CN111018214A - Method for reducing COD content in waste water discharged from cyclohexanone device - Google Patents
Method for reducing COD content in waste water discharged from cyclohexanone device Download PDFInfo
- Publication number
- CN111018214A CN111018214A CN201811179210.6A CN201811179210A CN111018214A CN 111018214 A CN111018214 A CN 111018214A CN 201811179210 A CN201811179210 A CN 201811179210A CN 111018214 A CN111018214 A CN 111018214A
- Authority
- CN
- China
- Prior art keywords
- condensate
- cyclohexanone
- recovery tank
- reaction kettle
- cod content
- 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.)
- Granted
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
-
- 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
- C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
- C02F1/10—Treatment of water, waste water, or sewage by heating by distillation or evaporation by direct contact with a particulate solid or with a fluid, as a heat transfer medium
-
- 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
- C02F1/26—Treatment of water, waste water, or sewage by extraction
-
- 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
- C02F2103/34—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32
- C02F2103/36—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32 from the manufacture of organic compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/08—Chemical Oxygen Demand [COD]; Biological Oxygen Demand [BOD]
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Water, Waste Water Or Sewage (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a method for reducing the COD content in waste water discharged from a cyclohexanone device, which is characterized in that on the premise of ensuring the water seal function of a condensate recovery tank, a booster pump is arranged to continuously or discontinuously pump condensate in the condensate recovery tank into a decomposition reaction kettle. The invention designs a production process with a condensate recovery tank and a decomposition reaction kettle connected in series, wherein a booster pump is arranged to continuously or discontinuously pump the condensate in the condensate recovery tank into the decomposition reaction kettle, the condensate is used as make-up water of the decomposition reaction kettle, the process water can be replaced to supplement the decomposition reaction kettle, and meanwhile, the condensate is extracted and separated by a large amount of cyclohexane in the decomposition liquid, so that the content of organic matters in the condensate is reduced.
Description
Technical Field
The invention relates to a method for reducing COD content in waste water discharged from a cyclohexanone device, belonging to the technical field of cyclohexanone production.
Background
Cyclohexane oxidation is a common cyclohexanone production process. The method takes cyclohexane as a raw material, and the cyclohexane is oxidized by oxygen-enriched air under the condition of no catalysis to obtain an oxidation liquid, wherein the main component of the oxidation liquid is cyclohexyl hydroperoxide. The oxidation liquid is decomposed after being treated by alkali liquor, and cyclohexanone, cyclohexanol and other products, such as ester, acid, aldehyde and the like, can be obtained.
During the process of treating the oxidation liquid by the alkali liquor, the acid in the oxidation liquid is neutralized, and the ester is subjected to saponification reaction to generate organic acid sodium salt and cyclohexanol. Small amounts of ketones and aldehydes in the oxidation liquid condense to form dimers and trimers. After the reaction is finished, waste lye containing a small amount of cyclohexanone, cyclohexanol and a large amount of cyclohexane can be obtained. The waste alkali liquor enters a waste alkali separation process, and an organic phase containing a small amount of cyclohexanone, cyclohexanol and a large amount of cyclohexane can be separated from alkali and water. And (3) feeding the organic phase obtained in the waste alkali separation process into a cyclohexane distillation process to obtain a crude alcohol ketone material with the total content of cyclohexanol and cyclohexanone being more than 90%.
The crude alcohol ketone material is sent to a primary distillation tower to remove light components after saponification, salt extraction and drying, alcohol ketone material with the total content of cyclohexanol and cyclohexanone being more than 95 percent can be obtained, and cyclohexanone and cyclohexanol can be obtained after further rectification. And dehydrogenating cyclohexanol to obtain cyclohexanone.
Because the boiling points of cyclohexanone, cyclohexanol and some by-products are very close, the cyclohexanone/cyclohexanol column is operated under negative pressure, and each column is separately provided with a vacuum pumping system. The vacuum system generally adopts a mode of steam or a combination of a water ring and the steam to vacuumize. This evacuation produces a condensate (aqueous phase) containing cyclohexanone, cyclohexanol and other organic compounds. The solubility of cyclohexanone/cyclohexanol in water is relatively high, so that the COD content of the condensate is above 40000mg/L, and the washing effect of other washing processes can be influenced if the condensate is used in other washing processes. In addition, the condensate, if not treated, also increases the environmental pressure and the material consumption of the device.
