阅读说明：本技术 乙醇回收和联产乙二醇的方法 (Method for recovering ethanol and co-producing ethylene glycol ) 是由 胡帅 胡松 杨卫胜 于 2018-08-17 设计创作，主要内容包括：本发明涉及乙醇回收和联产乙二醇的方法,主要解决现有技术中存在的乙醇回收分离能耗高和1,4-二氧六环废水处理困难的问题。本发明通过采用将在反应精馏塔上部加入含有水、乙醇和1,4-二氧六环的混合溶液物流,下部加入含有环氧乙烷的环氧乙烷物流,混合溶液物流的进料位置到反应精馏塔塔顶为精馏段,混合溶液物流与环氧乙烷物流进料位置之间反应段,环氧乙烷物流进料位置到反应精馏塔塔釜为提馏段；精馏段填充填料,反应段填充催化剂和填料,提馏段填充填料；环氧乙烷与水反应生产乙二醇；通过反应精馏塔的精馏作用,反应精馏塔塔顶得到含乙醇和1,4-二氧六环的粗乙醇物流,塔釜得到乙二醇产品的技术方案较好地解决了该问题,可用于乙醇回收工艺生产中。(The invention relates to a method for recovering ethanol and co-producing ethylene glycol, and mainly solves the problems of high energy consumption of ethanol recovery and separation and difficult treatment of 1,4-dioxane wastewater in the prior art. Adding a mixed solution material flow containing water, ethanol and 1,4-dioxane into the upper part of a reactive distillation tower, adding an ethylene oxide material flow containing ethylene oxide into the lower part of the reactive distillation tower, wherein the feeding position of the mixed solution material flow to the top of the reactive distillation tower is a distillation section, a reaction section is arranged between the mixed solution material flow and the feeding position of the ethylene oxide material flow, and the feeding position of the ethylene oxide material flow to the bottom of the reactive distillation tower is a stripping section; the rectifying section is filled with filler, the reaction section is filled with catalyst and filler, and the stripping section is filled with filler; ethylene oxide reacts with water to produce ethylene glycol; the technical scheme that the crude ethanol material flow containing ethanol and 1,4-dioxane is obtained at the top of the reactive distillation tower through the distillation function of the reactive distillation tower, and the ethylene glycol product is obtained at the bottom of the reactive distillation tower better solves the problem, and can be used in the production of an ethanol recovery process.)

1. A method for recovering ethanol and co-producing ethylene glycol, comprising the steps of:

a) adding a mixed solution material flow containing water, ethanol and 1,4-dioxane into the upper part of a reactive rectifying tower, adding an ethylene oxide material flow containing ethylene oxide into the lower part of the reactive rectifying tower, wherein the feeding position of the mixed solution material flow to the top of the reactive rectifying tower is a rectifying section, a reaction section is arranged between the mixed solution material flow and the feeding position of the ethylene oxide material flow, and the feeding position of the ethylene oxide material flow to the bottom of the reactive rectifying tower is a stripping section;

b) the rectifying section is filled with filler, the reaction section is filled with catalyst and filler, and the stripping section is filled with filler;

c) ethylene oxide reacts with water to produce ethylene glycol;

d) under the rectification action of the reactive distillation column, a crude ethanol material flow containing ethanol and 1,4-dioxane is obtained at the top of the reactive distillation column, and an ethylene glycol product is obtained at the bottom of the column.

2. The method for recovering ethanol and coproducing ethylene glycol as claimed in claim 1, wherein the crude ethanol stream is sent to an ethanol recovery tower, an ethanol stream is obtained at the top of the tower, and a 1,4-dioxane stream is obtained at the bottom of the tower.

3. The ethanol recovery and co-production process of ethylene glycol according to claim 1, characterized in that the mixed solution comprises the following components in weight percentage: 50-95% of ethanol, 1-25% of 1,4-dioxane and 1-25% of water.

4. The method for recovering ethanol and coproducing ethylene glycol as claimed in claim 1, wherein the operating pressure at the top of the reactive distillation tower is 0.20-1.20 MPaA, the operating temperature at the top of the reactive distillation tower is 95-160 ℃, the operating pressure at the bottom of the reactive distillation tower is 0.20-1.20 MPaA, the operating temperature at the bottom of the reactive distillation tower is 200-310 ℃, and the reflux ratio is 1-10.

