It is a kind of to improve crystallization purity salt and resource rate divides salt system and methodTechnical field:
Crystallization purity salt is improved and resource rate divides salt system and method the present invention relates to a kind of, belongs to wastewater treatment neckDomain.The high saliferous industrial wastewater especially generated in coal chemical industry enterprises production process improves high saliferous industrial wastewater sub-prime salt zeroThe crystal salt yield of discharge process technique.
Background technique:
High saliferous industrial wastewater, especially coal chemical industry enterprises were waited in coal oil, ammonia from coal, coal-to-olefin, coal gasThe waste water generated in journey has the characteristics that salt content is high, hardness is high, COD content is high and biochemical is poor.
In numerous high saliferous industrial wastewater sub-prime salt Zero discharge treatment methods, two fraction salt that nanofiltration is coupled with thermal methodMethod obtains the approval of insider and industry specialists, and nanofiltration divides salt, is by monovalent ion using Nanofiltration-membrane technique (with Cl-ForIt is main) and divalent ion (with SO42-Based on) separate, the solution based on monovalent ion and the solution based on divalent ion are formed,The two is evaporated respectively carries out a point salt；Thermal method divides salt, is to carry out a point salt using the changing rule of various salt solubilities.In actual motionIn the process, both crystallization purity salts for dividing salt method to separate substantially meet industrial salt requirement, but crystal salt yield is insufficient55%, generate a large amount of carnallites.This part carnallite is named as hazardous waste and is disposed, and increases environmental protection of enterprise pressure and waste waterProcessing cost.Therefore, crystal salt yield is improved, carnallite amount is reduced, becomes high saliferous industrial wastewater sub-prime salt zero discharge treatment workThe key of skill.
Summary of the invention:
The first purpose of this invention is to provide a kind of point salt system for improving crystallization purity salt and resource rate.
Second object of the present invention be to provide it is a kind of improve crystallization purity salt and resource rate divide salt method.
The first purpose of this invention is implemented by following technical solution: a kind of point improving crystallization purity salt and resource rateSalt system comprising nanofiltration conditioning tank, nano-filtration unit, NaCl depth upgrading unit, NaCl evaporative crystallization unit, organic matter degradationUnit, Na2SO4Depth upgrading unit, Na2SO4Evaporative crystallization unit and dissolving tank；
The nanofiltration conditioning tank respectively with the nano-filtration unit, the organic matter degradation unit, the Na2SO4Depth concentrationUnit is connected by pipeline, is equipped with the first shut-off valve on the pipeline for being connected to the nanofiltration conditioning tank and the nano-filtration unit,The pipeline for being connected to the nanofiltration conditioning tank and the organic matter degradation unit is equipped with the second shut-off valve, is being connected to the nanofiltration tuneSave pond and the Na2SO4The pipeline of depth upgrading unit is equipped with third shut-off valve；
The nano-filtration unit is connect with the NaCl depth upgrading unit, the NaCl depth upgrading unit and the NaClEvaporative crystallization unit is connected by pipeline；
The organic matter degradation unit respectively with the Na2SO4Depth upgrading unit and the Na2SO4Evaporative crystallization unitIt is connected by pipeline, is being connected to the organic matter degradation unit and the Na2SO4The pipeline of depth upgrading unit is equipped with the 4thShut-off valve is being connected to the organic matter degradation unit and the Na2SO4The pipeline of evaporative crystallization unit is equipped with the 5th shut-off valve；The Na2SO4Depth upgrading unit and the Na2SO4Evaporative crystallization unit is connected by pipeline, is being connected to the Na2SO4DepthUpgrading unit and the Na2SO4Pipeline between evaporative crystallization unit is equipped with the 6th shut-off valve；The Na2SO4Evaporative crystallizationThe mixed salt outlet of unit is connect with the dissolving tank, and the dissolving tank is logical with the nanofiltration conditioning tank and the nano-filtration unit respectivelyPiping connection is equipped with the 7th shut-off valve on the pipeline for being connected to the dissolving tank and the nanofiltration conditioning tank, described in connectionDissolving tank and the pipeline of the nano-filtration unit are equipped with the 8th shut-off valve；
The nano-filtration unit respectively with the organic matter degradation unit, the Na2SO4Depth upgrading unit is connected by pipelineIt connects, the 9th shut-off valve is equipped on the pipeline being connected between the nano-filtration unit and the organic matter degradation unit, in connection instituteState nano-filtration unit and the Na2SO4Pipeline between depth upgrading unit is equipped with the tenth shut-off valve.
Nano-filtration unit of the present invention, can be according to the height of intake total dissolved solid, chloride ion, sulfate radical isoconcentrationDetermine the combining form of nano-filtration unit.It can be one or more levels nanofiltration, can be one or more snippets nanofiltration, be also possible to level-oneMultistage, one section of multistage or multistage multistage nanofiltration combination；
NaCl depth upgrading unit and Na of the present invention2SO4Depth upgrading unit can be high-pressure flat plate film(DTRO), electrodialysis (ED), efficiently (high pressure) reverse osmosis, positive permeation unit etc., are also possible to the combination of above-mentioned a few persons.
Organic matter degradation unit of the present invention can be with catalytic ozonation technology, electro-catalytic oxidation technology, surpassTechnology of acoustic wave, plasma technology, light electrolysis-Fenton technology, supercritical oxidation, activated carbon adsorption, macroporous resin adsorption unit,It can be the combination of above-mentioned a few persons.