In the existing production process, the condensate is recycled to a recovery tank, which generally performs both separation and water sealing. However, in actual practice, the recovery process has the following problems:
(1) because the content of organic matters in the condensate is too high, the condensate recovery tank is often replaced by a large amount of fresh process water, the amount of the internal circulation process water of the device is large, the amount of the external wastewater of the device is increased, and the COD content in the external wastewater reaches 10000-20000 mg/L. Meanwhile, the organic matters are layered in the condensate recovery tank, so that part of the cyclohexanone/cyclohexanol enters a downstream environment-friendly treatment device during replacement although part of the organic materials are recovered, the treatment load of an environment-friendly facility is increased, and the material consumption is increased.
(2) The organic matter dissolved in the condensate can affect the water washing effect of the organic material in the salt extraction tower, so that the sodium ion content in the organic material treated by the salt extraction tower is higher, and the consumption of process water is increased or fresh process water is used. The process water amount of the circulating water in the salt extraction tower is increased, and the external process water amount is increased, so that the external waste water amount of the device is increased.
In conclusion, in the prior art, the process of recovering cyclohexanone/cyclohexanol vacuumized condensate has the defects of incomplete condensate separation, large discharged wastewater amount, high COD content in discharged wastewater and the like.
Disclosure of Invention
Aiming at the defects of incomplete separation of condensate, large amount of discharged wastewater, high COD content in the discharged wastewater and the like in the vacuum-pumping condensate recovery process of cyclohexanone/cyclohexanol in the prior art, the invention aims to provide the method for effectively reducing the COD content in the discharged wastewater of the cyclohexanone device.
In order to achieve the technical purpose, the invention provides a method for reducing the COD content in the waste water discharged from a cyclohexanone device, and on the premise of ensuring the water sealing function of a condensate recovery tank, a booster pump is arranged to continuously or discontinuously pump the condensate of the condensate recovery tank into a decomposition reaction kettle.
The invention designs a production process with a condensate recovery tank and a decomposition reaction kettle connected in series, wherein a booster pump is arranged to continuously or discontinuously pump the condensate in the condensate recovery tank into the decomposition reaction kettle, the condensate is used as make-up water of the decomposition reaction kettle, the process water can be replaced to supplement the decomposition reaction kettle, and meanwhile, the condensate is extracted and separated by a large amount of cyclohexane in the decomposition liquid, so that the content of organic matters in the condensate is reduced.
Preferably, under the premise of ensuring the water sealing function of the condensate recovery tank, the upper organic phase is ejected out and sent to the inlet of the booster pump through the condensate of the condensate recovery tank or supplemented process water entering the condensate tank.
Preferably, a baffle is arranged in the condensate recovery tank. The baffle is mainly used for separating the organic phase from the aqueous phase, and can also increase the retention time of the organic phase and the aqueous phase so that the organic phase and the aqueous phase are separated more fully.
In the preferable scheme, the gas phase vent at the top of the condensate recovery tank is higher than the organic phase outlet by more than 100 mm.
Preferably, the outlet pipeline of the booster pump is directly connected with the decomposition reaction kettle body; or is connected with an oxidation liquid pipeline entering the decomposition reaction kettle.
According to the invention, the condensate (organic phase and inorganic phase) of the condensate recovery tank is continuously or discontinuously pumped into the decomposition reaction kettle, the condensate is used as make-up water of the decomposition reaction kettle, the use amount of process water is reduced, and meanwhile, the condensate is extracted through a large amount of cyclohexane in the decomposition liquid, so that the content of organic matters in the condensate is reduced. And after oil-water separation is carried out on the decomposition liquid, the organic phase is treated and recovered in a cyclohexane distillation process. The whole process is carried out in a relatively closed system, so that the discharge of gas phase is reduced, and air pollution and water phase secondary pollution are prevented. Meanwhile, the operation intensity of operators is not required to be excessively increased; and the water phase is treated by a waste alkali evaporation process, the evaporated water phase is used as process water of the device, redundant water is sent to a wastewater stripping tower for stripping, the COD content of wastewater in the kettle of the stripping tower is 2000-3000 mg/l, and the wastewater is sent to an environment-friendly device for treatment. The COD content in the wastewater in the bottom of the wastewater stripper tower is reduced to 1/10.