5. The method for recovering ethanol and coproducing ethylene glycol as claimed in claim 1, wherein the operating pressure of the ethanol recovery tower is 0.20-1.0 MPaA, and the tower top temperature is 35-160 ℃.

6. The method for recovering ethanol and coproducing ethylene glycol as claimed in claim 1, wherein the operating pressure of the ethanol recovery tower is preferably 0.20-0.7 MPaA, and the tower top temperature is 35-140 ℃.

7. The method for recovering ethanol and coproducing ethylene glycol as claimed in claim 1, wherein the reaction section of the reactive distillation tower is provided with 10-30 theoretical plates.

8. The method for recovering ethanol and coproducing ethylene glycol as claimed in claim 1, wherein the rectifying section of the reactive distillation tower is provided with 10-30 theoretical plates.

9. The method for recovering ethanol and coproducing ethylene glycol as claimed in claim 1, wherein the stripping section of the reactive distillation column has 10-30 theoretical plates.

10. The method for recovering ethanol and co-producing ethylene glycol according to claim 1, wherein the ethanol recovery tower has 20 to 100 theoretical plates.

Technical Field

The invention relates to a method for recovering ethanol and co-producing ethylene glycol, in particular to a process for recovering ethanol from a 1,4-dioxane solvent.

Background

The ethanol is commonly called alcohol, the molecular formula is C2H6O, according to GB/T394.1-2008 industrial alcohol national standard, the top grade is more than or equal to 96% vol, and the first grade is more than or equal to 95% vol; according to GB/T678-2002 anhydrous ethanol national standard, the chemical purity is more than or equal to 99.5 percent wt, and the water content is less than or equal to 0.5 percent wt; the analytical purity is more than or equal to 99.7 percent by weight, and the water content is less than or equal to 0.3 percent by weight; the top grade purity is more than or equal to 99.8 percent by weight, and the water content is less than or equal to 0.2 percent by weight; the ethanol has wide application range, and can be used for preparing acetic acid, beverages, essence, dye, fuel and the like. In medical treatment, ethanol with the volume fraction of 70-75% is also commonly used as a disinfectant and the like, and has wide application in national defense chemical industry, medical treatment and health, food industry, industrial and agricultural production.

The fuel ethanol generally refers to absolute ethanol with the volume concentration of more than 99.5 percent. The fuel ethanol is a clean-burning high-octane fuel and is a renewable energy source. Ethanol is not only an excellent fuel, but also an excellent fuel improver. The excellent characteristics are as follows: ethanol is an oxygen increasing agent of fuel oil, so that the gasoline can increase internal oxygen and be fully combusted, and the aims of energy conservation and environmental protection are fulfilled; the ethanol can also economically and effectively reduce the content of aromatic hydrocarbon and olefin, namely reduce the modification cost of a refinery and achieve the new gasoline standard.

In recent years, the consumption of fuel ethanol has increased due to fluctuations in the price of oil. The fuel ethanol industry in China starts late, but develops rapidly, and the fuel ethanol has wide prospects in China. With the further increase of domestic petroleum demand, energy supply diversification strategies represented by alternative energy sources such as ethanol have become one direction of the energy policy in China. China has become the third major biofuel ethanol producing country and country of application in the world after Brazil and the United states. Fuel ethanol has moved to the way of non-grain ethanol development and has been rapidly developed.

The fuel ethanol has the characteristics of cleanness, renewability and the like, and can reduce the emission of carbon monoxide and hydrocarbon in automobile exhaust. The key points of the fuel ethanol industry in China in the future are to reduce the production cost and reduce government subsidies, so that consumption control standards and product quality technical standards of the biofuel ethanol production process are established, and the fixed-rate standards of the fuel ethanol production consumption, including material consumption, water consumption, energy consumption and the like, are unified, so that the method is a powerful means for reducing cost and improving efficiency.

As a gasoline additive, the octane number of the gasoline can be improved. Generally, the octane number of the motor gasoline is generally required to be 90 or 93, and the octane number of ethanol can reach 111, so that the octane number of the gasoline can be greatly improved by adding fuel ethanol into the gasoline, the blending effect of the ethanol on the octane number of alkane gasoline components (alkylate and light naphtha) is better than that of olefin gasoline components (catalytic cracking gasoline) and aromatic gasoline components (catalytic reforming gasoline), and the antiknock property of the gasoline can be effectively improved by adding the ethanol.

Ethanol, which has an oxygen content of up to 34.7%, can be added to gasoline in smaller amounts than methyl tert-butyl ether (MTBE). 7.7 percent ethanol is added into the gasoline, and the oxygen content reaches 2.7 percent; if 10% ethanol is added, the oxygen content can reach 3.5%, so the ethanol is added to help the gasoline to be completely combusted, and the pollution to the atmosphere is reduced. The fuel ethanol is used for replacing tetraethyl lead as a gasoline additive, so that the pollution of lead in the air can be eliminated; and the MTBE is replaced, so that the pollution to underground water and air can be avoided. In addition, the octane number and the oxygen content of the gasoline are improved, and the ethanol can improve the quality of automobile exhaust and reduce pollution. Generally, when the addition amount of ethanol in gasoline is not more than 15%, the driving performance of the vehicle is not obviously affected, but the content of hydrocarbons, NOx and CO in tail gas is obviously reduced. Research reports on american automotive/oil (AQIRP) show: compared with the conventional gasoline, the gasoline containing 6 percent of ethanol and the new formula of California has the advantages that HC emission can be reduced by 5 percent, CO emission can be reduced by 21-28 percent, NOx emission can be reduced by 7-16 percent, and the emission of toxic gases can be reduced by 9-32 percent.

Ethylene glycol is a very important organic chemical raw material, mainly used for producing polyester fibers (PET), plastics, rubber, polyester paint, adhesives, nonionic surfactants, ethanolamine and explosives, and also used as a solvent, a lubricant, a plasticizer, an antifreezing agent and the like in a large amount, wherein the demand for producing polyester is the largest and the increase is the fastest. The traditional petroleum route adopts ethylene to directly oxidize ethylene to prepare EO, EO is directly hydrated to prepare EG, water is used as a nucleophilic reagent and reacts with EO to generate EG by a substitution ring-opening reaction, and the production technology is mainly monopolized by three companies, namely SHELL, SD and DOW. The current situation of the current Chinese glycol device is as follows: the technical route is backward, the selectivity of the ethylene glycol is low, and the material consumption of the device is high; the water ratio is high, the production process is complex, the flow is long, and the energy consumption is high; the scale is small, and the market competitiveness is not strong. At present, the yield of ethylene glycol in the overseas advanced ethylene oxide hydration device can reach more than 99%, and the unit consumption of ethylene glycol is lower than that in China by 10% (the current situation, the technical progress and the suggestion [ J ] of the chemical process, 2009, (S1)) of the preparation of ethylene glycol by hydrating ethylene oxide.

1,4-dioxane (1,4-dioxane), the molecular formula of which is C4H8O2, is soluble in both water and various organic solvents. The routes for synthesizing 1,4-dioxane are mainly ethylene oxide method, ethylene glycol method and diethylene glycol method. The ethylene glycol method is prepared by co-distilling and dehydrating ethylene glycol and concentrated phosphoric acid. Is a solvent for cellulose acetate, resin, vegetable oil, mineral oil, oil-soluble dye, etc., and is also used for preparing spray paint, varnish, plasticizer, wetting agent, etc.

1,4-dioxane is used as solvent, reaction medium and extractant in the manufacture of medicine, cosmetics, perfume and other special fine chemicals and scientific research. In Japan, the product is mainly used as stabilizer of 1,1, 1-trichloroethane, and the addition amount is 2.5-4%; secondly, the polyurethane/amino acid composite leather is mostly used as a reaction solvent of polyurethane synthetic leather, amino acid synthetic leather and the like. The product has high dissolving power, similar to that of dimethyl formamide, and higher than that of tetrahydrofuran. 1,4-dioxane has the following important uses: 1. form coordination compounds with sulfur trioxide, and can be used as a sulfating agent in the synthesis of a plurality of compounds; 2. used for extracting medicines and pesticides, dewaxing petroleum products and the like; 3. as a dispersant for dyes, a dispersant for wood colorants, and a solvent for oil-soluble dyes; 4. used as a high-purity metal surface treatment agent, etc.

The reactive distillation process combines the reaction and the separation process, has the advantages of simple process flow, low equipment investment and operation cost and the like, and researchers have already carried out theoretical and experimental research from the 30 s of the 20 th century.

Under normal pressure, 1,4-dioxane and ethanol form an azeotrope, the azeotropic composition of which is 1, 4-dioxane: ethanol is 5.1:94.9mole percent, and the azeotropic point temperature is 78.13 ℃; water forms an azeotrope with ethanol, the azeotropic composition being water: ethanol is 10.57:89.43 mole%, and the azeotropic point temperature is 78.15 ℃; the 1,4-dioxane and water form an azeotrope with an azeotropic composition of 1, 4-dioxane: water 36.52:63.48 mole%, azeotropic point temperature 89.47 ℃; 1,4-dioxane, ethanol and water form a ternary azeotrope, the azeotropic composition is 1, 4-dioxane: ethanol: water 4.2:85.3:10.5 mole% and azeotropic temperature 78.08 ℃. Therefore, it is difficult to recover ethanol and 1,4-dioxane from 1,4-dioxane waste water by atmospheric distillation.

In 1943, The Ternary System, Dioxane-Ethanol-Water, reported that two of 1,4-Dioxane, Ethanol and Water form 3 binary azeotropes and three of The 1,4-Dioxane, Ethanol and Water form a Ternary azeotrope, but a separation method and a scheme are not proposed.

Simulation of azeotropic distillation of ethanol, dioxane, methanol and water, chemical industry and engineering, 2015,32 (2): 69-73, aiming at an ethanol-water system containing methanol and 1,4-dioxane, the method of adopting the flow of two azeotropic distillation towers to realize dehydration is provided, cyclohexane is selected as an entrainer, the azeotropic characteristics among the components in the system are analyzed, and the flow simulation software Aspenplus is utilized to carry out simulation calculation on the flow. The results show that the method adopting the two-tower flow can remove the water in the feed to be below 0.05 percent (mass fraction), the methanol in the feed can be discharged from the tower kettle of the recovery tower, and the simulation results are basically consistent with the actual industrial data. The article only relates to azeotropic distillation dehydration and does not relate to the separation of ethanol and 1, 4-dioxane.

CN1473823A the invention discloses a process for producing high-purity 1,4-dioxane, which comprises the steps of taking diethylene glycol as a raw material, dehydrating and cyclizing the raw material by using a liquid-solid phase composite catalyst at normal pressure and at the temperature of 150 ℃ and 200 ℃, adding an entrainer for low-temperature dehydration, adding an impurity removal agent for impurity removal to obtain the high-purity 1,4-dioxane, and preparing the 1,4-dioxane by adopting the processes of catalytic dehydration cyclization, dehydration and impurity removal.

Disclosure of Invention

The invention provides a method for recovering ethanol and co-producing ethylene glycol, which mainly solves the problems of high energy consumption of ethanol recovery and separation and difficult treatment of 1,4-dioxane wastewater in the prior art.

In order to solve the technical problem, the technical scheme adopted by the invention comprises the following steps:

a method for recovering ethanol and co-producing ethylene glycol, comprising the steps of:

a) adding a mixed solution material flow containing water, ethanol and 1,4-dioxane into the upper part of a reactive rectifying tower, adding an ethylene oxide material flow containing ethylene oxide into the lower part of the reactive rectifying tower, wherein the feeding position of the mixed solution material flow to the top of the reactive rectifying tower is a rectifying section, a reaction section is arranged between the mixed solution material flow and the feeding position of the ethylene oxide material flow, and the feeding position of the ethylene oxide material flow to the bottom of the reactive rectifying tower is a stripping section;

b) the rectifying section is filled with filler, the reaction section is filled with catalyst and filler, and the stripping section is filled with filler;

c) ethylene oxide reacts with water to produce ethylene glycol;

d) under the rectification action of the reactive distillation column, a crude ethanol material flow containing ethanol and 1,4-dioxane is obtained at the top of the reactive distillation column, and an ethylene glycol product is obtained at the bottom of the column.

