The utility model content
The utility model proposes a kind of vanadium sodium separation device at defective that exists in the prior art or deficiency.Adopt described device, help solving at present in vanadium sodium separating technology, technological process is long, the energy consumption height, problems such as vanadium recovery is low help obtaining best vanadium sodium separating effect, improve the rate of recovery of vanadium, and technology is simple, and energy consumption is low, meets the policy of national energy-saving and emission-reduction.
Technical conceive of the present utility model is, adopts the film separation principle of NF membrane and south, road (Donnan) effect of NF membrane charged group, than realizing separating of different valence state ion vanadium and sodium in the vanadium sodium solution under the low operating pressure, thereby improves the rate of recovery of vanadium,
The technical solution of the utility model is as follows:
The vanadium sodium separation device, it is characterized in that, comprise the NF membrane piece-rate system, the stoste import of described NF membrane piece-rate system connects former liquid pipeline by compression pump, the sodium of described NF membrane piece-rate system sees through liquid and exports connection sodium through liquid pipeline, and the vanadium dope of described NF membrane piece-rate system reclaims a mouthful connection vanadium dope reclaim line.
The membrane module that described NF membrane piece-rate system adopts two or more NF membrane elements to be in series.
Described NF membrane piece-rate system adopts 4 membrane modules that the NF membrane element is in series.
Described compression pump adopts high-pressure pump, and the stoste entrance point of described high-pressure pump connects preposition filter, and described preposition filter connects the stoste case by booster pump.
Described preposition filter adopts microstrainer, is provided with the stoste control valve between described booster pump and the stoste case.
Described vanadium dope reclaim line connects circulation and takes off the sodium solution case, be provided with the dope control valve between the vanadium dope that sodium solution case and NF membrane piece-rate system are taken off in described circulation reclaims mouthful, described circulation is taken off the sodium solution case and is connected the stoste case by taking off sodium solution moisturizing circular treatment pipeline.
Vanadium sodium separation method, it is characterized in that, may further comprise the steps: will comprise in the stoste pressurization input NF membrane piece-rate system of vanadium sodium, the membrane module that is in series by the NF membrane element forms the reverse osmosis process and the Dao Nan effect of stoste, make the sodium ion in the stoste see through liquid and enter sodium, and the vanadium ion in the stoste is held back formation vanadium dope and is entered vanadium dope reclaim line by membrane module through liquid pipeline through membrane module formation sodium.
Described vanadium dope enters stoste after adding deionized water, the NF membrane separating treatment is carried out in circulation, realizes further taking off sodium.
When adopting nanofiltration membrane treatment vanadium sodium mixed solution, by regulating film turnover pressure, pH value and temperature, the single rejection of vanadium ion is up to 99.5~100%, single rejection≤8% of sodium ion; The circulation rejection of vanadium ion is up to 99.5~100%, and the circulation rejection of sodium ion is low to moderate 0.49%, thereby realizes the separation of vanadium sodium.
The described stoste that comprises vanadium sodium is carried out preposition filtration by booster pump input microstrainer, to remove behind the prejudicial material of membrane module, is pumped in the NF membrane piece-rate system by high-pressure pump again; The pressure limit of reverse osmosis concentrated solution side is 1.99~1.49MPa in the described membrane module, and transmembrane pressure is 0.05~0.21MPa; The aperture specification of described microstrainer is 4~6 μ m; Described stoste pH value is adjusted into 8.3~8.8.
Technique effect of the present utility model is as follows:
NF membrane to vanadium to hold back effect fine, can reach 100% basically, the rejection of sodium is very low, through having only 0.49% after eight circulations.Basically the rejection of single cycle has been passed through after eight circulations all below 8%, and total rejection of sodium reduces to 0.49%, has up to 99.51% sodium ion and separates through NF membrane and vanadium smoothly, has realized that basically vanadium sodium separates fully.
Vanadium sodium separation device of the present utility model has following characteristics:
(1) nanoscale aperture;
(2) operating pressure is low;
(3) has ion selectivity;
(4) pressure tightness and stronger contamination resistance preferably;
(5) can replace a plurality of steps in the conventional process, thus both economical.
The specific embodiment
Below in conjunction with accompanying drawing (Fig. 1-Fig. 2) the utility model is described.
