CN1354165A - Control of waste water produced in furfural industry and preparation process of butyl acetate - Google Patents
Control of waste water produced in furfural industry and preparation process of butyl acetate Download PDFInfo
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- CN1354165A CN1354165A CN 01133449 CN01133449A CN1354165A CN 1354165 A CN1354165 A CN 1354165A CN 01133449 CN01133449 CN 01133449 CN 01133449 A CN01133449 A CN 01133449A CN 1354165 A CN1354165 A CN 1354165A
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- furfural
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Abstract
The process for treating waste water or furfural industry includes the following steps: filtering the waste water of furfural industry, cooling it by means of heat exchanger, pumping it into double-chamber floating ion excahnger in which the macroporous strong base and weak base ion exchange resins are held to make treatment; making acetic acid radical and furfural exchange with exchange base function group and be adsorbed on the resin, using ammonia water to make desorption operation and desorbing furfural with small affinity to obtain liquid mixture of furfural and ammonia water; then desorbing acetic acid radical ion with large affinity, making it react with ammonia water to produced ammonium acetate solution, respectively making evaporation and concentration, and refining treatment to respectively obtain furfural and butyl acetate.
Description
Technical field
The present invention relates to a kind of industrial wastewater from furfural production New Method for Processing, particularly a kind of control of waste water produced in furfural industry and preparation N-BUTYL ACETATE technology.
Background technology
At present, because furfural is an important chemical material, so furfural mill has become widely distributed leading enterprise in all parts of the country.Especially the staple crop of China the Northeast is a corn, and corn cob is a good raw material of producing furfural, and therefore, there are nearly 70 tame furfural mills the Northeast.These enterprises continue to use production technique for many years, earlier the piperylene in the corn cob are hydrolyzed into pentose with sulfuric acid catalysis, and further dehydration prepares furfural again.In hydrolytic process, take furfural and other by-product volatile matter that hydrolysis produces out of hydrolyzer with high-pressure steam, form aldehyde gas.Generally contain furfural 4-6% in the aldehyde gas, acetic acid 1-2% also has a small amount of low-boiling-point substance.Aldehyde gas enters primary tower after condensation, obtain furfural and water azeotrope at cat head, discharges the trade effluent that contains acetic acid and a small amount of furfural at the bottom of the primary tower.Because of its technology imperfection, the waste water at the bottom of making acetic acid with the fore-running Tata has been arranged and has been gone out.Industrial wastewater from furfural production generally all is untreated and directly discharging, confirms that through environmental monitoring results the acetic acid mean concns is 1.5%, and the concentration of furfural is according to the equipment difference of each furfural mill difference to some extent, but roughly about 0.1%.This not only causes environmental pollution, and has wasted precious water resource and industrial chemicals acetic acid in short supply.Existing enterprise solves the main method of industrial wastewater from furfural production to be had:
(1) anaerobe is administered method: this method has high input, the working cost height.Its maximum shortcoming is that process control condition is required harshness, and is high excessively as temperature control requirement, is not suitable for very much the industrial sewage of the Northeast's furfural mill is handled.Liaoning furfural mill was once administered trade effluent with this method, invested more than 90 ten thousand yuan, because of guaranteeing the survival condition of microorganism, never obtained the ideal regulation effect.
(2) extraction process extracts acetic acid: this method investment is bigger, and extraction agent easily poisons because of furfural disturbs, that is the regeneration difficulty, applies so influence it.
(3) phase transfer method extracts acetic acid: this method has very much progress than preceding two kinds of methods, uses the phase transition tripping device that sorbent material is housed, from aqueous phase with acetic acid and water sepn to organic phase.Become to contain organic concentrated solution of acetic acid through evaporation concentration, re-use this concentrated solution and ethanol synthesis generation ethyl acetate.But practical application shows that also there are many problems in this method.Wherein topmost problem is that the consisting of phase-transferring agent loading capacity is little, makes that the acetic acid in the waste water does not shift out from aqueous phase fully, and has entered in the boiler recirculated water.Though to not influence of boiler, most of resource has been wasted, and is unfavorable for the popularization of project.Acetic acid extraction rate in the waste water low (less than 50%), separating effect is relatively poor.As implementing this method at the Jilin furfural mill, the organic concentrated solution produced and standard output, promptly the content of acetic acid in the output of acetic acid and the waste water differs hundreds of times, and the ratio that contains acetic acid in the concentrated solution that obtains is no more than 7% at most.Compare with design load (＞40%) because of it, gap is too big, can not reach the concentrated effect of design.Acetate concentration does not reach the production that standard just can't be carried out follow-up second vinegar second fat in organic concentrated solution.
In sum, many furfural mills all do not have ideal industrial wastewater treatment technology.Whole nation furfural enterprise is subjected to the pressure of ecocrisis deeply, and urgent hope solves this puzzlement control of waste water produced in furfural industry difficult problem for a long time.Therefore, an improvement difficult problem that solves industrial wastewater from furfural production not only is related to environmental issue, more is related to the furfural industry survival and development in future.
Summary of the invention
The purpose of this invention is to provide a kind of control of waste water produced in furfural industry and preparation process of butyl acetate, sufficient, the low price in the raw materials used source of this processing method, compare with other ion exchange method water technologies, separating effect is remarkable, process flow operation is stable, easy to operate, up system water, descending regeneration, it is good to have in the counter-current regeneration technology resin regeneration effect and effluent quality, and regenerative process has the characteristics of co-current regeneration technology again.Its regenerator utilization ratio height, regeneration consumable water consumption is low, water saving.
The object of the present invention is achieved like this: earlier industrial wastewater from furfural production is filtered, cool to 50-60 ℃ through interchanger, pump into then that macropore is housed is strong, handle in the unsteady ion-exchanger in two chambers of weak-base ion-exchange resin, the exchange group functional group exchange of acetate and furfural and ion exchange resin, be adsorbed on the ion exchange resin, the water ph value of the feasible ion-exchanger outlet of floating is between 6-8, when pH value is lower than 6, and when reducing rapidly, carry out desorption manipulation immediately, use the ammoniacal liquor of the concentration of industrial wastewater from furfural production amount 10% as 5-10%, ion exchange resin is carried out desorption, the furfural that avidity is little is got off by desorption earlier, obtains the mixed solution of furfural and ammoniacal liquor and ammonium acetate; Add excessive ammonia then, the bigger acetate ion desorption of avidity is got off, generate the intermediates Spirit of Mindererus with the ammoniacal liquor reaction, distinguish evaporation concentration again, further refinement treatment is then separately won furfural and acetic acid.
In the above-mentioned pair of unsteady ion-exchanger in chamber, macroporous strong basic ion exchange resin is equipped with in last chamber, and macroreticular weakly base ion exchange resin is equipped with in following chamber.
The mixed solution of above-mentioned isolated furfural and ammoniacal liquor and ammonium acetate carries out vacuum distilling to be handled, and ammonia that steams and water are made into 10% ammoniacal liquor again and recycle after vacuum pump absorbs, and remaining hair aldehyde enters primary tower and distills again, reclaims furfural.
Above-mentioned isolated intermediates Spirit of Mindererus distills processing, when concentration is 40-50%, is the vitriol oil acidifying of 90-98% with concentration, and pH value reaches 1-2, makes ammonium acetate and sulfuric acid complete reaction generate the mixture of ammoniumsulphate soln and acetic acid.
Mixture to above-mentioned ammoniumsulphate soln and acetic acid evaporates again, will acetic acid obtain ammonia sulfate crystal after the distillation, and the acetic acid that evaporate away carries out conventional esterification reaction generation acetate butyl with butanols after putting into the reactor internal cooling.
Because it is exactly that slightly acidic is all arranged that acetic acid in the furfural waste-water and furfural have a something in common.Acetic acid is weak organic acid; And furfural is because the skew of its electronic cloud, one of them hydrogen atom is also lost easily, so very weak acidity is also arranged, macropore is strong, the unsteady ion-exchanger of weak-base ion-exchange resin so the present invention's use is equipped with, adopt ion exchange method to replace phase transfer method that furfural waste-water is handled, from waste water, extract acetic acid and furfural.This processing method is according to the difference of acetic acid and furfural acidity (losing H ion ability), the affinity that makes full use of deacidite Dichlorodiphenyl Acetate and furfural is different, under the effect of the macropore deacidite in the ion-exchanger that floats, exchange group functional group exchange with acetate and furfural and resin, be adsorbed on the resin, only contain the low-boiling-point organic compound of trace in the treating water that makes unsteady ion-exchanger export, and do not contain acetic acid and furfural.The treating water of this outlet after active carbon column filters decolouring, meets the boiler feed water requirement more fully, can enter the boiler circulating water line.And in the water low-boiling-point organic compound of trace in boiler with infiltrate the reaction of ducted minor amounts of oxygen, discharge with boiler gas oxidized back.Because these low-boiling-point organic compounds have consumed partial oxygen, have also just reduced the oxidation corrosion of boiler, help the work-ing life of prolonged boiler.
The present invention adopts ion exchange method not only can realize separating of acetic acid and furfural and water in the waste water, can also realize separating of acetic acid and furfural.Macropore is strong, weak-base ion-exchange resin has than the better separating effect of consisting of phase-transferring agent furfural in the waste water and acetic acid, and price is more cheap, the source is more sufficient.Be utilization ratio, the reduction equipment work pressure that improves ion exchange resin, adopt the unsteady ion-exchanger in two chambers.Phase transition post in the existing phase transfer method is Φ 1.6 * 7M carbon steel lining plastic structure, and its manufacturing cost height is installed, transports also very difficult.And the unsteady ion-exchanger in two chambers can adopt the plain carbon stool line with rubber, also can adopt the ABS engineering plastics, and size only is Φ 0.8 * 3M.This device all pipelines except that the interchanger gangway all replace stainless steel pipeline commonly used with the ABS engineering plastics, greatly reduce manufacturing cost, and install, transport also very convenient.In addition consisting of phase-transferring agent manufacturer seldom, (50,000 yuan/ton) cost an arm and a leg; And ion exchange resin is common Chemicals, and manufacturer in all parts of the country is numerous, and price is about 20,000 yuan/ton.Use the every covering device of consisting of phase-transferring agent to need 6 tons, price is 300,000 yuan; And ion exchange resin only needs 4 tons, and expense is no more than 100,000 yuan.Strong type resin-be macroporous strong basic ion exchange resin is loaded in float the last chamber of ion-exchanger, two chambers, pretend to be fragile type resin-be macroreticular weakly base ion exchange resin of following chamber.In ion-exchanger is floated in two chambers, two kinds of resins the other side that respectively does for oneself provides favourable working conditions, be that the weak type resin provides high regeneration level for the strong type resin, thereby improved the operating capacity of strong type resin, and the strong type resin allows the weak type resin that higher leakage is arranged, given full play to the speciality of weak type resin, like this with high regeneration efficiency, the weak type of high regenerated capacity and the strong and weak type resin combined utilization of working under high regeneration level deacidify in the chemistry of water, can be under the regeneration specific consumption of 1.0-1.3, the average operating capacity of anionresin technology reaches 600～900mmol/LR, and this is that other technology institute is inaccessible.The up system water of this technology, descending regeneration, it is good to have in the counter-current regeneration technology resin regeneration effect and effluent quality, and regenerative process has co-current regeneration technology again, easy-operating characteristics.
The present invention compares with other ion exchange method water technologies, and it is good to have an effluent quality, regenerator utilization ratio height, and regeneration consumable water consumption is low, equipment and resin utilization ratio height, the operation flow velocity is fast, the advantage of water quality wide adaptability, water saving.The present invention also can be widely used in water desalination, softening water and some ionic and remove the place, and every profession and trade can be used per family to the demanding usefulness of quality.
Description of drawings
Below in conjunction with accompanying drawing technical process equipment therefor of the present invention is described.
Fig. 1 is a kind of concrete structure synoptic diagram of the unsteady ion-exchanger in the two chambers of the present invention.
Shown in the figure, 1 water outlet, 2 viewing windows, 3 manholes, 4 sieve plates, 5 viewing windows, 6 housings, 7 water inlets.Ion-exchanger (Shuande, Guangdong Province city converge many chemical machineries Manufacturing Co., Ltd produce) floats the used pair of chamber in the embodiment of the invention, physical dimension is Φ 0.8 * 3M, the middle is the sieve plate of a Φ 0.8M, and sieve plate is with 100 order stainless (steel) wire overspreads, in order to avoid resin sees through.The sieve plate hole total area is 0.28m
2(the aperture type of sieve plate shape is not limit, but is not less than 0.28m
2).The resin floor height is 1.2M.Strong, the weak-base ion-exchange resin of filling macropore in the said apparatus (Dandong No.3 Chemical Factory produces, if when dispatching from the factory be the chlorine type to carry out ammonification, keep that promptly excess of ammonia is arranged in the interchanger, make its pH value be about 9.Last chamber filling D201 macropore highly basic styrene series anion exchange resin, following chamber filling D301 macropore weak base styrene series anion exchange resin).
Used butanols adopts the mixture (Jilin Petroleum chemical plant, Daqing Petrochemical factory produce) of commercially available prod or butanols and octanol, about 500 yuan/ton of price.Because butanols is different with the octanol boiling point, use Φ 0.8 * 30M material filling type distillation tower that it is separated, butanols is used for fatization, and octanol is used as the raw material of other products.
Embodiment
Below in conjunction with embodiment technical process of the present invention is described in detail.
Embodiment one
With trade effluent under the furfural mill primary tower through 15m
2Behind the stainless heat exchanger, it is cooled to 55-60 ℃, and flow into certainly in the surge tank.Through acid proof pump with 4m
3The flow velocity of/h pumps into the inlet of the unsteady ion-exchanger below from two chambers of the water in the surge tank.The exchange group functional group exchange of acetate in the waste water and furfural and ion exchange resin, adsorbed by ion exchange resin, neutral water (pH value is 6～8) is discharged in the unsteady ion-exchanger outlet in two chambers continuously, and the time length is approximately 8 hours, and getting the neutral water yield is 32 tons.Inlet COD value is greater than 10000, and outlet is 700～800.When the water ph value of its outlet is lower than 6, and when reducing rapidly, with the concentration of industrial wastewater from furfural production amount 10% is that 10% weak ammonia carries out desorption, flow velocity is 2 tons/hour, through 80 minutes, the PH of unsteady ion-exchanger below, two chambers water inlet approximates 9, and acid group and the furfural that adsorb on the resin this moment are all changed by functional group, should stop desorption immediately.Was the furfural desorption in desorption ph value in early stage less than 6.2 o'clock, and 6.2～6.5 o'clock is furfural and the common desorption of acetic acid, forms furfural and ammoniacal liquor and ammonium acetate mixed solution.Add excessive ammonia afterwards, the bigger acetate ion desorption of avidity is got off, generate the intermediates Spirit of Mindererus with the ammoniacal liquor reaction.
For guaranteeing the quality of ammonium acetate, with the ph value of mixture of isolated furfural and ammoniacal liquor and ammonium acetate less than 6.5 effluent liquid, flow into relay tank earlier, treat that accumulative total reaches three ton hours, squeeze in the evaporating kettle with pump again, carry out vacuum distilling and handle, ammonia that steams and water are made into 10% ammoniacal liquor again and recycle after vacuum pump absorbs, remaining hair aldehyde enters primary tower and distills again, reclaims furfural.
The said process repeatable operation can obtain meeting the neutral water of boiler feed water standard.For making the operate continuously of this technology, can adopt 2 unsteady ion-exchanger exchanges in two chambers to use.
Embodiment two
When above-mentioned furfural, ammoniacal liquor and ammonium acetate mixed solution evaporated, in order to raise the efficiency the saving cost, we adopted aldehyde gas heating under vacuum method.Vacuum pump adopts liquid-jet vacuum pump.When using this water of constitution pump motor as the 1.5KW motor, mixed solution is 95C ° of i.e. boiling.And ammonia that steams and water send test tank to prepare configuration 10% ammoniacal liquor after the absorption of the cold water in the pipeline and being cooled to room temperature immediately.Present method improves vaporization efficiency, the ammonia loss is few, but also has saved an interchanger.
Embodiment three
Above-mentioned isolated intermediates Spirit of Mindererus distills processing by embodiment two modes.When concentration is 40-50%, be the vitriol oil acidifying of 90-98% with concentration, pH value reaches 1-2, makes ammonium acetate and sulfuric acid complete reaction generate the mixture of ammoniumsulphate soln and acetic acid.Close vacuum pump and continue to be distilled to ammonia sulfate crystal and separate out, the ammonium sulfate saturated solution.Promptly obtain residual product ammonia sulfate crystal of still and the dilute solution that contains small amount of ammonium sulfate, acetic acid after the suction filtration cooling, dilute solution is squeezed into evaporating kettle recycle.The gas that evaporates is acetic acid, carries out conventional esterification reaction generation product acetate butyl with butanols to another reactor internal cooling.
Claims (5)
1, a kind of control of waste water produced in furfural industry technology, it is characterized in that earlier industrial wastewater from furfural production being filtered, be cooled to 50-60 ℃ through interchanger, pump into then that macropore is housed is strong, handle in the unsteady ion-exchanger in two chambers of weak-base ion-exchange resin, the exchange group functional group exchange of acetate and furfural and ion exchange resin, be adsorbed on the ion exchange resin, make the water ph value of ion-exchanger outlet between 6-8, when pH value is lower than 6, and when reducing rapidly, carry out desorption manipulation immediately, use the ammoniacal liquor of the concentration of industrial wastewater from furfural production amount 10% as 5-10%, ion exchange resin is carried out desorption, and the furfural that avidity is little is got off by desorption earlier, obtains the mixed solution of furfural and ammoniacal liquor; Add excessive ammonia then, the bigger acetate ion desorption of avidity is got off, generate the intermediates Spirit of Mindererus with the ammoniacal liquor reaction, distinguish evaporation concentration again, further refinement treatment is then separately won furfural and acetic acid.
2, technology according to claim 1 is characterized in that in the above-mentioned ion-exchanger, macroporous strong basic ion exchange resin is equipped with in last chamber, and macroreticular weakly base ion exchange resin is equipped with in following chamber.
3, technology according to claim 1, the mixed solution that it is characterized in that isolated furfural and ammoniacal liquor and ammonium acetate carries out the vacuum distilling processing, ammonia that steams and water are made into 10% ammoniacal liquor again and recycle after vacuum pump absorbs, remaining hair aldehyde, enter primary tower and distill again, reclaim furfural.
4, technology according to claim 1, it is characterized in that isolated intermediates Spirit of Mindererus distills processing, when concentration is 40-50%, with concentration is the vitriol oil acidifying of 90-98%, pH value reaches 1-2, makes ammonium acetate and sulfuric acid complete reaction generate the mixture of ammoniumsulphate soln and acetic acid.
5, technology according to claim 4, it is characterized in that the mixture of ammoniumsulphate soln and acetic acid is evaporated again, will acetic acid obtain ammonia sulfate crystal after the distillation, the acetic acid that evaporate away carries out conventional esterification reaction generation acetate butyl with butanols after putting into the reactor internal cooling.
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| CN 01133449 CN1354165A (en) | 2001-11-15 | 2001-11-15 | Control of waste water produced in furfural industry and preparation process of butyl acetate |
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| CN 01133449 CN1354165A (en) | 2001-11-15 | 2001-11-15 | Control of waste water produced in furfural industry and preparation process of butyl acetate |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100374378C (en) * | 2006-05-19 | 2008-03-12 | 高武 | Treatment process for recovering industrial wastewater from producing furfural |
| CN102125803A (en) * | 2010-12-10 | 2011-07-20 | 北京科技大学 | Method for purifying degraded amine solution |
| CN103214439A (en) * | 2013-04-09 | 2013-07-24 | 浙江台州清泉医药化工有限公司 | Method for separating and purifying furfural |
| CN111285764A (en) * | 2019-01-14 | 2020-06-16 | 广东博兴新材料科技有限公司 | Treatment method for recycling (methyl) acrylic acid in esterification reaction system |
| CN111689635A (en) * | 2020-06-10 | 2020-09-22 | 南京工业大学 | Method for treating waste water containing ammonium acetate |
| CN111689857A (en) * | 2020-05-18 | 2020-09-22 | 南京工业大学 | Resource utilization method of ethyl acetate production wastewater |
-
2001
- 2001-11-15 CN CN 01133449 patent/CN1354165A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100374378C (en) * | 2006-05-19 | 2008-03-12 | 高武 | Treatment process for recovering industrial wastewater from producing furfural |
| CN102125803A (en) * | 2010-12-10 | 2011-07-20 | 北京科技大学 | Method for purifying degraded amine solution |
| CN102125803B (en) * | 2010-12-10 | 2013-05-01 | 北京科技大学 | Method for purifying degraded amine solution |
| CN103214439A (en) * | 2013-04-09 | 2013-07-24 | 浙江台州清泉医药化工有限公司 | Method for separating and purifying furfural |
| CN103214439B (en) * | 2013-04-09 | 2016-03-02 | 江苏清泉化学股份有限公司 | A kind of method of separating-purifying furfural |
| CN111285764A (en) * | 2019-01-14 | 2020-06-16 | 广东博兴新材料科技有限公司 | Treatment method for recycling (methyl) acrylic acid in esterification reaction system |
| CN111689857A (en) * | 2020-05-18 | 2020-09-22 | 南京工业大学 | Resource utilization method of ethyl acetate production wastewater |
| CN111689857B (en) * | 2020-05-18 | 2023-03-17 | 南京工业大学 | Resource utilization method of ethyl acetate production wastewater |
| CN111689635A (en) * | 2020-06-10 | 2020-09-22 | 南京工业大学 | Method for treating waste water containing ammonium acetate |
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