CN111573916A - Method and system for recycling dimethyl formamide wastewater - Google Patents
Method and system for recycling dimethyl formamide wastewater Download PDFInfo
- Publication number
- CN111573916A CN111573916A CN202010434976.5A CN202010434976A CN111573916A CN 111573916 A CN111573916 A CN 111573916A CN 202010434976 A CN202010434976 A CN 202010434976A CN 111573916 A CN111573916 A CN 111573916A
- Authority
- CN
- China
- Prior art keywords
- wastewater
- treatment
- alkaline hydrolysis
- reverse osmosis
- dimethylamine
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F9/00—Multistage treatment of water, waste water or sewage
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
- B01D53/1487—Removing organic compounds
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
- C07C209/82—Purification; Separation; Stabilisation; Use of additives
- C07C209/86—Separation
-
- 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
- C02F1/02—Treatment of water, waste water, or sewage by heating
-
- 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
- C02F1/20—Treatment of water, waste water, or sewage by degassing, i.e. liberation of dissolved gases
-
- 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
- C02F1/441—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by reverse osmosis
-
- 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
- C02F1/444—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by ultrafiltration or microfiltration
-
- 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
- C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
- C02F1/469—Treatment of water, waste water, or sewage by electrochemical methods by electrochemical separation, e.g. by electro-osmosis, electrodialysis, electrophoresis
- C02F1/4693—Treatment of water, waste water, or sewage by electrochemical methods by electrochemical separation, e.g. by electro-osmosis, electrodialysis, electrophoresis electrodialysis
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/30—Organic compounds
- C02F2101/38—Organic compounds containing nitrogen
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/22—Nature of the water, waste water, sewage or sludge to be treated from the processing of animals, e.g. poultry, fish, or parts thereof
- C02F2103/24—Nature of the water, waste water, sewage or sludge to be treated from the processing of animals, e.g. poultry, fish, or parts thereof from tanneries
Abstract
The invention discloses a method and a system for recycling dimethylformamide wastewater, belonging to the technical field of wastewater treatment. The method comprises the following steps: 1) alkaline hydrolysis stripping reaction: introducing the dimethylformamide wastewater into an alkaline hydrolysis stripping reactor, adding sodium hydroxide for alkaline hydrolysis reaction, and simultaneously heating and aerating to strip to generate dimethylamine gas and wastewater containing sodium formate; 2) reverse osmosis membrane treatment: introducing the wastewater into a reverse osmosis membrane system for treatment to obtain concentrated water containing reverse osmosis; 3) bipolar membrane electrodialysis treatment: and (3) enabling the reverse osmosis concentrated water obtained in the step 2) to enter a bipolar membrane electrodialysis system for treatment to obtain a sodium hydroxide solution and a formic acid solution, and enabling the sodium hydroxide solution to be led into the step 1) for recycling. The method of the invention can realize the resource utilization of the sodium hydroxide; meanwhile, sodium formate in the wastewater can be removed, the problem of overhigh salt content is avoided, and the zero emission requirement of the wastewater can be met.
Description
Technical Field
The invention belongs to the field of wastewater treatment, and particularly relates to a method and a system for recycling dimethylformamide wastewater.
Background
Dimethylformamide (DMF) is an excellent organic solvent and a fine chemical raw material, has wide industrial application, and is widely applied to synthetic leather production, polyacrylonitrile filament drawing, butadiene extraction and other processes. DMF has stable property, high toxicity and poor biodegradability. The amount of DMF wastewater discharged by synthetic leather industry in China is about 1 hundred million tons each year, which causes serious pollution to the environment.
Dimethyl amine and sodium formate can be generated by DMF alkaline hydrolysis (NaOH) reaction, the main component of the wastewater is sodium formate after aeration stripping, the biochemical property is high, and the wastewater can directly enter a biochemical system for treatment. The dimethylamine that blows off generally absorbs with the acid wash tower, and the solution after the absorption evaporates the stoving recovery of crystallization, and the waste water after blowing off gets into biochemical system and handles the back and discharges.
However, the conventional indexes such as COD of the wastewater after biochemical treatment can reach the standard, but the pH value of the DMF wastewater needs to be adjusted by adding alkali in the alkaline hydrolysis process, so that the salt content of the biochemical wastewater is easily higher. Therefore, the desalting treatment needs to be considered, and if the evaporative crystallization process is adopted, the investment is large, the operation cost is high, meanwhile, the generated miscellaneous salt has no additional value, and the miscellaneous salt needs to be treated as hazardous waste. Therefore, a more scientific process method needs to be selected for the treatment of the wastewater after the alkaline hydrolysis and air stripping of DMF.
Through retrieval, related applications are disclosed in the prior art, for example, the prior art with application number CN2015107252510 discloses a method for treating organic nitrogen DMF chemical wastewater, which comprises the following steps: A. high-concentration DMF wastewater flows into a materialized collection tank; B. conveying the wastewater in the materialized collection tank to an alkalization regulation tank; C. delivering the effluent of the alkalization regulating tank to a thermal stripping tower; D. tail gas of the heat stripping tower is absorbed in series by a two-stage absorption tower, and the tail gas treated by the second-stage absorption tower is discharged at high altitude; E. after the waste water in the thermal stripping tower is thermally stripped, the waste water is conveyed to a biochemical regulating tank; F. the effluent of the biochemical regulating tank enters a biochemical aerobic tank I; G. the effluent of the biochemical aerobic tank I is conveyed into a biochemical anoxic tank; H. the effluent of the biochemical anoxic tank is conveyed to a biochemical aerobic tank II, and the nitrifying liquid in the biochemical aerobic tank II flows back to the biochemical anoxic tank; I. and (3) returning the sludge in the secondary sedimentation tank to the biochemical aerobic tank I, and directly discharging the effluent with ammonia nitrogen less than 15 mg/L.
For example, the prior art with the application number of CN201580002436.7 discloses a treatment process of synthetic leather production wastewater, which sequentially comprises the following steps: grating treatment, pH and temperature adjustment, air stripping treatment, air floatation treatment, anaerobic degradation by adding domestic sewage, aerobic degradation, precipitation and MBR treatment. The adoption of the process ensures the stability of the water quality degraded by an aerobic biological method, reduces the later process requirement and ensures the water quality of the effluent; the removal rate of dimethylamine after stripping treatment reaches 81%, the problem of odor of distilled wastewater is well solved, dimethylamine in the wastewater can be recycled, waste is changed into valuable, and the wastewater reaches the standard and is discharged.
The methods of the above applications do not relate to the recovery of dimethylamine salt after stripping and absorption; and the wastewater after alkaline hydrolysis is discharged by adopting biochemical treatment without considering the salt content index.
Then, as the prior art with the application number of CN2017112622767, a method and a system for comprehensively treating DMF wastewater in membrane production are disclosed, wherein the DMF wastewater is subjected to alkaline hydrolysis after being homogenized and regulated in average amount, stripping is performed after the alkaline hydrolysis, dimethylamine waste gas after stripping enters an absorption packed tower and is absorbed by acid to form dimethylamine salt solution, and the dimethylamine salt solution is distilled, dried and then recovered; the wastewater after stripping adopts a multi-stage anaerobic and aerobic biochemical treatment combined process, the biochemical effluent is subjected to coagulating sedimentation, and the supernatant after sedimentation is subjected to membrane treatment and then is discharged after reaching the standard or is used for reclaimed water recycling. Although the recovery of dimethylamine salt after stripping is considered in the application, the wastewater after alkaline hydrolysis is discharged by biochemical treatment, and the salt content index is not considered.
Based on the defects of the prior art, the invention of a novel method for recycling the dimethylformamide wastewater is needed.
Disclosure of Invention
1. Problems to be solved
Aiming at the problems that in the prior art, alkali reaction is required to be added in the alkaline hydrolysis treatment process of the dimethyl formamide wastewater, the wastewater obtained after the reaction is directly subjected to biochemical treatment, so that the salt (sodium salt) content in the finally treated wastewater is high and the utilization of the wastewater is limited, the method disclosed by the invention has the advantages that the wastewater solution containing sodium formate after the alkaline hydrolysis stripping treatment firstly enters a reverse osmosis membrane for treatment, so that the concentrated sodium formate solution and the recyclable membrane produced water are obtained; then, sodium formate solution enters a bipolar membrane electrodialysis system for treatment to obtain sodium hydroxide solution and formic acid solution, so that the sodium hydroxide solution can be reused for alkaline hydrolysis stripping reaction, and resource utilization is realized; and sodium formate in the treated wastewater is removed, so that the problem of overhigh salt content is avoided, and the zero emission requirement of the wastewater can be realized.
Further, aiming at the problem that dimethylamine salt gas after alkaline hydrolysis stripping reaction can not be effectively recovered in the prior art, the dimethylamine gas discharged in the alkaline hydrolysis stripping reaction is led into a dimethylamine absorption device, hydrochloric acid solution is adopted to absorb the dimethylamine gas to obtain dimethylamine salt solution, and evaporation and drying are carried out to obtain dried dimethylamine salt crystals, so that the resource recovery of dimethylamine is realized.
2. Technical scheme
In order to solve the problems, the technical scheme adopted by the invention is as follows:
the invention provides a method for recycling Dimethylformamide (DMF) wastewater, which comprises the following steps:
1) alkaline hydrolysis stripping reaction: introducing the collected dimethylformamide wastewater into an alkaline hydrolysis stripping reactor, adding sodium hydroxide for alkaline hydrolysis reaction, and simultaneously heating and aerating to strip to generate dimethylamine gas and wastewater containing sodium formate;
2) reverse osmosis membrane treatment: introducing the wastewater treated in the step 1) into a reverse osmosis membrane system for treatment to obtain reverse osmosis concentrated water and reverse osmosis produced water, wherein the reverse osmosis concentrated water is a sodium formate solution;
3) bipolar membrane electrodialysis treatment: and (2) allowing the sodium formate solution to enter a bipolar membrane electrodialysis system for treatment to obtain a sodium hydroxide solution and a formic acid solution, and introducing the sodium hydroxide solution obtained in the step 1) for recycling.
The bipolar membrane electrodialysis treatment system adopted in the step 3) is a bipolar membrane electrodialysis treatment system commonly used in the prior art, and aims to: the method can convert the salt in the aqueous solution into the corresponding formic acid solution and sodium hydroxide solution without introducing new components, thereby recycling the sodium hydroxide solution as a medicament in the alkaline hydrolysis stripping reaction, solving the problem of sodium formate treatment in the wastewater and realizing the resource utilization of the sodium hydroxide. And the sodium hydroxide medicament is added once before the system operates, and the sodium hydroxide required after the system operates normally is generated by bipolar membrane electrodialysis treatment, so that the operation cost is greatly reduced.
Preferably, the mass ratio of the sodium hydroxide initially added in the step 1) to the DMF in the wastewater is (1-1.5): 1.
preferably, the wastewater treated in the step 1) needs to be treated by an ultrafiltration membrane system before entering a reverse osmosis membrane system for treatment, so as to obtain ultrafiltration product water and ultrafiltration concentrated water, and then the ultrafiltration product water is introduced into the reverse osmosis membrane system for treatment.
Preferably, the method further comprises the step of recovering dimethylamine: introducing dimethylamine gas discharged from the alkaline hydrolysis stripping reactor into a dimethylamine absorption system, absorbing the dimethylamine gas by using a hydrochloric acid solution to obtain a dimethylamine salt solution, and evaporating and drying to obtain a dried dimethylamine salt crystal.
Preferably, the dimethylamine absorption system comprises a first-stage concentration tower, a multistage acid washing tower and a tail end water washing tower which are connected in series in sequence, wherein the concentration tower is used for concentrating dimethylamine hydrochloride, and the acid washing tower is used for absorbing dimethylamine gas.
Preferably, the acid washing tower comprises three stages, the absorbent adopts hydrochloric acid solution with the mass concentration of 5-10%, and the absorption liquid obtained after the treatment of the first-stage acid washing tower is input into the second-stage acid washing tower; the second-stage acid washing tower is a coarse absorption tower, and absorption liquid obtained after treatment of the second-stage acid washing tower is input into the third-stage acid washing tower; the tertiary tower is fine absorption tower, and absorption efficiency is high, ensures that dimethylamine discharges up to standard, for avoiding exhaust emission acid mist to form, the end sets up one-level water washing tower and guarantees.
Preferably, the method further comprises a dimethylamine salt drying step, wherein the absorption liquid treated by the dimethylamine absorption system is introduced into a dimethylamine salt drying device for treatment, and a multi-effect evaporator and a drying system are utilized for treatment to obtain dried dimethylamine salt crystals.
Preferably, the heating temperature in the step 1) is maintained at 30-80 ℃, and the aeration conditions are as follows: an air aeration source is used, and the gas-liquid ratio is maintained at (500-1500): 1.
preferably, the height-diameter ratio of the alkaline hydrolysis stripping reactor is (2-10): 1, the retention time of the wastewater in the reactor is 2-6 h.
Preferably, the flow velocity of water in the acid washing tower is 1-3 m/s, the coverage rate of a nozzle in the tower is 200%, and the height of the tower is 6-9 m.
Preferably, the invention provides a system for recycling dimethylformamide wastewater, which comprises an alkaline hydrolysis stripping reactor, a reverse osmosis membrane system and a bipolar membrane electrodialysis system which are sequentially communicated, wherein a water inlet of the reverse osmosis membrane system is communicated with a water outlet of the alkaline hydrolysis stripping reactor, a connecting pipeline is arranged between a concentrated osmosis water side of the reverse osmosis membrane system and the bipolar membrane electrodialysis system, and a sodium hydroxide solution return pipeline is arranged between the bipolar membrane electrodialysis system and the alkaline hydrolysis stripping reactor.
Preferably, an ultrafiltration system is further arranged between the alkaline hydrolysis stripping reactor and the reverse osmosis system, an ultrafiltration element in the ultrafiltration system adopts an inorganic membrane element, and the alkaline hydrolysis stripping reactor, the ultrafiltration system, the reverse osmosis membrane system and the bipolar membrane electrodialysis system are sequentially communicated.
Preferably, the alkaline hydrolysis stripping reactor is an integrated device and comprises a stripping unit and a heating unit; the air stripping unit adopts aeration air stripping, and the heating unit adopts heating through a steam coil. The heating device adopts steam as a heat source, adopts a coil type, and is made of alloy materials; the aeration equipment adopts a Roots blower.
3. Advantageous effects
1) The method for recycling the dimethylformamide wastewater disclosed by the invention has the advantages that the wastewater solution after alkaline hydrolysis stripping treatment firstly enters a reverse osmosis membrane for treatment to obtain a concentrated sodium formate solution and membrane produced water (the membrane produced water can be recycled); then the sodium formate solution enters a bipolar membrane treatment system for treatment to obtain a sodium hydroxide solution and a formic acid solution, and the sodium hydroxide solution can be reused for alkaline hydrolysis stripping reaction to realize resource utilization; and sodium formate in the treated wastewater is removed, so that the problem of overhigh salt content is avoided, and the zero emission requirement of the wastewater can be realized.
2) The method for recycling the dimethylformamide wastewater can realize the recycling of the wastewater, the sodium hydroxide generated in the process can be recycled to the alkaline hydrolysis reaction system, the operation cost of the medicament is saved, only a small amount of sodium hydroxide is added when the system is operated and started, and the supply of the medicament in the subsequent alkaline hydrolysis reaction only needs to depend on the sodium hydroxide solution generated by the bipolar membrane electrodialysis system, so the operation cost of the process is greatly reduced.
3) According to the method for recycling the dimethylformamide wastewater, dimethylamine gas discharged after alkaline hydrolysis stripping reaction enters a dimethylamine absorption device for further treatment, a hydrochloric acid solution is adopted to absorb the dimethylamine gas in the treatment process to obtain a dimethylamine salt solution, and evaporation and drying are carried out to obtain dried dimethylamine salt crystals with the purity of more than 99%, wherein the product has high purity and can be sold as a product; in addition, formic acid solution with the mass concentration of 5.4% can be obtained after bipolar membrane electrodialysis treatment, and the formic acid solution is sold as a product.
Drawings
FIG. 1 is a schematic flow chart of the invention for the resource treatment of the dimethylformamide wastewater.
Detailed Description
It should be noted that the terms "upper", "lower", "left", "right" and "middle" used in the present specification are for the sake of clarity, and are not intended to limit the scope of the present invention, and changes or adjustments of the relative relationship thereof may be made without substantial technical changes.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs; as used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
As used herein, the term "about" is used to provide the flexibility associated with a given term, metric, or value. The degree of flexibility for a particular variable can be readily determined by one skilled in the art.
As used herein, at least one of the terms "is intended to be synonymous with one or more of. For example, "at least one of A, B and C" explicitly includes a only, B only, C only, and combinations thereof, respectively.
Concentrations, amounts, and other numerical data may be presented herein in a range format. It is to be understood that such a range format is used merely for convenience and brevity and should be interpreted flexibly to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. For example, a numerical range of about 1 to about 4.5 should be interpreted to include not only the explicitly recited limit values of 1 to about 4.5, but also include individual numbers (such as 2, 3, 4) and sub-ranges (such as 1 to 3, 2 to 4, etc.). The same principle applies to ranges reciting only one numerical value, such as "less than about 4.5," which should be construed to include all of the aforementioned values and ranges. Moreover, such an interpretation should apply regardless of the breadth of the range or feature being described.
Any steps recited in any method or process claims may be executed in any order and are not limited to the order presented in the claims.
The present invention is further described with reference to the accompanying drawings and specific embodiments so that those skilled in the art may better understand the present invention and can practice it, but the embodiments are not to be construed as limiting the present invention.
The method for recycling dimethylformamide wastewater provided in this embodiment (fig. 1 is a schematic flow chart for recycling dimethylformamide wastewater of the present invention), which comprises the following steps:
1) discharging DMF wastewater with the mass concentration of 5% into a collecting tank, caching in the collecting tank, adjusting the homogeneous uniform amount, then feeding the wastewater into an alkaline hydrolysis stripping reactor, wherein the alkaline hydrolysis stripping reactor is an integrated device comprising a heating system and a stripping system, adding a sodium hydroxide solution with the mass concentration of 30% into the alkaline hydrolysis stripping reactor for mixing reaction, and the mass ratio of the initially added sodium hydroxide to the DMF is (1-1.5): 1; heating the wastewater solution by using a heating system while adding a drug to react, keeping the heating temperature at 30-80 ℃, wherein a heat source adopts steam, a coil type is adopted, and the material is an alloy material; meanwhile, aeration is carried out by utilizing a stripping system in the device. The aeration conditions are as follows: with the air aeration source, the equipment adopts the roots blower, and the gas-liquid ratio is maintained at (500 ~ 1500): 1. the height-diameter ratio of the alkaline hydrolysis stripping reactor is (2-10): 1, the retention time of the wastewater in the reactor is 2-6 h.
The removal efficiency of DMF treated by the alkaline hydrolysis stripping reactor in the step 1) is more than 99.9 percent, and the wastewater after the reaction contains a large amount of sodium formate, the concentration of which in water is 43170 mg/L.
2) Step 1) blows off and produces dimethylamine gas and adopts dimethylamine absorption system to absorb, dimethylamine absorption system includes head end concentration tower, the acid washing tower and the terminal water washing tower of tertiary series connection, concentration tower is used for the concentration of dimethylamine hydrochloride, the acid washing tower of tertiary series connection is used for the gaseous absorption of dimethylamine, contains the hydrochloric acid solution that mass concentration is 5 ~ 10% in the acid washing tower as the absorbent, and the terminal water washing tower that sets up ensures.
The acid washing tower comprises three stages, and absorption liquid obtained after the treatment of the first-stage acid washing tower is input into the second-stage acid washing tower; the second-stage acid washing tower is a coarse absorption tower, and absorption liquid obtained after treatment of the second-stage acid washing tower is input into the third-stage acid washing tower; the tertiary tower is fine absorption tower, and absorption efficiency is high, ensures that dimethylamine discharges up to standard, for avoiding exhaust emission acid mist to form, the end sets up one-level water washing tower and guarantees.
The flow rate of water in the acid washing tower is 1-3 m/s, the coverage rate of a nozzle in the tower is 200%, and the height of the tower is 6-9 m.
After being treated by a dimethylamine absorption system, dimethylamine hydrochloride solution with the mass concentration of about 19.8 percent is formed, and then enters a dimethylamine salt drying device to be treated by a multi-effect evaporator and a drying system in the device, so that dried dimethylamine salt crystal with the purity of more than 99 percent is obtained. The product has high purity and can be sold as a product.
3) And (3) ultrafiltration treatment: introducing the wastewater containing sodium formate after the alkaline hydrolysis stripping reaction in the step 1) into an ultrafiltration system, wherein the ultrafiltration system is communicated with a water outlet of an alkaline hydrolysis stripping reactor, and an ultrafiltration element adopts an inorganic membrane element; aims to remove suspended matters in the wastewater, realize solid-liquid separation, ensure that the wastewater SDI is less than 5 and provide favorable conditions for subsequent reverse osmosis concentration;
4) reverse osmosis membrane treatment: introducing the wastewater treated in the step 1) into a reverse osmosis membrane system for treatment to obtain reverse osmosis concentrated water (namely sodium formate solution) and reverse osmosis produced water, wherein the reverse osmosis produced water can be directly recycled; the wastewater can be concentrated to more than 80000mg/L of sodium formate (salt content) by the treatment of the step to obtain sodium formate strong brine, so that the resource utilization rate of the system is improved; meanwhile, the salt content of the produced water of the reverse osmosis membrane component is lower than 100mg/L, so that the produced water can be recycled, zero discharge of waste water is realized, and the environment is protected.
5) Bipolar membrane electrodialysis treatment: and (3) allowing the sodium formate concentrated brine obtained in the step 2) to enter a bipolar membrane electrodialysis system for treatment to obtain a sodium hydroxide solution and a formic acid solution, and introducing the sodium hydroxide solution into the alkaline hydrolysis reactor in the step 1) for recycling. After the treatment of the step, a formic acid solution with the mass concentration of 5.4% is obtained, and the formic acid solution is sold as a product, so that the resource utilization of the DMF wastewater is really realized.
In the system, a water inlet of the ultrafiltration system is communicated with a water outlet of the alkaline hydrolysis stripping reactor, a water inlet of a reverse osmosis membrane system of the ultrafiltration system is communicated, a connecting pipeline is arranged between a permeation concentrated water side of the reverse osmosis membrane system and the bipolar membrane electrodialysis system, a return pipeline is arranged between the bipolar membrane electrodialysis system and the alkaline hydrolysis stripping reactor, and sodium hydroxide generated by the bipolar membrane electrodialysis system in the step 5) is introduced into the alkaline hydrolysis stripping reactor through the return pipeline for recycling.
The above description is only for the preferred embodiments of the present invention, but the embodiments of the present invention are not limited by the above embodiments, and any other changes, modifications, substitutions, combinations and equivalents which do not depart from the spirit and principle of the present invention should be regarded as being equivalent and included within the scope of the present invention.
Claims (10)
1. A method for the resource treatment of dimethylformamide wastewater is characterized in that: the method comprises the following steps:
1) alkaline hydrolysis stripping reaction: introducing the collected dimethylformamide wastewater into an alkaline hydrolysis stripping reactor, adding sodium hydroxide for alkaline hydrolysis reaction, and simultaneously heating and aerating to strip to generate dimethylamine gas and wastewater containing sodium formate;
2) reverse osmosis membrane treatment: introducing the wastewater treated in the step 1) into a reverse osmosis membrane system for treatment to obtain reverse osmosis concentrated water and reverse osmosis produced water, wherein the reverse osmosis concentrated water is a sodium formate solution;
3) bipolar membrane electrodialysis treatment: and (2) allowing the sodium formate solution to enter a bipolar membrane electrodialysis system for treatment to obtain a sodium hydroxide solution and a formic acid solution, and introducing the sodium hydroxide solution obtained in the step 1) for recycling.
2. The method for recycling dimethylformamide wastewater as claimed in claim 1, wherein: the wastewater treated in the step 1) needs to be treated by an ultrafiltration membrane system before entering a reverse osmosis membrane system to obtain ultrafiltration product water and ultrafiltration concentrated water, and then the ultrafiltration product water is led into the reverse osmosis membrane system to be treated.
3. The method for recycling dimethylformamide wastewater as claimed in claim 1 or 2, wherein: the method also comprises the step of recovering dimethylamine: introducing dimethylamine gas generated in the alkaline hydrolysis stripping reactor into a dimethylamine absorption system, absorbing the dimethylamine gas by using a hydrochloric acid solution to obtain a dimethylamine salt solution, and evaporating and drying to obtain a dried dimethylamine salt crystal.
4. The method for recycling dimethylformamide wastewater as claimed in claim 3, wherein: the dimethylamine absorption system comprises a concentration tower, a multistage acid washing tower and a tail end water washing tower which are connected in series in sequence, wherein the concentration tower is used for concentrating dimethylamine hydrochloride, the acid washing tower is used for absorbing dimethylamine gas, and/or the mass concentration of a hydrochloric acid solution is 5-10%.
5. The method for recycling dimethylformamide wastewater as claimed in claim 4, wherein: in the step 1), the heating temperature is maintained at 30-80 ℃, and the aeration conditions are as follows: an air aeration source is used, and the gas-liquid ratio is maintained at (500-1500): 1.
6. the method for recycling dimethylformamide wastewater as claimed in claim 1 or 2, wherein: the height-diameter ratio of the alkaline hydrolysis stripping reactor is (2-10): 1, the retention time of the wastewater in the reactor is 2-6 h.
7. The method for recycling dimethylformamide wastewater as claimed in claim 4, wherein: the flow rate of water in the acid washing tower is 1-3 m/s, the coverage rate of a nozzle in the tower is 200%, and the height of the tower is 6-9 m.
8. The utility model provides a system for dimethylformamide waste water resourceful treatment which characterized in that: the system is used for realizing the resource treatment method of the dimethylformamide wastewater as claimed in any one of claims 1 to 7, and comprises an alkaline hydrolysis stripping reactor, a reverse osmosis membrane system and a bipolar membrane electrodialysis system which are communicated in sequence, wherein a return pipeline for recycling a sodium hydroxide solution is arranged between the bipolar membrane electrodialysis system and the alkaline hydrolysis stripping reactor.
9. The system for resource treatment of dimethylformamide wastewater as claimed in claim 8, wherein: an ultrafiltration system is also arranged between the alkaline hydrolysis stripping reactor and the reverse osmosis system.
10. The system for resource treatment of dimethylformamide wastewater as claimed in claim 9, wherein: the alkaline hydrolysis stripping reactor comprises a stripping unit and a heating unit; the air stripping unit adopts aeration air stripping, and the heating unit adopts heating through a steam coil.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010434976.5A CN111573916A (en) | 2020-05-21 | 2020-05-21 | Method and system for recycling dimethyl formamide wastewater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010434976.5A CN111573916A (en) | 2020-05-21 | 2020-05-21 | Method and system for recycling dimethyl formamide wastewater |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111573916A true CN111573916A (en) | 2020-08-25 |
Family
ID=72115735
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010434976.5A Pending CN111573916A (en) | 2020-05-21 | 2020-05-21 | Method and system for recycling dimethyl formamide wastewater |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111573916A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112811670A (en) * | 2021-01-29 | 2021-05-18 | 浙江金潮实业有限公司 | Oily synthetic leather wastewater treatment and recovery system and method |
| CN114805924A (en) * | 2022-05-11 | 2022-07-29 | 南京大学环境规划设计研究院集团股份公司 | Method for recovering cross-linking agent from DMF (dimethyl formamide) wastewater by using waste alkali liquor |
| CN115594357A (en) * | 2022-11-08 | 2023-01-13 | 煤炭科学技术研究院有限公司（Cn） | Acylation wastewater grading treatment method |
| CN115838321A (en) * | 2022-10-10 | 2023-03-24 | 南通百川新材料有限公司 | Electrodialysis membrane separation method for desalting green color in trimethylolpropane |
| CN116375300A (en) * | 2023-06-05 | 2023-07-04 | 威海蓝创环保设备有限公司 | DMF (dimethyl formamide) -containing wastewater treatment process |
| CN116395915A (en) * | 2023-06-07 | 2023-07-07 | 威海蓝创环保设备有限公司 | Sponge production wastewater treatment system |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010061811A (en) * | 2008-09-01 | 2010-03-18 | Sumitomo Wiring Syst Ltd | Production line of insulation wire, and method of manufacturing insulation wire |
| JPWO2010061811A1 (en) * | 2008-11-27 | 2012-04-26 | 栗田工業株式会社 | Apparatus and method for separating and recovering water-soluble organic solvent having amino group |
| KR20130101279A (en) * | 2012-03-05 | 2013-09-13 | 웅진케미칼 주식회사 | Method for separating and recovering dimethylformaide in industrial waste water |
| CN105198174A (en) * | 2015-10-29 | 2015-12-30 | 南京大学盐城环保技术与工程研究院 | Method for treating chemical industry wastewater containing organic nitrogen DMF (N,N-dimethylformamide) |
| CN107673571A (en) * | 2017-12-04 | 2018-02-09 | 湖南大辰环保科技有限公司 | DMF comprehensive treatment method for wastewater and system in a kind of film production |
| CN207108514U (en) * | 2017-08-23 | 2018-03-16 | 盛隆资源再生（无锡）有限公司 | The device for mixing Nacl effluent resource and utilizing is realized using membrane separation technique |
| CN108059281A (en) * | 2017-12-25 | 2018-05-22 | 南京工业大学 | Coal chemical industrial waste water embrane method zero discharge treatment technology |
| CN208166735U (en) * | 2018-02-11 | 2018-11-30 | 英德市匠心新材料股份有限公司 | DMF waste water reclaiming device in a kind of production of synthetic leather |
| CN111039477A (en) * | 2019-12-30 | 2020-04-21 | 杭州蓝然环境技术股份有限公司 | Method for recycling and comprehensively utilizing reverse osmosis concentrated water of coking wastewater |
-
2020
- 2020-05-21 CN CN202010434976.5A patent/CN111573916A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010061811A (en) * | 2008-09-01 | 2010-03-18 | Sumitomo Wiring Syst Ltd | Production line of insulation wire, and method of manufacturing insulation wire |
| JPWO2010061811A1 (en) * | 2008-11-27 | 2012-04-26 | 栗田工業株式会社 | Apparatus and method for separating and recovering water-soluble organic solvent having amino group |
| KR20130101279A (en) * | 2012-03-05 | 2013-09-13 | 웅진케미칼 주식회사 | Method for separating and recovering dimethylformaide in industrial waste water |
| CN105198174A (en) * | 2015-10-29 | 2015-12-30 | 南京大学盐城环保技术与工程研究院 | Method for treating chemical industry wastewater containing organic nitrogen DMF (N,N-dimethylformamide) |
| CN207108514U (en) * | 2017-08-23 | 2018-03-16 | 盛隆资源再生（无锡）有限公司 | The device for mixing Nacl effluent resource and utilizing is realized using membrane separation technique |
| CN107673571A (en) * | 2017-12-04 | 2018-02-09 | 湖南大辰环保科技有限公司 | DMF comprehensive treatment method for wastewater and system in a kind of film production |
| CN108059281A (en) * | 2017-12-25 | 2018-05-22 | 南京工业大学 | Coal chemical industrial waste water embrane method zero discharge treatment technology |
| CN208166735U (en) * | 2018-02-11 | 2018-11-30 | 英德市匠心新材料股份有限公司 | DMF waste water reclaiming device in a kind of production of synthetic leather |
| CN111039477A (en) * | 2019-12-30 | 2020-04-21 | 杭州蓝然环境技术股份有限公司 | Method for recycling and comprehensively utilizing reverse osmosis concentrated water of coking wastewater |
Non-Patent Citations (2)
| Title |
|---|
| 乌锡康: "《有机化工废水治理技术》", 31 July 1999, 化学工业出版社, pages: 213 - 215 * |
| 马兴元: "《合成革化学与工艺学》", 30 November 2015, 中国轻工业出版社, pages: 276 - 278 * |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112811670A (en) * | 2021-01-29 | 2021-05-18 | 浙江金潮实业有限公司 | Oily synthetic leather wastewater treatment and recovery system and method |
| CN114805924A (en) * | 2022-05-11 | 2022-07-29 | 南京大学环境规划设计研究院集团股份公司 | Method for recovering cross-linking agent from DMF (dimethyl formamide) wastewater by using waste alkali liquor |
| CN115838321A (en) * | 2022-10-10 | 2023-03-24 | 南通百川新材料有限公司 | Electrodialysis membrane separation method for desalting green color in trimethylolpropane |
| CN115594357A (en) * | 2022-11-08 | 2023-01-13 | 煤炭科学技术研究院有限公司（Cn） | Acylation wastewater grading treatment method |
| CN115594357B (en) * | 2022-11-08 | 2024-04-19 | 煤炭科学技术研究院有限公司 | Fractional treatment method for acylated wastewater |
| CN116375300A (en) * | 2023-06-05 | 2023-07-04 | 威海蓝创环保设备有限公司 | DMF (dimethyl formamide) -containing wastewater treatment process |
| CN116375300B (en) * | 2023-06-05 | 2023-09-19 | 威海蓝创环保设备有限公司 | DMF (dimethyl formamide) -containing wastewater treatment process |
| CN116395915A (en) * | 2023-06-07 | 2023-07-07 | 威海蓝创环保设备有限公司 | Sponge production wastewater treatment system |
| CN116395915B (en) * | 2023-06-07 | 2023-09-19 | 威海蓝创环保设备有限公司 | Sponge production wastewater treatment system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111573916A (en) | Method and system for recycling dimethyl formamide wastewater | |
| US10793458B2 (en) | Process to recover ammonium bicarbonate from wastewater | |
| CN101264948B (en) | Ammonia nitrogen waste water discharge-reducing and ammonia nitrogen resource utilizing device and method | |
| US11254581B2 (en) | Process to recover ammonium bicarbonate from wastewater | |
| US20120315209A1 (en) | Methods and systems for treating water streams | |
| CN101497617B (en) | Method for producing hexamethylene tetramin by formaldehyde-containing wastewater | |
| CN107758960A (en) | A kind of processing method of ammonia waste water | |
| CN103771642A (en) | Recycling method for saponified ammonium-sulfate wastewater in rare soil | |
| CN104003564A (en) | Wet-process rare earth smelting high ammonia-nitrogen wastewater resource utilization method and device | |
| CN111704310A (en) | Stainless steel comprehensive wastewater zero discharge system and process method | |
| CN203602435U (en) | Resourceful treatment process system for extracting high-concentration ammonia water from ammonia-nitrogen wastewater | |
| CN105565615B (en) | A kind of technique of pentaerythrite wastewater to reach standard processing | |
| CN107200435A (en) | A kind of nickel-containing waste water processing method, processing system and application | |
| WO2023165020A1 (en) | Method for deamination treatment of ammonia-nitrogen wastewater | |
| CN113562913B (en) | Treatment method of hydrazine hydrate production wastewater | |
| CN108164068A (en) | A kind of pretreating process of mt. production waste water | |
| CN108128829A (en) | Taurine waste water zero discharge treatment process and taurine wastewater zero discharge processing unit | |
| CN210885671U (en) | Recovery unit of metribuzin production waste acid water | |
| CN100364900C (en) | Method for concentrating ammonium chloride using reverse osmosis membrane | |
| CN103212424A (en) | Method for recycling glycol and acetaldehyde in polyester waste water | |
| WO2020131116A1 (en) | Process to recover ammonium bicarbonate from wastewater | |
| CN113698017B (en) | Resource utilization and treatment method of alkynol wastewater | |
| CN113698043B (en) | Resource utilization and advanced treatment method for raw material medicine production process wastewater | |
| NL2003086C2 (en) | METHOD AND DEVICE FOR HANDLING AMMONIUM WASTE WATER. | |
| CN116947262A (en) | Landfill leachate recycling treatment system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200825 |
|
| RJ01 | Rejection of invention patent application after publication |