In summary, compared with the prior art, the technical scheme of the invention has the following beneficial effects:
1) the invention designs a production process with a condensate recovery tank and a decomposition reaction kettle connected in series, wherein a booster pump is arranged to continuously or discontinuously pump the condensate of the condensate recovery tank into the decomposition reaction kettle, the condensate is used as make-up water of the decomposition reaction kettle, so that the process water consumption is saved, and meanwhile, the condensate is extracted and separated by a large amount of cyclohexane in the decomposition liquid, so that the alcohol ketone in the condensate is effectively recovered, and the content of organic matters in the condensate is reduced.
2) The technical scheme provided by the invention is used for treating the cyclohexanone/cyclohexanol vacuumized condensate, can effectively remove organic matters in the condensate, and can control the COD content in the waste water discharged from the bottom of the stripping tower to be below 3000mg/L after decomposition reaction, waste alkali separation, waste alkali evaporation and waste water steam stripping treatment, thereby solving the problem of high COD content in the waste water discharged from the outside in the prior art, lightening the treatment load of an environment-friendly device and ensuring that the device is discharged in an environment-friendly and standard-reaching way.
3) The cyclohexanone/cyclohexanol vacuumizing condensate recovery production unit designed by the technical scheme of the invention has a simple structure, is easy to implement and convenient to operate, can continuously produce, is suitable for long-period operation, and is easy to popularize and use only by additionally arranging the booster pump and the corresponding connecting pipeline thereof.
Drawings
FIG. 1 is a schematic flow diagram of a production unit for reducing the COD content in the waste water discharged from a cyclohexanone device;
wherein, 1 is a cyclohexanone tower, 2 is a cyclohexanol tower, 3 is a condensate recovery tank, 4 is a booster pump, 5 is a decomposition reaction kettle, 11 is a cyclohexanone tower vacuum pumping system, 21 is a cyclohexanol tower vacuum pumping system, 31 is a gas phase vent, 32 is an organic phase outlet, 33 is a water phase outlet, and 41 is a pipeline from the booster pump to the decomposition reaction kettle.
Detailed Description
The following specific examples are intended to further illustrate the invention in conjunction with the accompanying drawings and are not intended to limit the scope of the invention as claimed.
The flow diagram of the production unit for reducing the COD content in the waste water discharged from the cyclohexanone device is shown in figure 1.
The process for reducing the COD content in the waste water discharged from the cyclohexanone device comprises the following steps: carrying out alcohol ketone organic phase and water phase settlement separation on the condensed fluid pumped by the cyclohexanone tower/cyclohexanol tower in a condensed fluid recovery tank; and discharging the water phase from the bottom of the condensate recovery tank, discharging the alcohol ketone organic phase from the top of the condensate recovery tank, and pumping the water phase and the alcohol ketone organic phase into the decomposition reaction kettle through a booster pump. In the reaction kettle, the organic phase can extract the organic matters in the water phase, then the water phase is separated from the organic phase, and the water phase is subjected to one-step waste alkali evaporation, so that the quality of the recovered condensate can be greatly improved, the consumption of the internal circulation process water is greatly reduced, the wastewater yield is reduced, and the COD content in the wastewater discharged in the steam stripping process is reduced.
Example 1
A device for producing 8.0 ten thousand tons of cyclohexanone in a certain year, and the ventilation capacity is about 13200Nm3And h, the condensate pumped by the cyclohexanone tower/cyclohexanol tower is about 2t/h, and the organic content is 5.67%. The technical scheme of the invention is adopted to treat the condensed liquid of the cyclohexanone tower/cyclohexanol tower after vacuum pumping, and the COD content in the waste water discharged from the steam stripping process is 2159 mg/L.
Comparative example 1
The traditional process is adopted for treatment, the organic phase of the condensate recovery tank is subjected to material ejection by process water, recovered by a vacuum pump and sent to a saponification system by a pump, the operation method increases the labor intensity of operators, and when the vacuum pump is used for recovering materials, part of organic materials run into the atmosphere through a gas phase pipeline to pollute the environment. The water phase is sent to a waste water stripping tower by a pump for stripping, organic alcohol ketone in the inorganic phase is recovered as much as possible, the condensate pumped by the cyclohexanone tower/cyclohexanol tower in vacuum is about 2.1t/h, the content of organic matters is 5.87%, the COD content in the waste water discharged outside the stripping process is 19590mg/L, and the waste water is sent to an environment-friendly device for treatment.
