KR102200814B1 - Method for producing conjugated diene - Google Patents

Abstract

The present invention relates to a method and apparatus for producing butadiene.According to the present invention, butane is used as a dilution gas, and even if a refrigerant lower than a cryogenic refrigerant is used, C4 mixtures and gas products excluding butadiene can be easily separated. As a result, there is an effect of providing a manufacturing method and a manufacturing apparatus of butadiene capable of securing high purity butadiene and economical efficiency of the process, such as reducing energy and raw material costs and improving productivity.

Description

Butadiene manufacturing method {METHOD FOR PRODUCING CONJUGATED DIENE}

The present invention relates to a method for producing butadiene, and more particularly, to a method for producing butadiene capable of securing a high-purity butadiene and economical efficiency of a process such as energy and raw material cost reduction and productivity improvement.

Butadiene is used as an intermediate of many petrochemical products in the petrochemical market, and its demand and value are gradually increasing as one of the most important basic oils in the petrochemical market.

Methods of producing butadiene include extraction from C4 fraction through naphtha cracking, direct dehydrogenation of butene, and oxidative dehydrogenation of butene.

Among them, the method of producing butadiene through oxidative dehydrogenation of butene uses oxygen as a reactant to remove two hydrogens from butene to produce butadiene.Since stable water is produced as a product, it is very thermodynamically It is advantageous, and since it is an exothermic reaction unlike the direct dehydrogenation reaction, a high yield of butadiene can be obtained even at a lower reaction temperature than the direct dehydrogenation reaction. Therefore, a method for producing butadiene through oxidative dehydrogenation of butene can be an effective production process capable of meeting increasing demand for butadiene.

On the other hand, the oxidative dehydrogenation method of butene as described above reduces the risk of explosion due to oxygen and mainly uses nitrogen, steam, etc. as a dilution gas in addition to raw materials to remove the heat of reaction. Among the methods of absorbing hydrocarbons in the reaction product using a solvent when separating hydrocarbons from reaction products containing gases (COx, O _2, etc.) and hydrocarbons, and cooling the reaction products to liquefy hydrocarbons. Mainly, the absorption method is being used. This is because the method of liquefying and separating the reaction product requires a cryogenic refrigerant during liquefaction due to the dilution gas and light gas flows present in the reaction product, which increases the equipment cost and operation cost, making it difficult to secure the economics of the process. Because

In this regard, FIG. 1 is a view for explaining a conventional apparatus and method for producing butadiene.

Referring to FIG. 1, butadiene obtained from the oxidation dehydrogenation reaction by passing a reaction raw material including butene, oxygen (O ₂ ), steam and dilute gas (N ₂ ) through an oxidation dehydrogenation reaction unit 110 A cooling separation unit 120 for separating water from the C4 mixture and gas product containing; An absorption and separation unit 130 for separating butadiene or a C4 mixture including butadiene and hydrocarbons from the oxidation dehydrogenation product from which water is separated; And a purification unit 140 for separating butadiene from a stream containing butadiene separated by the absorption and separation unit 130; and, in the absorption and separation unit 130, all or selectively absorbing hydrocarbons By using a solvent capable of selective absorption or total absorption of the hydrocarbons excluding COx, O ₂ , some n-butane and N ₂ used as a diluent gas.

The oxidative dehydrogenation reaction unit 110 converts butene, oxygen (O ₂ ), steam, diluted gas (N ₂ ), and a gas containing unreacted butenes recovered from the purification unit into a ferritic reaction material. It may be driven under isothermal or adiabatic conditions using a catalyst or a bismuth molybdate-based catalyst.

The cooling separation unit 120 may be driven by a direct cooling method (quencher) of rapid cooling or an indirect cooling method.

1 is an example in which only butadiene is selectively absorbed and separated by the absorption and separation unit 130, but the absorption and separation unit 130 selectively absorbs only butadiene from the reaction product from which water is removed, or the entire hydrocarbons including a C4 mixture. It may be driven by an absorption method using an absorbable solvent. The selective absorption solvent may be one or more selected from the group consisting of ACN (Acetonitrile), NMP (N-methylpyrrolidone), and DMF (Dimethyl formamide). As the total absorption solvent, for example, toluene, xylene, or a mixture thereof may be used.

The COx, O ₂ , and N ₂ used as the dilution gas separated by the absorption and separation unit 130 are completely incinerated, or in some cases, some are recovered and reused in the reaction unit, and some are incinerated.

The purification unit 140 may be a conventional butadiene purification apparatus, for example, an ACN (Acetonitrile) process, a phase NMP (N-methylpyrrolidone) process, or a DMF (dimethyl formamide) process, and a part of the process is modified as needed. Butadiene can be purified by being driven in a form.

However, in order to absorb a hydrocarbon from a hydrocarbon mixture including gases such as N ₂ and COx and O ₂ used as a diluting gas in the absorption separation process 130, a large amount of solvent is required because the partial pressure of the hydrocarbon is low, A large amount of energy is used in the process of recovering this and in the process of recovering and purifying butadiene in the purification unit 140. In addition, even if the absorption separation process is replaced with a condensation process, a cryogenic refrigerant is required, and the economic feasibility of the process such as raw material cost and productivity cannot be secured.

Korean Patent Application Publication No. 2012-0103759

In order to solve the problems of the prior art as described above, the present invention uses butane instead of nitrogen as a diluent gas when preparing butadiene through oxidative dehydrogenation of butene, and an absorption method used to separate butadiene from reaction products when using nitrogen. Instead, it adopts a condensation method in which butadiene is liquefied and separated using a low-temperature refrigerant or cooling water. In particular, in order to minimize the loss of the target product (referring to butadiene) discharged along with the discharge stream containing COx, O ₂ , and n-butane separated from the condensation process, active ingredients (all including butadiene) from the upper stream of the condensation process It is an object of the present invention to provide a method for producing butadiene that can secure economic feasibility of a process such as energy and raw material cost reduction and productivity improvement by selectively recovering the target product among hydrocarbons).

All of the above and other objects of the present invention can be achieved by the present invention described below.

In order to achieve the above object, the present invention

Passing a reaction raw material containing butene, oxygen (O ₂ ), steam, and a diluted gas through an oxidation dehydrogenation reaction unit to generate an oxidative dehydrogenation reaction product including butadiene, and

Separating water while passing the oxidative dehydrogenation reaction product including butadiene through a cooling separation unit,

Condensing hydrocarbons while passing the oxidative dehydrogenation reaction product from which the water is separated through a condensation separator,

Separating COx and O ₂ while passing an oxidative dehydrogenation reaction product including hydrocarbons not condensed in the condensation separation unit through an absorption separation unit,

The n-butane condensed in the condensation and separating unit, the crude hydrocarbon containing butene and butadiene, is passed through the purification unit to separate butadiene or pass through the degassing unit to further separate COx and O ₂ and then n-butane and butene. And separating butadiene while passing the crude hydrocarbon containing and butadiene through the purification unit,

Gas containing n-butane excluding butadiene separated in the purification unit is re-introduced into the oxidation dehydrogenation reaction unit,

The butadiene is separated from the purification unit and the discharge stream containing the remaining butene is mixed with raw material butene and introduced into the oxidation dehydrogenation reaction unit, and the dilution gas is butane.It provides a method for producing butadiene.

In addition, the present invention is an oxidative dehydrogenation reaction unit for obtaining an oxidative dehydrogenation reaction product including butadiene by oxidative dehydrogenation of a reaction raw material including butene, oxygen (O ₂ ), steam and dilute gas;

A cooling separation unit for separating water from an oxidative dehydrogenation reaction product including butadiene obtained from the oxidative dehydrogenation reaction;

A condensation separator for condensing hydrocarbons from the oxidative dehydrogenation reaction product from which water is separated;

An absorption separation unit for separating COx and O ₂ from an oxidation dehydrogenation reaction product including hydrocarbons not condensed in the condensation separation unit; And

Including; a purification unit for separating butadiene from the crude hydrocarbon containing n-butane, butene and butadiene condensed in the condensation separation unit,

Gas containing n-butane excluding butadiene separated in the purification unit is re-introduced into the oxidation dehydrogenation reaction unit,

The butadiene is separated from the purification unit and the discharge stream containing the remaining butene is mixed with fresh butene and introduced into the oxidative dehydrogenation reaction unit, and the dilution gas is butane.It provides an apparatus for producing butadiene.

According to the present invention, butane is used instead of nitrogen as a diluting gas when producing butadiene through oxidative dehydrogenation of butene, and butadiene is liquefied using a low temperature refrigerant or cooling water instead of the absorption method used to separate butadiene from the reaction product when using nitrogen. The process by minimizing the loss of butadiene through the condensation separation method to separate it and the absorption separation method in which the target product (butadiene) is selectively absorbed and recovered from the hydrocarbons flowing to the upper stream after condensation separation, thereby minimizing the loss of raw materials, energy and production costs It is an object of the present invention to provide a method for producing butadiene that can secure high-purity butadiene.

1 is a view for explaining a conventional butadiene manufacturing apparatus and method.
2 to 6 are views for explaining the butadiene manufacturing apparatus and manufacturing method according to the present invention.

Hereinafter, the method and apparatus for producing butadiene of the present invention will be described in detail. The method and apparatus for producing butadiene of the present invention are characterized by applying a condensation separation process using butane as a diluted gas and an absorption separation process that selectively absorbs and recovers hydrocarbons in the discharge stream flowing out through the upper part of the condensation separation process. to be. In this way, if butane is used as a dilution gas, the condensation separation unit can easily separate hydrocarbons from the oxidative dehydrogenation reaction product even with a low temperature refrigerant or cooling water, and the absorption separation unit selects the target product from the hydrocarbons that flow out to the outside. It is possible to economically manufacture butadiene by minimizing butadiene that is recovered by absorption and leaked out of the system.

Hereinafter, a method and apparatus for manufacturing butadiene according to the present invention will be described in more detail with reference to the drawings. 2 to 6 are diagrams for explaining an apparatus and method for producing butadiene according to the present invention.

Referring to FIG. 2, first, a reaction raw material including butene, oxygen (O ₂ ), steam, and a diluted gas (butane) is passed through an oxidation dehydrogenation reaction unit 210 to obtain butadiene as an oxidation dehydrogenation reaction product. A mixture of C4 and a gaseous product is generated, and is introduced into the cooling separation unit 220 along the flow B1 discharged from the process. At this time, the reaction raw material merges with the discharge stream (B7) containing n-butane generated after purification in the purification process and flows into the oxidative dehydrogenation reaction unit 210, and is produced after purification in the purification process. Another discharge stream B8 including reactive butenes is introduced into the oxidative dehydrogenation reaction unit 210 by merging with raw material butenes. The flow (B1) discharged from the oxidative dehydrogenation process may contain butadiene, n-butane, butene, O ₂ , CO ₂ , H ₂ O, etc., and water is separated by flowing into the cooling separation unit 220.

The discharge flow (B2) generated after the cooling separation may contain butadiene, n-butane, butene, O ₂ , CO _2, etc., and flows into the condensation separation unit 230.

The discharge flow (B3) generated after the condensation separation includes an oxidative dehydrogenation reaction product including uncondensed hydrocarbons after condensing hydrocarbons through compression/cooling using cooling water or low-temperature refrigerant in the condensation separation process. In the other discharge stream (B4) generated after the condensation separation may contain n-butane condensed in the condensation separation unit 230, crude hydrocarbons including butene and butadiene, and in the purification unit 240 Butadiene can be purified.

The discharge flow (B5) generated in the absorption separation process may include O ₂ , COx, etc. separated by the condensation separation unit 230, and another discharge flow (B6) generated in the absorption separation process includes absorption separation. In the part 250, hydrocarbons including n-butane, butene and butadiene excluding COx and O ₂ may be selectively absorbed in a solvent, and the discharge flow B6 is transferred to the condensation separator 230 Can be reintroduced.

The discharge flow (B4) generated after the condensation separation may pass through the purification unit 240 to separate butadiene, and the discharge flow (B7) generated after the purification may contain abundant residual n-butane, By forming a recycle flow introduced into the oxidative dehydrogenation reaction unit 210, a diluted gas can be supplied to concentrate as much as a required amount, and the butadiene is separated from the purification unit 240 and the discharge flow containing the remaining butene (B8 ) May include a step of being mixed with raw material butene and introduced into the oxidative dehydrogenation reaction unit 210, and in this case, since the reaction can be continuously carried out, the effect of improving productivity is excellent.

The “crude hydrocarbon” refers to a crude hydrocarbon commonly used in this technical field, and unless otherwise specified, a hydrocarbon containing butadiene obtained from an oxidative dehydrogenation reaction product as a raw material for the refining unit Refers to.

The term “COx” refers to CO, CO ₂ unless otherwise specified.

The butene may be 1-butene, 2-butene, or a mixture thereof. The raw material gas containing butene is not particularly limited if it is a raw material gas containing butene that can be used in the production of butadiene.

For example, the butene may be obtained from a high purity butene gas, a hydrocarbon mixture containing butenes, such as raffinate-2 and raffinate-3 among C4 fractions produced by naphtha decomposition.

The steam is a gas that is introduced for the purpose of reducing the risk of explosion of reactants in the oxidation dehydrogenation reaction, preventing coking of the catalyst and removing reaction heat.

Meanwhile, the oxygen (O ₂ ) reacts with butene as an oxidizing agent to cause a dehydrogenation reaction.

The catalyst filled in the reactor is not particularly limited as long as it is capable of producing butadiene by oxidative dehydrogenation of butene, and may be, for example, a ferrite catalyst, a bismuth molybdate catalyst, or an iron catalyst.

In one embodiment of the present invention, the catalyst may be a ferrite catalyst, and among them, zinc ferrite, magnesium ferrite, and manganese ferrite may be used to increase the selectivity of butadiene. The type and amount of the reaction catalyst may vary depending on the specific conditions of the reaction.

The dilution gas may be butane.

The oxidative dehydrogenation reaction unit 210 is, for example, a residue from which butene, oxygen (O ₂ ), steam, and butadiene are separated from the purification unit 240 and is used as the oxidative dehydrogenation reaction unit. It may be driven under isothermal or adiabatic conditions using a ferritic catalyst or an iron catalyst using a gas containing n-butane as a reaction raw material.

For example, oxygen (O ₂ ) included in the reaction raw material may be introduced in the form of a gas of 90% or more, 95% or more, or 98% or more of purity.

The gas form having a purity of 90% or higher may mean that oxygen (O ₂ ) is not introduced from the air, but is introduced in the form of pure oxygen gas, through which the amount of active ingredients contained in the reaction raw material is measured in real time. Thus, the amount of components contained in the reaction raw material introduced into the reactor can be individually controlled, and most of the introduced oxygen can be burned out.

For example, the reaction conditions in the oxidative dehydrogenation reaction unit 210 may be a molar ratio of butene: oxygen: water vapor: dilute gas (n-butane) = 1: 0.5 to 3: 0.05 to 20: 0.05 to 20.

As a specific example, the oxidative dehydrogenation reaction unit 210 includes a molar ratio of oxygen:butene of 0.5-3:1, a molar ratio of water vapor:butene of 0.05-20:1, an n-butane:butene molar ratio of 0.05-20:1, and a reaction pressure of normal pressure. It is preferable to be driven under isothermal or adiabatic conditions of ~10atm, reaction temperature 150~650℃.

The cooling separation unit 220 may be driven by, for example, a direct cooling method of rapid cooling or an indirect cooling method, wherein the rapid cooling temperature is a temperature at which hydrocarbons are not cooled while cooling water, For example, it may be 0 ~ 100 ℃.

The condensation separation unit 230 may be, for example, a single compression structure of 1 stage, a multistage compression structure of 2 to 10 stages, or a multistage compression structure of 1 to 2 stages. The reason for the multi-stage compression is that when compressing from the initial pressure to the target pressure at one time, not only a lot of power is required, but also heat is generated by gas compression, which causes the gas to expand and the compression efficiency decreases. In order to prevent this, multi-stage compression is performed, and the heat generated in the compression process may be cooled using a cooler.

Condensation conditions in the condensation separation unit 230 may be determined to have a range (above the explosion limit or below the limit oxygen concentration) in which the flow is out of the explosion range in consideration of unreacted oxygen.

In one embodiment of the present invention, the refrigerant used in the condensation separation unit 230 is cooling water, ethylene glycol, an ethylene glycol aqueous solution having a concentration of 20 to 100% by weight, propylene glycol, a propylene glycol aqueous solution having a concentration of 30 to 100% by weight, And it may be one or more selected from the group consisting of a propylene-based solvent. The propylene-based solvent is, for example, propylene or a compound containing propylene, and may be a material having a boiling point of -10°C or less, or -10 to -50°C.

The refrigerant may be preferably cooling water, 0 to 40°C cooling water, or 5 to 30°C, and in this case, the extrusion discharge temperature may be 250°C or less, or 50 to 200°C, and the compressed discharge flow The cooling temperature may be 120 °C or less, or 20 to 80 °C.

Conventionally, when nitrogen is used as the dilution gas and the use of a cryogenic refrigerant is required to separate the dilution gas and the light gas stream by the condensation method, in the present invention, a lower grade refrigerant is used by introducing butane as the dilution gas. It became possible.

The purification unit 240 may employ a conventional apparatus for purifying butadiene, and for example, may be constituted by an ACN (Acetonitrile) process, an N-methylpyrrolidone (NMP) process, or a DMF (dimethyl formamide) process. The solvent used in the purification unit 240 may be the same solvent as the solvent used in the absorption and separation unit 250, or other solvents may be used if necessary. The solvent may be separated from the purification unit 240 and circulated to the absorption separation unit 250 (discharge flow not shown).

The absorption separation unit 250 is an absorption method using a solvent such as ACN (Acetonitrile), NMP (N-methylpyrrolidone), or DMF (Dimethyl formamide) capable of selectively absorbing butadiene and butenes among hydrocarbons. Can be driven by When the COx and O ₂ separated by the absorption and separation unit 250 are incinerated, heat generated by incineration may be recycled in the oxidation and dehydrogenation reaction unit 210 or the condensation separation unit 230.

The butadiene obtained through the separation step can be recovered as high purity butadiene by removing the solvent, high boiling point and low boiling point components through the purification step.

In one embodiment of the present invention, the purity of butadiene finally obtained through the series of steps may be 95.0 to 99.9%.

3 shows that the oxidation dehydrogenation reaction product from which water is separated by passing through the cooling separation unit 220 in FIG. 2 is introduced into the purification unit 240 through the condensation separation unit 230 and the absorption separation unit 250 (B4 ) Is a subdivided process including the degassing unit and solvent recovery.

The degassing unit may be driven by stripping or degassing using a conventional column, for example.

Referring to FIG. 3, first, oxidative dehydrogenation containing butadiene obtained by passing a reaction raw material containing butene, oxygen (O ₂ ), steam, and dilute gas (butane) through an oxidation dehydrogenation reaction unit 310 A reaction product is generated, and flows into the cooling separation unit 320 along the flow B1 discharged from the reaction process. At this time, the reaction raw material is purified in the purification process, and the gas containing n-butane generated is introduced into the oxidation dehydrogenation reaction unit 310 along the discharge flow (B7). The reactive butenes merge with the raw material butenes along the discharge flow B8 and flow into the oxidation dehydrogenation reaction unit 310.

The flow B1 discharged from the reaction process may contain butadiene, n-butane, butene, O ₂ , CO ₂ , H ₂ O, etc., and water is separated by flowing into the cooling separation unit 320.

The discharge flow B2 generated after the cooling separation may contain butadiene, n-butane, butene, O ₂ , CO _2, etc., and flow into the condensation separation unit 330.

The discharge flow (B3) generated after the condensation separation includes an oxidative dehydrogenation reaction product including uncondensed hydrocarbons after condensing hydrocarbons through compression/cooling using cooling water or low-temperature refrigerant in the condensation separation process. I can. Another discharge stream (B4') generated after the condensation separation may include condensed n-butane, hydrocarbons including butene and butadiene.

The discharge flow (B11) generated after the degassing includes COx and O ₂ additionally separated from the degassing unit 360, and can be absorbed and separated by inputting to the absorption and separating unit 350, and generated after the degassing. Another discharge stream (B4") may be a crude hydrocarbon excluding COx and O ₂ further separated from the degassing unit 360, and may be injected into the purification unit 340 to purify butadiene.

Said generated in the absorption separation process draw stream (B5), the discharge flow (B3) containing the O _2, COx and so on away from the condensate separation unit 330, and the O _2, COx and so on away from the degassing unit 360 In the included discharge stream (B11), the remaining O ₂ , COx, etc. may be included after selectively absorbing and removing hydrocarbons such as butadiene or butenes contained, and in another discharge stream generated after absorption and separation (B6') In the absorption separation unit 350, a crude hydrocarbon containing n-butane, butene and butadiene, excluding COx and O ₂ , may be absorbed by a solvent.

The discharge flow (B7) generated after separation and purification of butadiene passing through the purification unit 340 may contain an abundant amount of remaining n-butane, and to form a recycle flow that is introduced into the oxidation dehydrogenation reaction unit 310 do.

The solvent is separated in the purification unit 340 and can be circulated to the absorption and separation unit 350 (discharge flow B9), and the butadiene and solvent are separated and the discharge flow B8 containing the remaining butene is a raw material. It is preferable to include the step of being mixed with butene and introduced into the oxidative dehydrogenation reaction unit 310 because the reaction can proceed continuously.

4 is an additional discharge flow (B4"') to the discharge flow (B4") generated after degassing in FIG. 3, and the discharge flow (B4") is additionally separated from the degassing unit 460 Crude hydrocarbons excluding COx and O ₂ may be included, and the high boiling point component is separated from the crude hydrocarbon while passing through the high boiling point removal unit 470, and the discharge stream (B4"') generated in the high boiling point removal process includes high boiling point substances. The crude hydrocarbon from which is removed is included, and the crude hydrocarbon may more effectively purify butadiene in the purification unit 440.

The high boiling point removal unit may be driven by a conventional distillation column method, for example.

The high boiling point substance may be, for example, an aromatic hydrocarbon such as furan, aldehyde, acetic acid, benzene, or phenol, or styrene.

Referring to FIG. 4, first, a reaction raw material including butene, oxygen (O ₂ ), steam, and a diluted gas (butane) is passed through an oxidation dehydrogenation reaction unit 410, and an oxidative dehydrogenation reaction including butadiene. A product is generated, and is introduced into the cooling separation unit 420 along the flow B1 discharged from the reaction process. At this time, the reaction raw material is purified in the purification process, and then n-butane used as a diluted gas flows into the oxidative dehydrogenation reaction unit 410 along the discharge flow (B7), and the unreacted butenes are discharged after purification. It merges with the raw material butene along (B8) and flows into the oxidation dehydrogenation reaction unit 410.

The flow (B1) discharged from the oxidative dehydrogenation reaction may contain butadiene, n-butane, butene, O ₂ , CO ₂ , H ₂ O, etc., and water is separated by flowing into the cooling separation unit 420.

The discharge flow (B2) generated after the cooling separation may contain butadiene, n-butane, butene, O ₂ , CO _2, etc., and flows into the condensation separation unit 430.

The discharge flow (B3) generated after the condensation separation includes an oxidative dehydrogenation reaction product including uncondensed hydrocarbons after condensing hydrocarbons through compression/cooling using cooling water or low-temperature refrigerant in the condensation separation process. In addition, the other discharge stream (B4') generated after the condensation separation may include condensed n-butane, hydrocarbons including butene and butadiene.

The discharge stream B11 generated after the degassing may include COx and O ₂ additionally separated from the degassing unit 460, and hydrocarbons may be absorbed and separated by being introduced into the absorption and separation unit 450. Another discharge stream (B4") generated after the degassing may be a crude hydrocarbon containing n-butane, butene and butadiene excluding COx and O ₂ further separated by the degassing unit 460, and a high boiling point removal unit ( 470) and separating the high boiling point component from the crude hydrocarbon, and the high boiling point component is removed and the crude hydrocarbon including butadiene may be included in the discharge stream (B4"') generated in the high boiling point removal process. Butadiene may be purified by passing through the discharge stream (B4"') including hydrocarbons through the purification unit 440.

As in FIG. 3, the discharge flow (B5) generated in the absorption separation process includes the discharge flow (B3) including O ₂ and COx separated by the condensation separation unit 430, and O ₂ from the degassing unit 460. , O ₂ , COx, etc. remaining after selective absorption and removal of hydrocarbons such as butadiene or butenes contained in the discharge stream (B11) including COx, etc. may be included. Another discharge stream (B6') generated after the absorption separation includes the absorption of crude hydrocarbons including n-butane, butene and butadiene, etc., excluding COx and O ₂ from the absorption separation unit 450 into a solvent, It is introduced into the degassing unit 460.

The discharge flow (B7) generated after separation and purification of butadiene passing through the purification unit 440 may contain an abundant amount of remaining n-butane, and to form a recycle flow that is introduced into the oxidation dehydrogenation reaction unit 410 do. The solvent is separated in the purification unit 440 and can be circulated to the absorption and separation unit 450 (discharge flow B9), and the butadiene and solvent are separated and the discharge flow B8 containing the remaining butene is a raw material. It is also preferable to include the step of being mixed with butene and introduced into the oxidative dehydrogenation reaction unit 410 because the reaction can proceed continuously.

5 is a replacement of the discharge flow (B11) generated after degassing of FIG. 3 with another discharge flow (B11'), and COx and O ₂ separated by the degassing unit 560 are converted to the absorption and separation unit 550. By introducing it into the condensation system without sending, the amount of solvent required in the absorption and separation unit 550 may be reduced by recondensing the hydrocarbons contained in the discharge stream B11 ′ after the degassing process in the condensation separation unit 530.

The condensation system refers to a system including a compressor 531, a heat exchanger 532, and a condensation separator 530.

Referring to FIG. 5, first, a reaction raw material including butene, oxygen (O ₂ ), steam, and a dilute gas (butane) is passed through an oxidation dehydrogenation reaction unit 510, and an oxidative dehydrogenation reaction including butadiene. A product is generated, and is introduced into the cooling separation unit 520 along the flow B1 discharged from the reaction process. At this time, the reaction raw material was purified in the purification process and then merged with the discharge stream (B7) containing n-butane, which was generated after the purification process, and flowed into the oxidation dehydrogenation reaction unit 510. The reactive butenes merge with the raw material butenes along the discharge flow B8 and flow into the oxidative dehydrogenation reaction unit 510.

The flow B1 discharged from the reaction process may contain butadiene, n-butane, butene, O ₂ , CO ₂ , H ₂ O, etc., and water is separated by flowing into the cooling separation unit 520.

The discharge flow (B2) generated after the cooling separation may contain butadiene, n-butane, butene O ₂ , CO ₂ , and the like, and flows into the condensation separation unit 530.

The discharge flow (B3) generated after the condensation separation includes an oxidative dehydrogenation reaction product including uncondensed hydrocarbons after condensing hydrocarbons through compression/cooling using cooling water or low-temperature refrigerant in the condensation separation process. The discharge stream (B4') generated after the condensation separation may contain hydrocarbons including condensed n-butane and butadiene.

COx and O ₂ may be further separated while passing through the degassing unit 560. The discharge stream (B11') generated after the degassing may be recondensed in the condensation separation unit 530 by introducing COx and O ₂ additionally separated from the degassing unit 560 into the condensation system, and generated after the degassing. Another discharge stream (B4") may include n-butane, butene and crude hydrocarbons including butadiene, excluding COx and O ₂ further separated from the degassing unit 560, and input to the purification unit 540 Thus, butadiene can be purified.

In the discharge stream (B5) generated in the absorption separation process, hydrocarbons such as butadiene or butenes contained in the discharge stream (B3) including O ₂ and COx separated from the condensation separation unit 530 are selectively absorbed and removed. The remaining O ₂ , COx, etc. may be included, and n-butane, butene and butadiene excluding COx and O ₂ from the absorption and separation unit 550 may be included in another discharge stream (B6′) generated in the absorption separation process. The included crude hydrocarbon is absorbed by the solvent and is introduced into the degassing unit 560.

The discharge flow (B7) generated after the butadiene separation and stagnation passing through the purification unit 540 may contain an abundant amount of remaining n-butane, and to form a recycle flow that is introduced into the oxidation dehydrogenation reaction unit 510 do. The solvent is separated in the purification unit 540 and can be circulated to the absorption and separation unit 550 (discharge flow B9), and the butadiene and solvent are separated and the discharge flow B8 containing the remaining butene is, It is preferable to include the step of being mixed with butene and introduced into the oxidative dehydrogenation reaction unit 510 because the reaction can proceed continuously.

6 is a replacement of the discharge flow (B11) generated after degassing of FIG. 4 with another discharge flow (B11'), and COx and O ₂ separated by the degassing unit 660 are converted to the absorption and separation unit 550. By introducing into the condensation system without sending, the hydrocarbons contained in the discharge stream (B11') can be recondensed to reduce the amount of solvent required in the absorption and separation unit 650.

The condensation system refers to a system including a compressor 631, a heat exchanger 632, and a condensation separator 630.

Referring to FIG. 6, first, a reaction raw material including butene, oxygen (O ₂ ), steam, and a dilute gas (butane) is passed through an oxidation dehydrogenation reaction unit 610, and an oxidative dehydrogenation reaction including butadiene. A product is generated, and is introduced into the cooling separation unit 620 along the flow B1 discharged from the reaction process. At this time, the reaction raw material is purified in the purification process, and the gas containing n-butane, which is generated after the purification process, flows into the oxidative dehydrogenation reaction unit 610 along the discharge flow (B7). The unreacted butenes merge with the raw material butenes along the discharge stream B8 and flow into the oxidation dehydrogenation reaction unit 610.

The flow (B1) discharged from the reaction process may contain butadiene, n-butane, butene, O ₂ , CO ₂ , H ₂ O, etc., and water is separated by flowing into the cooling separation unit 620.

The discharge flow (B2) generated after the cooling separation may contain butadiene, n-butane, butene, O ₂ , CO _2, etc., and flow into the condensation separation unit.

The discharge flow (B3) generated after the condensation separation includes an oxidative dehydrogenation reaction product including uncondensed hydrocarbons after condensing hydrocarbons through compression/cooling using cooling water or low-temperature refrigerant in the condensation separation process. The discharge stream (B4') generated after condensation separation may contain condensed n-butane, hydrocarbons including butene and butadiene, and flows into the degassing unit 660.

COx and O ₂ can be additionally separated while passing through the degassing unit 660, and the discharge stream (B11') generated after the degassing is added to the condensation system additionally separated COx and O ₂ in the degassing unit 660 Thus, it can be recondensed in the condensation separation unit 630, and in another discharge stream (B4”) generated after the degassing, n-butane, butene and butene excluding COx and O ₂ further separated by the degassing unit 660 Crude hydrocarbons including butadiene may be included, and high boiling point substances are separated from the crude hydrocarbons while passing through the high boiling point removal unit 670, and the discharge stream (B4"') generated in the high boiling point removal process includes crude hydrocarbons In addition, butadiene may be purified by passing the crude hydrocarbon through the purification unit 640.

As shown in FIG. 4, the discharge flow (B5) generated in the absorption separation process includes hydrocarbons such as butadiene or butenes included in the discharge flow (B3) including O ₂ and COx separated by the condensation separation unit 630. The remaining O ₂ , COx, etc. may be included after selective absorption and removal, and the other discharge flow (B6') generated after the absorption and separation includes n-butane and butene excluding COx and O ₂ from the absorption and separation unit 650. And hydrocarbons including butadiene and the like are selectively absorbed by a solvent. The discharge flow (B7) generated after separation and purification of butadiene passing through the purification unit 640 may contain an abundant amount of remaining n-butane, and a recycle flow that is introduced into the oxidation dehydrogenation reaction unit 610 is formed. .

The solvent is separated in the purification unit 640 and can be circulated to the absorption and separation unit 650 (discharge flow (B9)), butadiene and the solvent are separated and the discharge flow (B8) containing the remaining butene It is also preferable to include the step of being mixed with butene and introduced into the oxidative dehydrogenation reaction unit 610 to allow the reaction to proceed continuously.

As an example of the manufacturing apparatus used in the manufacturing method, referring to FIG. 2 below, a reaction raw material including butene, oxygen (O ₂ ), steam, and a dilution gas (butane) is subjected to oxidation dehydrogenation reaction unit 210 A cooling separation unit 220 for separating water from an oxidation dehydrogenation reaction product including butadiene obtained from the oxidation dehydrogenation reaction by passing through the furnace; A condensation separation unit 230 for condensing hydrocarbons from the oxidative dehydrogenation reaction product from which water is separated; An absorption separation unit 250 for selectively absorbing and recovering hydrocarbons from an oxidation dehydrogenation reaction product including hydrocarbons not condensed in the condensation separation unit 230; Including; n-butane condensed in the condensation separation unit 230, a purification unit 240 for separating butadiene from hydrocarbons containing butene and butadiene; including, n excluding butadiene separated by the purification unit 240 -The gas containing butane is configured to have an exhaust flow (B7) in which the gas containing butane is re-introduced into the oxidative dehydrogenation reaction unit 210, and the gas containing butenes excluding butadiene separated by the purification unit 240 is a raw material It is configured to have a discharge flow (B8) re-introduced into the oxidation dehydrogenation reaction unit 210 together with butene.

In the absorption and separation unit 250, the discharge flow (B6) including that crude hydrocarbons including n-butane, butene and butadiene, excluding COx and O ₂ are selectively absorbed in a solvent, is transferred to the condensation separation unit 230. It is configured to be supplied.

As an example of another manufacturing apparatus, referring to FIG. 3 below, a reaction raw material including butene, oxygen (O ₂ ), steam, and a diluent gas (butane) is passed through the oxidation dehydrogenation reaction unit 310 to oxidize. A cooling separation unit 320 for separating water from an oxidative dehydrogenation reaction product including butadiene obtained from the dehydrogenation reaction; A condensation separation unit 330 for condensing hydrocarbons from the oxidation dehydrogenation reaction product from which water is separated; An absorption separation unit 350 for selectively absorbing and recovering hydrocarbons from an oxidation dehydrogenation reaction product including hydrocarbons not condensed in the condensation separation unit 330; In the discharge stream containing n-butane, butene and butadiene condensed in the condensation separation unit 330 and some COx, O ₂ containing COx, O ₂ and n-butane, butene and butadiene A degassing unit 360 for separating hydrocarbons; And a purification unit 340 for separating butadiene from crude hydrocarbons including n-butane, butene and butadiene excluding COx and O ₂ separated by the degassing unit 360; including, in the purification unit 340 An exhaust stream (B9) in which the solvent is separated and circulated to the absorption and separation unit 350, and an exhaust stream in which the gas containing n-butane excluding butadiene and the solvent is re-introduced into the oxidative dehydrogenation reaction unit 310 (B7). ), and the gas containing butenes excluding butadiene separated by the purification unit 340 is configured to have a discharge flow B8 that is re-introduced to the oxidation dehydrogenation reaction unit 310 together with the raw material butene. .

The discharge stream (B11) containing COx and O ₂ separated by the degassing unit 360 circulates to the absorption and separation unit 350, excluding COx and O ₂ separated by the absorption and separation unit 350 -The discharge stream (B6') containing the crude hydrocarbon containing butane, butene and butadiene is configured to be recycled to the degassing unit (360).

As an example of another manufacturing apparatus, referring to FIG. 4 below, a reaction raw material including butene, oxygen (O ₂ ), steam, and diluent gas (butane) is passed through the oxidation dehydrogenation reaction unit 410 to oxidize. A cooling separation unit 420 for separating water from an oxidation dehydrogenation reaction product containing butadiene obtained from the dehydrogenation reaction; A condensation separator 430 for condensing hydrocarbons from the oxidative dehydrogenation reaction product from which water is separated; An absorption separation unit 450 for selectively absorbing and recovering hydrocarbons from an oxidation dehydrogenation reaction product including hydrocarbons not condensed in the condensation separation unit 430; In the discharge stream containing n-butane, butene and butadiene-containing hydrocarbons and some CO ₂ and O ₂ condensed in the condensation separation unit 430, COx, O ₂ and n-butane, butene and butadiene are included. A degassing unit 460 for separating the hydrocarbons; A high boiling point removal unit 470 for removing high boiling point substances from crude hydrocarbons including n-butane, butene and butadiene excluding COx and O ₂ separated by the degassing unit 460; And a purification unit 440 for separating butadiene from crude hydrocarbons including n-butane, butene and butadiene from which the high boiling point material has been removed by the high boiling point removal unit 470, and in the purification unit 440 The exhaust stream (B9) in which the solvent is separated and circulated to the absorption and separation unit 450, and the gas containing n-butane excluding butadiene and the solvent from the purification unit 440 are transferred to the oxidative dehydrogenation reaction unit 410. It is configured to have a re-introduced discharge flow (B7), and the gas containing butenes excluding butadiene separated in the purification unit 440 is discharged flow that is re-introduced to the oxidation dehydrogenation reaction unit 410 together with the raw material butene It is configured to have (B8).

The discharge stream (B11) containing COx and O ₂ separated by the degassing unit 460 circulates to the absorption and separation unit 450, and n-butane excluding COx and O ₂ from the absorption and separation unit 450 , The discharge stream (B6') containing the crude hydrocarbons including butene and butadiene selectively absorbed in the solvent is configured to be recycled to the degassing unit 460.

The discharge stream (B4") containing the crude hydrocarbons including n-butane, butene and butadiene separated in the degassing unit 460 is introduced into the high boiling point removing unit 470, and the high boiling point is high in the high boiling point removing unit 470. It is configured such that the discharge stream (B4"') containing the crude hydrocarbon from which the point substance is separated is introduced into the purification unit 440.

As an example of another manufacturing apparatus, referring to FIG. 5 below, a reaction raw material including butene, oxygen (O ₂ ), steam, and a dilution gas (butane) is passed through the oxidation dehydrogenation reaction unit 510 to be oxidized. A cooling separation unit 520 for separating water from an oxidative dehydrogenation reaction product including butadiene obtained from the dehydrogenation reaction; A condensation separation unit 530 for condensing hydrocarbons from the oxidative dehydrogenation reaction product from which water is separated; An absorption separation unit 550 for selectively absorbing and recovering hydrocarbons from an oxidation dehydrogenation reaction product including hydrocarbons not condensed in the condensation separation unit 530; A degassing unit 560 for separating hydrocarbons condensed in the condensation separation unit 530 and hydrocarbons including COx and O ₂ and n-butane, butene and butadiene in the discharge stream including some COx and O ₂ ; And a purification unit 540 for separating butadiene from crude hydrocarbons containing n-butane, butene and butadiene excluding COx and O ₂ separated by the degassing unit 560; including, in the purification unit 540 An exhaust stream (B9) in which the solvent is separated and circulated to the absorption and separation unit 550, and an exhaust stream in which the gas containing n-butane excluding butadiene and the solvent is re-introduced to the oxidative dehydrogenation reaction unit 510 (B7). ), and the gas including butenes excluding butadiene separated by the purification unit 540 is configured to have a discharge flow B8 that is re-introduced to the oxidation dehydrogenation reaction unit 510 together with the raw material butene. .

The discharge stream (B11') containing COx and O ₂ separated by the degassing unit 560 flows into the condensation system, is recondensed and separated by the condensation separation unit 530, and separated by the absorption separation unit 550 The discharge stream (B6') including that crude hydrocarbons including n-butane, butene and butadiene, excluding COx and O ₂ , are selectively absorbed in the solvent, is configured to be recycled to the degassing unit 560.

As an example of another manufacturing apparatus, referring to FIG. 6 below, a reaction raw material including butene, oxygen (O ₂ ), steam, and a dilution gas (butane) is passed through the oxidation dehydrogenation reaction unit 610 to oxidize. A cooling separation unit 620 for separating water from an oxidation dehydrogenation reaction product containing butadiene obtained from the dehydrogenation reaction; A condensation separator 630 for condensing hydrocarbons from the oxidative dehydrogenation reaction product from which water is separated; An absorption separation unit 650 for selectively absorbing and recovering hydrocarbons from an oxidation dehydrogenation reaction product including hydrocarbons not condensed in the condensation separation unit 630; In the discharge stream containing n-butane condensed in the condensation separation unit 630, crude hydrocarbons including butene and butadiene, and some CO ₂ and O ₂ , COx and O ₂ and n-butane, butene and butadiene are included. A degassing unit 660 for separating the crude hydrocarbons; And a high boiling point removal unit 670 for removing high boiling point substances from crude hydrocarbons including n-butane, butene and butadiene, excluding COx and O ₂ separated by the degassing unit 660. And a purification unit 640 for separating butadiene from the crude hydrocarbon containing n-butane, butene and butadiene from which the high boiling point material has been removed by the high boiling point removal unit 670; and a solvent in the purification unit 640 The gas containing n-butane excluding butadiene and a solvent from the purification unit 640 and the discharge stream B9 that is separated and circulated to the absorption and separation unit 650 are recycled to the oxidative dehydrogenation reaction unit 610. It is configured to have an input discharge flow (B7), and the gas containing butenes excluding butadiene separated from the purification unit 640 is a discharge flow that is re-introduced to the oxidative dehydrogenation reaction unit 610 along with the raw material butene ( B8) is configured to have.

The discharge stream (B11') containing COx and O ₂ separated by the degassing unit 660 is introduced into the condensation system and recondensed to the condensation separation unit 630, and the COx separated by the absorption separation unit 650 The discharge stream (B6') containing n-butane excluding and O ₂ , crude hydrocarbons containing butene and butadiene selectively absorbed in a solvent is configured to be recycled to the degassing unit 660.

The discharge stream (B4") containing the crude hydrocarbon containing n-butane, butene and butadiene separated in the degassing unit 660 is introduced into the high boiling point removal unit 670, and the high boiling point is high in the high boiling point removal unit 670. The discharge stream (B4"') containing the crude hydrocarbon from which point components are separated is configured to be introduced into the refining unit 640.

The heat generated by incineration of the COx and O ₂ separated by the absorption and separation units 250, 350, 450, 550, 650 and unabsorbed hydrocarbons is converted into raw material heat-up or purification units 240, 340 , 440, 540, 640 between the absorption separation unit (250, 350, 450, 550, 650) and the oxidation dehydrogenation reaction unit (210, 310, 410, 510, 610), or the absorption separation unit (250, 350, 450, 550, 650) and the condensation separation unit (240, 340, 440, 540, 640), or the absorption separation unit (250, 350, 450, 550, 650) and the oxidative dehydrogenation A heat exchange means may be provided between the reaction units 210, 310, 410, 510, and 610 and the condensation separation units 240, 340, 440, 540, and 640.

Using the butadiene manufacturing method and the manufacturing apparatus used therein described so far, it is possible to compensate for the disadvantages of the manufacturing method using nitrogen as a dilution gas in the conventional butadiene manufacturing process and increase the treatment effect, and reduce the energy consumption of the processing process. By minimizing, energy efficiency can be maximized. In addition, the method for producing butadiene of the present invention can be used directly for purification/manufacturing of materials for various purposes (ACN, NMP, DMF, etc.), so it can be applied to various processes.

Hereinafter, a preferred embodiment is presented to aid the understanding of the present invention, but the following examples are only illustrative of the present invention, and it is obvious to those skilled in the art that various changes and modifications are possible within the scope and spirit of the present invention, It is natural that such modifications and modifications fall within the appended claims.

[ Example ]

Example One

Using butane as a diluting gas using the manufacturing apparatus of FIG. 2 and using raffinate-3 having the composition of Table 1 below as a raw material, butene: oxygen = 1: 0.9, butene: water vapor = 1: 5 under a ferrite catalyst , Butene:butane = 1:4 through the oxidation dehydrogenation reaction of the reaction raw material to obtain an oxidative dehydrogenation reaction product containing butadiene, and after removing water from the cooling and separating unit, the compressed discharge temperature is 80°C. , The pressure was 6.5KCG, the cooling temperature was 40°C, and the hydrocarbons were condensed using cooling water.

Afterwards, a solvent is used to recover butadiene contained in the uncondensed gas in the absorption and separation section using DMF to absorb butadiene loss in the discharge stream (B5) to approximately 0.5% of the production volume. Butadiene having a yield of 97.5% and a purity of 99.5% by weight was prepared.

At this time, the discharge flow of the oxidative dehydrogenation reaction unit is measured by gas chromatography, and the composition in the discharge flows (B1 to B8) of the cooling separation unit, condensation separation unit, absorption separation unit, and purification unit is used as a process simulator (AspenPlus). It was calculated and shown in Table 2 below.

Example 2

Except for using a solvent to make the butadiene loss to the discharge stream (B5) in Example 1 approximately 0.1% of the production amount, the final butadiene yield from butene was 97.9% and purity 99.5% by weight under the same conditions as in Example 1 above. Butadiene was prepared.

Comparative example One

Except for the process of absorption and separation in Example 1, butadiene having a final butadiene yield of 89% and a purity of 99.5% by weight was prepared from butene under the same conditions as in Example 1.

Comparative example 2

Except that the cooling temperature was set to 0°C using a refrigerant in the absorption separation process and condensation separation process in Example 1, the final butadiene yield from butene was 96.5% and purity 99.5% by weight under the same conditions as in Example 1. Butadiene was prepared.

[Test Example]

In Examples 1 and 2 and Comparative Examples 1 and 2, the energy consumption and butadiene loss in the condensation separation unit and the purification unit during the production process of butadiene from butene were calculated by a process simulator (AspenPlus) and shown in Table 4 below.

Furtherance mole% weight% 1-butene 0.00 0.00 Trans-2-butene 43.20 42.77 Cis-2-butene 28.80 28.51 n-butane 28.00 28.72

B1 B2 B3 B4 MW Kg/hr wt% Kg/hr wt% Kg/hr wt% Kg/hr wt% N2 28.0 0 0 0 0 1.6 0.2 0 0.0 CO2 44.0 145.5 2.2 145.5 3.0 196.6 25.2 0.3 0.0 CO 28.0 9.3 0.1 9.3 0.2 9.4 1.2 0.0 0.0 O2 32.0 73.8 1.1 73.8 1.5 74.6 9.6 0.0 0.0 butane 58.1 3740.0 57.1 3740.0 78.2 401.8 51.5 3548.8 81.5 1,3-butadiene 54.1 712.0 10.9 712.0 14.9 85.6 11.0 708.5 16.3 Butene 56.1 98.9 1.5 98.9 2.1 10.1 1.3 96.9 2.2 HB 72.1 11.3 0.2 0.0 0.0 0.0 0.0 0.0 0.0 water 18.0 1760.6 26.9 0.0 0.0 0.0 0.0 0.0 0.0 Sum 6551.6 100 4779.7 100 779.5 100 4354.6 100

B5 B6 B7 B8 1,3-butadiene Kg/hr wt% Kg/hr wt% Kg/hr wt% Kg/hr wt% Kg/hr wt% N2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 CO2 145.2 34.2 56.8 15.7 0.0 0.0 0.0 0.0 0.0 0.0 CO 9.3 2.2 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 O2 73.8 17.4 1.2 0.3 0.0 0.0 0.0 0.0 0.0 0.0 butane 191.2 45.0 212.7 58.9 3548.8 99.5 0.0 0.0 0.0 0.0 1,3-butadiene 3.6 0.8 82.1 22.7 7.1 0.2 7.1 7.8 694.3 99.5 Butene 2.0 0.5 8.1 2.3 9.7 0.3 83.8 92.2 3.5 0.5 HB 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 water 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Sum 425.1 100 361.0 100 3565.6 100 90.8 100 697.8 100

As shown in Tables 2 and 3, Example 1 according to the present invention has a yield of 99.5% by weight of butadiene, which is much higher than 89% by weight of Comparative Example 1, and 85.6 kg/hr of uncondensed butadiene in the condensation separation unit. The butadiene was recovered through absorption and separation, and the loss was reduced to 3.6 kg/hr, thereby improving the butadiene yield, which resulted in excellent economical efficiency.

division Example 1 Example 2 Comparative Example 1 Comparative Example 2 Condensation process and
Absorption process Condensation process and
Absorption process Condensation process Condensation process Condensation temperature
(℃) 40 40 40 0 butadiene
Loss (B5)
(Kg/hr) 3.6 0.7 62.7 10.9 condensation
Separation Refinery Condensation and
absorption
Separation Refinery condensation
Separation Refinery condensation
Separation Refinery vapor Gcal/hr 0.5 1.7 0.6 1.7 0.2 1.7 0.2 1.7 cooling water Gcal/hr 0.9 0.9 0.9 1.0 0.5 0.7 0.5 0.8 Refrigerant Gcal/hr 0.3 0.0 0.4 0.0 0.0 0.0 0.1 0.0 menstruum Ton/hr 2.2 12.2 3.3 12.2 0.0 14.5 0.0 14.5 Electricity kW 118.8 51.2 118.8 51.3 106.0 49.0 106.0 50.8

As shown in Table 4, in Examples 1 and 2 in which absorption separation was performed after condensation separation according to the present invention, the loss of butadiene in the flow (B5) discharged from the absorption separation unit was significantly reduced, thereby improving economic efficiency. In addition, compared to Comparative Example 2 in which the condensation temperature was lowered, Examples 1 and 2, in which the absorption separation process was performed, reduced butadiene loss, and thus the butadiene recovery effect was excellent.

In addition, while the loss of butadiene in the discharge flow (B5) in Examples 1 and 2 was significantly reduced compared to Comparative Examples 1 and 2, the amount of solvent used in the condensation and absorption separation unit and the purification unit was similar to that of Comparative Examples 1 and 2. Was. This is because in Examples 1 and 2, since the discharge flow including the solvent selectively absorbing butadiene from the absorption and separation unit flows into the purification unit through the condensation separation unit, the amount of solvent required in the purification unit is reduced.

110, 210, 310, 410, 510, 610: oxidation dehydrogenation reaction section
130, 250, 350, 450, 550, 650: absorption and separation unit
120, 320, 420, 520, 620: cooling separator
230, 330, 430, 530, 630: condensation separation unit
140, 240, 340, 440, 540, 640: refining unit
360, 460, 560, 660: degassing unit
470, 670: high boiling point removal unit
531, 631: compressor
532, 632: heat exchanger

Claims (19)

Passing a reaction raw material containing butene, oxygen (O ₂ ), steam, and a diluted gas through an oxidation dehydrogenation reaction unit to generate an oxidative dehydrogenation reaction product including butadiene, and
Separating water while passing the oxidative dehydrogenation reaction product including butadiene through a cooling separation unit,
Condensing hydrocarbons while passing the oxidative dehydrogenation reaction product from which the water is separated through a condensation separator,
Separating COx and O ₂ while passing an oxidative dehydrogenation reaction product including hydrocarbons not condensed in the condensation separation unit through an absorption separation unit,
The n-butane condensed in the condensation and separating unit, the crude hydrocarbon containing butene and butadiene, is passed through the purification unit to separate butadiene or pass through the degassing unit to further separate COx and O ₂ and then n-butane and butene. And separating butadiene while passing the crude hydrocarbon containing and butadiene through the purification unit,
Gas containing n-butane excluding butadiene separated in the purification unit is re-introduced into the oxidation dehydrogenation reaction unit,
The butadiene is separated from the purification unit and the discharge stream containing the remaining butene is mixed with raw material butene and introduced into the oxidation dehydrogenation reaction unit, wherein the dilution gas is butane. The method of claim 1,
A method for producing butadiene, characterized in that oxygen (O ₂ ) contained in the reaction raw material is introduced in the form of a gas having a purity of 90% or more. The method of claim 1,
The reaction conditions in the oxidative dehydrogenation reaction section are butene: oxygen: water vapor: diluted gas = 1: 0.5 to 3: 0.05 to 20: a method for producing butadiene, characterized in that the molar ratio of 0.05 to 20. The method of claim 1,
The condensation separation is a one-stage compression structure, a multi-stage compression structure of one to two stages, or a multi-stage compression structure of two to ten stages, and a compression discharge temperature of 50 to 250°C. The method of claim 1,
The refrigerant used in the condensation separation is at least one selected from the group consisting of cooling water, ethylene glycol, an aqueous solution of ethylene glycol having a concentration of 20 to 100% by weight, propylene glycol, an aqueous solution of propylene glycol having a concentration of 30 to 100% by weight, and a propylene-based solvent. Method for producing butadiene, characterized in that. The method of claim 1,
Injecting COx and O ₂ further separated from the degassing unit into the absorption and separation unit,
Method for producing butadiene, characterized in that the step of introducing a crude hydrocarbon containing n-butane and butadiene excluding COx and O ₂ separated by the degassing unit into the purification unit. The method of claim 1,
Injecting COx and O ₂ further separated from the degassing unit into the absorption and separation unit,
Separating the crude hydrocarbon while passing the crude hydrocarbon containing n-butane, butene and butadiene excluding COx and O ₂ further separated in the degassing unit through a high boiling point removal unit,
The method for producing butadiene, characterized in that the step of introducing the crude hydrocarbon separated in the high boiling point removal unit into the purification unit. The method of claim 1,
Injecting the additionally separated COx and O ₂ in the degassing unit into a condensation system,
Injecting crude hydrocarbons containing n-butane and butadiene excluding COx and O ₂ further separated from the degassing unit into the purification unit, or separating the crude hydrocarbons while passing through the high boiling point removing unit and then introducing them to the purification unit, Butadiene production method, characterized in that consisting of. The method of claim 1,
The oxidative dehydrogenation reaction unit contains butene, oxygen (O ₂ ), steam, and a gas containing n-butane that is re-introduced to the oxidation dehydrogenation reaction unit as a residue from which butadiene is separated from the purification unit. A method for producing butadiene, characterized in that it is driven under isothermal or adiabatic conditions at a reaction temperature of 150 to 650°C using a ferritic catalyst or an iron catalyst as a reaction raw material. The method of claim 1,
The cooling separating unit is a method for producing butadiene, characterized in that driven by a direct cooling method (quencher) of rapid cooling or an indirect cooling method. The method of claim 1,
The absorption and separation unit is a method for producing butadiene, characterized in that driven in an absorption method using a solvent capable of selectively absorbing COx and O ₂ to separate. The method of claim 1,
The method for producing butadiene, wherein the degassing unit is driven by stripping or degassing using a general column. The method of claim 1,
The absorption and separation unit discharge flow in which the crude hydrocarbon containing n-butane and butadiene excluding COx and O ₂ is re-introduced to the condensation separation unit or the degassing unit; and the purification unit discharge flow through which the solvent is separated and circulated to the absorption separation unit. A method for producing butadiene that is configured to have. An oxidative dehydrogenation reaction unit for obtaining an oxidative dehydrogenation reaction product including butadiene by oxidatively dehydrogenating a reaction raw material including butene, oxygen (O ₂ ), steam, and dilute gas;
A cooling separation unit for separating water from an oxidative dehydrogenation reaction product including butadiene obtained from the oxidative dehydrogenation reaction;
A condensation separator for condensing hydrocarbons from the oxidative dehydrogenation reaction product from which water is separated;
An absorption separation unit for separating COx and O ₂ from an oxidation dehydrogenation reaction product including hydrocarbons not condensed in the condensation separation unit; And
Including; a purification unit for separating butadiene from the crude hydrocarbon containing n-butane, butene and butadiene condensed in the condensation separation unit,
Gas containing n-butane excluding butadiene separated in the purification unit is re-introduced into the oxidation dehydrogenation reaction unit,
Butadiene is separated from the purification unit and the remaining butene is mixed with raw material butene and introduced into the oxidative dehydrogenation reaction unit, wherein the dilution gas is butane. The method of claim 14,
An apparatus for producing butadiene, characterized in that it comprises an exhaust stream in which hydrocarbons containing n-butane and butadiene, excluding COx and O ₂ separated by the absorption and separation unit, are supplied to the degassing unit. The method of claim 14,
Degassing to remove the n- butane, butene and butadiene and COx and O ₂ in the crude hydrocarbon include, n- butane, the hydrocarbon crude contains a butene and butadiene, except for COx and O ₂ separated from the absorbing separating section; And a discharge flow for re-introducing the COx and O ₂ separated by the degassing unit into the absorption and separation unit. The method of claim 14,
Degassing to remove the n- butane, butene and butadiene and COx and O ₂ in the crude hydrocarbon include, n- butane, the hydrocarbon crude contains a butene and butadiene, except for COx and O ₂ separated from the absorbing separating section; And a discharge flow for introducing the COx and O ₂ separated from the degassing unit into the condensing system. The method of claim 16 or 17,
A high boiling point removal unit for separating a high boiling point component from the crude hydrocarbon containing n-butane, butene and butadiene separated by the degassing unit; And
An apparatus for producing butadiene, further comprising: an exhaust stream in which the crude hydrocarbon separated by the high boiling point removal unit is introduced into the refining unit. The method of claim 14,
Butadiene, characterized in that it comprises: an exhaust flow through which the solvent separated from the purification unit is circulated to the absorption and separation unit; and an exhaust flow through which butadiene and a gas containing n-butane excluding the solvent are re-introduced into the oxidation dehydrogenation reaction unit. Manufacturing equipment.

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