The utility model proposes a kind of novel vanadium sodium separation device, can solve at present in vanadium sodium separating technology, technological process is long, the energy consumption height, problem such as vanadium recovery is low can obtain best vanadium sodium separating effect, improve the rate of recovery of vanadium, and technology is simple, and energy consumption is low, meets the policy of national energy-saving and emission-reduction.
As shown in Figure 1, the vanadium sodium separation device, comprise NF membrane piece-rate system 6, the stoste import of described NF membrane piece-rate system 6 connects former liquid pipeline by compression pump, the sodium of described NF membrane piece-rate system 6 sees through liquid and exports connection sodium through liquid pipeline, and the vanadium dope of described NF membrane piece-rate system 6 reclaims a mouthful connection vanadium dope reclaim line.The membrane module that described NF membrane piece-rate system 6 adopts two or more NF membrane elements to be in series.
Described NF membrane piece-rate system 6 adopts 4 membrane modules that the NF membrane element is in series.Described compression pump adopts high-pressure pump 5, and the stoste entrance point of described high-pressure pump 5 connects preposition filter, and described preposition filter connects stoste case 1 by booster pump 3.Described preposition filter adopts microstrainer 4, is provided with stoste control valve 2 between described booster pump 3 and the stoste case 1.Described vanadium dope reclaim line connects circulation and takes off sodium solution case 9, be provided with dope control valve 8 between the vanadium dope that sodium solution case 9 and NF membrane piece-rate system 6 are taken off in described circulation reclaims mouthful, described circulation is taken off sodium solution case 9 and is connected stoste casees 1 by taking off sodium solution moisturizing circular treatment pipeline 10.
Schematically illustrated the technological process of vanadium sodium separation method among Fig. 1 by the connecting line arrow.Vanadium sodium separation method, may further comprise the steps: will comprise in the stoste pressurization input NF membrane piece-rate system of vanadium sodium, the membrane module that is in series by the NF membrane element forms the reverse osmosis process and the Dao Nan effect of stoste, make the sodium ion in the stoste see through liquid and enter sodium, and the vanadium ion in the stoste is held back formation vanadium dope and is entered vanadium dope reclaim line by membrane module through liquid pipeline through membrane module formation sodium.Described vanadium dope enters stoste after adding deionized water, the NF membrane separating treatment is carried out in circulation, realizes further taking off sodium.
Fig. 2 is the infiltration pattern and the counter-infiltration pattern operation principle schematic diagram of NF membrane.As shown in Figure 2, the left-hand component among Fig. 2 is the infiltration pattern of NF membrane, and its infiltration direction 11 is to point to infiltration concentrated solution side 13 from infiltration weak solution side 15, and passes infiltration NF membrane 14.Right-hand component among Fig. 2 is the counter-infiltration pattern of NF membrane, and its counter-infiltration direction 12 is to point to infiltration weak solution sides 18 from infiltration concentrated solution side 19, and passes counter-infiltration NF membrane 17, has in infiltration concentrated solution side 19 to be labeled as 16 pressurization operation or setting.
Membrane separation process is to utilize special film that some composition in the liquid is carried out a kind of method of selective permeation, has characteristics such as energy-conservation, efficient, is the new and high technology that solves significant problems such as contemporary mankind's energy crisis and environmental pollution.The NF membrane operation principle is to apply operating pressure in water inlet (concentrated solution) side to press to overcome naturally osmotic, when the operating pressure that is higher than the naturally osmotic pressure puts on the concentrated solution side, the flow direction of hydrone naturally osmotic will reverse, and the hydrone part in the water inlet (concentrated solution) is produced water by the purification that film becomes the weak solution side.See Fig. 2.
Bibliographical information is not seen in the research of adopting the NF membrane principle to separate vanadium sodium at home and abroad as yet.
Characteristics of NF membrane are to have ion selectivity: the clearance of the infiltrate film that monovalent ion can be a large amount of (but being not unobstructed) multivalent ion (for example sulfate and carbonate) is then much higher.Therefore the permeability of salt is mainly determined by the valence state of ion.
For anion, clearance rises in the following order: NO
3-<Cl
-<OH-<SO
4 2-<CO
3 2-
For cation, clearance rises in the following order: H
+<Na
+<K
+<Ca
2+<Mg
2+
Why nanofiltration process has ion selectivity, is that they hinder the infiltration of multivalent ion by electrostatic interaction because charged group is arranged on film or in the film.Difference of charge (as positive electricity or negative electricity) and charged density not equal all can produce significantly influence to film properties.
The mechanism of mass transfer of NF membrane can explain that most of NF membrane is charged type with solubility-diffusion model, and its separating behavior to inorganic salts is controlled by chemical potential not only, also is subjected to the influence of potential gradient simultaneously, and south, concrete available road (Donnan) balance is explained.So-called Donnan balance is meant that in seeing through film system when film both sides solution was in balance, not only chemical potential equated, and must be electroneutral.Positive charge ion can see through film in the water under the concentration difference effect, but negatively charged ions is subjected to the retardance of electronegative film, can't (or seldom) reach dilute side through film, because elrectroneutrality pcharge-neutrality principle, limited positive charge ion again and spread to dilute side, this has just reached the purpose of desalination.Compare with monovalent ion, divalent ion is because electric charge is many, and elrectroneutrality pcharge-neutrality principle causes the resistance of concentration difference diffusion bigger, also more difficultly sees through film, so NF membrane is greater than removal efficiency to monovalent ion to bivalent ions removal efficiency.
Because inorganic salts can see through NF membrane, make its osmotic pressure low, so in flux one timing more than reverse osmosis membrane, the required impressed pressure of NF membrane process is more much lower than counter-infiltration; And with under the equal pressure, the flux ratio R counter-infiltration of nanofiltration is much bigger.In addition, nanofiltration can make to concentrate with desalination and carry out synchronously.So when replacing counter-infiltration with nanofiltration, concentration process can carry out effectively and quickly, and reaches bigger cycles of concentration.
Technique effect of the present utility model is as follows:
When adopting nanofiltration membrane treatment vanadium sodium mixed solution, by regulating film turnover pressure, pH value and temperature, the single rejection of vanadium reaches 100% basically, single rejection≤8% of sodium; The circulation rejection of vanadium reaches 100%, and the circulation rejection of sodium can reach 0.49%, has realized effective separation of vanadium sodium basically.
This experiment changes conditions such as pressure, flow, investigates the Changing Pattern of Na ion concentration and vanadium concentration in the nanofiltration processing procedure, and what calculate this NF membrane takes off sodium effect and vanadium damaed cordition.
Experiment flow as shown in Figure 1, former water feed liquid pumps into pretreatment system through former water regulating valve by booster pump.Pretreatment system is a microstrainer that the aperture is 5 μ m, and former water is removed behind the prejudicial material of membrane module through microstrainer, pumps into membrane module by high-pressure pump again.
Membrane module is in series by 4 NF membrane elements.Former water is entered by the water inlet end of NF membrane element, and the infiltration of the NF membrane element of process series connection produces penetrating fluid.Because the cutoff performance of film, the material permeance films such as sodium ion that water and molecular weight are very little form and see through liquid, are transferred or discharge.Other macromolecular relatively vanadic acid roots then are trapped, and form vanadium removal solution, through the overrich water regulating valve, are recovered to the water tank that takes off sodium solution.If taking off of this moment still contains sodium in the sodium solution, it is incomplete to take off sodium, need add and penetrating fluid equivalent deionized water, carries out the NF membrane separating treatment once more, and circulation is until reaching the requirement that vanadium sodium separates.
Experimental procedure is as follows:
(1) in raw water box, adds feed liquid 110L, drive booster pump.
(2) drive high-pressure pump, simulate pressure, the flow condition of four NF membrane element series connection.
(3) temperature, the pH of the former water of measurement, concentrated solution discharge, permeate flow.
(4) after former water treatment finishes, measure the volume of penetrating fluid.
(5) emit penetrating fluid, in taking off sodium solution, add and the isopyknic deionized water of penetrating fluid, measure the vanadium concentration and the na concn that take off this moment in the sodium solution.
(6) repeat (1)~(5) experimentation, do circulation experiment, till the requirement that reaches experimental result.
Advantage of the present utility model:
(1) nanoscale aperture
NF membrane is a kind of film between reverse osmosis membrane and milipore filter, its surface apertures is in nanoscale scope (10-9m), hold back relative molecular mass (MWCO) between 200~1000, be suitable for separating relative molecular mass more than 200, the molecular particle size size is about the dissolved constituent of 1nm.RO removes all salt and organic matter, and UF does not hold back effect to salt and low molecule organic matter, and NF membrane can be held back low molecule organic matter and multivalent salts.The UF-milipore filter.The RO-reverse osmosis membrane.The NF-NF membrane.
(2) operating pressure is low
Counter-infiltration (RO) process action required pressure is very high, generally between several even tens MPas.NF is lower than the desired operating pressure of RO, common NF separates the transmembrane pressure that needs can be 0.01~2.0MPa, hang down 0.5-3.0MPa than reach the pressure reduction that same permeation flux institute must apply with RO, thereby be also referred to as " low pressure reverse osmosis " (Low press RO).Operating pressure reduces the reduction that then means the requirement of system dynamic equipment, and this is favourable for the equipment investment expense that reduces entire separation system.
(3) has ion selectivity
Owing to often have charged group on film or in the film, by electrostatic interaction, produce the Donnan effect, to containing the multicomponent system solution of different valence state ion, can realize the separation of different valence state ion, so also claim " selectivity counter-infiltration " (Selective RO) sometimes.In general, NF membrane is 10%~80% only to the rejection of monovalent salt, have sizable permeability, and the rejection of divalence and multivalent salts is all more than 90%.
(4) pressure tightness and stronger contamination resistance preferably
Because NF membrane mostly is composite membrane and charged membrane, thereby its pressure tightness and contamination resistance are strong, and in addition, charged nanofiltration membrane can separate with high valence ion the low price ion according to the size of ion and the height of electricity price.
(5) can replace a plurality of steps in the conventional process, thus both economical
For example, for water being softened and purifying, often adopt lime-soda process or ion-exchange to remove Ca
2+, Mg
2+Deng divalent ion, remove organic matter with active carbon adsorption.This water treatment procedure technology is loaded down with trivial details, and efficient is low, the expense height.And adopt nanofiltration just can disposable above-mentioned substance to be removed simultaneously.
Case
Experimental water adopts the vanadium sodium solution in vanadium chemical plant, and its correlation water index sees Table 1.
Table 1 experiment water quality
In experiment, add feed liquid 110L at every turn, material liquid component such as table 1 wherein contain vanadium 16.50g/L, and that sodium 12.80g/L, membrane component select for use is the highest DK2540F of salt rejection rate.Carried out circulation experiment altogether eight times, experimental result sees Table 2~9.
The table 2NF film vanadium sodium separating resulting that circulates for the first time
Annotate: vanadium, na concn are to add concentration behind the steady seepage liquid deionized water (down with) in the table
The table 3NF film vanadium sodium separating resulting that circulates for the second time
The table 4NF film vanadium sodium separating resulting that circulates for the third time
Membrane module |
Pressure/(advance/go out, |
pH |
Temperature |
Flow/(it is dense/rare, |
Vanadium |
Sodium |
The penetrating fluid volume |
|
MPa) |
|
/(℃) |
LPM) |
/(g/L) |
/(g/L) |
/(L) |
First element |
1.65/1.55 |
8.47 |
30.0 |
12.85/1.70 |
- |
- |
- |
Second element |
1.65/1.55 |
8.49 |
30.0 |
12.85/1.85 |
- |
- |
- |
Three element |
1.67/1.60 |
8.49 |
31.0 |
12.85/1.50 |
- |
- |
- |
The quaternary part |
1.67/1.60 |
8.49 |
31.0 |
12.85/1.41 |
16.50 |
0.61 |
35.00 |
The 4th circulation vanadium sodium of table 5NF film separating resulting
The 5th circulation vanadium sodium of table 6NF film separating resulting
The 6th circulation vanadium sodium of table 7NF film separating resulting
The 7th circulation vanadium sodium of table 8NF film separating resulting
The 8th circulation vanadium sodium of table 9NF film separating resulting
Separate eight circulation experiment data of vanadium sodium from NF membrane, can draw the effect that the method is separated vanadium sodium, shown in table 3-11.
Table 10 NF membrane is separated the effect of vanadium sodium
As can be seen from Table 10, NF membrane to vanadium to hold back effect fine, can reach 100% basically, the rejection of sodium is very low, through having only 0.49% after eight circulations.Basically the rejection of single cycle has been passed through after eight circulations all below 8%, and total rejection of sodium reduces to 0.49%, has up to 99.51% sodium ion and separates through NF membrane and vanadium smoothly, has realized that basically vanadium sodium separates fully.