Claims (6)
1. A method for reducing COD content in waste water discharged from a cyclohexanone device is characterized in that: on the premise of ensuring the water sealing function of the condensate recovery tank, the condensate of the condensate recovery tank is continuously or discontinuously pumped into the decomposition reaction kettle by arranging the booster pump.
2. The method for reducing the COD content in the wastewater discharged by the cyclohexanone device according to claim 1, which is characterized in that: and the upper organic phase is ejected out to an inlet of a booster pump through the condensate of the self-body or the supplemented process water entering a condensate tank.
3. The method for reducing the COD content in the wastewater discharged by the cyclohexanone device according to claim 1, which is characterized in that: and a baffle is arranged in the condensate recovery tank.
4. The method for reducing the COD content in the wastewater discharged by the cyclohexanone device according to claim 1, which is characterized in that: the gas phase vent of the condensate recovery tank is higher than the organic phase outlet by more than 100 mm.
5. The method for reducing the COD content in the wastewater discharged by the cyclohexanone device according to claim 1, which is characterized in that: the outlet pipeline of the booster pump is directly connected with the decomposition reaction kettle body; or is connected with an oxidation liquid pipeline entering the decomposition reaction kettle.
6. The method for reducing the COD content in the wastewater discharged by the cyclohexanone device according to claim 1, which is characterized in that: the condensate is cyclohexanone/cyclohexanol vacuumizing condensate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811179210.6A CN111018214B (en) | 2018-10-10 | 2018-10-10 | Method for reducing COD content in waste water discharged from cyclohexanone device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811179210.6A CN111018214B (en) | 2018-10-10 | 2018-10-10 | Method for reducing COD content in waste water discharged from cyclohexanone device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111018214A true CN111018214A (en) | 2020-04-17 |
| CN111018214B CN111018214B (en) | 2023-02-03 |
Family
ID=70191829
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811179210.6A Active CN111018214B (en) | 2018-10-10 | 2018-10-10 | Method for reducing COD content in waste water discharged from cyclohexanone device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111018214B (en) |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101428915A (en) * | 2008-07-13 | 2009-05-13 | 赵志军 | Method for zero discharge processing of waste saponification lye of cyclohexanone produced by cyclohexane oxidation technology |
| CN103274568A (en) * | 2013-05-30 | 2013-09-04 | 湖南百利工程科技股份有限公司 | Method for treating ketone-containing wastewater in cyclohexanone ammoximation device by employing extraction method |
| CN204234103U (en) * | 2014-11-10 | 2015-04-01 | 山东新港化工有限公司 | A kind of catalyst feed reclaimer for the production of o-phenyl phenol |
| CN104909984A (en) * | 2015-06-10 | 2015-09-16 | 中国天辰工程有限公司 | Method for recycling cyclohexanol from cyclohexanone device waste liquid |
| CN205398514U (en) * | 2016-03-10 | 2016-07-27 | 湖南百利工程科技股份有限公司 | Cyclohexanone refining plant in cyclohexanone production process |
| CN106362548A (en) * | 2016-10-10 | 2017-02-01 | 湖南百利工程科技股份有限公司 | Treating method of oxidized tail gas in process of manufacturing cyclohexanone with cyclohexane oxidation method |
| CN107540523A (en) * | 2016-06-28 | 2018-01-05 | 中国石油化工股份有限公司 | A kind of method for reducing sodium salt content in the ketone material of crude glycol containing alkali lye |
| CN107778133A (en) * | 2016-08-25 | 2018-03-09 | 中国石油化工股份有限公司 | A kind of method for preparing cyclohexanol and cyclohexanone |
| CN108530317A (en) * | 2018-06-01 | 2018-09-14 | 宋心红 | A kind of oximate device heat energy utilization system and utilize method |
| CN108558629A (en) * | 2018-06-01 | 2018-09-21 | 李洪震 | A kind of production system and production method of refined cyclohexanone |
-
2018
- 2018-10-10 CN CN201811179210.6A patent/CN111018214B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101428915A (en) * | 2008-07-13 | 2009-05-13 | 赵志军 | Method for zero discharge processing of waste saponification lye of cyclohexanone produced by cyclohexane oxidation technology |
