CN115340151B - Membrane extraction method for separating ethanol from ethanol high-salt wastewater - Google Patents
Membrane extraction method for separating ethanol from ethanol high-salt wastewater Download PDFInfo
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- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 title claims abstract description 246
- 239000002351 wastewater Substances 0.000 title claims abstract description 62
- 238000000034 method Methods 0.000 title claims abstract description 45
- 238000000409 membrane extraction Methods 0.000 title claims abstract description 20
- 239000012528 membrane Substances 0.000 claims abstract description 79
- 239000007788 liquid Substances 0.000 claims abstract description 62
- 150000003839 salts Chemical class 0.000 claims abstract description 22
- 230000002209 hydrophobic effect Effects 0.000 claims abstract description 17
- 239000002131 composite material Substances 0.000 claims abstract description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 15
- 239000000463 material Substances 0.000 claims abstract description 11
- -1 polytetrafluoroethylene Polymers 0.000 claims description 9
- 230000001105 regulatory effect Effects 0.000 claims description 9
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- 229920001343 polytetrafluoroethylene Polymers 0.000 claims description 3
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- 238000004065 wastewater treatment Methods 0.000 claims description 3
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- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 4
- 229910052799 carbon Inorganic materials 0.000 abstract description 3
- 239000013589 supplement Substances 0.000 abstract description 3
- 238000004064 recycling Methods 0.000 abstract description 2
- 238000000746 purification Methods 0.000 abstract 1
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 14
- 230000004907 flux Effects 0.000 description 13
- 239000002033 PVDF binder Substances 0.000 description 9
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 9
- 239000002121 nanofiber Substances 0.000 description 7
- 239000011780 sodium chloride Substances 0.000 description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 239000004205 dimethyl polysiloxane Substances 0.000 description 6
- 235000013870 dimethyl polysiloxane Nutrition 0.000 description 6
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 description 6
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- 239000011368 organic material Substances 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
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- 239000000047 product Substances 0.000 description 1
- HFHDHCJBZVLPGP-UHFFFAOYSA-N schardinger α-dextrin Chemical compound O1C(C(C2O)O)C(CO)OC2OC(C(C2O)O)C(CO)OC2OC(C(C2O)O)C(CO)OC2OC(C(O)C2O)C(CO)OC2OC(C(C2O)O)C(CO)OC2OC2C(O)C(O)C1OC2CO HFHDHCJBZVLPGP-UHFFFAOYSA-N 0.000 description 1
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Classifications
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
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- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
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- Organic Chemistry (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention discloses a self-driven low-energy-consumption membrane extraction method for separating ethanol from ethanol high-salt wastewater. In the membrane module, a hydrophobic and organophilic porous or thin-layer composite membrane material divides the module into two independent chambers, and wastewater containing high-concentration ethanol and salt enters one of the chambers in a cross-flow mode and circulates under the driving of a circulating pump from a feeding tank; in the other chamber, water is used as a receiving liquid, and circulated. The ethanol is driven by pressure difference caused by concentration difference and flow difference at two sides of the membrane to enter the receiving liquid step by step, and salt is completely intercepted by the hydrophobic membrane, so that the ethanol is efficiently separated and recovered. The method is simple to operate, only runs at low pressure/no pressure, and has lower energy consumption and higher separation purity compared with other separation modes. The ethanol solution separated by the method can be used for denitrification carbon source supplement and further purification and utilization in sewage treatment, so that the recycling rate of the sewage is effectively improved, and the method is simple and easy to implement.
Description
Technical Field
The invention relates to the technical field of ethanol wastewater reclamation, in particular to a self-driven low-energy-consumption membrane extraction method for separating ethanol from ethanol high-salt wastewater.
Background
Industrial production discharges a large amount of industrial wastewater containing high-concentration organic and inorganic pollutants at the same time, and valuable organic material sources are separated and extracted from the wastewater, so that the method is an important mode for recycling sewage, is beneficial to realizing high-value utilization of the wastewater, and can effectively reduce the difficulty and cost of subsequent wastewater treatment. Taking ethanol high-salt wastewater from industries such as food industry, medicine and health as an example, the ethanol high-salt wastewater contains a large amount of ethanol and inorganic salt, and has strong toxic action on microorganisms in biological treatment. In addition, ethanol is a valuable industrial feedstock, and is separated and recovered from wastewater with significant environmental and economic values.
The existing technology for recovering ethanol from ethanol high-salt wastewater mainly comprises a distillation method, a pervaporation method and the like. The distillation method is an operation method of evaporating ethanol and condensing and recovering the ethanol by precisely controlling the temperature by utilizing the difference in boiling point between ethanol and a solvent. Chinese patent (CN 202111074945) developed a device for recovering ethanol from ethanol waste liquid by distillation, the heating speed and heat loss in the distillation process are effectively improved, but high temperature is continuously provided in the separation process and matched with condensation operation, and serious scaling problem is faced when wastewater with excessive inorganic salt concentration is treated, and the process is complex and the occupied area is large. The pervaporation method makes the chemical potential of the feed liquid generate larger difference between the upstream and downstream of the membrane by artificially manufacturing vacuum or near vacuum conditions at the downstream of the membrane, and further realizes the selective separation technology by utilizing the difference of affinity and mass transfer resistance of the membrane to different components in the feed liquid. Chinese patent (CN 202110127875) developed a polydimethyl siloxane membrane material filled with a silica-coated graphene oxide nanocomposite material, which achieved high flux pervaporation of ethanol solution, but in order to maintain the chemical potential gradient of ethanol on both sides of the membrane, a vacuum receiving environment is usually continuously created on the permeate side, and a higher temperature is maintained on the feed side, which all require a lot of additional energy. Whether a large amount of stable heat source input is needed or a large amount of energy is consumed, the technologies are barriers to separating ethanol from ethanol high-salt wastewater.
Accordingly, those skilled in the art have been working to explore whether the separation of ethanol from ethanol high-salt wastewater can be achieved by utilizing the pressure difference caused by the concentration difference and the flow difference of ethanol at both sides of the membrane, and to develop a self-driven low-energy-consumption membrane extraction ethanol separation method. According to the invention, water is used as a receiving liquid, the pressure difference caused by the concentration difference and the flow difference of ethanol at two sides of the membrane is used as a driving force, and the difference of mass transfer performance of ethanol and salt in the hydrophobic and organophilic membrane is utilized to realize the separation of ethanol from ethanol high-salt wastewater. Compared with a distillation method relying on heat source driving and a pervaporation method relying on a continuous vacuum environment, a membrane extraction method using a pressure difference caused by a concentration difference and a flow difference of ethanol at two sides of a membrane as main driving forces is a greener technology with lower energy consumption.
Disclosure of Invention
In order to solve the defects of the existing ethanol separation technology, the invention provides a membrane extraction method for separating ethanol from ethanol high-salt wastewater. The method is environment-friendly, and overcomes the defects that the traditional separation method needs to consume a large amount of energy or extra chemical resources and the like. The system operation parameters, the film thickness and the film materials can be regulated and controlled, the ethanol separation rate and the complete interception of salt can be realized, the purity of the separation product is higher, and the method can be used for various purposes such as wastewater pretreatment, carbon source supplement of sewage plants and the like.
The invention provides a membrane extraction method for separating ethanol from ethanol high-salt wastewater, which comprises the following steps:
step 1, removing insoluble suspended matters from ethanol high-salt wastewater to be separated, introducing the wastewater into a feed tank, regulating the pH value of the wastewater to a proper range by using acid and alkali, regulating the temperature of the wastewater, and capping and stirring to uniformly mix the wastewater;
step 2, fixing a hydrophobic and organophilic porous membrane or a thin-layer composite membrane in a membrane assembly, dividing the membrane assembly into two independent chambers, connecting the membrane assembly and a feeding tank by using a pipeline, and respectively adding a circulating pump, a valve and a pressure gauge in the pipeline;
step 3, introducing receiving liquid into a receiving material liquid tank, adjusting the pH of the receiving liquid, and connecting with the membrane component in the same way;
step 4, regulating a circulating pump, setting the flow, the flow speed and the transmembrane pressure of the receiving liquid and the feeding liquid, and starting the circulating pump;
step 5, monitoring the conductivity of the receiving liquid in real time by using a conductivity meter, sampling and detecting the concentration of ethanol in the receiving liquid at fixed time, and determining the ending operation time according to the use requirement;
and 6, optionally determining whether to replace the membrane material, and starting the next operation by replacing the receiving liquid.
Further, the salt concentration range in the ethanol high-salt wastewater in the step is 0-50 g/L, the ethanol concentration range is 1-10 g/L, and the surface tension of the wastewater after insoluble matters are removed is more than 60mN/m (20 ℃).
Further, the pH range of the wastewater is 5-8, the temperature is 25+/-5 ℃, and the stirring rotation speed is 100-500 r/min.
Further, in the step 2, the water contact angle of the hydrophobic and organophilic porous or thin layer composite film is greater than 110 ° and the ethanol contact angle is less than 40 °.
Further, the aperture of the hydrophobic and organophilic porous membrane is 0.1-1 mu m, and the aperture of the thin-layer composite membrane is 0-0.1 mu m.
Further, the hydrophobic and organophilic porous membrane or thin layer composite membrane material is one or more of polyvinylidene fluoride, polypropylene, polyacrylonitrile, polytetrafluoroethylene, polymethyl methacrylate, polydimethylsiloxane and cyclodextrin.
Further, the hydrophobic and organophilic porous membrane is prepared by a phase inversion method or an electrostatic spinning method, and the hydrophobic and organophilic thin layer composite membrane is a composite of a nanofiber membrane and a thin layer membrane prepared by the electrostatic spinning method.
Further, the water flow mode in the membrane component is cross flow, and the effective membrane area is 20-100 cm 2 The component is made of stainless steel or polytetrafluoroethylene.
Further, the pH of the receiving liquid is 2-12, and the temperature is 15-35 ℃.
Further, the operating parameters are: the flow rate of the feed liquid and the receiving liquid is 0.1-10 cm/s, the flow rate is 0.1-50L/h, and the transmembrane hydraulic pressure is 0-20 kPa.
The membrane extraction method for separating ethanol from the ethanol high-salt wastewater is applied to the fields of wastewater treatment, wastewater reclamation and the like.
The technical scheme of the invention is as follows:
the species spontaneously diffuses from the high concentration region to the low concentration region until uniformly distributed, with a significant difference in diffusion rates of the different species in the same medium. The ethanol high-salt wastewater and the receiving liquid are separated by using the hydrophobic and organophilic permselective extraction membrane, and ethanol molecules and salt can diffuse to the receiving liquid side under the action of hydraulic pressure difference caused by flow difference because the concentration of ethanol and salt in the wastewater side is far higher than that in the receiving liquid side, but the hydrophobic and organophilic membrane can block the water to pass through so as to block the transmembrane of the salt, and ethanol can gradually enter the receiving liquid through the dissolving-diffusing process. Therefore, the method does not consume extra energy and chemical resources, and can realize the regulation and control of the ethanol separation efficiency.
The beneficial technical effects of the invention are as follows:
(1) The invention has simple realization method, does not need to use complex equipment, has stronger application range to temperature and pressure, has small occupied area and is easy to realize automatic control; can obtain better ethanol separation effect; continuous stable transmembrane and complete rejection of salts of ethanol can be achieved by regulating and controlling the permselective extraction membrane and operating parameters.
(2) The invention is green and energy-saving; no additional energy and chemical resources are consumed; the water is used as the receiving liquid, only the pressure difference caused by the concentration difference and the flow difference of the ethanol at the two sides of the membrane is used as the mass transfer driving force, the mass transfer efficiency of the ethanol is controllable, the problem of high cost in the prior ethanol separation process is solved, and the environment-friendly development concept is met.
(3) The method has wide applicability; ethanol can be extracted from high-salt wastewater of ethanol with different concentrations, and various water bodies such as surface water, tap water, secondary effluent of sewage plants and the like can be used as receiving liquid.
Drawings
FIG. 1 is a schematic view of an apparatus used in a preferred embodiment of the present invention; wherein 1 is a wastewater liquid storage tank, 2 is a circulating pump, 3 is a pressure gauge, 4 is a membrane material, 5 is a membrane component, 6 is a pipeline valve, and 7 is a receiving liquid storage tank.
FIG. 2 is a surface topography (SEM) and a surface Atomic Force Microscope (AFM) of a porous polyvinylidene fluoride nanofiber membrane used in a preferred embodiment of the invention;
FIG. 3 is a top and bottom surface topography (SEM) and a surface Atomic Force Microscope (AFM) of a thin layer composite film used in a preferred embodiment of the invention;
FIG. 4 shows the ethanol separation effect (ethanol transmembrane flux and salt rejection) achieved by a preferred embodiment of the present invention;
FIG. 5 shows the ethanol separation effect (ethanol transmembrane flux and salt rejection) achieved by a preferred embodiment of the present invention.
Detailed Description
The following description of the preferred embodiments of the present invention refers to the accompanying drawings, which make the technical contents thereof more clear and easy to understand. The present invention may be embodied in many different forms of embodiments and the scope of the present invention is not limited to only the embodiments described herein.
In the drawings, the size and thickness of each component shown are arbitrarily shown, and the present invention is not limited to the size and thickness of each component. The thickness of the components is exaggerated in some places in the drawings for clarity of illustration.
FIG. 1 is a schematic view of an apparatus used in a preferred embodiment of the present invention; fig. 2 is a surface topography (SEM) and a surface Atomic Force Microscope (AFM) of a porous polyvinylidene fluoride nanofiber membrane used in the method of the present invention, and fig. 3 is a top and bottom surface topography (SEM) and a surface Atomic Force Microscope (AFM) of a thin layer composite membrane used in the method of the present invention.
Example 1:
a membrane extraction method for separating ethanol from ethanol high-salt wastewater, comprising the following steps:
step 1, weighing ethanol and sodium chloride, dissolving in deionized water, stirring until the ethanol and the sodium chloride are completely dissolved, and preparing simulated ethanol high-salt wastewater with the ethanol concentration of 5 g/L and the sodium chloride concentration of 2 g/L; transferring the wastewater into a feed liquid tank, and uniformly stirring by using a magnetic stirrer at the rotating speed of 300 r/min; the simulated wastewater is adjusted to pH 7 by using 1M HCI and 1M NaOH, and the temperature is controlled at 25 ℃;
step 2, manufacturing a hydrophobic and organophilic porous nanofiber membrane by using an electrostatic spinning method; the prepared polyvinylidene fluoride hydrophobic and organophilic nanofiber membrane has a membrane thickness of 45 mu m and a membrane pore diameter of 0.68 mu m; the water contact angle of the membrane is 138 degrees, the ethanol contact angle is 0 degree, and the membrane is placed in a membrane assembly and connected with a liquid receiving tank;
step 3, using tap water as receiving liquid, adjusting the pH value of the receiving liquid to 7.5, and connecting the receiving liquid with the membrane component;
step 4, adjusting the flow rate and the flow velocity of the receiving liquid and the feeding liquid in the membrane assembly, and measuring the hydraulic transmembrane pressure at two sides of the membrane, wherein the specific parameters are shown in table 1;
step 5, monitoring conductivity change in the receiving liquid in real time, and calculating the retention rate of salt; sampling and detecting the concentration of ethanol in the receiving liquid at intervals, and calculating the ethanol flux; after 24 hours of operation, ending the operation;
and 6, replacing the wastewater and the receiving liquid, and starting the next separation operation.
FIG. 1 is a schematic view of a device used in this embodiment, and as can be seen from the figure, the method has a simple structure, a small occupied area and easy operation; fig. 2 is a surface topography (SEM) and a surface Atomic Force Microscopy (AFM) of the hydrophobic, organophilic nanofiber polyvinylidene fluoride membrane used in this example, with micron-sized pore sizes providing a large free volume for the ethanol molecules to cross the membrane, with a roughness large enough to make the membrane excellent in hydrophobicity, thus achieving complete rejection of salts. In addition, the strong affinity between ethanol and polyvinylidene fluoride allows ethanol to rapidly cross-membrane through a dissolution-diffusion process.
Sampling and detecting the conductivity change and the ethanol concentration of the receiving liquid in 1h, 3h, 6h, 12h and 24h respectively; FIG. 4 shows the calculated Ethanol flux (Ethanol flux, g m 2 h -1 ) And Salt rejection rate (percent), the calculation formula is as follows:
wherein V is r (L) is the volume of the receiving liquid, C r t (mg L -1 ) Is the ethanol concentration in the receiving liquid at time t (h), A (m 2 ) Is the effective area of the membrane material, C f，NaCI (mg L -1 ) And C r，NaCI (mg L -1 ) The concentration of sodium chloride in the wastewater and the receiving liquid, respectively. The left side bar graph shows the ethanol flux under different pressure conditions, the right side bar graph shows the salt rejection rate, and the system can realize 100% salt rejection rate under the hydraulic transmembrane pressure of 0-9kPa, and meanwhile, the ethanol flux is increased along with the increase of the hydraulic pressure; at 9kPa, the ethanol transmembrane flux was 34.7g m 2 h -1 The method comprises the steps of carrying out a first treatment on the surface of the After 24 hours, the conductivity of the receiving liquid still keeps the initial level, the concentration of the ethanol is higher, and the method can be used for carbon source supplement and other purposes of a sewage plant.
TABLE 1 transmembrane pressure during operation, flow rates and flow rates of feed and receiving solutions
Example 2:
a membrane extraction method for separating ethanol from ethanol high-salt wastewater, comprising the following steps:
step 1, weighing ethanol and sodium chloride, dissolving in deionized water, stirring until the ethanol and the sodium chloride are completely dissolved, and preparing simulated ethanol high-salt wastewater with the ethanol concentration of 5 g/L and the sodium chloride concentration of 10 g/L; transferring the wastewater into a feed liquid tank, and uniformly stirring by using a magnetic stirrer at the rotating speed of 300 r/min; the simulated wastewater is adjusted to pH 8 by using 1M HCI and 1M NaOH, and the temperature is controlled at 30 ℃;
step 2, a thin layer composite membrane formed by compositing a polyvinylidene fluoride nanofiber membrane and a polydimethylsiloxane thin layer is used; the total thickness of the prepared thin-layer composite membrane is 45 mu m, the thickness of the polydimethylsiloxane layer is 5 mu m, and the pore diameter of the membrane is 25nm; the water contact angle of the top surface (polyvinylidene fluoride side) of the membrane is 138 degrees, the ethanol contact angle is 0 degree, the water contact angle of the bottom surface (polydimethylsiloxane side) is 116 degrees, the ethanol contact angle is 36 degrees, and the membrane is placed in a membrane assembly and connected with a liquid receiving tank;
step 3, natural river water is used as receiving liquid, the pH value of the receiving liquid is regulated to 6, and the receiving liquid is connected with the membrane component;
step 4, adjusting the flow rate and the flow velocity of the receiving liquid and the feeding liquid in the membrane assembly, and measuring the hydraulic transmembrane pressure at two sides of the membrane, wherein the specific parameters are shown in table 1;
step 5, monitoring conductivity change in the receiving liquid in real time, and calculating the retention rate of salt; sampling and detecting the concentration of ethanol in the receiving liquid at intervals, and calculating the ethanol flux; after 24 hours of operation, ending the operation;
and 6, replacing the wastewater and the receiving liquid, and starting the next separation operation.
FIG. 3 is a top and bottom surface topography (SEM) and a surface Atomic Force Microscope (AFM) of the thin layer composite membrane used in this example, where polyvinylidene fluoride provided sufficiently large pore size and hydrophobicity; at the bottom, a relatively dense polydimethylsiloxane layer ensures excellent salt rejection properties of the membrane.
Sampling and detecting receiving liquid at 1h, 3h, 6h, 12h and 24h respectivelyConductivity change and ethanol concentration of (a); FIG. 5 is a graph of calculated ethanol flux and salt rejection; the left bar graph shows ethanol flux under different pressure conditions, the right bar graph shows salt rejection rate, and the graph shows that the ethanol transmembrane flux is 6.12g m under 9kPa 2 h -1 After 24 hours, the conductivity of the receiving solution remained at the initial level, with 100% salt rejection.
The foregoing describes in detail preferred embodiments of the present invention. It should be understood that numerous modifications and variations can be made in accordance with the concepts of the invention without requiring creative effort by one of ordinary skill in the art. Therefore, all technical solutions which can be obtained by logic analysis, reasoning or limited experiments based on the prior art by the person skilled in the art according to the inventive concept shall be within the scope of protection defined by the claims.
Claims (9)
1. A membrane extraction method for separating ethanol from ethanol high-salt wastewater, which is characterized by comprising the following steps:
step 1, removing insoluble suspended matters from ethanol high-salt wastewater to be separated, introducing the wastewater into a feed tank, regulating the pH value of the wastewater to a proper range by using acid and alkali, regulating the temperature of the wastewater, and capping and stirring to uniformly mix the wastewater;
step 2, fixing a hydrophobic and organophilic porous membrane or a thin-layer composite membrane in a membrane assembly, dividing the membrane assembly into two independent chambers, connecting the membrane assembly and a feeding tank by using a pipeline, and respectively adding a circulating pump, a valve and a pressure gauge in the pipeline;
step 3, introducing receiving liquid into a receiving material liquid tank, adjusting the pH of the receiving liquid, and connecting with the membrane component in the same way;
step 4, regulating a circulating pump, setting the flow, the flow speed and the transmembrane pressure of the receiving liquid and the feeding liquid, and starting the circulating pump;
step 5, monitoring the conductivity of the receiving liquid in real time by using a conductivity meter, sampling and detecting the concentration of ethanol in the receiving liquid at fixed time, and determining the ending operation time according to the use requirement;
and 6, optionally determining whether to replace the membrane material, and starting the next operation by replacing the receiving liquid.
2. The membrane extraction method for separating ethanol from ethanol high-salt wastewater according to claim 1, wherein in the step 1, the salt concentration in the ethanol high-salt wastewater ranges from 0g/L to 50g/L, the ethanol concentration ranges from 1 g/L to 10g/L, and the surface tension of the wastewater after insoluble matters are removed is more than 60mN/m (20 ℃).
3. The membrane extraction method for separating ethanol from ethanol high-salt wastewater according to claim 1, wherein in the step 1, the pH range of the wastewater is 5-8, the temperature is 25+ -5 ℃, and the stirring rotation speed is 100-500 r/min.
4. The membrane extraction method for separating ethanol from ethanol high-salt wastewater according to claim 1, wherein in step 2, the water contact angle of the hydrophobic and organophilic porous or thin layer composite membrane is greater than 110 ° and the ethanol contact angle is less than 40 °.
5. The membrane extraction method for separating ethanol from ethanol high-salt wastewater according to claim 1, wherein in the step 2, the pore size of the hydrophobic and organophilic porous membrane is 0.1-1 μm, and the pore size of the thin-layer composite membrane is 0-0.1 μm.
6. The membrane extraction method for separating ethanol from ethanol high-salt wastewater as claimed in claim 1, wherein in the step 2, the water flow mode in the membrane module is cross flow, and the effective membrane area of the single membrane module is 20-100 cm 2 The component is made of stainless steel or polytetrafluoroethylene.
7. The membrane extraction method for separating ethanol from ethanol high-salt wastewater according to claim 1, wherein in the step 3, the pH of the receiving liquid is 2-12, and the temperature is 15-35 ℃.
8. The membrane extraction process for separating ethanol from ethanol high-salinity wastewater according to claim 1, wherein in step 4, the operating parameters are as follows: the flow rate of the feed liquid and the receiving liquid is 0.1-10 cm/s, the flow rate is 0.1-50L/h, and the transmembrane hydraulic pressure is 0-20 kPa.
9. Use of a membrane extraction process according to any one of claims 1 to 8 for separating ethanol from ethanol high-salinity wastewater in wastewater treatment and wastewater reclamation.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58180442A (en) * | 1982-04-19 | 1983-10-21 | Asahi Chem Ind Co Ltd | Separation and concentration method of ethanol from aqueous solution thereof |
| CN101559993A (en) * | 2009-05-19 | 2009-10-21 | 新奥科技发展有限公司 | Method for removing trace alcohol in organic wastewater |
| CN102228801A (en) * | 2011-05-16 | 2011-11-02 | 何涛 | Hydrophobically modified distillation membrane material of high throughout and high salt rejection rate and application thereof |
| CN104609621A (en) * | 2013-11-01 | 2015-05-13 | 中国石油化工股份有限公司 | High-salt waste water treatment method |
-
2022
- 2022-08-31 CN CN202211052854.5A patent/CN115340151B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58180442A (en) * | 1982-04-19 | 1983-10-21 | Asahi Chem Ind Co Ltd | Separation and concentration method of ethanol from aqueous solution thereof |
| CN101559993A (en) * | 2009-05-19 | 2009-10-21 | 新奥科技发展有限公司 | Method for removing trace alcohol in organic wastewater |
| CN102228801A (en) * | 2011-05-16 | 2011-11-02 | 何涛 | Hydrophobically modified distillation membrane material of high throughout and high salt rejection rate and application thereof |
| CN104609621A (en) * | 2013-11-01 | 2015-05-13 | 中国石油化工股份有限公司 | High-salt waste water treatment method |
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