meth)acrylonitrile.
プロピレン及び／又はプロパン、アンモニア並びに分子状酸素を触媒の存在下に反応させてアクリロニトリルを製造するプロセスにおいて、生成したアクリロニトリル、アセトニトリル、青酸及び水から、アセトニトリルを分離した後、蒸留操作により青酸及び水を分離することによりアクリロニトリルを回収する。この蒸留塔は、脱青酸脱水塔と呼ばれる。脱青酸脱水塔の上部（脱青酸部）では青酸が重合したり、脱青酸脱水塔の下部（脱水部）ではアクリロニトリルが重合したりすることに起因してトレイが閉塞して詰まり、蒸留塔を長期的に安定に運転することが困難となることがある。 In the process of producing acrylonitrile by reacting propylene and/or propane, ammonia, and molecular oxygen in the presence of a catalyst, acetonitrile is separated from the resulting acrylonitrile, acetonitrile, hydrocyanic acid, and water, and then acrylonitrile is recovered by separating the hydrocyanic acid and water by distillation. This distillation tower is called a hydrocyanic acid removal dehydration tower. Polymerization of hydrocyanic acid in the upper part of the hydrocyanic acid removal dehydration tower (hydrocyanic acid removal section) and polymerization of acrylonitrile in the lower part of the hydrocyanic acid removal dehydration tower (dehydration section) can cause trays to become clogged and blocked, making it difficult to operate the distillation tower stably over the long term.
蒸留塔でのアクリロニトリル及び青酸の重合を防止するために、例えば、特許文献１に記載のようにハイドロキノン及び酢酸を蒸留塔の塔液中に特定値以上となるように添加することが考えられる。これにより、アクリロニトリル及び青酸の重合が抑制される。 To prevent polymerization of acrylonitrile and hydrocyanic acid in the distillation tower, it is possible to add hydroquinone and acetic acid to the liquid of the distillation tower so that the amount is equal to or greater than a specific value, as described in Patent Document 1. This suppresses polymerization of acrylonitrile and hydrocyanic acid.
上記プロセスにおいて、脱青酸脱水塔に供給され、（メタ）アクリロニトリル、シアン化水素及び水を含む溶液を加熱することにより生成したガスを脱青酸脱水塔から凝縮器に供給し、凝縮器において上記ガスを凝縮させることにより生成した凝縮液を脱青酸脱水塔に還流させることがある。この還流工程において、通常、凝縮液を脱青酸脱水塔に効率よく還流させるためにポンプ等を用いることが考えられるが、この場合、シアン化水素が外部に漏洩する虞がある。また、ポンプ等を用いる場合には、詰まり防止用のパージ水が必要であるが、パージ水に起因するシアン化水素の重合促進により、脱青酸脱水塔内でトレイが閉塞してつまり、蒸留塔を長期的に安定に運転できない虞がある。 In the above process, the gas generated by heating the solution containing (meth)acrylonitrile, hydrogen cyanide, and water supplied to the hydrogen cyanide removal dehydration tower is supplied to a condenser from the hydrogen cyanide removal dehydration tower, and the condensate generated by condensing the gas in the condenser is refluxed to the hydrogen cyanide removal dehydration tower. In this reflux process, a pump or the like is usually used to efficiently reflux the condensate to the hydrogen cyanide removal dehydration tower, but in this case, there is a risk of hydrogen cyanide leaking to the outside. In addition, when a pump or the like is used, purging water is required to prevent clogging, but the polymerization of hydrogen cyanide promoted by the purging water may cause trays to become clogged in the hydrogen cyanide removal dehydration tower, which may prevent the distillation tower from operating stably for a long period of time.
従って、本発明の目的は、（メタ）アクリロニトリル又はシアン化水素の精製工程において、ポンプ等を用いなくても、効率よく還流可能であり、（メタ）アクリロニトリル又はシアン化水素が漏洩を抑制したり、脱青酸脱水塔のトレイの汚れによる閉塞を抑制したりすることにより長期間安定に運転可能な（メタ）アクリロニトリル又はシアン化水素の精製方法及びこれに用いる蒸留装置を提供することにある。 The object of the present invention is therefore to provide a method for purifying (meth)acrylonitrile or hydrogen cyanide, which allows efficient reflux without the use of pumps or the like in the purification process of (meth)acrylonitrile or hydrogen cyanide, and which can be operated stably for a long period of time by suppressing leakage of (meth)acrylonitrile or hydrogen cyanide and by suppressing clogging of the trays of the hydrogen cyanide removal dehydration tower due to contamination, and a distillation apparatus used therein.
本発明者らは鋭意検討した結果、蒸留塔と、該蒸留塔と連結した凝縮器と、凝縮器の出口から蒸留塔に凝縮液を還流するための還流配管と、を備えた蒸留装置において、蒸留塔、凝縮器及び還流配管の接続構造を特定の構造とすることにより、、上記課題を解決できることを見出し、本発明を完成するに至った。 After extensive research, the inventors discovered that the above problems could be solved by using a specific connection structure for the distillation tower, condenser, and reflux pipe in a distillation apparatus equipped with a distillation tower, a condenser connected to the distillation tower, and a reflux pipe for refluxing the condensate from the outlet of the condenser to the distillation tower, and thus completed the present invention.
すなわち、本発明は以下の通りである。
［１］
蒸留塔と、該蒸留塔と連結した凝縮器とを備えた蒸留装置を用いて、（メタ）アクリロニトリル、シアン化水素及び水を含む溶液から（メタ）アクリロニトリル又はシアン化水素を精製する精製方法であって、
前記蒸留塔に供給された前記溶液を加熱することにより生成したガスを、前記蒸留塔から、前記凝縮器に供給する供給工程と、
該供給工程により供給されたガスを凝縮させることにより生成した凝縮液を、前記凝縮器の出口から、前記蒸留塔に還流する還流工程とを含み、
前記凝縮器の出口から前記蒸留塔に前記凝縮液を還流するための還流配管を備えており、前記還流配管の一端が、前記凝縮器の出口と接続しており、前記還流配管の他端が、前記蒸留塔の上部と接続しており、前記凝縮器の出口が、前記凝縮器の下部に位置しており、前記還流工程において、前記還流配管を介して前記凝縮液を前記凝縮器の出口から前記蒸留塔の上部に供給する、
（メタ）アクリロニトリル又はシアン化水素の精製方法。
［２］
前記蒸留装置が、前記蒸留塔から前記凝縮器に前記ガスを供給するための供給配管を備えており、前記供給配管の一端が、前記蒸留塔の塔頂部と接続しており、前記供給配管の他端が、前記凝縮器の上部と接続しており、
前記供給工程において、前記供給配管を介して前記ガスを前記蒸留塔の塔頂部から前記凝縮器の上部に供給する、上記［１］記載の精製方法。
［３］
前記蒸留装置の前記凝縮器の出口の高さ位置が、前記蒸留塔の最上端の高さ位置よりも高く形成されている、上記［１］又は［２］記載の精製方法。
［４］
前記凝縮器の出口の高さ位置と前記蒸留塔の最上端の高さ位置との距離が１０～１０００ｃｍである、上記［３］に記載の精製方法。
［５］
前記凝縮器の出口の高さ位置と前記蒸留塔の最上端高さ位置との距離が１０～５００ｃｍである、上記［３］に記載の精製方法。
［６］
前記凝縮器の出口の高さ位置と前記蒸留塔の最上端高さ位置との距離が１０～３００ｃｍである、上記［３］に記載の精製方法。
［７］
前記蒸留装置が、前記凝縮器の出口から前記蒸留塔に前記凝縮液を還流するための還流配管を備えており、前記還流配管の最下端の高さ位置が、前記蒸留塔の前記還流配管の接続口の高さ位置よりも低く形成されており、
前記還流工程において、前記還流配管を介して前記凝縮液を前記凝縮器の出口から前記蒸留塔に供給する、上記［１］～［６］のいずれかに記載の精製方法。
［８］
前記還流配管の最下端の高さ位置が、前記蒸留塔の前記還流配管の接続口高さ位置よりも１０ｃｍ以上低い、上記［７］に記載の精製方法。
［９］
前記還流配管の最下端の高さ位置が、前記蒸留塔の前記還流配管の接続口高さ位置よりも１００ｃｍ以上低い、上記［７］に記載の精製方法。
［１０］
前記蒸留塔の外部に前記凝縮器が設置されている、上記［１］～［９］のいずれかに記載の精製方法。
［１１］
原料ガス、アンモニア及び酸素を触媒の存在下でアンモ酸化反応させることにより（メタ）アクリロニトリルを製造する方法であって、
（メタ）アクリロニトリル、シアン化水素及び水を含む溶液から（メタ）アクリロニトリル又はシアン化水素を精製する精製工程を含み、
前記精製工程が、上記［１］～［１０］のいずれかに記載の精製方法を用いる、（メタ）アクリロニトリル又はシアン化水素の製造方法。
［１２］
前記原料ガスが、プロパン、プロピレン、イソブチレン、及びターシャリーブチルアルコールからなる群から選択される１種以上である、上記［１１］記載の（メタ）アクリロニトリル又はシアン化水素の製造方法。
［１３］
蒸留塔と、該蒸留塔と連結した凝縮器とを備え、（メタ）アクリロニトリル、シアン化水素及び水を含む溶液から（メタ）アクリロニトリル又はシアン化水素を精製する蒸留装置であって、
前記凝縮器の出口から前記蒸留塔に凝縮液を還流するための還流配管を備えており、前記還流配管の一端が、前記凝縮器の出口と接続しており、前記還流配管の他端が、前記蒸留塔の上部と接続しており、前記凝縮器の出口が、前記凝縮器の下部に位置している、（メタ）アクリロニトリル又はシアン化水素を精製する蒸留装置。
［１４］
前記蒸留装置が、前記蒸留塔から前記凝縮器にガスを供給するための供給配管を備えており、前記供給配管の一端が、前記蒸留塔の塔頂部と接続しており、前記供給配管の他端が、前記凝縮器の上部と接続している、［１３］記載の蒸留装置。
［１５］
前記凝縮器の出口の高さ位置が、前記蒸留塔の最上端の高さ位置よりも高く形成されている、上記［１３］又は［１４］に記載の蒸留装置。
［１６］
前記凝縮器の出口の高さ位置と前記蒸留塔の最上端高さ位置との距離が１０～１０００ｃｍである、上記［１５］に記載の蒸留装置。
［１７］
前記凝縮器の出口の高さ位置と前記蒸留塔の最上端高さ位置との距離が１０～５００ｃｍである、上記［１５］に記載の蒸留装置。
［１８］
前記凝縮器の出口の高さ位置と前記蒸留塔の最上端高さ位置との距離が１０～３００ｃｍである、上記［１５］に記載の蒸留装置。
［１９］
前記蒸留装置が、前記凝縮器の出口から前記蒸留塔に前記凝縮液を還流するための還流配管を備えており、前記還流配管の最下端の高さ位置が、前記蒸留塔の前記還流配管の接続口の高さ位置よりも低く形成されている、上記［１３］～［１８］のいずれかに記載の蒸留装置。
［２０］
前記還流配管の最下端の高さ位置が、前記蒸留塔の前記還流配管の接続口高さ位置よりも１０ｃｍ以上低い、上記［１９］に記載の蒸留装置。
［２１］
前記還流配管の最下端の高さ位置が、前記蒸留塔の前記還流配管の接続口高さ位置よりも１００ｃｍ以上低い、上記［１９］に記載の蒸留装置。
［２２］
前記蒸留塔の外部に前記凝縮器が設置されている、上記［１３］～［２１］のいずれかに記載の蒸留装置。
That is, the present invention is as follows.
[1]
A method for purifying (meth)acrylonitrile or hydrogen cyanide from a solution containing (meth)acrylonitrile, hydrogen cyanide and water, using a distillation apparatus equipped with a distillation column and a condenser connected to the distillation column, comprising the steps of:
a supply step of supplying a gas generated by heating the solution supplied to the distillation column from the distillation column to the condenser;
a reflux step of refluxing a condensate produced by condensing the gas supplied in the supply step, from an outlet of the condenser to the distillation column;
a reflux piping for refluxing the condensate from an outlet of the condenser to the distillation tower, one end of the reflux piping being connected to the outlet of the condenser, the other end of the reflux piping being connected to an upper portion of the distillation tower, and the outlet of the condenser being located at a lower portion of the condenser, and in the reflux step, the condensate is supplied from the outlet of the condenser to the upper portion of the distillation tower via the reflux piping.
A method for purifying (meth)acrylonitrile or hydrogen cyanide.
[2]
the distillation apparatus includes a supply pipe for supplying the gas from the distillation column to the condenser, one end of the supply pipe being connected to a top of the distillation column and the other end of the supply pipe being connected to an upper portion of the condenser;
The purification method according to the above-mentioned [1], wherein in the supplying step, the gas is supplied from the top of the distillation column to an upper part of the condenser via the supply piping.
[3]
The purification method according to the above-mentioned [1] or [2], wherein the height position of the outlet of the condenser of the distillation apparatus is formed higher than the height position of the uppermost end of the distillation column.
[4]
The purification method according to the above-mentioned [3], wherein the distance between the height position of the outlet of the condenser and the height position of the top end of the distillation column is 10 to 1000 cm.
[5]
The purification method according to the above-mentioned [3], wherein the distance between the height position of the outlet of the condenser and the height position of the top end of the distillation column is 10 to 500 cm.
[6]
The purification method according to the above-mentioned [3], wherein the distance between the height position of the outlet of the condenser and the height position of the top end of the distillation column is 10 to 300 cm.