NaCl evaporative crystallization unit and Na of the present invention2SO4It is single to can be single effect evaporation crystallization for evaporative crystallization unitMember, multiple-effect evaporation crystalline element, MVR evaporative crystallization unit etc., are also possible to the combination of above-mentioned a few persons.
Second object of the present invention is implemented by following technical solution: a kind of point improving crystallization purity salt and resource rateSalt method, high saliferous industrial wastewater after pretreatment are discharged into the quenched tune amount of nanofiltration conditioning tank, then according to described high containing salt workerC (Cl in industry waste water-): c (SO42-), the specific processing method of high saliferous industrial wastewater is selected, is specifically included:
(1) as c (Cl in the high saliferous industrial wastewater-): c (SO42-) >=1:2, opens the first shut-off valve, and the height containsSalt industrial waste water enters nano-filtration unit and carries out nanofiltration point salt treatment, obtains nanofiltration and produces water and nanofiltration concentrated water；The nanofiltration produce water according toIt is secondary to be evaporated crystallization into NaCl depth upgrading unit progress depth concentration, NaCl evaporative crystallization unit, obtain NaCl crystal；
According to the TDS content of the nanofiltration concentrated water, the specific processing method of the nanofiltration concentrated water is selected, is specifically included:
(1.1) as TDS >=100000mg/L of the nanofiltration concentrated water, the 9th shut-off valve, the 5th shut-off valve and the 7th are openedShut-off valve, the nanofiltration concentrated water sequentially enter organic matter degradation system and carry out organic matter degradation, Na2SO4Evaporative crystallization unit carries outEvaporative crystallization obtains Na2SO4Crystal and Na2SO4Evaporate mother liquor, the Na2SO4Evaporation mother liquor continues evaporation and obtains mixed salt, describedMixed salt is discharged into dissolving tank the quenched tune amount of the nanofiltration conditioning tank that enters after dissolution, after enter back into the nano-filtration unit and divide salt；
(1.2) it as TDS < 100000mg/L of the nanofiltration concentrated water, needs through Na2SO4At depth upgrading unit depth concentrationNa is entered back into after reason2SO4Evaporative crystallization unit is handled；Further according to the COD content of the nanofiltration concentrated water, described in selectionThe specific processing method of nanofiltration concentrated water, specifically includes:
(1.2.1) as COD >=500mg/L of the nanofiltration concentrated water, the nanofiltration concentrated water need to be first through organic matter degradation unitDegradation treatment enters back into Na after the COD being effectively reduced in the nanofiltration concentrated water2SO4Depth upgrading unit depth concentration, mostEnter Na afterwards2SO4Evaporative crystallization unit is evaporated crystallization, it may be assumed that open the 9th shut-off valve, the 4th shut-off valve, the 6th shut-off valve and7th shut-off valve, the nanofiltration concentrated water sequentially enter organic matter degradation system and carry out organic matter degradation, Na2SO4Depth upgrading unitCarry out depth concentration, Na2SO4Evaporative crystallization unit is evaporated crystallization, obtains Na2SO4Crystal and Na2SO4Mother liquor is evaporated, it is describedNa2SO4Evaporation mother liquor continues evaporation and obtains mixed salt, and the mixed salt, which is discharged into dissolving tank, enters the nanofiltration conditioning tank tune after dissolutionMatter tune amount, after enter back into the nano-filtration unit and divide salt；
(1.2.2) as COD < 500mg/L of the nanofiltration concentrated water, the nanofiltration concentrated water need to be first through Na2SO4Depth concentration is singleFirst depth concentration, salt and organic concentration increase, after enter back into organic matter degradation unit degradation treatment, finally enterNa2SO4Evaporative crystallization unit is evaporated crystallization, it may be assumed that the tenth shut-off valve of opening, the 4th shut-off valve, the 5th shut-off valve and the 7th sectionOnly valve, the nanofiltration concentrated water sequentially enter Na2SO4Depth upgrading unit progress depth concentration, organic matter degradation system carry out organicObject degradation, Na2SO4Evaporative crystallization unit is evaporated crystallization, obtains Na2SO4Crystal and Na2SO4Evaporate mother liquor, the Na2SO4Evaporation mother liquor continues evaporation and obtains mixed salt, and the mixed salt, which is discharged into dissolving tank, enters the quenched tune of nanofiltration conditioning tank after dissolutionAmount, after enter back into the nano-filtration unit and divide salt；
(2) as c (Cl in the high saliferous industrial wastewater-): c (SO42-It, need to be according to the high saliferous Industry Waste when) < 1:2TDS content in water, selects specific processing method, specifically includes:
(2.1) as TDS >=100000mg/L in the high saliferous industrial wastewater, the second shut-off valve and the 5th section are openedOnly valve, the high saliferous industrial wastewater sequentially enter organic matter degradation unit and carry out organic matter degradation, Na2SO4Evaporative crystallization unitIt is evaporated crystallization, obtains Na2SO4Crystal and Na2SO4Evaporate mother liquor, the Na2SO4Evaporation mother liquor continues evaporation and obtains mixed salt,The mixed salt, which is discharged into dissolving tank after dissolution, enters nano-filtration unit progress nanofiltration point salt treatment, obtains nanofiltration and produces water and nanofiltrationConcentrated water；The nanofiltration production water sequentially enters NaCl depth upgrading unit progress depth concentration, NaCl evaporative crystallization unit is steamedHair crystallization, obtains NaCl crystal；The nanofiltration concentrated water returns to the nanofiltration conditioning tank, carries out circulation again and divides salt；