| CN103274568A (en) * | 2013-05-30 | 2013-09-04 | 湖南百利工程科技股份有限公司 | Method for treating ketone-containing wastewater in cyclohexanone ammoximation device by employing extraction method |
| CN204234103U (en) * | 2014-11-10 | 2015-04-01 | 山东新港化工有限公司 | A kind of catalyst feed reclaimer for the production of o-phenyl phenol |
| CN104909984A (en) * | 2015-06-10 | 2015-09-16 | 中国天辰工程有限公司 | Method for recycling cyclohexanol from cyclohexanone device waste liquid |
| CN205398514U (en) * | 2016-03-10 | 2016-07-27 | 湖南百利工程科技股份有限公司 | Cyclohexanone refining plant in cyclohexanone production process |
| CN107540523A (en) * | 2016-06-28 | 2018-01-05 | 中国石油化工股份有限公司 | A kind of method for reducing sodium salt content in the ketone material of crude glycol containing alkali lye |
| CN107778133A (en) * | 2016-08-25 | 2018-03-09 | 中国石油化工股份有限公司 | A kind of method for preparing cyclohexanol and cyclohexanone |
| CN106362548A (en) * | 2016-10-10 | 2017-02-01 | 湖南百利工程科技股份有限公司 | Treating method of oxidized tail gas in process of manufacturing cyclohexanone with cyclohexane oxidation method |
| CN108530317A (en) * | 2018-06-01 | 2018-09-14 | 宋心红 | A kind of oximate device heat energy utilization system and utilize method |
| CN108558629A (en) * | 2018-06-01 | 2018-09-21 | 李洪震 | A kind of production system and production method of refined cyclohexanone |
Non-Patent Citations (1)
| Title |
|---|
| 申武: "环己烷-水萃取法处理环己酮废水", 《合成纤维工业》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111018214B (en) | 2023-02-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110606799B (en) | System and method for recycling byproduct of propylene oxide production by HPPO method | |
| CN109503410B (en) | Method for recovering DMF (dimethyl formamide) solvent in sucralose production | |
| CN102887815B (en) | N-propanol refining technology | |
| CN104628664A (en) | Method for continuously producing benzotriazole | |
| CN101088975A (en) | Fuel alcohol dewatering apparatus and process | |
| CN110698325A (en) | Production device and process for co-producing fuel ethanol and special grade edible alcohol | |
| CN108002995B (en) | Method and equipment for synthesizing methyl isobutyl ketone by acetone two-step method | |
| CN202038998U (en) | Production system for recycling carbolic oil through acidolysis separation of phenol sodium salt and co-producing sodium sulfite | |
| CN112142618B (en) | Low-concentration dimethylformamide wastewater recovery system and method | |
| CN111018214B (en) | Method for reducing COD content in waste water discharged from cyclohexanone device | |
| CN110655259B (en) | Coal chemical wastewater extraction dephenolization recycling treatment process | |
| CN103814008A (en) | Device and method for separating off water and recovering carboxylic acid from reactor discharge during aromatic compound oxidation reaction using energy donating coupled distillation | |
| CN107879314A (en) | A kind of bromine recovery method for the brominated waste water for producing diafenthiuron | |
| CN107337308B (en) | Device and process for extracting glycerin from epoxy resin device high-salinity wastewater concentrated solution | |
| CN209383430U (en) | Spent caustic treatment device in a kind of cyclohexanone preparation process | |
| CN209302215U (en) | A kind of device vacuumizing condensate liquid for recycling cyclohexanone tower/cyclohexanol tower | |
| CN107540523B (en) | Method for reducing sodium salt content in crude alcohol ketone material containing alkali liquor | |
| CN210786817U (en) | Device for recovering effective components of rectification residues and comprehensively treating waste gas in polyvinyl alcohol production process | |
| CN107129103B (en) | Comprehensive treatment and utilization process and method for furfural production wastewater | |
| CN211170278U (en) | Coal chemical wastewater extraction dephenolization resourceful treatment system | |
| CN101973847A (en) | Method for extracting mixture of butyraldehyde, butanol, octenal and octanol from waste liquid discharged by butanol-octanol device | |
| CN206109253U (en) | Thick alcohol ketone material demineralizer | |
| CN116354809B (en) | Method for treating and reutilizing tail gas from butyric acid production | |
| CN108358874B (en) | Multi-section production method and device for diketene | |
| CN211753722U (en) | Pressure reduction and methanol recovery integrated device for production of esterification hydrogenation products |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |