CN101948211A - Method for treating vanadium oxide production wastewater - Google Patents
Method for treating vanadium oxide production wastewater Download PDFInfo
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- CN101948211A CN101948211A CN 201010287443 CN201010287443A CN101948211A CN 101948211 A CN101948211 A CN 101948211A CN 201010287443 CN201010287443 CN 201010287443 CN 201010287443 A CN201010287443 A CN 201010287443A CN 101948211 A CN101948211 A CN 101948211A
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- dense medium
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- vanadium oxide
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Abstract
本发明涉及一种处理氧化钒生产废水的方法。该方法包括：对氧化钒生产废水进行蒸发和浓缩，以获得主要成分是硫酸钠和硫酸铵的结晶物；将所述结晶物加入到重介质中并不断搅拌，使得所述结晶物在重介质中分层；将重介质中形成分层的上下两层物质从重介质中去除。通过本发明的方法，可以有效地使获得的结晶物中的主要成分硫酸钠和硫酸铵分离，从而可以对它们进行再利用，避免了其中的离子最终以有害气体的形式排放到外部环境中而造成污染。The invention relates to a method for treating waste water produced by vanadium oxide. The method comprises: evaporating and concentrating the vanadium oxide production waste water to obtain crystals whose main components are sodium sulfate and ammonium sulfate; Middle stratification; remove the upper and lower layers of substances that form stratification in the dense medium from the dense medium. By the method of the present invention, the main component sodium sulfate and ammonium sulfate in the obtained crystals can be effectively separated, so that they can be reused, avoiding that the ions therein are finally discharged into the external environment in the form of harmful gases. create pollution.
Description
Technical field
The present invention relates to a kind of method of handling the vanadium oxide factory effluent, more particularly, relate to a kind of handle vanadium oxide factory effluent evaporation and concentrate after the method for the crystallisate that obtains.
Background technology
At present, the raw materials for production of vanadium oxide mainly are vanadium titano-magnetites, also are the important source material sources that vanadium oxide is produced and spent catalyst, oil burn slag and contain scherbinaite coal etc.For raw materials for production are situations of vanadium titano-magnetite, except that rare employing calcification baking-acidleach-hydrolysis precipitation technology (abbreviation lime method), most of production plants adopt sodium roasting-water logging-ammonium salt precipitation technology (being called for short the sodium salt method), the vanadium quality product height of this explained hereafter is produced stable.For raw materials for production are situations that spent catalyst, oil burn slag and contain scherbinaite coal etc., and manufacturer also adopts ammonium salt precipitation method usually in order to obtain high-quality vanadium product, has therefore unavoidably produced NH
4 +Content reaches the above high salinity acid waste water of 4000mg/L.
Consider environmental protection problem, need handle factory effluent.The common methods that is used for removing waste water ammonium ion etc. has biological treatment and physico-chemical processes.The example of biological treatment can be that publication number is the application for a patent for invention of CN1609016.Because inorganic high ammonia nitrogen vanadium oxide factory effluent contains very high salinity, so adopt physico-chemical processes usually.Physico-chemical processes mainly comprises air stripping and steam stripped method, break point chlorination method, ion exchange method, chemical precipitation method and crystallization process etc.
Air stripping and steam stripped method are to utilize the difference that exists between the actual concentrations of volatile matter such as ammonia contained in the waste water, nitrogen and the equilibrium concentration, under alkaline condition with air stripping or use steam stripped, volatile matter such as ammonia nitrogen in the waste water are constantly transferred in the gas phase by liquid phase, thereby reached the purpose of from waste water, removing ammonia nitrogen.This technology is simple, and efficient height (clearance can reach more than 90%) is used more in the high ammonia-nitrogen wastewater ammonia nitrogen removal technology of chemical industry.Yet when envrionment temperature was low, stripping tower can't move, and the easy fouling of inner-tower filling material, influenced the operation of deamination effect and equipment when serious; Though the steam stripped tower is filled out the influence that has overcome envrionment temperature, the running cost height, the filler fouling is even more serious.Generally speaking, have only when the ammonia nitrogen concentration in the water and when 10000mg/L is above, just consider to use stripping process, otherwise economy is relatively poor.
The break point chlorination method is that the chlorine of q.s or hypochlorite are put in the waste water, and when input amount reaches certain when a bit, cl content contained in the waste water is lower, and ammonia-nitrogen content trends towards zero; As chlorine feeding amount or ClO
-Free chlorine content when add-on surpasses at described in the water rises, this point often is called break, and under this state, the ammonia nitrogen in the waste water often is oxidized to nitrogen and removes, usually the add-on of chlorine is 7～12: 1 with the ratio of ammonia-nitrogen content, can make to handle in the water ammonia nitrogen concentration later less than 0.1mg/l.This method is fit to the ammonia nitrogen waste water of different concns, but handles high ammonia nitrogen running cost height, also has security risk simultaneously.Therefore, application is less in the ammonia nitrogen waste water treatment project.
Ion exchange method is selected oblique euthalite resin in return for use, with ammonium ion in the water and the exchange of the sodium ion on the resin, thereby reaches the purpose of removing ammonia.The sodium chloride solution regeneration of the normal employing 2% of zeolite, regenerated liquid is handled back recirculation use through deamination.In general, the ion-exchange ammonia elimination process is applicable to the waste water deamination of ammonia nitrogen concentration at 10～100mg/l, and is not suitable for the higher waste water of ammonia nitrogen concentration is handled.
The chemical precipitation denitrogenation is a kind of new technology of rising the sixties in 20th century, and this method can be handled the ammonia nitrogen waste water of various concentration, is particularly suitable for the processing of high-concentration ammonia nitrogenous wastewater.When the ammonia nitrogen waste water of some high density, owing to contain in the time of should not adopting biochemical treatment to the deleterious material of microorganism in a large number, can handle with chemical precipitation, chemical precipitation method has the nitric efficiency more than 90% usually, and technology is also simpler.Just being applied to ammonia nitrogen waste water from the sixties in last century chemical precipitation method handles.People such as Japanese KenichiEbats added Mg in ammonia nitrogen waste water in 1977
2+And PO
4 3-, make it and NH
4 +Reaction generates indissoluble double salt MgNH
4PO
46H
2O (MAP) is by the NH4 in the MAP removal waste water
+But owing to make dosage excessive, cost is higher.
Crystallization process is to obtain the purpose that crystallisate reaches the removal ammonium ion by the vanadium oxide factory effluent being carried out evaporation concentration, and the main component of this crystallisate is sodium sulfate and ammonium sulfate.For the sodium sulfate in the waste water is used, a certain amount of coal can be added in the crystallisate that obtains as thermal source and reductive agent, be used to produce sodium sulphite.Because contain a large amount of ammonium sulfate and water in the crystallisate, ammonium sulfate at high temperature decomposes, and does not discharge if flue gas is treated, wherein the SO of Xing Chenging
2Can cause serious environmental to pollute Deng obnoxious flavour, and also can't recycle ammonium sulfate.
Summary of the invention
The objective of the invention is to propose a kind ofly can solve the above-mentioned method of utilizing crystallization process to handle one or more problems that exist in the vanadium oxide factory effluent technology basically, promptly, a kind of method of utilizing the dense medium isolation technique to handle the crystallisate that obtains after the vanadium oxide factory effluent evaporation concentration is provided, thereby can avoid ion in the vanadium oxide waste water to discharge effectively and cause environmental pollution, can recycle isolating ion from waste water in addition with the form of obnoxious flavour.
The method of treatment in accordance with the present invention vanadium oxide factory effluent may further comprise the steps: the vanadium oxide factory effluent is evaporated and concentrates, and is the crystallisate of sodium sulfate and ammonium sulfate to obtain main component; Described crystallisate is joined in the dense medium and constantly stir, make the layering in dense medium of described crystallisate; Remove from dense medium forming stratified two-layer material up and down in the dense medium.
The temperature of dense medium is 60 ℃ to 110 ℃.
The density of dense medium is between the density of described sodium sulfate and described ammonium sulfate.The density of dense medium is at 1.8g/cm
3-2.6g/cm
3Scope in.
Dense medium can exist with the form of solution or suspension.
Dense medium can be the suspension that medium solid forms.
Described medium solid can be ferrosilicon, magnetite, lead ore, ilmenite, pyrite or magnetic bead etc.
The granularity of described medium solid can be in 100 order to 400 purpose scopes.
The method of treatment in accordance with the present invention vanadium oxide factory effluent also can comprise by the medium solid in magnetic separation, electric separation or the gravity treatment separation dense medium, to recycle the step of this medium solid.
The method of treatment in accordance with the present invention vanadium oxide factory effluent also can comprise by the two-layer material that will remove water-soluble respectively make the aqueous solution and the described aqueous solution filtered obtain medium solid, to recycle the step of this medium solid.
Dense medium can be an organic solution.
Embodiment
Principle of the present invention is to utilize gravity to come compounding substances is carried out sorting.The gravitational segregation process is all carried out in certain medium.When the density of the separating medium that uses greater than 1g/cm
3The time, this medium is called dense medium.Material is subjected to gravity and buoyancy function in dense medium, will float in medium less than the material of the density of dense medium, and will sink in medium greater than the material of the density of dense medium.Usually, utilize the principle of dense medium separation material and technology mainly to be used in ore dressing and the coal preparation technique, and the present inventor creatively is applied in the dense medium isolation technique in the middle of the processing of vanadium oxide factory effluent.Therefore, the term among the present invention " dense medium " has identical implication with term in the application such as ore dressing and coal separation.
Dense medium has four types, that is, organic solution, salt, wind sand medium (fill in the sand grains with air and form suspensoid), solids soluble in water mix the suspension of forming with water.Preceding two kinds is stable, and then two kinds is unstable medium (or artificial stability medium).In an embodiment according to the present invention, show the material of finishing in the crystallisate with the dense medium of first kind and the 4th type to be separated and carry out separating process, but the present invention is not limited thereto, also can adopt the dense medium of second kind or the third type to carry out sorting.
The method according to this invention can be to producing V
2O
5, VO
2, V
2O
3Or VO a kind of or their waste water that mixture produced are handled.
In the method for the invention, at first pending vanadium oxide factory effluent being evaporated and concentrate, is the crystallisate of sodium sulfate and ammonium sulfate to obtain main component.
The dense medium of prep solution form or form of suspension.Can with common such as medium solids such as ferrosilicon, magnetite, lead ore, ilmenite, pyrite or magnetic bead add in the entry and the suspension that obtains as dense medium, also can as required homemade solia particle be added in the entry and the suspension that obtains as dense medium.Usually, the granularity of medium solid is thick more, and its sedimentation speed is fast more and viscosity is low more, and the medium solid granularity is thin more, its sedimentation speed is slow more and viscosity is high more, if the therefore excessive then suspension of the granularity of medium solid stable bad, if the undersized of medium solid then the mobile property of suspension is poor.So preferred, the granularity of medium solid is between 100 order to 400 orders.In addition, also can adopt salts solution or organic solution as dense medium, as long as can reach separating effect.The example of common salts solution comprises calcium chloride water, solder(ing)acid etc.The example of common organic solution comprises ethylene dibromide, methenyl bromide, tetrabromoethane etc.
Then, the crystallisate that obtains is added in the dense medium.Form double salt Na as the sodium sulfate of the main component of crystallisate and ammonium sulfate easily being lower than under 60 ℃ the temperature
2SO
4(NH
4)
2SO
44H
2O, and when the temperature of dense medium was too high, moisture in the dense medium system or organism evaporation were too fast, the smaller volume of dense medium system and density are changed, thereby cause the loss of dense medium.In addition, the too high liquid boiling that may make in the dense medium system of temperature is unfavorable for separating equally, so the temperature of dense medium can be controlled at 60 ℃ to 150 ℃ scope, preferably is controlled in 60 ℃ to 110 ℃ the scope.Can dense medium be remained on desired temperatures by internal heating or external heating mode.This temperature can record by industrial thermometer.
Need continuous stirring after in dense medium, adding crystallisate, can adopt the device of stirring rake and so on that mixed system is stirred.Stirring velocity in theory without limits, as long as can make two kinds of materials to be separated in the dense medium system, form layering.In other words, the situation difference of actually operating can make required stirring velocity difference.Make two kinds of materials to be separated form layering in the dense medium system, the density that must make dense medium is between the density of two kinds of materials to be separated.Under the ideal condition, the density of sodium sulfate pure substance is 2.6g/cm
3, the density of ammonium sulfate pure substance is 1.8g/cm
3, therefore, can select density at 1.8g/cm
3-2.6g/cm
3Dense medium in the scope realizes that material to be separated forms layering in dense medium.
In the step that in dense medium, adds crystallisate, the add-on of dense medium and crystallisate is had no particular limits, that is to say that the ratio to the two has no particular limits.In the initial stage, can add a spot of crystallisate earlier and constantly stir the observation separating effect.Usually, because the amount of the crystallisate of initial stage adding is fewer, so often just can observe separating effect after the short time, along with constantly adding crystallisate, the time that can observe separating effect may be long more.Therefore, as long as the dense medium system satisfies appropriate density and temperature requirement, the crystallisate that is added all there is separating effect, and separating effect also can be subjected to the influence of factors such as the viscosity of dense medium and stability, and the add-on of the unit time that this influence can be by the crystallization control thing and the stirring velocity of whipping appts are eliminated.
Material to be separated forms layering in dense medium after, the upper strata material and the lower floor's material that separate are removed.For example, can adopt the device such as scraper plate that the ammonium sulfate on upper strata is scraped, use the device such as mud discharging device that the sodium sulfate of lower floor is discharged, but the method and apparatus of removing upper strata material and lower floor's material be not limited to this.Because crystallisation process is subjected to influence of various factors, so the purity of upper strata material and lower floor's material may be not high, and owing to the part of this two-layer material that has separated has been blended in together again employed device in the levels material removal process, so can obtain more purified levels material by the mode of stage trapping.
In addition, be used as under the situation of dense medium, consider the cost of medium solid, medium solid can be separated from the dense medium system, with recycle at suspension with medium solid.Can adopt magnetic separation, electric separation or gravity treatment to separate medium solid in the dense medium, also can by the two-layer material that will remove water-soluble respectively make the aqueous solution and the described aqueous solution filtered obtain medium solid.
Embodiment 1
The vanadium oxide factory effluent is evaporated and concentrate,, use band filter that underflow is filtered and obtain solid matter to obtain to contain the underflow of crystallisate.Although present embodiment has used band filter, and filter is not limited thereto, and can also use filters such as plate-and-frame filter press.The atomizing ferrosilicon powder that 300 purposes are contained 18%Si approximately adds the dense medium that obtains form of suspension in the entry, and dense medium is remained under 70 ℃ the heat-retaining condition, makes the density of heavy-media suspension be about 2.2g/cm
3, this density records by the glass ball float specific gravity hydrometer.The solid matter that filtration is obtained joins in the dense medium for preparing and constantly stirring, and after demixing phenomenon was stable, topper mainly was an ammonium sulfate, if the owner of lower floor sodium sulfate.
Embodiment 2
The vanadium oxide factory effluent is evaporated and concentrating, is the crystallisate of sodium sulfate and ammonium sulfate to obtain main component.With ethylene dibromide solution (density 2.18g/cm
3) be heated to 70 ℃ and keep this temperature by fluid circulation electric heater.Slowly add the described crystallisate after drying in ethylene dibromide solution, stirring had demixing phenomenon in the dense medium after two hours.Topper mainly is an ammonium sulfate, if the owner of lower floor sodium sulfate.In the present embodiment, the drying step of the crystallisate behind the vanadium oxide factory effluent evaporative crystallization is carried out by fluid bed dryer, but industrially drying equipment is not limited thereto, and also can use equipment execution drying step such as whizzer.
The crystallisate that use dense medium separation method according to the present invention obtains after to vanadium oxide factory effluent evaporation concentration is handled, main component sodium sulfate is wherein separated with ammonium sulfate, thereby can utilize again them, avoid wherein ion finally to be discharged in the outside atmosphere and polluted with the form of obnoxious flavour.The employed equipment of this method is simple, technical process short, and energy consumption and processing cost are low, and can not cause secondary pollution in treating processes.
Claims (11)
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| CN2010102874435A CN101948211B (en) | 2010-09-20 | 2010-09-20 | Method for treating vanadium oxide production wastewater |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102249262A (en) * | 2011-04-29 | 2011-11-23 | 史永军 | Concentration and cold-precipitation separation method of sodium sulfate and ammonium sulfate from vanadium-precipitation mother liquor high-salt wastewater |
| CN102502900A (en) * | 2011-11-02 | 2012-06-20 | 攀钢集团研究院有限公司 | Treatment method of sodium-roasted-leached-acid ammonium salt vanadium precipitation waste water |
| CN103964624A (en) * | 2014-05-13 | 2014-08-06 | 攀钢集团攀枝花钢铁研究院有限公司 | Recycling method of ammonium salt precipitating vanadium wastewater |
| CN104150650A (en) * | 2014-08-15 | 2014-11-19 | 攀钢集团工程技术有限公司 | Method for electrochemically treating vanadium oxide production process wastewater |
| CN106915809A (en) * | 2017-04-07 | 2017-07-04 | 太平洋水处理工程有限公司 | A kind of formula of dense media powder for water process, preparation method and application method |
| CN113428877A (en) * | 2021-06-23 | 2021-09-24 | 攀枝花雅丰科技有限公司 | Method for recycling solid waste containing heavy metal, sodium salt and ammonium salt |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102249262A (en) * | 2011-04-29 | 2011-11-23 | 史永军 | Concentration and cold-precipitation separation method of sodium sulfate and ammonium sulfate from vanadium-precipitation mother liquor high-salt wastewater |
| CN102249262B (en) * | 2011-04-29 | 2012-11-21 | 史永军 | Concentration and cold-precipitation separation method of sodium sulfate and ammonium sulfate from vanadium-precipitation mother liquor high-salt wastewater |
| CN102502900A (en) * | 2011-11-02 | 2012-06-20 | 攀钢集团研究院有限公司 | Treatment method of sodium-roasted-leached-acid ammonium salt vanadium precipitation waste water |
| CN102502900B (en) * | 2011-11-02 | 2013-08-14 | 攀钢集团研究院有限公司 | Treatment method of sodium-roasted-leached-acid ammonium salt vanadium precipitation waste water |
| CN103964624A (en) * | 2014-05-13 | 2014-08-06 | 攀钢集团攀枝花钢铁研究院有限公司 | Recycling method of ammonium salt precipitating vanadium wastewater |
| CN103964624B (en) * | 2014-05-13 | 2016-04-27 | 攀钢集团攀枝花钢铁研究院有限公司 | A kind of method that ammonium salt vanadium wastewater recycles |
| CN104150650A (en) * | 2014-08-15 | 2014-11-19 | 攀钢集团工程技术有限公司 | Method for electrochemically treating vanadium oxide production process wastewater |
| CN106915809A (en) * | 2017-04-07 | 2017-07-04 | 太平洋水处理工程有限公司 | A kind of formula of dense media powder for water process, preparation method and application method |
| CN113428877A (en) * | 2021-06-23 | 2021-09-24 | 攀枝花雅丰科技有限公司 | Method for recycling solid waste containing heavy metal, sodium salt and ammonium salt |
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|---|---|
| CN101948211B (en) | 2012-04-04 |
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