(2.2) it as TDS < 100000mg/L in the high saliferous industrial wastewater, needs through Na2SO4Depth upgrading unit is deepNa is entered back into after degree concentration2SO4Evaporative crystallization unit is handled；Further according in the high saliferous industrial wastewaterCOD content selects the specific processing method of the nanofiltration concentrated water, specifically includes:
(2.2.1) opens the second shut-off valve, the 4th shut-off valve as COD >=500mg/L in the high saliferous industrial wastewaterWith the 6th shut-off valve, the high saliferous industrial wastewater sequentially enters the organic matter degradation unit and carries out organic matter degradation, Na2SO4The concentration of depth upgrading unit depth, the Na2SO4Evaporative crystallization unit is evaporated crystallization, obtains Na2SO4Crystal and Na2SO4Evaporate mother liquor, the Na2SO4Evaporation mother liquor continues evaporation and obtains mixed salt, after the mixed salt enters dissolving tank dissolution, opening the 8thShut-off valve and the first shut-off valve, the dissolved mixed salt enter nano-filtration unit progress nanofiltration and divide salt treatment, obtain nanofiltrationProduce water and nanofiltration concentrated water；The nanofiltration produces water and sequentially enters NaCl depth upgrading unit progress depth concentration, NaCl evaporative crystallizationUnit is evaporated crystallization, obtains NaCl crystal；The nanofiltration concentrated water returns to the nanofiltration conditioning tank, carries out circulation point againSalt；
(2.2.2) opens third shut-off valve, the 4th shut-off valve as COD < 500mg/L in the high saliferous industrial wastewaterWith the 5th shut-off valve, the high saliferous industrial wastewater sequentially enters the Na2SO4Depth upgrading unit depth is concentrated, is described organicObject degradation unit carries out organic matter degradation, the Na2SO4Evaporative crystallization unit is evaporated crystallization, obtains Na2SO4Crystal andNa2SO4Evaporate mother liquor, the Na2SO4Evaporation mother liquor, which continues to evaporate, obtains mixed salt, after the mixed salt enters dissolving tank dissolution, beatsThe 8th shut-off valve and the first shut-off valve are opened, the dissolved mixed salt enters nano-filtration unit progress nanofiltration and divides salt treatment, obtainsWater and nanofiltration concentrated water are produced to nanofiltration；The nanofiltration produces water and sequentially enters NaCl depth upgrading unit progress depth concentration, NaCl steamingHair crystalline element is evaporated crystallization, obtains NaCl crystal；The nanofiltration concentrated water returns to the nanofiltration conditioning tank, carries out againCirculation divides salt.
Advantages of the present invention: the present invention it is a kind of improve crystallization purity salt and resource rate divide salt system design rationally, canThe high saliferous industrial wastewater of efficient process separate sources, heterogeneity, different impurities content.
The present invention is a kind of to improve crystallization purity salt and resource rate is divided to the salt method to be in " two fraction of nanofiltration+evaporative crystallizationOn the basis of salt ", by nanofiltration concentrated water through evaporative crystallization output Na2SO4Evaporation mother liquor later continues evaporative crystallization output mixed salt(main component is NaCl and Na2SO4), nano-filtration unit front end is flowed back into after then dissolving mixed salt and repeats to divide salt, to enhanceNano-filtration unit divides salt action.Compared with it will directly evaporate mother liquor reflux to nano-filtration unit front end, in the mixed salt that this method generatesThe impurity contents such as organic matter, nitrate anion it is low, impact will not be generated because of reflux and to nano-filtration unit, and cause the impurity to beAccumulation inside system and to dividing salt to bring adverse effect；Evaporation is continued through or compared with freezing and crystallizing divides salt with mother liquor will be evaporated,This method can be resistant to very big impact load, will not reduce a point salt effect because of the biggish fluctuating range of influent quality.It shouldMethod also makes full use of nanofiltration membrane to the efficient rejection effect of organic matter, right by being used cooperatively with organic matter degradation systemOrganic matter in nanofiltration concentrated water carries out concentration efficient process, significantly improves crystallization purity salt and crystal salt yield.
Organic matter degradation unit is placed on after nanofiltration divides salt by the present invention, greatly reduces treating capacity, save the cost；In nanofiltrationDivide after salt, most organic is trapped within nanofiltration concentrated water side, and since nanofiltration divides salt, dense discharge reduction causes organicObject is concentrated at double, therefore organic matter degradation is high-efficient in the present invention, and removal effect is good.
In the present invention, after nanofiltration divides salt for the first time, will according to chlorine ion concentration and sulfate ion concentration in nanofiltration concentrated water,Evaporation is divided salt to obtain the crystal salt of high-quality or evaporates the mixture of sodium chloride and sodium sulphate by selectivity, then by moltenSolution flows back into nanofiltration front end.The effect that nanofiltration divides salt is enhanced, ensure that a point salt effect, while greatly reducing evaporation and dividing saltDifficulty and energy consumption.
In the present invention, for the concentration ratio of chloride ion and sulfate ion in salt concentrate to be divided, selective designDivide concentration and evaporation after salt, or first concentration and evaporation to divide salt in nanofiltration for first nanofiltration, guarantees that nanofiltration divides salt in the case where most preferably dividing salt state, mentionHigh score salt efficiency and ability.
Detailed description of the invention:
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show belowThere is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only thisSome embodiments of invention for those of ordinary skill in the art without creative efforts, can be withIt obtains other drawings based on these drawings.
Fig. 1, which is that embodiment 1 is a kind of, improves crystallization purity salt and resource rate divides salt system schematic diagram.
In figure: nanofiltration conditioning tank 1, nano-filtration unit 2, NaCl depth upgrading unit 3, NaCl evaporative crystallization unit 4, organic matterDegradation unit 5, Na2SO4Depth upgrading unit 6, Na2SO4Evaporative crystallization unit 7, dissolving tank 8, the first shut-off valve 9, the second cut-offValve 10, third shut-off valve 11, the 4th shut-off valve 12, the 5th shut-off valve 13, the 6th shut-off valve 14, the 7th shut-off valve 15, the 8th sectionOnly valve 16, the 9th shut-off valve 17, the tenth shut-off valve 18.
Specific embodiment:
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, completeSite preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based onEmbodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every otherEmbodiment shall fall within the protection scope of the present invention.
Embodiment 1:
It is a kind of to improve crystallization purity salt and resource rate divides salt system comprising nanofiltration conditioning tank 1, nano-filtration unit 2,NaCl depth upgrading unit 3, NaCl evaporative crystallization unit 4, organic matter degradation unit 5, Na2SO4Depth upgrading unit 6, Na2SO4Evaporative crystallization unit 7 and dissolving tank 8；
Nanofiltration conditioning tank 1 respectively with nano-filtration unit 2, organic matter degradation unit 5, Na2SO4Depth upgrading unit 6 passes through pipelineConnection, connection nanofiltration conditioning tank 1 and nano-filtration unit 2 pipeline on be equipped with the first shut-off valve 9, connection nanofiltration conditioning tank 1 withThe pipeline of organic matter degradation unit 5 is equipped with the second shut-off valve 10, in connection nanofiltration conditioning tank 1 and Na2SO4Depth upgrading unit 6Pipeline be equipped with third shut-off valve 11；
Nano-filtration unit 2 is connect with NaCl depth upgrading unit 3 by pipeline, and NaCl depth upgrading unit 3 and NaCl evaporateCrystalline element 4 is connected by pipeline；
Organic matter degradation unit 5 respectively with Na2SO4Depth upgrading unit 6 and Na2SO4Evaporative crystallization unit 7 passes through pipelineConnection, in connection organic matter degradation unit 5 and Na2SO4The pipeline of depth upgrading unit 6 is equipped with the 4th shut-off valve 12, is being connected toOrganic matter degradation unit 5 and Na2SO4The pipeline of evaporative crystallization unit 7 is equipped with the 5th shut-off valve 13；Na2SO4Depth concentration is single6 and Na of member2SO4Evaporative crystallization unit 7 is connected by pipeline, in connection Na2SO4Depth upgrading unit 6 and Na2SO4Evaporative crystallizationPipeline between unit 7 is equipped with the 6th shut-off valve 14；Na2SO4The mixed salt outlet of evaporative crystallization unit 7 is connect with dissolving tank 8,Dissolving tank 8 is connect with nanofiltration conditioning tank 1 and nano-filtration unit 2 by pipeline respectively, in connecting dissolution slot 8 and nanofiltration conditioning tank 1Pipeline is equipped with the 7th shut-off valve 15, and the 8th shut-off valve 16 is equipped on connecting dissolution slot 8 and the pipeline of nano-filtration unit 2；
Nano-filtration unit 2 respectively with organic matter degradation unit 5, Na2SO4Depth upgrading unit 6 is connected by pipeline, is being connected toPipeline between nano-filtration unit 2 and organic matter degradation unit 5 is equipped with the 9th shut-off valve 17, in connection nano-filtration unit 2 and Na2SO4Pipeline between depth upgrading unit 6 is equipped with the tenth shut-off valve 18.
As a kind of specific embodiment, nano-filtration unit 2 uses the combining form of two-stage nanofiltration.
As a kind of specific embodiment, NaCl depth upgrading unit 3 and Na2SO4Depth upgrading unit 6 is all made of can be withIt is high-pressure flat plate film (DTRO).
As a kind of specific embodiment, organic matter degradation unit 5 is three-dimensional integrated using ozone, ultrasonic wave, ultraviolet lightThe combination of advanced oxidation unit.
As a kind of specific embodiment, NaCl evaporative crystallization unit 4 and Na2SO4Evaporative crystallization unit 7 is all made of evaporationCrystalline element 7.
Embodiment 2:
Certain coal-to-olefin item is handled using a kind of point salt system for improving crystallization purity salt and resource rate described in embodiment 1Purpose waste water,
Waste water water Q:10m3/ h, COD:60mg/L, TDS:15503mg/L, Cl-: 4695mg/L, SO42-: 5300mg/L, total hardness: 2101mg/L, silica: 35mg/L, turbidity: 4NTU.
After front end pretreatment and preliminary film concentration, ion exchange resin, into the high saliferous Industry Waste of nanofiltration conditioning tank 1Water water quality indicator are as follows: TDS=75011mg/L, Cl-=22990mg/L, SO42-=25020mg/L, total hardness 0.5mg/L,COD=315mg/L, pH 7.5, flow Q=2.0m3/h。
The first shut-off valve 9 is opened, high saliferous industrial wastewater enters nano-filtration unit 2 and carries out nanofiltration processing, obtains nanofiltration and produces waterWith nanofiltration concentrated water；
Wherein, nanofiltration produces water TDS=43015mg/L, total hardness 0mg/L, Cl-=26052mg/L, SO42-=82mg/L, COD=120mg/L, nanofiltration produce water flow Q=1.36m3/h；Nanofiltration concentrated water TDS=115011mg/L, total hardness 2.5mg/L,SO42-=66001mg/L, Cl-=12500mg/L, COD=685mg/L, nanofiltration concentrated water flow 0.64m3/h。
Nanofiltration production water sequentially enters the progress of NaCl depth upgrading unit 3 depth concentration, NaCl evaporative crystallization unit 4 is steamedHair crystallization produces to obtain NaCl crystal salt, and NaCl depth upgrading unit 3 uses DTRO system, and NaCl evaporative crystallization unit 4 uses MVREvaporative crystallization unit, the NaCl crystallization purity salt produced is 99.7%, meets " Nacl " (GB/T 5462-2015) " purification workIndustry salt level-one " standard.
The 9th shut-off valve 17 and the 5th shut-off valve 13 are opened, nanofiltration concentrated water enters organic matter degradation unit 5 and carries out organic matterDegradation, the organic matter degradation unit three-dimensional integrated using ozone, ultrasonic wave, ultraviolet light of organic matter degradation unit 5；It is discharged TDS=115011mg/L, COD=101mg/L then enter Na2SO4Evaporative crystallization unit 7 is evaporated crystallization, at a temperature of 105 DEG CObtain Na2SO4Crystal and Na2SO4Evaporate mother liquor, Na2SO4Evaporative crystallization system is crystallized using triple effect evaporation；The sodium sulphate knot producedBrilliant purity salt is 98.8%, meets " industrial anhydrous sodium sulfate " (GB/T 6009-2014) " II class Grade A " standard；
Na2SO4Evaporation mother liquor continues evaporation to obtain main component to be Na2SO4With the mixed salt of NaCl, mixed salt is discharged into dissolving tank 8It is interior to enter the quenched tune amount of nanofiltration conditioning tank 1 after the dissolution of system total yield water, it is again introduced into this system circulation and divides salt；
By 72 hours continuous operations, 720 tons of water are handled, obtains 5.3 tons of NaCl crystal salt, Na2SO4Crystal salt 4.5Ton, crystal salt relative productivity (crystal salt relative productivity=NaCl crystal salt and Na2SO4Crystal salt product volume/salinity of always intaking) be90.7%.
Embodiment 3:
Certain coal-to-olefin item is handled using a kind of point salt system for improving crystallization purity salt and resource rate described in embodiment 1Purpose waste water,
Waste water water Q:10m3/ h, COD:65mg/L, TDS:10180mg/L, Cl:3065mg/L, SO42-: 3802mg/L, total hardness: 2489mg/L, silica: 47mg/L, turbidity: 3NTU, through front end pretreatment and preliminary film concentration, ion exchangeAfter resin, into the high saliferous industrial wastewater water quality indicator of nanofiltration conditioning tank 1 are as follows: TDS=55220mg/L, Cl-=16621mg/L, SO42-=18519mg/L, total hardness 0.5mg/L, COD=335mg/L, pH=7.5, flow Q=1.2m3/h。
The first shut-off valve 9 is opened, high saliferous industrial wastewater enters nano-filtration unit 2 and carries out nanofiltration processing, obtains nanofiltration and produces waterWith nanofiltration concentrated water；
Wherein, nanofiltration produces water TDS=30560mg/L, total hardness 0mg/L, Cl-=19775mg/L, SO42-=52mg/L, COD=125mg/L, nanofiltration produce water flow Q=0.815m3/h；Nanofiltration concentrated water TDS=80700mg/L, total hardness 2.55mg/L, SO42-=54022.9mg/L, Cl-=9945mg/L, COD=795mg/L, nanofiltration concentrated water flow 0.385m3/h。
Nanofiltration production water sequentially enters the progress of NaCl depth upgrading unit 3 depth concentration, NaCl evaporative crystallization unit 4 is steamedHair crystallization produces to obtain NaCl crystal salt, and NaCl depth upgrading unit 3 uses DTRO system, and NaCl evaporative crystallization unit 4 uses MVREvaporative crystallization unit, the NaCl crystallization purity salt produced is 99.7%, meets " Nacl " (GB/T 5462-2015) " purification workIndustry salt level-one " standard.
Meanwhile it is dense to open the 9th shut-off valve 17, the 4th shut-off valve 12, the 6th shut-off valve 14 and the 7th shut-off valve 15, nanofiltrationWater enters organic matter degradation unit 5 and carries out organic matter degradation, and organic matter degradation unit 5 is three-dimensional using ozone, ultrasonic wave, ultraviolet lightThe organic matter degradation unit of one；It is discharged TDS=80500mg/L, COD=105mg/L, then enters Na2SO4Depth concentration is singleMember 6 carries out depth concentration, Na2SO4Depth upgrading unit 6 uses DTRO system, is discharged TDS=181350mg/L, COD=225mg/L finally enters Na2SO4Evaporative crystallization unit 7 is evaporated crystallization, obtains Na at a temperature of 105 DEG C2SO4Crystal andNa2SO4Evaporate mother liquor, Na2SO4Evaporative crystallization system is crystallized using triple effect evaporation；The sulfate crystal purity salt produced is98.7%, meet " industrial anhydrous sodium sulfate " (GB/T 6009-2014) " II class Grade A " standard；
Na2SO4Evaporation mother liquor continues evaporation to obtain main component to be Na2SO4With the mixed salt of NaCl, mixed salt is discharged into dissolving tank 8It is interior to enter the quenched tune amount of nanofiltration conditioning tank 1 after the dissolution of system total yield water, it is again introduced into this system circulation and divides salt；
By 72 hours continuous operations, 720 tons of water are handled, obtains 3.1 tons of NaCl crystal salt, Na2SO4Crystal salt 3.4Ton, crystal salt relative productivity (crystal salt relative productivity=NaCl crystal salt and Na2SO4Crystal salt product volume/salinity of always intaking) be89%.