[7]
the distillation apparatus is provided with a reflux pipe for refluxing the condensate from an outlet of the condenser to the distillation column, and a height position of a lowest end of the reflux pipe is formed lower than a height position of a connection port of the reflux pipe of the distillation column;
The purification method according to any one of the above-mentioned [1] to [6], wherein in the reflux step, the condensate is supplied to the distillation column from the outlet of the condenser via the reflux piping.
[8]
The purification method according to the above-mentioned [7], wherein the height position of the lowest end of the reflux piping is 10 cm or more lower than the height position of the connection port of the reflux piping of the distillation column.
[9]
The purification method according to the above-mentioned [7], wherein the height position of the lowest end of the reflux piping is 100 cm or more lower than the height position of the connection port of the reflux piping of the distillation column.
[10]
The purification method according to any one of the above [1] to [9], wherein the condenser is installed outside the distillation column.
[11]
A method for producing (meth)acrylonitrile by ammoxidation of a raw material gas, ammonia and oxygen in the presence of a catalyst, comprising the steps of:
The process includes a purification step of purifying (meth)acrylonitrile or hydrogen cyanide from a solution containing (meth)acrylonitrile, hydrogen cyanide, and water,
A method for producing (meth)acrylonitrile or hydrogen cyanide, wherein the purification step uses the purification method according to any one of [1] to [10] above.
[12]
The method for producing (meth)acrylonitrile or hydrogen cyanide according to the above [11], wherein the raw material gas is at least one selected from the group consisting of propane, propylene, isobutylene, and tertiary butyl alcohol.
[13]
A distillation apparatus for purifying (meth)acrylonitrile or hydrogen cyanide from a solution containing (meth)acrylonitrile, hydrogen cyanide and water, comprising: a distillation column and a condenser connected to the distillation column,
a reflux piping for refluxing a condensate from an outlet of the condenser to the distillation tower, one end of the reflux piping being connected to the outlet of the condenser, the other end of the reflux piping being connected to an upper portion of the distillation tower, and the outlet of the condenser being located at a lower portion of the condenser.
[14]
The distillation apparatus according to [13], further comprising a supply pipe for supplying a gas from the distillation column to the condenser, one end of the supply pipe being connected to a top of the distillation column and the other end of the supply pipe being connected to an upper portion of the condenser.
[15]
The distillation apparatus according to the above [13] or [14], wherein the height position of the outlet of the condenser is formed higher than the height position of the uppermost end of the distillation column.
[16]
The distillation apparatus according to the above-mentioned [15], wherein the distance between the height position of the outlet of the condenser and the height position of the top end of the distillation column is 10 to 1000 cm.
[17]
The distillation apparatus according to the above-mentioned [15], wherein the distance between the height position of the outlet of the condenser and the height position of the top end of the distillation column is 10 to 500 cm.
[18]
The distillation apparatus according to the above-mentioned [15], wherein the distance between the height position of the outlet of the condenser and the height position of the top end of the distillation column is 10 to 300 cm.
[19]
The distillation apparatus according to any one of the above [13] to [18], further comprising a reflux pipe for refluxing the condensate from an outlet of the condenser to the distillation column, and a height position of a lowest end of the reflux pipe is formed lower than a height position of a connection port of the reflux pipe of the distillation column.
[20]
The distillation apparatus according to the above-mentioned [19], wherein the height position of the lowest end of the reflux piping is 10 cm or more lower than the height position of the connection port of the reflux piping of the distillation column.
[21]
The distillation apparatus according to the above-mentioned [19], wherein the height position of the lowest end of the reflux piping is 100 cm or more lower than the height position of the connection port of the reflux piping of the distillation column.
[22]
The distillation apparatus according to any one of the above [13] to [21], wherein the condenser is installed outside the distillation column.
本発明の蒸留装置及び精製方法によれば、（メタ）アクリロニトリル又はシアン化水素の精製工程において、ポンプ等を用いなくても、効率よく還流可能であり、シアン化水素が漏洩を抑制したり、脱青酸脱水塔のトレイの汚れによる閉塞を抑制したりすることにより長期間安定に運転できる。 The distillation apparatus and purification method of the present invention enable efficient reflux in the purification process of (meth)acrylonitrile or hydrogen cyanide without using pumps, etc., and allows for stable operation for a long period of time by suppressing hydrogen cyanide leakage and clogging of the trays of the hydrogen cyanide removal dehydration tower due to contamination.
以下、図面を参照しつつ本発明の実施形態（以下、「本実施形態」という。）について詳細に説明する。本発明は、以下の記載に限定されるものではなく、その要旨の範囲内で種々変形して実施できる。また、図面中、同一要素には同一符号を付すこととし、重複する説明は省略する。また、上下左右等の位置関係は、特に断らない限り、図面に示す位置関係に基づくものとする。更に、図面の寸法比率は、図示の比率に限定されるものではない。 The following describes in detail an embodiment of the present invention (hereinafter referred to as "the present embodiment") with reference to the drawings. The present invention is not limited to the following description, and can be implemented in various modifications within the scope of its gist. In addition, in the drawings, the same elements are given the same reference numerals, and duplicated explanations will be omitted. Furthermore, unless otherwise specified, positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings. Furthermore, the dimensional ratios of the drawings are not limited to the ratios shown in the drawings.
［（メタ）アクリロニトリル又はシアン化水素の精製方法］
本実施形態の（メタ）アクリロニトリル又はシアン化水素の精製方法は、蒸留塔と、該蒸留塔と連結した凝縮器とを備えた蒸留装置を用いて、（メタ）アクリロニトリル、シアン化水素及び水を含む溶液（以下、「（メタ）アクリロニトリル含有溶液」ともいう。）から（メタ）アクリロニトリル又はシアン化水素を精製する精製方法であって、前記蒸留塔に供給された前記溶液を加熱することにより生成したガス（以下、「ガス」ともいう。）を、前記蒸留塔から、前記凝縮器に供給する供給工程と、該供給工程により供給されたガスを凝縮させることにより生成した凝縮液を、前記凝縮器の出口から、前記蒸留塔に還流する還流工程とを含む。
精製方法は、前記凝縮器の出口から前記蒸留塔に前記凝縮液を還流するための還流配管を備えており、前記還流配管の一端が、前記凝縮器の出口と接続しており、前記還流配管の他端が、前記蒸留塔の上部と接続しており、前記凝縮器の出口が、前記凝縮器の下部に位置しており、前記還流工程において、前記還流配管を介して前記凝縮液を前記凝縮器の出口から前記蒸留塔の上部に供給する。
通常、還流工程において、凝縮液を蒸留塔に効率よく還流させるためにポンプ（例えば、キャンドポンプ等）を用いる必要があるが、この場合、シアン化水素が外部に漏洩する虞がある。また、ポンプ内のデッド部においてシアン化水素が重合して閉塞することも考えられるため内部を水でパージする必要がある。しかしながら、水でパージした場合、蒸留塔内でシアン化水素のイオン化が促進され、塔内汚れにより運転継続不能となる虞がある。これに対し、本実施形態の精製方法では、還流配管の一端を凝縮器の下部に位置するように接続し、還流配管の他端を蒸留塔の上部に位置するように接続して、還流配管を介して凝縮液を凝縮器の出口から蒸留塔の上部に供給する。
これにより、位置エネルギーを利用して、ポンプ等を用いなくても、上記凝縮液を凝縮の出口から蒸留塔に効率よく還流できる。このため、シアン化水素が外部に漏洩したり、シアン化水素の重合促進により、蒸留塔内でトレイが閉塞したりすることがなく、蒸留塔を長期的に安定に運転できる。
[Method for purifying (meth)acrylonitrile or hydrogen cyanide]
The method for purifying (meth)acrylonitrile or hydrogen cyanide of the present embodiment is a method for purifying (meth)acrylonitrile or hydrogen cyanide from a solution containing (meth)acrylonitrile, hydrogen cyanide and water (hereinafter also referred to as a "(meth)acrylonitrile-containing solution") using a distillation apparatus equipped with a distillation tower and a condenser connected to the distillation tower, and includes a supply step of supplying a gas (hereinafter also referred to as a "gas") generated by heating the solution supplied to the distillation tower from the distillation tower to the condenser, and a reflux step of refluxing a condensate generated by condensing the gas supplied in the supply step from an outlet of the condenser to the distillation tower.
The purification method includes a reflux piping for refluxing the condensate from an outlet of the condenser to the distillation tower, one end of the reflux piping is connected to the outlet of the condenser and the other end of the reflux piping is connected to an upper part of the distillation tower, and the outlet of the condenser is located at a lower part of the condenser, and in the reflux step, the condensate is supplied from the outlet of the condenser to the upper part of the distillation tower via the reflux piping.
Usually, in the reflux step, a pump (e.g., a canned pump, etc.) must be used to efficiently reflux the condensate to the distillation column, but in this case, there is a risk of hydrogen cyanide leaking to the outside. In addition, hydrogen cyanide may polymerize and clog the dead parts of the pump, so the inside must be purged with water. However, when purging with water, ionization of hydrogen cyanide is promoted in the distillation column, and there is a risk that the operation cannot be continued due to the fouling of the inside of the column. In contrast, in the purification method of this embodiment, one end of the reflux pipe is connected to be located at the bottom of the condenser, and the other end of the reflux pipe is connected to be located at the top of the distillation column, and the condensate is supplied from the outlet of the condenser to the top of the distillation column through the reflux pipe.
This allows the condensate to be efficiently refluxed from the condensation outlet to the distillation column by utilizing potential energy without using a pump, etc. This prevents hydrogen cyanide from leaking to the outside and prevents trays from clogging in the distillation column due to promotion of polymerization of hydrogen cyanide, allowing the distillation column to be operated stably for a long period of time.
［蒸留装置］
以下、本実施形態の精製方法に用いられる蒸留装置について図１を用いて説明する。図１に示す蒸留装置１０は、蒸留塔１と、蒸留塔１と連結した凝縮器２と、蒸留塔１から凝縮器２にガスを供給するための供給配管３と、凝縮器２の出口から蒸留塔１に凝縮液を還流するための還流配管４と、凝縮器２内で凝縮しなかったシアン化水素ガスを外部へ排出する排出管５とを備えている。凝縮器２の出口の高さ位置は、蒸留塔１の最上端の高さ位置よりも高く形成されている。供給配管３の一端は、蒸留塔１の塔頂部と接続しており、供給配管３の他端は、凝縮器２の上部と接続している。還流配管４の一端は、凝縮器２の一端は、凝縮器２の出口と接続しており、還流配管４の他端は、蒸留塔１の上部と接続している。還流配管４の最下端の高さ位置は、蒸留塔１の還流配管４の接続口の高さ位置よりも低く形成されている。なお、本明細書において「上部」とは、蒸留塔の最上端から最下端までの高さを１とした場合、０～０．５までの範囲の高さにある部分をいう。
[Distillation Apparatus]
The distillation apparatus used in the purification method of this embodiment will be described below with reference to FIG. 1. The distillation apparatus 10 shown in FIG. 1 includes a distillation column 1, a condenser 2 connected to the distillation column 1, a supply pipe 3 for supplying gas from the distillation column 1 to the condenser 2, a reflux pipe 4 for refluxing the condensed liquid from the outlet of the condenser 2 to the distillation column 1, and an exhaust pipe 5 for discharging hydrogen cyanide gas not condensed in the condenser 2 to the outside. The height position of the outlet of the condenser 2 is formed higher than the height position of the top end of the distillation column 1. One end of the supply pipe 3 is connected to the top of the distillation column 1, and the other end of the supply pipe 3 is connected to the upper part of the condenser 2. One end of the reflux pipe 4 is connected to the outlet of the condenser 2, and the other end of the reflux pipe 4 is connected to the upper part of the distillation column 1. The height position of the lowest end of the reflux pipe 4 is formed lower than the height position of the connection port of the reflux pipe 4 of the distillation column 1. In this specification, the term "upper portion" refers to a portion having a height ranging from 0 to 0.5, where the height from the top to the bottom of the distillation column is taken as 1.
以下、図１に示す蒸留装置１０を用いて、（メタ）アクリロニトリル含有溶液から（メタ）アクリロニトリル又はシアン化水素を精製する精製方法を説明する。 The following describes a purification method for purifying (meth)acrylonitrile or hydrogen cyanide from a (meth)acrylonitrile-containing solution using the distillation apparatus 10 shown in Figure 1.
（供給工程）
供給工程において、蒸留塔１に供給された（メタ）アクリロニトリル含有溶液を加熱することにより生成したガスを、蒸留塔１から凝縮器２に供給する。この工程では、供給配管３を介してガスを蒸留塔１の塔頂部から凝縮器２の上部に供給することが好ましい。
(Supply process)
In the supply step, a gas generated by heating the (meth)acrylonitrile-containing solution supplied to the distillation column 1 is supplied from the distillation column 1 to the condenser 2. In this step, it is preferable to supply the gas from the top of the distillation column 1 to the upper part of the condenser 2 via the supply pipe 3.
（還流工程）
還流工程において、供給工程により供給されたガスを凝縮させることにより生成した凝縮液を、凝縮器２の出口から、蒸留塔１に還流する。この工程では、還流配管４を介して凝縮液を凝縮器２の出口から蒸留塔１の上部に供給する。これにより、位置エネルギーを利用して、ポンプ等を用いなくても、上記凝縮液を凝縮の出口から蒸留塔に効率よく還流できる。
(Reflux step)
In the reflux step, the condensate produced by condensing the gas supplied in the supply step is refluxed from the outlet of the condenser 2 to the distillation column 1. In this step, the condensate is supplied from the outlet of the condenser 2 to the upper part of the distillation column 1 via the reflux piping 4. This allows the condensate to be efficiently refluxed from the condenser outlet to the distillation column by utilizing potential energy without using a pump or the like.