In the technical scheme of the invention, the mixed solution comprises the following components in percentage by weight: 50-95% of ethanol, 1-25% of 1,4-dioxane and 1-25% of water; preferably, the mixed solution comprises the following components in percentage by weight: 50-90% of ethanol, 1-20% of 1,4-dioxane and 1-20% of water.

In the technical scheme of the invention, the operation pressure of the top of the reactive distillation tower is 0.20-1.20 MPaA, the operation temperature of the top of the tower is 95-160 ℃, the operation pressure of the bottom of the tower is 0.20-1.20 MPaA, the operation temperature of the bottom of the tower is 200-310 ℃, and the reflux ratio is 1-10; the operation pressure at the top of the tower is preferably 0.20-0.70 MPaA, the operation temperature at the top of the tower is preferably 95-140 ℃, the operation pressure at the bottom of the tower is preferably 0.20-0.71 MPaA, the operation temperature at the bottom of the tower is preferably 210-280 ℃, and the reflux ratio is preferably 2.5-10.

In the technical scheme of the invention, the operating pressure of the ethanol recovery tower is 0.20-1.0 MPaA, and the temperature of the top of the tower is 35-160 ℃; preferably, the operation pressure is 0.20-0.70 MPaA, and the tower top temperature is 35-140 ℃.

In the technical scheme of the invention, the reaction section of the reaction rectifying tower is provided with 10-30 theoretical plates.

In the technical scheme of the invention, the rectifying section of the reactive rectifying tower is provided with 10-30 theoretical plates.

In the technical scheme of the invention, the stripping section of the reactive distillation tower is provided with 10-30 theoretical plates.

In the technical scheme of the invention, the ethanol recovery tower is provided with 20-100 theoretical plates, and preferably 20-80 theoretical plates.

The inventor finds that the reaction and the separation process are combined through experiments, and the method has the advantages of simple process flow, low equipment investment and operation cost and the like.

The inventor finds through experiments that 1,4-dioxane and ethanol form an azeotrope in an ethanol recovery tower under normal pressure and reduced pressure. Pressure 101.3KPaA, azeotropic composition 1, 4-dioxane: ethanol is 5.1:94.9mole percent, and the azeotropic point temperature is 78.13 ℃; the azeotropic phenomenon disappears when the pressure exceeds 0.181 MPaA.

The invention changes the azeotropic composition between 1,4-dioxane and ethanol by increasing the operating pressure of the ethanol recovery tower, and achieves the aim of eliminating the azeotropy of 1,4-dioxane and ethanol when reaching a certain pressure.

Drawings

FIG. 1 is a schematic process flow diagram of the present invention.

In FIG. 1, C is an ethanol recovery tower, and D is a reaction rectification tower; 1 is the mixed solution, 2 is an ethylene oxide stream, 3 is a crude ethanol stream, 4 is an ethylene glycol stream, 5 is an ethanol stream, and 6 is a 1,4-dioxane stream.

In FIG. 1, a mixed solution stream (1) containing water, ethanol and 1,4-dioxane and an ethylene oxide stream (2) containing ethylene oxide are fed into a reactive distillation column D, and contacted under conditions suitable for the reaction of ethylene oxide with water, and separated by reaction to obtain a crude ethanol stream (3) containing ethanol and 1,4-dioxane and an ethylene glycol stream (4), and the crude ethanol stream (3) containing ethanol and 1,4-dioxane is fed into a second separation column C to obtain an ethanol stream (5) and a 1,4-dioxane stream (6).

The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention in any way.

Detailed Description

[ example 1 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 80 wt% of ethanol, 15 wt% of 1,4-dioxane, 5 wt% of water and 122.27kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.21MPaA, the temperature of the top of the tower is 98 ℃, the pressure of the bottom of the tower is 0.22MPaA, the temperature of the bottom of the tower is 225 ℃, and the load of the bottom of the tower is 503 kW.

The number of tower plates of the ethanol recovery tower is 95, the operating pressure is 0.20MPaA, the temperature at the top of the tower is 97 ℃, and the load at the bottom of the tower is 5.94 MW.

The purity of the ethanol product is 99.60 wt%, the recovery rate is 99.60%, the byproduct glycol is 172.27kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 2 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 80 wt% of ethanol, 15 wt% of 1,4-dioxane, 5 wt% of water and 122.27kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.30MPaA, the temperature of the top of the tower is 109 ℃, the pressure of the bottom of the tower is 0.31MPaA, the temperature of the bottom of the tower is 235 ℃, and the load of the bottom of the tower is 502 kW.

The number of tower plates of the ethanol recovery tower is 75, the operating pressure is 0.30MPaA, the temperature at the top of the tower is 109 ℃, and the load at the bottom of the tower is 5.13 MW.

The purity of the ethanol product is 99.87 wt%, the recovery rate is 99.87%, the byproduct glycol is 172.27kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 3 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 80 wt% of ethanol, 15 wt% of 1,4-dioxane, 5 wt% of water and 122.27kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.40MPaA, the temperature of the top of the tower is 118 ℃, the pressure of the bottom of the tower is 0.41MPaA, the temperature of the bottom of the tower is 251 ℃, and the load of the bottom of the tower is 472 kW.

The number of tower plates of the ethanol recovery tower is 75, the operating pressure is 0.40MPaA, the tower top temperature is 118 ℃, and the tower kettle load is 5.01 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 172.27kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 4 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 80 wt% of ethanol, 15 wt% of 1,4-dioxane, 5 wt% of water and 122.27kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.50MPaA, the temperature at the top of the tower is 126 ℃, the pressure at the bottom of the tower is 0.51MPaA, the temperature at the bottom of the tower is 261 ℃, and the load at the bottom of the tower is 500 kW.

The number of tower plates of the ethanol recovery tower is 75, the operating pressure is 0.50MPaA, the temperature at the top of the tower is 125 ℃, and the load at the bottom of the tower is 4.90 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 172.27kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 5 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 80 wt% of ethanol, 15 wt% of 1,4-dioxane, 5 wt% of water and 122.27kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.60MPaA, the tower top temperature is 132 ℃, the tower bottom pressure is 0.61MPaA, the tower bottom temperature is 269 ℃, and the tower bottom load is 519 kW.

The number of tower plates of the ethanol recovery tower is 55, the operating pressure is 0.60MPaA, the temperature at the top of the tower is 132 ℃, and the load of the tower kettle is 4.80 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 172.27kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 6 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 80 wt% of ethanol, 15 wt% of 1,4-dioxane, 5 wt% of water and 122.27kg/h of ethylene oxide.

The operation pressure of the reaction rectifying tower is 0.70MPaA, the temperature of the top of the tower is 138 ℃, the pressure of the bottom of the tower is 0.71MPaA, the temperature of the bottom of the tower is 276 ℃, and the load of the bottom of the tower is 546 kW.

The number of tower plates of the ethanol recovery tower is 30, the operating pressure is 0.70MPaA, the temperature at the top of the tower is 137 ℃, and the load at the bottom of the tower is 4.72 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 172.27kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 7 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 85 wt% of ethanol, 5 wt% of 1,4-dioxane, 10 wt% of water and 244.53kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.30MPaA, the temperature of the top of the tower is 109 ℃, the pressure of the bottom of the tower is 0.31MPaA, the temperature of the bottom of the tower is 238 ℃, and the load of the bottom of the tower is 480 kW.

The number of tower plates of the ethanol recovery tower is 80, the operating pressure is 0.30MPaA, the tower top temperature is 109 ℃, and the tower bottom load is 5.83 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 344.53kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 8 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 85 wt% of ethanol, 5 wt% of 1,4-dioxane, 10 wt% of water and 244.53kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.35MPaA, the temperature at the top of the tower is 114 ℃, the pressure at the bottom of the tower is 0.36MPaA, the temperature at the bottom of the tower is 244 ℃, and the load at the bottom of the tower is 465 kW.

The number of the tower plates of the ethanol recovery tower is 80, the operating pressure is 0.35MPaA, the temperature at the top of the tower is 114 ℃, and the load at the bottom of the tower is 5.75 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 344.53kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 9 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 85 wt% of ethanol, 5 wt% of 1,4-dioxane, 10 wt% of water and 244.53kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.45MPaA, the temperature of the top of the tower is 122 ℃, the pressure of the bottom of the tower is 0.46MPaA, the temperature of the bottom of the tower is 256 ℃, and the load of the bottom of the tower is 462 kW.

The number of tower plates of the ethanol recovery tower is 80, the operating pressure is 0.45MPaA, the tower top temperature is 122 ℃, and the tower bottom load is 5.63 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 344.53kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 10 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 65 wt% of ethanol, 20 wt% of 1,4-dioxane, 15 wt% of water and 366.80kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.30MPaA, the temperature of the top of the tower is 109 ℃, the pressure of the bottom of the tower is 0.31MPaA, the temperature of the bottom of the tower is 238 ℃, and the load of the bottom of the tower is 481 kW.

The number of tower plates of the ethanol recovery tower is 80, the operating pressure is 0.30MPaA, the temperature at the top of the tower is 109 ℃, and the load at the bottom of the tower is 4.46 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 516.80kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 11 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 65 wt% of ethanol, 20 wt% of 1,4-dioxane, 15 wt% of water and 366.80kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.50MPaA, the temperature at the top of the tower is 126 ℃, the pressure at the bottom of the tower is 0.51MPaA, the temperature at the bottom of the tower is 261 ℃, and the load at the bottom of the tower is 353 kW.

The number of tower plates of the ethanol recovery tower is 80, the operating pressure is 0.50MPaA, the temperature at the top of the tower is 125 ℃, and the load at the bottom of the tower is 4.26 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 516.80kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 12 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 65 wt% of ethanol, 20 wt% of 1,4-dioxane, 15 wt% of water and 366.80kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.70MPaA, the temperature of the top of the tower is 139 ℃, the pressure of the bottom of the tower is 0.71MPaA, the temperature of the bottom of the tower is 277 ℃, and the load of the bottom of the tower is 356 kW.

The number of tower plates of the ethanol recovery tower is 80, the operating pressure is 0.70MPaA, the temperature at the top of the tower is 137 ℃, and the load at the bottom of the tower is 4.10 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 516.80kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 13 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 60 wt% of ethanol, 20 wt% of 1,4-dioxane, 20 wt% of water and 489.06kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.30MPaA, the tower top temperature is 109 ℃, the tower bottom pressure is 0.31MPaA, the tower bottom temperature is 238 ℃, and the tower bottom load is 428 kW.

The number of tower plates of the ethanol recovery tower is 80, the operating pressure is 0.30MPaA, the temperature at the top of the tower is 109 ℃, and the load at the bottom of the tower is 4.12 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 689.06kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 14 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 60 wt% of ethanol, 20 wt% of 1,4-dioxane, 20 wt% of water and 489.06kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.40MPaA, the temperature at the top of the tower is 119 ℃, the pressure at the bottom of the tower is 0.41MPaA, the temperature at the bottom of the tower is 250 ℃, and the load at the bottom of the tower is 272 kW.

The number of tower plates of the ethanol recovery tower is 80, the operating pressure is 0.40MPaA, the tower top temperature is 118 ℃, and the tower kettle load is 4.02 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 689.06kg/h, and the purity of the byproduct glycol is 99.99%.

[ example 15 ]

According to the scheme shown in FIG. 1, the mixed solution is fed for 1000kg/h, the mixed solution comprises 60 wt% of ethanol, 20 wt% of 1,4-dioxane, 20 wt% of water and 489.06kg/h of ethylene oxide.

The operation pressure of the reactive distillation tower is 0.50MPaA, the temperature of the top of the tower is 126 ℃, the pressure of the bottom of the tower is 0.51MPaA, the temperature of the bottom of the tower is 261 ℃, and the load of the bottom of the tower is 276 kW.

The number of tower plates of the ethanol recovery tower is 80, the operating pressure is 0.50MPaA, the temperature at the top of the tower is 125 ℃, and the load at the bottom of the tower is 3.93 MW.

The purity of the ethanol product is 99.99 wt%, the recovery rate is 99.99%, the byproduct glycol is 689.06kg/h, and the purity of the byproduct glycol is 99.99%.