Embodiment 4:
Certain coal-to-olefin item is handled using a kind of point salt system for improving crystallization purity salt and resource rate described in embodiment 1Purpose waste water,
Waste water water Q:20m3/ h, COD:35mg/L, TDS:101850mg/L, Cl-: 3055mg/L, SO42-: 3800mg/L, total hardness: 2545mg/L, silica: 42mg/L, turbidity: 2.5NTU.It is handed over through front end pretreatment and preliminary film concentration, ionAfter changing resin, into the high saliferous industrial wastewater water quality indicator of nanofiltration conditioning tank 1 are as follows: TDS=54980mg/L, Cl-=16211mg/L, SO42-=18513mg/L, total hardness 0.5mg/L, COD=179mg/L, pH=7.5, flow Q=2.4m3/h。
Open the first shut-off valve 9, high saliferous industrial wastewater enters nano-filtration unit and carries out nanofiltration processing, obtain nanofiltration produce water andNanofiltration concentrated water；
Wherein, nanofiltration produces water TDS=30490mg/L, total hardness 0mg/L, Cl-=19735mg/L, SO42-=51.5mg/L, COD=63mg/L, nanofiltration produce water flow Q=1.63m3/h；Nanofiltration concentrated water TDS=80505mg/L, total hardness2.5mg/L, SO42-=54012.5mg/L, Cl-=8751mg/L, COD=441mg/L, nanofiltration concentrated water flow 0.77m3/h。
Nanofiltration production water sequentially enters the progress of NaCl depth upgrading unit 3 depth concentration, NaCl evaporative crystallization unit 4 is steamedHair crystallization produces to obtain NaCl crystal salt, and NaCl depth upgrading unit 3 uses DTRO system, and NaCl evaporative crystallization unit 4 uses MVREvaporative crystallization unit, the NaCl crystallization purity salt produced is 99.8%, meets " Nacl " (GB/T 5462-2015) " purification workIndustry salt level-one " standard.
The tenth shut-off valve 18, the 4th shut-off valve 12, the 5th shut-off valve 13 and the 7th shut-off valve 15 are opened, nanofiltration concentrated water entersNa2SO4Depth upgrading unit 6 carries out depth concentration, Na2SO4Depth upgrading unit 6 uses DTRO system, is discharged TDS=181350mg/L, COD=789mg/L then enter organic matter degradation unit 5 and carry out organic matter degradation, organic matter degradation unit 5Using the three-dimensional integrated organic matter degradation unit of ozone, ultrasonic wave, ultraviolet light；It is discharged TDS=181350mg/L, COD=103mg/L finally enters Na2SO4Evaporative crystallization unit 7 is evaporated crystallization, obtains Na at a temperature of 105 DEG C2SO4Crystal andNa2SO4Evaporate mother liquor, Na2SO4Evaporative crystallization system is crystallized using triple effect evaporation；The sulfate crystal purity salt produced is98.9%, meet " industrial anhydrous sodium sulfate " (GB/T 6009-2014) " II class Grade A " standard；
Na2SO4Evaporation mother liquor continues evaporation to obtain main component to be Na2SO4With the mixed salt of NaCl, mixed salt is discharged into dissolving tank 8It is interior to enter the quenched tune amount of nanofiltration conditioning tank 1 after the dissolution of system total yield water, it is again introduced into this system circulation and divides salt；
By 36 hours continuous operations, 720 tons of water are handled, obtains 3.1 tons of NaCl crystal salt, Na2SO4Crystal salt 3.5Ton, crystal salt relative productivity (crystal salt relative productivity=NaCl crystal salt and Na2SO4Crystal salt product volume/salinity of always intaking) be90.3%.
Embodiment 5:
Certain coal to olefin project is handled using a kind of point salt system for improving crystallization purity salt and resource rate of embodiment 1Waste water,
Waste water water Q:6m3/ h, COD:605mg/L, TDS:110150mg/L, Cl-: 18055mg/L, SO42-:52005mg/L, total hardness: 3009mg/L, silica: 49mg/L, turbidity: 3.5NTU.
After front end pretreatment and preliminary film concentration, ion exchange resin, the height into nanofiltration conditioning tank 11 contains salt industrialWaste water quality index are as follows: TDS=103220mg/L, Cl-=18031mg/L, SO42-=52009mg/L, total hardness 0.5mg/L, COD=585mg/L, pH=7.5, flow Q=6m3/h。
The second shut-off valve 10 and the 5th shut-off valve 13 are opened, high saliferous industrial wastewater enters the progress of organic matter degradation unit 5Organic matter degradation, the organic matter degradation unit three-dimensional integrated using ozone, ultrasonic wave, ultraviolet light of organic matter degradation unit 5, water outletTDS=103220mg/L, Cl-=18031mg/L, SO42-=52009mg/L, total hardness 0.5mg/L, COD=85mg/L, andEnter Na afterwards2SO4Evaporative crystallization unit 7 is evaporated crystallization, obtains Na at a temperature of 105 DEG C2SO4Crystal and Na2SO4Evaporation is femaleLiquid；Na2SO4Evaporation mother liquor continues evaporation and obtains mixed salt, and mixed salt enters nano-filtration unit 2 after the dissolution of system total yield water and carries out nanofiltrationDivide salt, solution TDS=75005mg/L, Cl after mixed salt dissolution-=34031mg/L, SO42-=14009mg/L, pH 7.3, flowFor Q=3.2m3/h。
The nanofiltration obtained after nanofiltration divides salt produces water and nanofiltration concentrated water, and nanofiltration produces water TDS=61560mg/L, and total hardness is0mg/L, Cl-=37725mg/L, SO42-=95mg/L, COD=25mg/L, nanofiltration produce water flow 2.4m3/h.Nanofiltration concentrated water TDS=110701mg/L, total hardness 2.5mg/L, SO42-=56305mg/L, Cl-=16545mg/L, COD=415mg/L, nanofiltration are denseWater flow 0.8m3/ h, nanofiltration concentrated water return to nanofiltration conditioning tank 1 and carry out quenched tune amount, and then circulation divides salt；Nanofiltration produce water successively intoEnter NaCl depth upgrading unit 3 and carry out depth concentration, NaCl evaporative crystallization unit 4 to be evaporated crystallization, produces to obtain NaCl crystal salt,NaCl depth upgrading unit 3 uses DTRO system, and NaCl evaporative crystallization unit 4 uses MVR evaporative crystallization unit, the NaCl producedCrystallizing purity salt is 99.3%, meets " Nacl " (GB/T 5462-2015) " refining industrial salt level-one " standard；The sulphur producedSour sodium crystallization purity salt is 99.1%, meets " industrial anhydrous sodium sulfate " (GB/T 6009-2014) " II class Grade A " standard.
By 72 hours continuous operations, 432 tons of water are handled, obtains 9.8 tons of NaCl crystal salt, Na2SO4Crystal salt 30.2Ton, crystal salt relative productivity (crystal salt relative productivity=NaCl crystal salt and Na2SO4Crystal salt product volume/salinity of always intaking) be89.4%.
Embodiment 6:
Certain coal to olefin project is handled using a kind of point salt system for improving crystallization purity salt and resource rate of embodiment 1Waste water,
Waste water water Q:10m3/ h, COD:605mg/L, TDS:31750mg/L, Cl-: 6058mg/L, SO42-:15802mg/L, total hardness: 608mg/L, silica: 30mg/L, turbidity: 3.5NTU.
After front end pretreatment and preliminary film concentration, ion exchange resin, the height into nanofiltration conditioning tank 11 contains salt industrialWaste water quality index are as follows: TDS:30850mg/L, Cl-: 6163mg/L, SO42-: 15407mg/L, total hardness 0.5mg/L, COD=575mg/L, pH 7.1, flow Q=10m3/h。
The second shut-off valve 10, the 4th shut-off valve 12 and the 6th shut-off valve 14 are opened, high saliferous industrial wastewater has initially enteredMachine object unit 5 of degrading carries out organic matter degradation, organic matter degradation unit 5 using ozone, ultrasonic wave, ultraviolet light is three-dimensional integrated hasMachine object degradation unit, is discharged TDS=30850mg/L, COD=85mg/L, then enters Na2SO4Depth upgrading unit 6 carries out depthDegree concentration, Na2SO4Depth upgrading unit 6 uses DTRO system, is discharged TDS=165345mg/L, COD=415mg/L, most laggardEnter Na2SO4Evaporative crystallization unit 7 is evaporated crystallization, obtains Na at a temperature of 105 DEG C2SO4Crystal and Na2SO4Mother liquor is evaporated,Na2SO4Evaporative crystallization system is crystallized using triple effect evaporation；The sulfate crystal purity salt produced is 98.9%, is met " industrial anhydrousSodium sulphate " (GB/T 6009-2014) " II class Grade A " standard；
Na2SO4Evaporation mother liquor continues evaporation and obtains mixed salt, Na2SO4Evaporation mother liquor continues evaporation and obtains main component and beNa2SO4With the mixed salt of NaCl, mixed salt, which is discharged into dissolving tank 8, divides salt into the progress nanofiltration of nano-filtration unit 2 through the dissolution of system total yield water,Solution TDS=45005mg/L, Cl after mixed salt dissolution-=20842mg/L, SO42-=8109mg/L, pH=7.3, flow Q=2.6m3/h。
The nanofiltration obtained after nanofiltration divides salt produces water and nanofiltration concentrated water, and nanofiltration produces water TDS=33960mg/L, and total hardness is0mg/L, Cl-=21718mg/L, SO42-=85mg/L, COD=165mg/L, nanofiltration produce water flow Q=2.1m3/h.Nanofiltration concentrated waterTDS=95705mg/L, total hardness 2.5mg/L, SO42-=46605mg/L, Cl-=17045mg/L, COD=615mg/L, nanofiltrationConcentrated water flow Q=0.45m3/ h, nanofiltration concentrated water return to nanofiltration conditioning tank 1 and carry out quenched tune amount, and then circulation divides salt；Nanofiltration produces waterIt sequentially enters NaCl depth upgrading unit 3 and carries out depth concentration, NaCl evaporative crystallization unit 4 and be evaporated crystallization, produce to obtain NaClCrystal salt, NaCl depth upgrading unit 3 use DTRO system, and NaCl evaporative crystallization unit 4 uses MVR evaporative crystallization unit, produceThe NaCl crystallization purity salt obtained is 99.7%, meets " Nacl " (GB/T 5462-2015) " refining industrial salt level-one " standard.
By 72 hours continuous operations, 720 tons of water are handled, obtains 6.1 tons of NaCl crystal salt, Na2SO4Crystal salt 14.4Ton, crystal salt relative productivity (crystal salt relative productivity=NaCl crystal salt and Na2SO4Crystal salt product volume/salinity of always intaking) be92.0%.
Embodiment 7:
Certain coal to olefin project is handled using a kind of point salt system for improving crystallization purity salt and resource rate of embodiment 1Waste water,
Waste water water Q:10m3/ h, COD:125mg/L, TDS:31305mg/L, Cl-: 6102mg/L, SO42-:14975mg/L, total hardness: 605mg/L, silica: 33mg/L, turbidity: 3.5NTU.
After front end pretreatment and preliminary film concentration, ion exchange resin, the height into nanofiltration conditioning tank 11 contains salt industrialWaste water quality index are as follows: TDS:31215mg/L, Cl-: 6165mg/L, SO42-: 14807mg/L, total hardness 0.5mg/L, COD=125mg/L, pH 7.4, flow Q=10m3/h。
Third shut-off valve 11, the 4th shut-off valve 12 and the 5th shut-off valve 13, high saliferous industrial wastewater is opened to initially enterNa2SO4Depth upgrading unit 6 carries out depth concentration, Na2SO4Depth upgrading unit 6 uses DTRO system, is discharged TDS=175035mg/L, COD=635mg/L；Then enter organic matter degradation unit 5 and carries out organic matter degradation, organic matter degradation unit 5Using the three-dimensional integrated organic matter degradation unit of ozone, ultrasonic wave, ultraviolet light, it is discharged TDS=175035mg/L, COD=89mg/L；Finally enter Na2SO4Evaporative crystallization unit 7 is evaporated crystallization, obtains Na at a temperature of 105 DEG C2SO4Crystal and Na2SO4It steamsSend out mother liquor, Na2SO4Evaporative crystallization system is crystallized using triple effect evaporation；The sulfate crystal purity salt produced is 98.7%, meets " workIndustry anhydrous sodium sulfate " (GB/T 6009-2014) " II class Grade A " standard；
Na2SO4Evaporation mother liquor continues evaporation and obtains mixed salt, Na2SO4Evaporation mother liquor continues evaporation and obtains main component and beNa2SO4With the mixed salt of NaCl, mixed salt, which is discharged into dissolving tank 8, divides salt into the progress nanofiltration of nano-filtration unit 2 through the dissolution of system total yield water,Solution TDS=46105mg/L, Cl after mixed salt dissolution-=21335mg/L, SO42-=8205mg/L, pH 7.2, flow Q=2.6m3/h。
The nanofiltration obtained after nanofiltration divides salt produces water and nanofiltration concentrated water, and nanofiltration produces water TDS=34135mg/L, and total hardness is0mg/L, Cl-=21833mg/L, SO42-=87mg/L, COD=45mg/L, nanofiltration produce water flow Q=2.1m3/h；Nanofiltration concentrated waterTDS=93908mg/L, total hardness 2.5mg/L, SO42-=46816mg/L, Cl-=17352mg/L, COD=315mg/L, nanofiltrationConcentrated water flow Q=0.45m3/h；Nanofiltration concentrated water returns to nanofiltration conditioning tank 1 and carries out quenched tune amount, and then circulation divides salt；Nanofiltration produces waterIt sequentially enters NaCl depth upgrading unit 3 and carries out depth concentration, NaCl evaporative crystallization unit 4 and be evaporated crystallization, produce to obtain NaClCrystal salt, NaCl depth upgrading unit 3 use DTRO system, and NaCl evaporative crystallization unit 4 uses MVR evaporative crystallization unit, produceThe NaCl crystallization purity salt obtained is 99.7%, meets " Nacl " (GB/T 5462-2015) " refining industrial salt level-one " standard.
By 72 hours continuous operations, 720 tons of water are handled, obtains 6.1 tons of NaCl crystal salt, Na2SO4Crystal salt 14.2Ton, crystal salt relative productivity (crystal salt relative productivity=NaCl crystal salt and Na2SO4Crystal salt product volume/salinity of always intaking) be93.4%.
The present invention is a kind of to improve crystallization purity salt and resource rate is divided to the salt method to be in " two fraction of nanofiltration+evaporative crystallizationOn the basis of salt ", by nanofiltration concentrated water through evaporative crystallization output Na2SO4Evaporation mother liquor later continues evaporative crystallization output mixed salt(main component is NaCl and Na2SO4), nano-filtration unit front end is flowed back into after then dissolving mixed salt and repeats to divide salt, to enhanceNano-filtration unit divides salt action.Compared with it will directly evaporate mother liquor reflux to nano-filtration unit front end, in the mixed salt that this method generatesThe impurity contents such as organic matter, nitrate anion it is low, impact will not be generated because of reflux and to nano-filtration unit, and cause the impurity to beAccumulation inside system and to dividing salt to bring adverse effect；Evaporation is continued through or compared with freezing and crystallizing divides salt with mother liquor will be evaporated,This method can be resistant to very big impact load, will not reduce a point salt effect because of the biggish fluctuating range of influent quality.It shouldMethod also makes full use of nanofiltration membrane to the efficient rejection effect of organic matter, right by being used cooperatively with organic matter degradation systemOrganic matter in nanofiltration concentrated water carries out concentration efficient process, it is found that crystallization purity salt produced by the invention and production from embodimentRate is higher.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all in essence of the inventionWithin mind and principle, any modification, equivalent replacement, improvement and so on be should all be included in the protection scope of the present invention.