ここで、還流配管４の最下端の高さ位置が蒸留塔１の還流配管４の接続口の高さ位置よりも低く形成されている。これにより、還流工程において、還流配管４内が凝縮液で満たされ、蒸留塔１内のガスの逆流を一層防止できる傾向にある。 The height position of the bottom end of the reflux pipe 4 is set lower than the height position of the connection port of the reflux pipe 4 of the distillation tower 1. As a result, during the reflux process, the inside of the reflux pipe 4 is filled with condensate, which tends to further prevent backflow of gas in the distillation tower 1.
請求項８及び９
上記最下端の高さ位置と、還流配管４の接続口の高さ位置との距離は、１０ｃｍ以上低いことが好ましく、１００ｃｍ以上低いことがより好ましい。これにより、凝縮液の逆流を一層防止できる傾向にある。
Claims 8 and 9
The distance between the height position of the lowermost end and the height position of the connection port of the reflux pipe 4 is preferably 10 cm or more lower, and more preferably 100 cm or more lower. This tends to further prevent the backflow of the condensate.
蒸留塔１内の圧力と凝縮器２内の圧力との差（圧力差）は、０．０１０～０．０１５ｋｇｆ／ｃｍ2であることが好ましい。これにより、凝縮液の逆流を一層防止できる傾向にある。 The difference between the pressure inside the distillation column 1 and the pressure inside the condenser 2 (pressure difference) is preferably 0.010 to 0.015 kgf/cm 2. This tends to further prevent backflow of the condensed liquid.
精製工程は、更に凝縮器２内で凝縮しなかったシアン化水素ガスを、排出管５を介して外部へ排出する工程を含んでもよい。 The purification process may further include a step of discharging the hydrogen cyanide gas that is not condensed in the condenser 2 to the outside via the exhaust pipe 5.
この工程では、凝縮しなかったシアン化水素、又は凝縮したシアン化水素の一部を外部へ排出してもよい。この工程において、排出されるシアン化水素は、液状の形態であってもよく、蒸気（ガス）の形態であってもよい。排出されるシアン化水素は、例えばナトリウム塩やカリウム塩などで製品化されてもよく、あるいは別の工程の原料として用いられてもよい。上記シアン化水素を別の工程の原料として用いる場合、例えば、上記シアン化水素は、アセトンと反応させ、メタクリル酸メチルの原料として用いられる。 In this process, the hydrogen cyanide that has not been condensed or a portion of the condensed hydrogen cyanide may be discharged to the outside. In this process, the hydrogen cyanide discharged may be in the form of a liquid or in the form of vapor (gas). The hydrogen cyanide discharged may be commercialized as, for example, a sodium salt or potassium salt, or may be used as a raw material in another process. When the hydrogen cyanide is used as a raw material in another process, for example, the hydrogen cyanide is reacted with acetone and used as a raw material for methyl methacrylate.
精製工程は、蒸留塔１でのアクリロニトリル及び青酸の重合を防止するために、ハイドロキノン及び酸（例えば、酢酸、硫酸、リン酸及びグリコール酸）の少なくとも一方を蒸留塔１の塔液中に添加する工程を含んでもよい。この工程では、例えば、ハイドロキノンを水溶液の形態で蒸留塔１の塔頂から供給してもよい。ハイドロキノンの蒸留塔１の塔底液中の濃度は、例えば、１００～６００質量ｐｐｍ程度であってもよい。また、この工程では、例えば、酸を供給配管３へ供給してもよい。酸の蒸留塔１の塔底液中の濃度は、例えば、１０００～３０００質量ｐｐｍ程度であってもよい。 The purification step may include a step of adding at least one of hydroquinone and an acid (e.g., acetic acid, sulfuric acid, phosphoric acid, and glycolic acid) to the liquid in the distillation column 1 in order to prevent polymerization of acrylonitrile and hydrocyanic acid in the distillation column 1. In this step, for example, hydroquinone may be supplied from the top of the distillation column 1 in the form of an aqueous solution. The concentration of hydroquinone in the liquid at the bottom of the distillation column 1 may be, for example, about 100 to 600 ppm by mass. In this step, for example, an acid may be supplied to the supply pipe 3. The concentration of acid in the liquid at the bottom of the distillation column 1 may be, for example, about 1000 to 3000 ppm by mass.
なお、本実施形態の精製方法で用いられる蒸留装置は、必ずしも図１に示す蒸留装置１０に限定されず、蒸留塔と、蒸留塔と連結した凝縮器とを備え、前記凝縮器の出口から前記蒸留塔に凝縮液を還流するための還流配管を備えており、前記還流配管の一端が、前記凝縮器の出口と接続しており、前記還流配管の他端が、前記蒸留塔の上部と接続しており、前記凝縮器の出口が、前記凝縮器の下部に位置していればよい。
蒸留装置は、凝縮器の出口の高さ位置が蒸留塔の最上端高さ位置よりも高く形成されることが好ましい。
これにより、位置エネルギーを利用して、ポンプ等を用いなくても、上記凝縮液を凝縮の出口から蒸留塔に効率よく還流できる。
The distillation apparatus used in the purification method of the present embodiment is not necessarily limited to the distillation apparatus 10 shown in FIG. 1, and may be any apparatus as long as it includes a distillation column, a condenser connected to the distillation column, and a reflux piping for refluxing a condensate from an outlet of the condenser to the distillation column, one end of the reflux piping is connected to the outlet of the condenser, the other end of the reflux piping is connected to an upper portion of the distillation column, and the outlet of the condenser is located in a lower portion of the condenser.
The distillation apparatus is preferably formed such that the outlet of the condenser is located higher than the uppermost end of the distillation column.
This makes it possible to efficiently reflux the condensate from the condensation outlet to the distillation column by utilizing potential energy without using a pump or the like.
※請求項４～６
凝縮器の出口の高さ位置と、蒸留塔の最上端の高さ位置との距離は、好ましくは１０ｃｍ～１０００ｃｍあり、より好ましくは１０ｃｍ～５００ｃｍ、更に好ましくは１０ｃｍ～３００ｃｍである。
これにより、凝縮器下部に凝縮液が溜まることを抑制でき、シアン化水素を含むガスを抜き出す配管にミストが多量に流入するのを防止できる傾向にある。
* Claims 4 to 6
The distance between the height position of the outlet of the condenser and the height position of the uppermost end of the distillation column is preferably 10 cm to 1000 cm, more preferably 10 cm to 500 cm, and even more preferably 10 cm to 300 cm.
This makes it possible to suppress accumulation of condensed liquid at the bottom of the condenser, and tends to prevent a large amount of mist from flowing into the pipe for extracting the gas containing hydrogen cyanide.
蒸留装置に付属する凝縮器は、竪型多管式の熱交換器であることが好ましい。これにより、汚れ防止用の酸を添加することによる効果が一層高まる傾向にある。 The condenser attached to the distillation apparatus is preferably a vertical multi-tube heat exchanger. This tends to further enhance the effect of adding an acid to prevent fouling.
※請求項１０
蒸留装置は、凝縮器を蒸留塔の外部に設置し、上記熱交換器を含むことが好ましい。これにより、ＪＥＴクリーニングが一層容易になる傾向にある。
*Claim 10
It is preferable that the distillation apparatus includes the above-mentioned heat exchanger and a condenser installed outside the distillation column, which tends to make JET cleaning easier.
蒸留装置は、流量計を含まないことが好ましい。これにより、還流ラインでの圧力損失を一層低減でき、シアン化水素の漏洩を一層抑制できる傾向にある。 It is preferable that the distillation apparatus does not include a flow meter. This tends to further reduce pressure loss in the reflux line and further suppress hydrogen cyanide leakage.
［（メタ）アクリロニトリルの製造方法］
本実施形態の（メタ）アクリロニトリルの製造方法は、原料ガス、アンモニア及び酸素を触媒の存在下でアンモ酸化反応させることにより（メタ）アクリロニトリルを製造する方法であって、（メタ）アクリロニトリル、シアン化水素及び水を含む溶液から（メタ）アクリロニトリル又はシアン化水素を精製する精製工程を含み、前記精製工程が、本実施形態の精製方法を用いる。
[Production method of (meth)acrylonitrile]
The method for producing (meth)acrylonitrile of the present embodiment is a method for producing (meth)acrylonitrile by ammoxidation reaction of a raw material gas, ammonia and oxygen in the presence of a catalyst, and includes a purification step of purifying (meth)acrylonitrile or hydrogen cyanide from a solution containing (meth)acrylonitrile, hydrogen cyanide and water, and the purification step uses the purification method of the present embodiment.
（原料ガス）
原料ガスとしては、特に限定されないが、プロパン、プロピレン、イソブチレン、及びターシャリーブチルアルコールからなる群から選択される１種以上であることが好ましい。
(raw gas)
The raw material gas is not particularly limited, but is preferably at least one selected from the group consisting of propane, propylene, isobutylene, and tertiary butyl alcohol.
以下に実施例を挙げて本実施形態を詳細に説明するが、本実施形態は下記実施例に限定されない。 The present embodiment will be described in detail below with reference to examples, but the present embodiment is not limited to the following examples.
［実施例１］
蒸留装置として図１に示す蒸留装置を用いた。プロピレン、アンモニア及び空気を反応させて得られた反応生成物からアセトニトリルを分離することによって得られたアクリロニトリルを８９質量％、アセトニトリル２質量ｐｐｍ、シアン化水素５質量％及び水４質量％を含む液を、５５段の段数を有する棚段塔である蒸留塔の上部第３７段に、流量２２Ｔ／時間で供給した。凝縮器の塔頂部にて１時間当たり１２００Ｍｃａｌの熱を除去し、蒸留塔から凝縮器の塔頂部へ供給配管を介して排出されるガスを凝縮させ、ガスを凝縮させることにより生成した凝縮液を、凝縮器から蒸留塔へ、重力を利用して還流配管を介して還流させた。また、凝縮しない８５質量％以上のシアン化水素を含むガスを凝縮器側面に接続されたガス配管を介して外部へ排出した。また、供給配管内部の汚れを防止するために供給配管内に酢酸をスプレーにて噴霧供給し、凝縮器全体に行き渡らせ、凝縮器の凝縮液中の酢酸濃度を２，０００質量ｐｐｍとした。この運転条件で１年間運転したが、凝縮器の伝熱効率の低下はなく、還流配管及び塔内の詰まりはなく安定的に運転できた。
還流配管が液で満たされたため、脱青酸脱水塔の塔頂蒸気の還流配管での逆流が抑制され、凝縮しないシアン化水素を含むガスのシアン化水素純度が安定した。
また、凝縮器下部に凝縮液が溜まることがなく、シアン化水素を含むガスを抜き出す配管にミストが多量に流入するのを抑制でき、配管汚れが見られなかった。
[Example 1]
The distillation apparatus shown in FIG. 1 was used as the distillation apparatus. A liquid containing 89% by mass of acrylonitrile, 2 ppm by mass of acetonitrile, 5% by mass of hydrogen cyanide, and 4% by mass of water obtained by separating acetonitrile from a reaction product obtained by reacting propylene, ammonia, and air was supplied to the 37th upper stage of a distillation tower, which is a plate tower having 55 stages, at a flow rate of 22 T/hour. Heat of 1200 Mcal per hour was removed at the top of the condenser, and the gas discharged from the distillation tower to the top of the condenser through the supply pipe was condensed, and the condensed liquid generated by condensing the gas was refluxed from the condenser to the distillation tower through the reflux pipe by gravity. In addition, the gas containing 85% by mass or more of hydrogen cyanide that was not condensed was discharged to the outside through a gas pipe connected to the side of the condenser. In addition, in order to prevent dirt from forming inside the supply pipe, acetic acid was sprayed and supplied into the supply pipe by a spray, and spread throughout the entire condenser, so that the acetic acid concentration in the condensed liquid of the condenser was set to 2,000 ppm by mass. The reactor was operated under these operating conditions for one year, and stable operation was possible without any decrease in the heat transfer efficiency of the condenser or clogging in the reflux piping or the tower.
Because the reflux piping was filled with liquid, the backflow of the overhead vapor from the hydrogen cyanide removal tower in the reflux piping was suppressed, and the purity of the hydrogen cyanide in the gas containing uncondensed hydrogen cyanide was stabilized.
In addition, condensed liquid did not accumulate at the bottom of the condenser, and the inflow of a large amount of mist into the piping for extracting the hydrogen cyanide-containing gas was suppressed, and no piping fouling was observed.
［実施例２］
凝縮器から脱青酸脱水塔へ凝縮液を還流させるための還流配管を分岐させ、別工程へ精製されたシアン化水素液を送液したこと以外は実施例１と同様の条件でアクリロニトリルの製造を1年間継続した結果、実施例１と同じく凝縮器の伝熱効率の低下はなく、還流配管及び塔内の詰まりはなく安定的に運転できた。
[Example 2]
The production of acrylonitrile was continued for one year under the same conditions as in Example 1, except that a reflux pipe for refluxing the condensate from the condenser to the hydrogen cyanide-removing dehydration tower was branched and the purified hydrogen cyanide liquid was sent to a separate process. As a result, as in Example 1, there was no decrease in the heat transfer efficiency of the condenser, and no clogging occurred in the reflux pipe or in the tower, and stable operation was possible.
［実施例３］
凝縮器から脱青酸脱水塔へ凝縮液を還流させるための還流配管の最下端の高さ位置が、脱青酸脱水塔と還流配管との接続口の高さ位置と同じとしたこと以外は実施例１と同様の条件でアクリロニトリルの製造を1年間継続した結果、実施例１と同じく凝縮器の伝熱効率の低下はなく、還流配管及び塔内の詰まりはなく運転できた。
[Example 3]
The production of acrylonitrile was continued for one year under the same conditions as in Example 1, except that the height position of the lowest end of the reflux piping for refluxing the condensate from the condenser to the hydrogen cyanide-removing dehydrating tower was set to be the same as the height position of the connection port between the hydrogen cyanide-removing dehydrating tower and the reflux piping. As a result, as in Example 1, there was no decrease in the heat transfer efficiency of the condenser, and the operation was possible without clogging of the reflux piping and the tower.
［実施例４］
凝縮器から脱青酸脱水塔へ凝縮液を還流させるための還流配管の最下端の高さ位置が、脱青酸脱水塔と還流配管との接続口の高さ位置と同じとし、凝縮器出口の高さの位置を脱青酸脱水塔塔頂の高さ位置よりも低くしたこと以外は実施例１と同様の条件でアクリロニトリルの製造を1年間継続した結果、実施例１と同じく凝縮器の伝熱効率の低下はなく、還流配管及び塔内の詰まりはなく運転できた。
[Example 4]
The production of acrylonitrile was continued for one year under the same conditions as in Example 1, except that the height position of the lowest end of the reflux piping for refluxing the condensate from the condenser to the hydrogen cyanide-removing dehydrating tower was the same as the height position of the connection port between the hydrogen cyanide-removing dehydrating tower and the reflux piping, and the height position of the condenser outlet was lower than the height position of the top of the hydrogen cyanide-removing dehydrating tower. As a result, as in Example 1, there was no decrease in the heat transfer efficiency of the condenser, and the operation was possible without clogging of the reflux piping and the inside of the tower.
［比較例１］
図１に示す蒸留装置を用いず、通常用いられる蒸留装置を用い、凝縮器でガスを凝縮させることにより生成した凝縮液を、凝縮器から蒸留塔へ、ポンプを利用して還流させ還流流量を差圧式流量計で測定し、ポンプ及び流量計の導圧管内部を水でパージしたこと以外は実施例１と同様の条件で運転した。蒸留塔内でシアン化水素のポリマーが発生したことによりトレイが閉塞し、６ヶ月で運転継続不能となった。
[Comparative Example 1]
An ordinary distillation apparatus was used instead of the distillation apparatus shown in Figure 1, the condensate produced by condensing the gas in the condenser was refluxed from the condenser to the distillation column using a pump, the reflux flow rate was measured with a differential pressure flowmeter, and the inside of the pump and the pressure guiding tube of the flowmeter was purged with water, but other than these, the operation was carried out under the same conditions as in Example 1. Hydrogen cyanide polymer was generated in the distillation column, causing the tray to become clogged, and the operation could not be continued after 6 months.
Claims (20)
前記蒸留塔に供給された前記溶液を加熱することにより生成したガスを、前記蒸留塔から、前記凝縮器に供給する供給工程と、
該供給工程により供給されたガスを凝縮させることにより生成した凝縮液を、前記凝縮器の出口から、前記蒸留塔に還流する還流工程とを含み、
前記凝縮器の出口から前記蒸留塔に前記凝縮液を還流するための還流配管を備えており、前記還流配管の一端が、前記凝縮器の出口と接続しており、前記還流配管の他端が、前記蒸留塔の上部と接続しており、前記凝縮器の出口が、前記凝縮器の下部に位置しており、前記還流工程において、前記還流配管を介して前記凝縮液を前記凝縮器の出口から前記蒸留塔の上部に供給し、前記還流配管がポンプを有さず、前記蒸留装置の前記凝縮器の前記出口の高さ位置が、前記蒸留塔の最上端の高さ位置よりも高く形成されている、
（メタ）アクリロニトリル又はシアン化水素の精製方法。 A method for purifying (meth)acrylonitrile or hydrogen cyanide from a solution containing (meth)acrylonitrile, hydrogen cyanide and water, using a distillation apparatus equipped with a distillation column and a condenser connected to the distillation column, comprising the steps of:
a supply step of supplying a gas generated by heating the solution supplied to the distillation column from the distillation column to the condenser;
a reflux step of refluxing a condensate produced by condensing the gas supplied in the supply step, from an outlet of the condenser to the distillation column;
the distillation apparatus further comprises a reflux piping for refluxing the condensate from an outlet of the condenser to the distillation tower, one end of the reflux piping being connected to the outlet of the condenser and the other end of the reflux piping being connected to an upper portion of the distillation tower, and the outlet of the condenser being located at a lower portion of the condenser; in the reflux step, the condensate is supplied from the outlet of the condenser to the upper portion of the distillation tower via the reflux piping; the reflux piping does not include a pump; and the height position of the outlet of the condenser of the distillation apparatus is formed higher than the height position of the uppermost end of the distillation tower .
A method for purifying (meth)acrylonitrile or hydrogen cyanide.
前記供給工程において、前記供給配管を介して前記ガスを前記蒸留塔の塔頂部から前記凝縮器の上部に供給する、請求項１記載の精製方法。 the distillation apparatus includes a supply pipe for supplying the gas from the distillation column to the condenser, one end of the supply pipe being connected to a top of the distillation column and the other end of the supply pipe being connected to an upper portion of the condenser;
2. The purification method according to claim 1, wherein in the supplying step, the gas is supplied from the top of the distillation column to an upper portion of the condenser via the supply piping.
前記還流工程において、前記還流配管を介して前記凝縮液を前記凝縮器の出口から前記蒸留塔に供給する、請求項１～５のいずれか１項に記載の精製方法。 the distillation apparatus is provided with a reflux pipe for refluxing the condensate from an outlet of the condenser to the distillation column, and a height position of a lowest end of the reflux pipe is formed lower than a height position of a connection port of the reflux pipe of the distillation column;
The purification method according to any one of claims 1 to 5 , wherein in the reflux step, the condensate is supplied to the distillation column from an outlet of the condenser via the reflux piping.
（メタ）アクリロニトリル、シアン化水素及び水を含む溶液から（メタ）アクリロニトリル又はシアン化水素を精製する精製工程を含み、
前記精製工程が、請求項１～９のいずれか１項に記載の精製方法を用いる、（メタ）アクリロニトリル又はシアン化水素の製造方法。 A method for producing (meth)acrylonitrile by ammoxidation of a raw material gas, ammonia and oxygen in the presence of a catalyst, comprising the steps of:
The process includes a purification step of purifying (meth)acrylonitrile or hydrogen cyanide from a solution containing (meth)acrylonitrile, hydrogen cyanide, and water,
A method for producing (meth)acrylonitrile or hydrogen cyanide, wherein the purification step uses the purification method according to any one of claims 1 to 9 .
前記凝縮器の出口から前記蒸留塔に凝縮液を還流するための還流配管を備えており、前記還流配管の一端が、前記凝縮器の出口と接続しており、前記還流配管の他端が、前記蒸留塔の上部と接続しており、前記凝縮器の出口が、前記凝縮器の下部に位置しており、前記還流配管がポンプを有さず、前記凝縮器の前記出口の高さ位置が、前記蒸留塔の最上端の高さ位置よりも高く形成されている、（メタ）アクリロニトリル又はシアン化水素を精製する蒸留装置。 A distillation apparatus for purifying (meth)acrylonitrile or hydrogen cyanide from a solution containing (meth)acrylonitrile, hydrogen cyanide and water, comprising: a distillation column and a condenser connected to the distillation column,
a reflux piping for refluxing a condensate from an outlet of the condenser to the distillation tower, one end of the reflux piping being connected to the outlet of the condenser and the other end of the reflux piping being connected to an upper portion of the distillation tower, the outlet of the condenser being located at a lower portion of the condenser, the reflux piping not including a pump, and a height position of the outlet of the condenser being formed higher than a height position of a top end of the distillation tower .
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2019013292 | 2019-01-29 | ||
| JP2019013292 | 2019-01-29 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2020121969A JP2020121969A (en) | 2020-08-13 |
| JP7513398B2 true JP7513398B2 (en) | 2024-07-09 |
Family
ID=71811585
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2020005954A Active JP7513398B2 (en) | 2019-01-29 | 2020-01-17 | Method for purifying (meth)acrylonitrile and method for producing (meth)acrylonitrile |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP7513398B2 (en) |
| CN (2) | CN212335081U (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012090691A (en) | 2010-10-25 | 2012-05-17 | Kokuyo Co Ltd | Top board connector and connecting structure of desk |
| CN103804230A (en) | 2014-01-29 | 2014-05-21 | 中国石油集团东北炼化工程有限公司吉林设计院 | Method for reducing content of methacrylonitrile in acrylonitrile and acrylonitrile production system |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3907749B2 (en) * | 1996-07-09 | 2007-04-18 | 旭化成ケミカルズ株式会社 | Purification method of acetonitrile |
| US5840955A (en) * | 1997-11-25 | 1998-11-24 | Sockell; Edward J. | Waste minimization and product recovery process |
| CN1195757A (en) * | 1998-02-26 | 1998-10-14 | 李世维 | Back-flow device and water heater |
| JP5605922B2 (en) * | 2010-12-27 | 2014-10-15 | 旭化成ケミカルズ株式会社 | Purification method of acrylonitrile |
| JP5605921B2 (en) * | 2010-12-27 | 2014-10-15 | 旭化成ケミカルズ株式会社 | Purification method of acrylonitrile |
| CN103531832B (en) * | 2013-09-26 | 2017-11-03 | 浙江吉利控股集团有限公司 | Electric automobile and its aluminum air battery system |
| CN103508847B (en) * | 2013-09-30 | 2016-06-08 | 天津大学 | A kind of method of high-purity butanols of butanols dewatering and recovery and device |
| US10294197B2 (en) * | 2016-10-21 | 2019-05-21 | Asahi Kasei Kabushiki Kaisha | Purifying method, production method, and distillation apparatus for acrylonitrile |
-
2020
- 2020-01-17 JP JP2020005954A patent/JP7513398B2/en active Active
- 2020-01-17 CN CN202020105180.0U patent/CN212335081U/en active Active
- 2020-01-17 CN CN202010053054.XA patent/CN111484428A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012090691A (en) | 2010-10-25 | 2012-05-17 | Kokuyo Co Ltd | Top board connector and connecting structure of desk |
| CN103804230A (en) | 2014-01-29 | 2014-05-21 | 中国石油集团东北炼化工程有限公司吉林设计院 | Method for reducing content of methacrylonitrile in acrylonitrile and acrylonitrile production system |
Non-Patent Citations (1)
| Title |
|---|
| 長倉三郎 ほか，岩波 理化学事典 第5版，株式会社 岩波書店，1998年，p.730 |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111484428A (en) | 2020-08-04 |
| JP2020121969A (en) | 2020-08-13 |
| CN212335081U (en) | 2021-01-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100623826B1 (en) | Vertical multi-tubular heat exchanger and distillation tower system | |
| US7393436B2 (en) | Thermal separating process for removing at least one stream containing enriched (meth) acrylic monomers | |
| US8530700B2 (en) | Process for producing acrylic acid | |
| JP4558870B2 (en) | Tower-type processing method and apparatus | |
| KR101426976B1 (en) | Process for transferring heat to a liquid mixture comprising at least one (meth)acrylic monomer | |
| RU2472770C2 (en) | Method of producing alkyl esters of methacrylic acid by azeotropic distillation | |
| CN1267660A (en) | Refining method for (methyl) propenoic acid and/or its ester | |
| KR20190060820A (en) | Quench column after-cooler process | |
| JP6761758B2 (en) | Reduced fouling in the acetonitrile removal step of acrylonitrile recovery | |
| JP7513398B2 (en) | Method for purifying (meth)acrylonitrile and method for producing (meth)acrylonitrile | |
| WO2019142862A1 (en) | Method of producing (meth)acrylic acid or ester thereof | |
| JP5066309B2 (en) | Purification method for substances containing easily polymerizable substances | |
| JP4147015B2 (en) | Gas condensation method | |
| JP5364884B2 (en) | Method for producing (meth) acrylonitrile | |
| JP6391596B2 (en) | Separation of acrolein from process gas of oxidation by heterogeneous catalysis of propene | |
| RU2352379C2 (en) | Reservoir for easily polymerised compound | |
| CN105008327B (en) | Urea equipment remodeling method | |
| RU2350598C2 (en) | Method of (meth)acrylic acid purification | |
| JP4437930B2 (en) | Acrylic acid distillation purification method | |
| CN111566080B (en) | Method for producing (meth) acrylic acid or ester thereof | |
| JP4186459B2 (en) | Tower equipment for easily polymerizable compounds | |
| JP4095471B2 (en) | Distillation method of easily polymerizable substances | |
| JP2005336099A (en) | Method for cooling reactive gas containing (meth)acrylic acid or/and (meth)acrolein | |
| CN102721320B (en) | Anti-clogging method for heat exchanger and anti-clogging heat exchanger for acetonitrile purification | |
| JP5066496B2 (en) | Purification method for substances containing easily polymerizable substances |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20221104 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20230926 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20231003 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20231201 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20240215 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20240614 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20240627 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 7513398 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |