CN109734232B - Method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater - Google Patents
Method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater Download PDFInfo
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Abstract
The invention aims to provide a method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater, wherein the method mainly comprises the steps of pretreating the Fischer-Tropsch synthesis wastewater and then using electrodialysis and rectification in combination to obtain alcohol and dealcoholized water with the carbon number of below 4. The method is environment-friendly and can greatly reduce the energy consumption in the separation process.
Description
Technical Field
The invention relates to the field of wastewater treatment, in particular to a method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater.
Background
The Fischer-Tropsch synthesis reaction involves the conversion of carbonaceous resources such as coal, natural gas, biomass, organic waste and sludge into synthesis gas (CO and H)2) Then the organic matter is converted into hydrocarbon organic matter (mainly comprising normal paraffin, a small amount of isoparaffin, olefin and the like) through a specific catalyst, and simultaneously, a large amount of wastewater and part of low-carbon oxygen-containing organic matter (mainly comprising alcohol, aldehyde, ketone, acid, ester and the like) are generated, and a large amount of heat is released along with the generation of the organic matter. In the process of the iron-based Fischer-Tropsch synthesis reaction, the yield of the wastewater is generally more than one time of that of the synthesized oil product.
The water produced by the reaction and the hydrocarbon products obtained by Fischer-Tropsch synthesis can be conveniently separated, and this preliminary separation can comprise: the gas phase product of the Fischer-Tropsch reactor is cooled and flashed, a part of the gas phase product is cooled into liquid phase fluid, the liquid phase fluid is separated into water phase fluid containing a small amount of dissolved organic matters (hydrocarbon and oxygen-containing organic matters) and a small amount of suspended matters through an oil-water separator, and the water phase fluid is separated into water-rich fluid through a synthesis water filter, namely the Fischer-Tropsch synthesis wastewater to be treated. If the water and the oxygen-containing compounds in the oil can be separated and recycled, the economy of the Fischer-Tropsch synthesis process can be effectively improved, the environment-friendly treatment load of the water phase is reduced, the water recycling is realized, and the clean production can be realized in the coal-to-oil process.
In the Fischer-Tropsch synthesis process, the compositions of the generated Fischer-Tropsch synthesis water phase byproducts are different due to the use of different Fischer-Tropsch synthesis process technologies, Fischer-Tropsch synthesis catalysts or synthesis reaction operating parameters. Generally, the water content of the aqueous phase byproduct of the Fischer-Tropsch synthesis is 70 wt% -97 wt%, and the content of the organic oxygen-containing organic compound is 3 wt% -30 wt%. For example, the applicant established a coal-to-liquid demonstration plant of 16 ten thousand tons/year in inner mongolia and outer asian and ann coal-to-liquid companies respectively by using the high-temperature slurry bed iron-based fischer-tropsch synthesis technology of the chinese oil technology ltd, and successfully operated in 2009. According to the data of Fischer-Tropsch synthesis wastewater provided by a demonstration plant, the carbon number of the oxygen-containing organic matters is generally less than 8, and the content is generally less than 10 wt%. The oxygen-containing organic substance contained about 2 wt% of alcohols (mainly methanol, ethanol, propanol, butanol and pentanol), about 0.76 wt% of acids (mainly acetic acid, propionic acid, butyric acid and pentanoic acid), about 0.14 wt% of aldehydes (mainly acetaldehyde and propionaldehyde), about 0.07 wt% of ketones (mainly acetone) and about 0.02 wt% of esters (mainly ethyl acetate). In addition, the Fischer-Tropsch synthesis wastewater also contains dozens of oxygen-containing organic matters with the content lower than 50ppm, so that the influence on the Fischer-Tropsch synthesis wastewater treatment process is extremely small and can be avoided.
Due to the existence of hydrocarbon and oxygen-containing organic matters, the Fischer-Tropsch synthesis wastewater cannot be directly discharged and can not be recycled as circulating water, particularly, the Fischer-Tropsch synthesis wastewater cannot meet the discharge or recycling standard due to the existence of organic oxygen-containing compounds, and acid organic matters in the Fischer-Tropsch synthesis wastewater can corrode equipment. The Fischer-Tropsch synthesis related process flows (coal water slurry preparation, water gas shift, circulating water cooling and the like) need to consume a large amount of water resources, and the water resources in the Fischer-Tropsch synthesis water are recovered to be supplied to the related process flows through purification treatment of the Fischer-Tropsch synthesis water, so that the pollution to the environment can be reduced on one hand; on the other hand, organic matters with high added value in the Fischer-Tropsch synthesis water can be recovered, so that the purification treatment of the Fischer-Tropsch synthesis water is very necessary.
Chinese patents ZL03814122.1, ZL03814125.6 and ZL03814127.2 respectively disclose Fischer-Tropsch reaction water purification methods. The main process operating units involved in the patent include: common rectification, evaporation, extraction, biological treatment, solid-liquid separation, reverse osmosis and the like. In the process, firstly biological treatment is carried out on the water-containing substances at the bottom of the rectifying tower, and then reverse osmosis is carried out to obtain high-purity water, ZL201080018494.6 also discloses a similar method, and as the Fischer-Tropsch reaction water contains carboxylic acid organic substances, the rectifying tower equipment for separating the non-acid oxygen-containing organic substances in the patent needs to adopt corrosion-resistant materials, so that the investment cost is greatly increased, and alkaline substances are required to be added in a biological treatment operation unit to adjust the pH value.
Chinese patent application CN201010512405.5 discloses a method for separating and recovering organic oxygen-containing compounds in a Fischer-Tropsch synthesis water phase. The main operating units involved in the patent include: ordinary rectification, azeotropic rectification, extractive rectification, batch rectification, and the like. Mainly separate the recovery to single oxygen-containing organic matter in the ft synthetic aquatic, design 12 rectifying columns, the process is comparatively complicated to it is higher to the content requirement of oxygen-containing organic matter in the ft synthetic aquatic, and the separation condition is comparatively harsh, is not very suitable for the industrial production who uses the ft synthetic aqueous phase of purification recovery as the target, and the rectifying process power consumption is great moreover, makes operating cost increase.
Therefore, there is a need to develop a process that is relatively low in energy consumption, has a good cost-benefit ratio, and is capable of simultaneously recovering water and alcohol from fischer-tropsch synthesis wastewater.
Disclosure of Invention
In view of the above technical problems, the present invention aims to provide a method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater. The method of the invention adopts electrodialysis to separate the alkyd organic matters in the Fischer-Tropsch synthesis water, and further separates the alcohol and water with the carbon number of below 4 through rectification, thus being environment-friendly and greatly reducing the energy consumption for separation.
The invention provides a method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater, wherein the method comprises the following steps:
(1) carrying out pretreatment of oil removal, pH value adjustment by adding alkali and filtration on Fischer-Tropsch synthesis wastewater to obtain carboxylate-containing synthesis wastewater;
(2) performing brine separation on the synthetic wastewater containing the carboxylate by adopting electrodialysis to obtain alcohol-containing water and carboxylate concentrated solution with carboxylate removed;
(3) and (3) sending the alcohol-containing water with the carboxylate removed to a first rectifying tower for rectifying treatment to obtain alcohol with the alcohol content of below C4 and dealcoholized water.
The invention has the following characteristics:
(1) the method of the invention combines Electrodialysis (ED) and a rectifying tower to treat the Fischer-Tropsch synthesis wastewater, firstly adopts electrodialysis, so that alcohol with the carbon number below C4 can be separated out by rectification on the premise of reducing energy consumption, and simultaneously, water is primarily separated, and can be reused in the Fischer-Tropsch synthesis process by further treatment, such as application to circulating cooling, gasification chilling, gasification coal water slurry preparation, water gas shift and the like;
(2) the method can recover water in the Fischer-Tropsch synthesis wastewater, simultaneously recover the alcohol with the carbon number of below 4 in the water phase to the maximum extent, and directly separate the alcohol with the carbon number of below 4 by the treatment of the rectifying tower; the recovered alcohol can be further separated into single components or sold as industrial products or fine chemicals, thereby realizing the Fischer-Tropsch synthesis wastewater treatment technology with near zero discharge.
Drawings
FIG. 1 is a schematic view schematically showing a process for simultaneously recovering water and alcohols from Fischer-Tropsch synthesis wastewater.
In the drawings, the respective reference numerals denote the following: 101-Fischer-Tropsch synthesis wastewater; 102-synthetic wastewater containing carboxylate; 103-carboxylate-removing alcoholic water; 104-carboxylate concentrate; a stream of alcohol below 105-C4; 106-a stream of dealcoholated water; 107-alcohol-water mixed solution; 108-an extractant; 1-a pretreatment step; 2-electrodialysis step; 3-extractive distillation step; 4-atmospheric distillation step.
Detailed Description
The following exemplary embodiments are only for explaining the aspects of the present invention, and are not intended to limit the scope of protection of the present application in any way.
In the invention, unless otherwise stated, the Fischer-Tropsch synthesis wastewater can contain 1 wt% -15 wt% of oxygen-containing organic matters, wherein the oxygen-containing organic matters comprise C1-C8 alcohol, aldehyde, ketone, acid and/or ester organic compounds.
In the present invention, unless otherwise specified, the alcohol refers to a compound containing a hydroxyl group, including, but not limited to, methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, and/or octanol, and the like; the alcohol having not more than C4 means an alcohol having not more than 4 carbon atoms, such as methanol, ethanol, propanol and butanol; the alcohol having more than C4 is an alcohol having 4 or more than 4 (e.g., 5, 6, 7 or 8) carbon atoms, such as, but not limited to, pentanol (e.g., 2-pentanol or 3-methyl-1-butanol), hexanol (e.g., 2-hexanol), heptanol, and/or the like.
In the present invention, unless otherwise specified, the aldehyde-based organic compound means a compound having an aldehyde group, including, but not limited to, acetaldehyde, propionaldehyde and/or butyraldehyde, and the like.
In the present invention, unless otherwise specified, the ketone organic compound refers to a compound in which a carbonyl group is linked to two hydrocarbon groups, including, but not limited to, acetone, pentanone and/or hexanone, and the like.
In the present invention, unless otherwise specified, the ester-based organic compound refers to a compound produced by reacting an acid with an alcohol, including, but not limited to, methyl acetate, ethyl acetate, and/or butyrolactone, and the like.
In the present invention, unless otherwise specified, the acid-based organic compound means an organic compound having acidity, including, but not limited to, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, and/or isobutyric acid, and the like.
In one embodiment, the present invention relates to a process for the simultaneous recovery of water and alcohol from fischer-tropsch synthesis wastewater, wherein the process comprises the steps of:
(1) carrying out pretreatment of oil removal, pH value adjustment by adding alkali and filtration on Fischer-Tropsch synthesis wastewater to obtain carboxylate-containing synthesis wastewater;
(2) performing brine separation on the synthetic wastewater containing the carboxylate by adopting electrodialysis to obtain alcohol-containing water and carboxylate concentrated solution with carboxylate removed;
(3) and (3) sending the alcohol-containing water with the carboxylate removed to a first rectifying tower for rectifying treatment to obtain alcohol with the alcohol content of below C4 and dealcoholized water.
In the step (1), the oil removal is to remove petroleum organic matters (mainly hydrocarbon substances existing in a dissolving, emulsifying and dispersing state in the Fischer-Tropsch synthesis wastewater) in the Fischer-Tropsch synthesis wastewater; for example, the degreasing may be performed by any of fiber membrane filtration, coalescence, air flotation, ultrafiltration, and the like. The fiber membrane is a conventional commercially available fiber membrane that can be used for the removal of petroleum-based organics.
In a preferred embodiment, in the step (1), the oil removal is performed by using fiber membrane filtration, preferably, the filtration pressure difference of the fiber membrane filtration is not higher than 0.5 MPa; preferably, after the oil removal, the content of petroleum organic matters in the Fischer-Tropsch synthesis wastewater is not higher than 10 mg/L.
In a preferred embodiment, in the step (1) above, the base may be any one of an inorganic base, an organic base, or a basic substance; preferably, the inorganic base is selected from NaOH, KOH, Ca (OH)2And ammonia, preferably NaOH and/or Ca (OH)2. The alkaline substance may be the pH of an aqueous solution thereof>7 except for inorganic and organic bases.
In a preferred embodiment, in the step (1), the pH value may be adjusted by adding a base once or by adding a base multiple times, more preferably, the pH value is adjusted to 3 to 8, preferably 6 to 8, and still more preferably 6.5 to 7.
In a preferred embodiment, in step (1) above, the filtration is carried out using a filter element of 0.1 to 50 μm, preferably 1 to 50 μm, for example 1 to 10 μm, and preferably the filtration differential pressure is not higher than 0.3 MPa.
In the above step (2), the electrodialysis may be carried out using any conventional electrodialysis membranes known in the art; preferably, during the electrodialysis, the voltage is not more than 80V and the current is not more than 100A.
In a preferred embodiment, in the step (2), the concentrated solution of carboxylic acid salt may be further subjected to oxidation treatment, and the oxidation treatment may be performed by a biological oxidation method and/or an advanced oxidation method, for example, COD in water obtained after the oxidation treatment may be reduced to not more than 100mg/L, and optionally, the water obtained after the oxidation treatment may be further recycled.
In a preferred embodiment, in the step (3), before being sent to the first rectifying tower for rectification treatment, the alcohol-containing water from which the carboxylic acid salt is removed may be further concentrated.
In a preferred embodiment, in the step (3), before the alcohol-containing water from which the carboxylic acid salt is removed is sent to the first rectifying tower for rectification, the alcoholic water from which the carboxylic acid salt is removed is subjected to heat exchange and temperature rise, preferably, the heat exchange and temperature rise is 40 to 70 ℃.
In a preferred embodiment, in the step (3), the first rectification column is an extractive rectification column, and the alcohol-containing water from which the carboxylate is removed is sent to the extractive rectification column to be subjected to extractive rectification treatment under the action of an extractant, wherein an alcohol stream with a carbon number of below C4 is obtained at the top of the extractive rectification column, and a dealcoholized water stream is obtained at the bottom of the extractive rectification column. Preferably, the number of the plates of the extractive distillation column can be 45-80, preferably 48-68, and further preferably 50-65; the overhead temperature may be from 50 ℃ to 90 ℃, preferably from 65 ℃ to 75 ℃, for example from 70 ℃ to 75 ℃; the temperature of the tower kettle can be 70-200 ℃, preferably 85-120 ℃, and further preferably 95-110 ℃; the reflux ratio may be 0.1 to 10, preferably 7 to 9, and the recovery ratio is 0.005 to 0.5, preferably 0.007 to 0.01.
In the present invention, the term "reflux ratio" refers to the ratio of the top reflux rate to the withdrawn amount of the distillation column, unless otherwise specified.
In the present invention, the term "draw ratio" means a ratio of a draw amount to a feed amount from the top of a rectifying column, unless otherwise specified.
Herein, the dealcoholated water or dealcoholated water stream mainly comprises water, alcohol above C4 and an extractant.
In a further preferred embodiment, in step (3) above, the extractant is selected from a polar organic solvent, an ionic liquid and/or a solid salt. In a preferred embodiment, the polar organic solvent is selected from ethylene glycol and/or glycerol, preferably ethylene glycol; preferably, the ionic liquid is selected from 1, 3-dimethylimidazolium acetate, 1-ethyl-3-methylimidazolium acetate and/or 1-butyl-3-methylimidazolium tetrafluoroborate; preferably, the solid salt is selected from CaCl2NaCl, KCl, NaAc and/or KAc. Preferably, the mass ratio of the extracting agent to the alcohol-containing water for removing the carboxylate is 1 (0.01-10), preferably 1 (1-8).
In a preferred embodiment, the above method according to the present invention further comprises sending the dealcoholized water to a second rectification column for further rectification treatment, thereby obtaining an alcohol-water mixed solution (comprising water and alcohol with C4 or more) and an extractant. The rectification treatment of the above-mentioned step (3) and the rectification treatment of the additional step taken together may be a multi-stage rectification treatment, for example, a two-stage rectification treatment.
In a further preferred embodiment, the dealcoholized water is sent to a second rectification column to be further subjected to a normal rectification treatment, for example, the normal rectification treatment may be any one selected from a pressure rectification treatment, a vacuum rectification treatment and/or an atmospheric rectification treatment, preferably an atmospheric rectification treatment. Preferably, the additional rectification column can be selected from a pressurized rectification column, a vacuum rectification column and an atmospheric rectification column, preferably, the second rectification column is an atmospheric rectification column, and the number of plates of the atmospheric rectification column can be 20-40, preferably 20-30, and further preferably 22-25; the temperature at the top of the column may be 75 to 110 ℃, preferably 80 to 100 ℃, further preferably 90 to 100 ℃, for example 95 to 100 ℃; the temperature of the tower kettle can be 95-220 ℃, preferably 150-210 ℃ and further preferably 195-200 ℃; the reflux ratio may be 0.1 to 10, preferably 0.3 to 5, and more preferably 0.3 to 2, and the recovery ratio is 0.1 to 0.95, preferably 0.5 to 0.9.
In a more preferred embodiment, since the alcohol having a carbon number of C4 or more and water are immiscible with each other at room temperature, the alcohol-water mixture can be separated by a layer separator to obtain water and the alcohol having a carbon number of C4 or more.
In a further preferred embodiment, the extractant obtained in the column bottom of the further rectification column can be recycled to the extractive rectification column.
In the present invention, the term "ordinary temperature" may also be referred to as room temperature, and means a temperature of 15 ℃ to 30 ℃, unless otherwise specified.
Examples
The present invention will be described below with reference to specific examples, but the present invention is not limited thereto.
The experimental methods used in the following examples are all conventional methods unless otherwise specified; reagents, materials and the like used in the following examples are commercially available unless otherwise specified.
Example 1
Purifying and recycling Fischer-Tropsch synthetic wastewater according to the flow shown in figure 1, supplying 30000kg/h of purified and recycled Fischer-Tropsch synthetic wastewater 101, performing oil removal pretreatment under the normal temperature condition, filtering by using a fiber membrane in the oil removal process, wherein the filtering pressure difference is not higher than 0.5MPa, the petroleum organic matter content in the deoiled Fischer-Tropsch synthetic wastewater is not higher than 10mg/L, adding 119kg of NaOH to adjust the pH value after oil removal, filtering by using a filter element with the diameter of 50 mu m, and the filtering pressure difference is not higher than 0.3MPa to obtain 30119kg/h of carboxylate-containing synthetic wastewater 102 with the pH value of 6.5.
Performing concentration and separation on the carboxylate-containing synthetic wastewater 102 through an electrodialysis membrane in an electrodialysis step 2; the voltage of the electrodialysis was controlled not to exceed 80V and the current was controlled not to exceed 100A, yielding 24773kg/h of the alcohol-containing water 103 with carboxylate removal and 5346kg/h of the carboxylate concentrate 104.
The alcohol-containing water 103 without the carboxylate is heated to 70 ℃ through heat exchange, enters an extraction and rectification tower 3 for extraction and rectification treatment, the number of tower plates of the extraction and rectification tower is 65, the top temperature of the extraction and rectification tower is 65-75 ℃, the bottom temperature of the extraction and rectification tower is 95-110 ℃, the reflux ratio is 8, the extraction ratio is 0.007, the mass ratio of an extractant glycol to the alcohol-containing water 103 without the carboxylate is 1:1, a distillate (namely, a stream 105 of alcohol below 347kg/h C4) is obtained at the top of the extraction and rectification tower under the action of the extractant, and a stream 106 of dealcoholized water with the volume of 49199kg/h is obtained at the bottom of the extraction and rectification tower.
Further sending the dealcoholized stream 106 obtained at the bottom of the extractive distillation column 3 to an atmospheric distillation column, treating the dealcoholized stream by an atmospheric distillation step 4, wherein the number of plates of the atmospheric distillation column is 22, the temperature at the top of the column is 90-100 ℃, the temperature at the bottom of the column is 195-200 ℃, the reflux ratio is 2, the extraction ratio is 0.5, separating water in the dealcoholized stream 106 and alcohol above C4 from the top of the atmospheric distillation column to obtain 24600kg/h of alcohol-water mixed solution 107, and further separating the alcohol-water mixed solution 107 into alcohol above C4 and water by a delayer at normal temperature because the alcohol above C4 and the water are not mutually soluble; 24600kg/h of extractant ethylene glycol 108 obtained from the tower bottom of the atmospheric distillation tower is further sent to the extraction distillation tower 3 for recycling.
Table 1 analysis results (mass fraction) of main components of each stream in the process of example 1
From the data in table 1, it can be seen that: after carboxylate is removed by adopting the method of the invention, the alcohol component with water content not higher than 1 wt% and less than C4 is obtained by dehydration treatment through a rectifying tower. Meanwhile, the obtained dealcoholized water is further rectified to obtain process reuse water, and the obtained extracting agent is returned to the extraction rectifying tower for secondary utilization.
Example 2
Purifying and recycling Fischer-Tropsch synthesis water according to the flow shown in figure 1, supplying 30000kg/h of purified and recycled Fischer-Tropsch synthesis wastewater 101, performing oil removal pretreatment under the normal temperature condition, filtering by using a fiber membrane in the oil removal process, wherein the filtering pressure difference is not higher than 0.5MPa, the petroleum organic matter content in the Fischer-Tropsch synthesis wastewater after oil removal is not higher than 10mg/L, adding 130kg of NaOH after oil removal to adjust the pH value, filtering by using a filter element with the diameter of 1 mu m, and the filtering pressure difference is not higher than 0.3MPa to obtain 30130kg/h of carboxylate-containing synthesis wastewater 102 with the pH value of 7.
Performing concentration and separation on the carboxylate-containing synthetic wastewater 102 through an electrodialysis membrane in an electrodialysis step 2; the voltage of the electrodialysis is controlled not to exceed 80V, and the current is controlled not to exceed 100A, so that 16773kg/h of alcohol-containing water 103 for removing carboxylate and 13357kg/h of carboxylate concentrated solution 104 are obtained.
The alcohol-containing water 103 without the carboxylate is heated to 50 ℃ through heat exchange, enters an extraction and rectification tower 3 for extraction and rectification treatment, the number of plates of the extraction and rectification tower is 50, the top temperature of the extraction and rectification tower is 70-75 ℃, the bottom temperature of the extraction and rectification tower is 96-102 ℃, the reflux ratio is 8, the extraction ratio is 0.01, the mass ratio of an extractant glycol to the alcohol-containing water 103 without the carboxylate is 1:8, a distillate (namely, a stream 105 of alcohol below 190kg/h C4) is obtained at the top of the extraction and rectification tower under the action of the extractant, and a stream 106 of 18679kg/h dealcoholized water is obtained at the bottom of the extraction and rectification tower.
And (3) further sending the dealcoholized water stream 106 obtained at the bottom of the extraction and rectification tower 3 to an atmospheric rectification tower to be treated by an atmospheric rectification step 4, wherein the number of tower plates of the atmospheric rectification tower is 25, the tower top temperature is 95-100 ℃, the tower bottom temperature is 195-200 ℃, the reflux ratio is 0.3, and the extraction ratio is 0.9. Separating water and alcohol with the carbon number of more than 4 in the dealcoholized stream 106 from the top of the atmospheric distillation tower to obtain alcohol-water mixed solution 107 with the carbon number of 169904 kg/h, and further separating the alcohol-water mixed solution 107 into alcohol with the carbon number of more than 4 and water by adopting a delayer because the alcohol with the carbon number of more than 4 and the water are not mutually soluble at normal temperature; 1878kg/h of extractant ethylene glycol 108 obtained from the tower bottom of the atmospheric distillation tower is further sent to the extraction distillation tower 3 for recycling.
Table 2 main component analysis results (mass fraction) of each stream in the process of example 2
From the data in table 2, it can be seen that: after carboxylate is removed by adopting the method of the invention, the alcohol component with water content not higher than 1 wt% and less than C4 is obtained by dehydration treatment through a rectifying tower. Meanwhile, the obtained water can be directly recycled after further rectification treatment, and the extracting agent is also returned to the extraction and rectification tower for secondary utilization.
Claims (43)
1. A process for the simultaneous recovery of water and alcohol from fischer-tropsch synthesis wastewater, wherein the process comprises the steps of:
(1) carrying out pretreatment of oil removal, pH value adjustment by adding alkali and filtration on Fischer-Tropsch synthesis wastewater to obtain carboxylate-containing synthesis wastewater;
(2) performing brine separation on the synthetic wastewater containing the carboxylate by adopting electrodialysis to obtain alcohol-containing water and carboxylate concentrated solution with carboxylate removed;
(3) sending the water containing alcohol with the carboxylate removed to a first rectifying tower for rectifying treatment to obtain alcohol and dealcoholized water with the alcohol content of below C4;
and the method also comprises the step of sending the dealcoholized water to a second rectifying tower for further rectification treatment so as to obtain an alcohol-water mixed solution and an extracting agent, and separating the alcohol-water mixed solution by adopting a delayer so as to obtain water and alcohol with the carbon number of more than 4.
2. The method for simultaneously recovering water and alcohol from waste water of Fischer-Tropsch synthesis as claimed in claim 1, wherein in the step (1), the oil removal is performed by using fiber membrane filtration.
3. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater according to claim 2, wherein the filtration pressure difference of the fiber membrane filtration is not higher than 0.5 MPa.
4. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater according to any one of claims 1-3, wherein after the oil removal, the content of petroleum-based organic matters in the Fischer-Tropsch synthesis wastewater is not higher than 10 mg/L.
5. The process for simultaneous recovery of water and alcohol from Fischer-Tropsch synthesis wastewater according to any one of claims 1 to 3, wherein in step (1), the base is any one of an inorganic base or an organic base.
6. The method for simultaneously recovering water and alcohol from waste water of Fischer-Tropsch synthesis as claimed in claim 5, wherein the inorganic base is selected from NaOH, KOH, Ca (OH)2And ammonia water.
7. The method for simultaneously recovering water and alcohol from wastewater of Fischer-Tropsch synthesis as claimed in claim 6, wherein the inorganic base is NaOH and Ca (OH)2At least one of (1).
8. The process for simultaneous recovery of water and alcohol from Fischer-Tropsch synthesis wastewater according to any one of claims 1 to 3, wherein in step (1), the pH is adjusted by adding base once or by adding base several times in stages.
9. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater according to claim 8, wherein the pH is adjusted to 3 to 8.
10. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater according to claim 9, wherein the pH is adjusted to 6 to 8.
11. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater according to claim 10, wherein the pH is adjusted to 6.5 to 7.
12. A process for the simultaneous recovery of water and alcohol from waste water of Fischer-Tropsch synthesis as claimed in any one of claims 1 to 3, wherein in step (1), said filtration is carried out using a filter element of 0.1 to 50 μm.
13. A process for the simultaneous recovery of water and alcohol from waste water of Fischer-Tropsch synthesis as claimed in any one of claims 1 to 3, wherein in step (1), said filtration is carried out using a filter element of 1 to 50 μm.
14. The process for simultaneous recovery of water and alcohol from fischer-tropsch synthesis wastewater as claimed in claim 12, wherein the filtration pressure differential of the filtration is not higher than 0.3 MPa.
15. The process for simultaneously recovering water and alcohol from waste water of Fischer-Tropsch synthesis as claimed in any one of claims 1 to 3, wherein in the step (2), during the electrodialysis, the voltage is not more than 80V and the current is not more than 100A.
16. The process for simultaneous recovery of water and alcohol from Fischer-Tropsch synthesis wastewater as claimed in any one of claims 1 to 3, wherein in said step (2), said carboxylate salt concentrate is further subjected to an oxidation treatment, said oxidation treatment being carried out by at least one of a biological oxidation process and an advanced oxidation process.
17. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater of claim 16, wherein the water obtained after the oxidation treatment is recycled.
18. The method for simultaneously recovering water and alcohol from waste water of Fischer-Tropsch synthesis as claimed in any one of claims 1 to 3, wherein in the step (3), the carboxylate-removed alcoholic water is concentrated before being sent to the first rectifying tower for rectification treatment.
19. The method for simultaneously recovering water and alcohol from waste water of Fischer-Tropsch synthesis as claimed in any one of claims 1 to 3, wherein in the step (3), the alcohol-containing water from which the carboxylate is removed is subjected to heat exchange and temperature rise before being sent to the first rectifying tower for rectification treatment.
20. The process for simultaneous recovery of water and alcohol from fischer-tropsch synthesis wastewater as claimed in claim 19, wherein the carboxylate-depleted alcohol-containing water is heat exchanged at an elevated temperature of 40 ℃ to 70 ℃.
21. The method for simultaneously recovering water and alcohol from wastewater of Fischer-Tropsch synthesis as claimed in any one of claims 1-3, wherein in the step (3), the first rectification column is an extractive rectification column, and the carboxylate-removed water containing alcohol is sent to the extractive rectification column to be subjected to extractive rectification treatment under the action of an extracting agent, wherein the alcohol with C4 or less is obtained at the top of the extractive rectification column, and the dealcoholized water is obtained at the bottom of the extractive rectification column.
22. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater as claimed in claim 21, wherein the number of the plates of the extractive distillation column is 45-80; the temperature of the tower top is 50-90 ℃; the temperature of the tower kettle is 70-200 ℃; the reflux ratio is 0.1-10, and the extraction ratio is 0.005-0.5.
23. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater as claimed in claim 22, wherein the number of the plates of the extractive distillation column is 48-68; the temperature of the tower top is 65-75 ℃; the temperature of the tower kettle is 85-120 ℃.
24. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater according to claim 23, wherein the number of the plates of the extractive distillation column is 50-65; the temperature at the top of the tower is 70-75 ℃; the temperature of the tower kettle is 95-110 ℃.
25. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater as claimed in claim 22, wherein the reflux ratio is 7-9, and the recovery ratio is 0.007-0.01.
26. The process for simultaneously recovering water and alcohol from waste water of Fischer-Tropsch synthesis as claimed in claim 21, wherein in the step (3), the extractant is selected from at least one of polar organic solvent, ionic liquid and solid salt.
27. The process for simultaneous recovery of water and alcohol from fischer-tropsch synthesis wastewater as claimed in claim 26, wherein the polar organic solvent is selected from at least one of ethylene glycol and glycerol.
28. The process for simultaneous recovery of water and alcohol from fischer-tropsch synthesis wastewater as claimed in claim 27, wherein the polar organic solvent is ethylene glycol.
29. The process for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater of claim 26, wherein the ionic liquid is at least one selected from the group consisting of 1, 3-dimethylimidazolium acetate, 1-ethyl-3-methylimidazolium acetate, and 1-butyl-3-methylimidazolium tetrafluoroborate.
30. The process for simultaneous recovery of water and alcohol from fischer-tropsch synthesis wastewater as claimed in claim 26, wherein the solid salt is selected from CaCl2At least one of NaCl, KCl, NaAc and KAc.
31. The method for simultaneously recovering water and alcohol from the Fischer-Tropsch synthesis wastewater as claimed in claim 21, wherein the mass ratio of the extracting agent to the carboxylate-removed alcohol-containing water is 1 (0.01-10).
32. The method for simultaneously recovering water and alcohol from the Fischer-Tropsch synthesis wastewater as claimed in claim 31, wherein the mass ratio of the extracting agent to the carboxylate-removed alcohol-containing water is 1 (1-8).
33. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater as claimed in claim 1, wherein the method further comprises sending the dealcoholized water to a second rectifying tower for further ordinary rectification.
34. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater according to claim 33, wherein the normal rectification process is any one selected from a group consisting of a pressure rectification process, a vacuum rectification process and an atmospheric rectification process.
35. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater according to claim 34, wherein the normal distillation process is an atmospheric distillation process.
36. The method for simultaneously recovering water and alcohol from wastewater of Fischer-Tropsch synthesis according to claim 1, wherein said second distillation column is selected from the group consisting of a pressurized distillation column, a vacuum distillation column and an atmospheric distillation column.
37. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater as claimed in claim 36, wherein the second rectification column is an atmospheric rectification column, and the number of the plates of the atmospheric rectification column is 20-40; the temperature at the top of the tower is 75-110 ℃; the temperature of the tower kettle is 95-220 ℃; the reflux ratio is 0.1-10, and the extraction ratio is 0.1-0.95.
38. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater as claimed in claim 37, wherein the number of the plates of the atmospheric distillation tower is 20-30; the temperature of the tower top is 80-100 ℃; the temperature of the tower kettle is 150-210 ℃.
39. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater as claimed in claim 38, wherein the number of the plates of the atmospheric distillation tower is 22-25; the temperature of the tower top is 90-100 ℃; the temperature of the tower kettle is 195-200 ℃.
40. The method for simultaneously recovering water and alcohol from wastewater of Fischer-Tropsch synthesis according to claim 39, wherein the overhead temperature of said atmospheric distillation column is in the range of 95 ℃ to 100 ℃.
41. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater as claimed in claim 37, wherein the reflux ratio is 0.3-5, and the recovery ratio is 0.5-0.9.
42. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater as claimed in claim 41, wherein the reflux ratio is 0.3-2.
43. The method for simultaneously recovering water and alcohol from Fischer-Tropsch synthesis wastewater of claim 21, wherein the extractant is recycled to the extractive distillation column.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1662458A (en) * | 2002-06-18 | 2005-08-31 | Sasol技术股份有限公司 | Method of purifying fischer-tropsch derived water |
| CN101952205A (en) * | 2008-01-18 | 2011-01-19 | 艾尼股份公司 | Process for the treatment of the aqueous stream coming from the fischer-tropsch reaction |
| CN103435211A (en) * | 2013-08-22 | 2013-12-11 | 中科合成油技术有限公司 | Purification recovery method of Fischer-Tropsch synthesis water |
| CN103523986A (en) * | 2013-09-17 | 2014-01-22 | 中科合成油工程有限公司 | Treatment method of Fischer-Tropsch synthesis water |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1662458A (en) * | 2002-06-18 | 2005-08-31 | Sasol技术股份有限公司 | Method of purifying fischer-tropsch derived water |
| CN101952205A (en) * | 2008-01-18 | 2011-01-19 | 艾尼股份公司 | Process for the treatment of the aqueous stream coming from the fischer-tropsch reaction |
| CN103435211A (en) * | 2013-08-22 | 2013-12-11 | 中科合成油技术有限公司 | Purification recovery method of Fischer-Tropsch synthesis water |
| CN103523986A (en) * | 2013-09-17 | 2014-01-22 | 中科合成油工程有限公司 | Treatment method of Fischer-Tropsch synthesis water |
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