CN111825152A - Belt filter and application thereof in adsorption method brine lithium extraction - Google Patents
Belt filter and application thereof in adsorption method brine lithium extraction Download PDFInfo
- Publication number
- CN111825152A CN111825152A CN202010646187.8A CN202010646187A CN111825152A CN 111825152 A CN111825152 A CN 111825152A CN 202010646187 A CN202010646187 A CN 202010646187A CN 111825152 A CN111825152 A CN 111825152A
- Authority
- CN
- China
- Prior art keywords
- salt
- liquid
- lithium
- adsorbent
- desorption
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/28—Treatment of water, waste water, or sewage by sorption
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D15/00—Lithium compounds
- C01D15/02—Oxides; Hydroxides
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D15/00—Lithium compounds
- C01D15/08—Carbonates; Bicarbonates
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
Abstract
The invention discloses a belt filter and application thereof in extraction of lithium from brine by an adsorption method, wherein the belt filter comprises a frame, filter cloth which rotates to and fro is arranged on the frame, and the filter cloth is sequentially arranged along the advancing direction of the filter cloth: the solid-liquid separation area is provided with a mixed adsorption mechanism for conveying an adsorbent brine mixture to the solid-liquid separation area; the salt washing area is provided with a salt washing liquid conveying mechanism for conveying the salt washing liquid to the salt washing area; and a desorption liquid conveying mechanism for conveying desorption liquid to the desorption area is distributed above the desorption area, and a lithium eluent collecting port is arranged below the desorption area. The adsorption method for extracting lithium from brine by using the belt filter has low cost, can obtain lithium eluent with magnesium-lithium ratio of less than 1:1 and salt-lithium ratio of less than 10:1, has the lithium recovery rate of more than 70 percent, and greatly reduces the investment and production cost of the subsequent desalting and purifying process.
Description
Technical Field
The invention belongs to the technical field of lithium extraction from brine, and particularly relates to a belt filter and application thereof in lithium extraction from brine by an adsorption method.
Background
The rapid development of the current new energy industry drives the rapid increase of the demand of lithium products, but the high concentration of global lithium resources leads the global lithium product production to have the situation of oligopolism, which leads China to rely on import for a long time in lithium product supply. Along with the increasing importance of China on the development of lithium resources, China has found that the reserve of the lithium resources is 4008 ten thousand tons in terms of lithium chloride, wherein the salt lake resources account for about 71 percent and the ore resources account for about 29 percent, so that the lithium extraction from the salt lake brine has great significance for guaranteeing the development of new energy industries in China.
The selective adsorption method is a main means for extracting lithium from the salt lake brine at present, and can adsorb and separate lithium from a mixed solution containing various ions, and then the lithium ions can be separated from other ions by elution. Because the adsorption method is similar to the traditional water treatment method, the equipment used in the existing lithium extraction adsorption process of brine is basically from the traditional water treatment industry, wherein the adsorption tower is the most common, and molecular sieves or ion sieve type adsorbents such as aluminum series, monoclinic antimonate series, titanate series, manganese oxide series and the like are matched with the adsorption tower. The crystal structure of the selective adsorption material contains a gap structure matched with lithium ions, so that the selective adsorption material has specific selective adsorption on the lithium ions under the condition that various ions exist.
However, many practical problems have been found in the use of selective adsorbents in adsorption columns for lithium extraction from brines: (1) the used selective adsorbent has low capacity, the working capacity is generally less than 10mg/g, the activity is greatly reduced after granulation, and the selective adsorbent is fragile and easy to run off; (2) the quantity of water of thousands of cubic meters is required in the process of extracting lithium from brine per hour, which causes great load on the operation of the adsorption tower; (3) in the production stage, a large number of adsorption towers filled with the adsorbent are required to be constructed, the investment cost is high, thousands of tons of adsorbents are required to be reserved in the investment stage of a ten thousand-ton lithium carbonate production line, and the price is as high as hundreds of millions of yuan; (4) the salt-lithium ratio in the obtained lithium eluent is more than 30:1, and the magnesium-lithium ratio is more than 3:1, which brings great difficulty to the subsequent desalting and purifying process, and the finally obtained lithium product is extremely difficult to meet the requirement of battery-grade lithium carbonate or lithium hydroxide on the content of impurities; (5) more than 20% of lithium ions can be lost in the washing section, so that the lithium recovery rate in the adsorption section is lower than 60%, the lithium recovery rate in the whole process section is lower than 50%, and if high lithium recovery rate is to be obtained, multi-tower series connection and function conversion are required, so that the difficulty of industrial continuous production is greatly increased.
In recent years, there has been reported a method for extracting lithium from brine by using a powder adsorbent, which does not require granulation, has a much higher adsorption capacity than a granular adsorbent, and can significantly reduce the adsorption reaction time and the amount of the adsorbent used. At present, there are documents or patent reports that powder adsorbent is combined with plate-and-frame filter press, centrifuge, precise filtration or ceramic membrane for adsorption and desorption. However, the existing operation lacks understanding and attention on the washing process of the adsorbent in the process of extracting lithium from brine, so that the existing lithium extracting process from brine cannot obtain lithium eluent with low salt-lithium ratio.
Disclosure of Invention
The invention aims to provide a belt filter and application thereof in extraction of lithium from brine by an adsorption method.
In order to achieve the purpose, the technical scheme of the invention is as follows:
the utility model provides a band filter, includes the frame, the frame on be equipped with the filter cloth of reciprocal rotary motion, be equipped with in proper order along filter cloth advancing direction:
the solid-liquid separation area is provided with a mixed adsorption mechanism for conveying an adsorbent brine mixture to the solid-liquid separation area;
the salt washing area is provided with a salt washing liquid conveying mechanism for conveying the salt washing liquid to the salt washing area;
and a desorption liquid conveying mechanism for conveying desorption liquid to the desorption area is distributed above the desorption area, and a lithium eluent collecting port is arranged below the desorption area.
It is known that the total salinity of brine can reach hundreds of grams per liter, and the lithium content is only tens to hundreds of milligrams per liter. Through a large number of research experiments, patentees find that how to reduce the ratio of lithium salt in lithium eluent to the maximum extent is the key of extracting lithium from brine by an adsorption method in the process of extracting lithium from brine by the adsorption method. The lithium eluent with low salt-lithium ratio means that the impurity content in the product of the adsorption method is low, the subsequent processing flow is simple, the cost is low, and the purity of the final lithium carbonate product is high.
The research of patentees shows that in the adsorption process, the lithium ions are subjected to intercalation reaction at the interface of the adsorbent, and other salt ions cannot enter the interlayer of the selective adsorbent and only interface adsorption occurs. This results in different binding strengths between the lithium ion and other salt ions and the adsorbent.
The applicant modifies the traditional belt type vacuum filter (namely a belt filter) and applies the conventional belt type vacuum filter to the process of extracting lithium from brine by an adsorption method for the first time. According to different mechanisms arranged above the filter cloth, a solid-liquid separation zone, a salt washing zone and a desorption zone are formed on the filter cloth in sequence along the advancing direction of the filter cloth; wherein, in the solid-liquid separation zone, the mixed adsorption mechanism pre-mixes the adsorbent and the raw material brine to ensure that the adsorbent fully adsorbs lithium ions in the brine; then, conveying the adsorbent brine mixture to filter cloth of a solid-liquid separation zone to separate the adsorbent from the brine, wherein the adsorbent is left on the filter cloth, and the brine is filtered through the filter cloth; in the salt washing area, the salt washing liquid conveying mechanism conveys the salt washing liquid to the adsorbent on the filter cloth so as to elute ions, except lithium, adsorbed on the adsorbent; and in the desorption area, a desorption liquid conveying mechanism conveys desorption liquid to the adsorbent on the filter cloth so as to elute lithium ions adsorbed on the adsorbent, and the lithium eluent filtered by the filter cloth is collected through a lithium eluent collecting port.
The whole salt washing process is carried out in the dynamic operation process of the filter cloth, so the contact time of the salt washing liquid and the adsorbent is short, the salt washing liquid can take away salt ions to the maximum extent and take away lithium ions to the minimum extent through the adsorbent, and the purpose of 'throwing salt and leaving lithium' is achieved; in the salt washing area, the salt ions which are weakly combined with the adsorbent are eluted first, and in the desorption area, the lithium ions which are strongly combined with the adsorbent are eluted, so that the separation of salt and lithium is realized to the maximum extent. By adopting the belt filter, the lithium eluent with the magnesium-lithium ratio of less than 1:1 and the salt-lithium ratio (TDS/Li) of less than 10:1 can be obtained, the lithium recovery rate reaches more than 70%, the investment and production cost of the subsequent desalting purification process are greatly reduced, the difficulty of the subsequent desalting purification process is reduced, and finally, the battery-grade lithium carbonate or lithium hydroxide can be stably obtained.
In addition, the belt filter uses the powdery lithium ion selective adsorbent, granulation of the adsorbent is not needed before use, the amount of the adsorbent loaded once in the use process is greatly reduced compared with that of an adsorption tower, the investment cost in the production stage is greatly reduced, the addition amount of the adsorbent in a ten thousand-ton lithium carbonate production line is only 300-.
In the belt filter, a brine recovery port is arranged below the solid-liquid separation zone, a salt-eluting liquid collection port is arranged below the salt-eluting zone, and at least the salt-eluting liquid collection port is connected with a vacuumizing mechanism among the brine recovery port, the salt-eluting liquid collection port and the lithium-eluting liquid collection port;
at least one of the brine recovery port, the salt eluent collection port and the lithium eluent collection port is connected with an adsorbent recovery mechanism.
Applicants have found that the adsorbent that has captured lithium ions still suffers from lithium ion loss during salt washing, but the shorter the washing time, the lower the rate of lithium ion loss. Therefore, the invention is provided with the vacuum pumping mechanism at least at the salt eluent collecting opening, and the vacuum pumping mechanism can increase the speed of the salt washing liquid passing through the adsorbent, shorten the contact time of the salt washing liquid and the adsorbent and reduce the lithium amount taken away by the salt washing liquid as much as possible.
Of course, a brine recovery port can be arranged below the solid-liquid separation zone, and a vacuumizing mechanism can be arranged at the brine recovery port and the lithium eluent collection port, so that the working efficiency of the belt filter is improved.
Because the invention uses the powder adsorbent, the percentage interception of the filter cloth is difficult to realize, therefore, the invention sets up the adsorbent recovery mechanism in at least one place of brine recovery mouth, salt eluent collection mouth and lithium eluent collection mouth, in order to reclaim the adsorbent in brine, salt eluent and lithium eluent, save the adsorbent cost.
The adsorbent recovery mechanism can adopt powder material recovery equipment common in the prior art, such as a magnetic separator, a precision filter, a ceramic membrane and the like.
In order to improve the salt washing efficiency, in the belt filter, the salt washing liquid conveying mechanism is provided with at least two liquid outlet ends arranged along the advancing direction of the filter cloth. The liquid outlet ends arranged along the advancing direction of the filter cloth can realize 'salt washing for a plurality of times with small dosage', compared with a single liquid outlet end, the liquid outlet ends are arranged to achieve the same salt washing effect, the using amount of the salt washing liquid is less, the lithium loss amount is lower, and higher salt washing efficiency can be obtained under the condition that the same amount of the salt washing liquid is adopted.
Similarly, the applicant also found that the adsorbent which has captured lithium ions still has lithium ion loss during the salt washing process, but the higher the salt concentration of the salt washing solution, the lower the lithium ion loss rate. Therefore, in the belt filter, the salt concentration of the salt washing solution conveyed from the liquid outlet end is gradually increased along the direction opposite to the advancing direction of the filter cloth.
The higher the concentration of lithium ions on the adsorbent in the direction opposite to the filter cloth advancing direction, the salt concentration of the salt washing solution is correspondingly set to be eluted in a gradient from low to high so as to reduce the loss of lithium ions on the adsorbent as much as possible.
Preferably, in the belt filter, the salt washing liquid conveying mechanism comprises a salt washing liquid primary supply assembly and at least one salt washing liquid circulating assembly, and the salt washing liquid primary supply assembly and the salt washing liquid circulating assembly are sequentially connected in series along the direction opposite to the advancing direction of the filter cloth;
the salt washing liquid circulation assembly is characterized in that the liquid outlet ends of the salt washing liquid primary supply assembly and the salt washing liquid circulation assembly are both positioned above the salt washing area, salt eluent collecting openings corresponding to the liquid outlet ends are arranged below the salt washing area, the liquid inlet end of the salt washing liquid primary supply assembly is connected with a salt washing liquid storage tank, and the liquid inlet end of the salt washing liquid circulation assembly is connected with a salt eluent collecting opening corresponding to the salt washing liquid primary supply assembly or the previous salt washing liquid circulation assembly.
The supply of the salt washing liquid is carried out along the reverse direction of the advancing direction of the filter cloth, the salt washing liquid of the salt washing liquid circulating assembly is collected from a salt washing liquid collecting port of the salt washing liquid primary supply assembly or the previous salt washing liquid circulating assembly, and the salt washing liquid passes through at least one time of salt washing, so the salt concentration of the salt washing liquid at the liquid outlet end of the salt washing liquid circulating assembly is always higher than that of the salt washing liquid primary supply assembly or the previous salt washing liquid circulating assembly, and the reverse elution of the concentration gradient of the salt washing liquid is realized.
The salt washing liquid supplies the series connection of subassembly and at least one salt washing liquid circulation subassembly for whole salt washing liquid conveying mechanism only needs to set up a salt washing liquid storage tank and supplies the salt washing liquid, has both simplified overall structure, has practiced thrift the salt washing liquid quantity, can realize the disposable collection of salt eluant again.
Likewise, in the belt filter described above, the desorption liquid conveying mechanism has at least two liquid outlet ends arranged along the filter cloth advancing direction. The liquid outlet ends arranged along the advancing direction of the filter cloth can realize 'small-dose multiple desorption', compared with a single liquid outlet end, the liquid outlet ends are arranged to achieve the same desorption effect, the consumption of desorption liquid is less, and higher desorption efficiency can be obtained under the condition of adopting the same amount of desorption liquid.
Preferably, in the belt filter, the desorption liquid conveying mechanism comprises a desorption liquid initial supply component and at least one desorption liquid circulation component, and the desorption liquid initial supply component and the desorption liquid circulation component are sequentially connected in series along the direction opposite to the advancing direction of the filter cloth;
the desorption liquid supplies the subassembly for the first time and desorbs liquid circulation subassembly's play liquid end all be in desorption district top, desorption district below be equipped with each play liquid end corresponding lithium eluant collection mouth, desorption liquid supply the liquid inlet end of subassembly for the first time and desorb liquid storage tank and link to each other, desorption liquid circulation subassembly's liquid inlet end and desorb liquid supply the subassembly for the first time or last desorption liquid circulation subassembly corresponding lithium eluant collection mouth link to each other.
The applicant has found that the lower the salt ion concentration in the desorption solution, the higher the lithium elution efficiency. Therefore, the desorption liquid primary supply component and the desorption liquid circulating component are sequentially connected in series along the reverse direction of the filter cloth advancing direction, and the concentration of salt ions on the filter cake is lower and lower along the filter cloth advancing direction, so that the concentration of the salt ions in the lithium eluent is lower and lower along the filter cloth advancing direction; when the reverse elution is carried out, the 'low-salt lithium washing' is realized, and the consumption of the desorption liquid is greatly saved.
The invention also provides an application of the belt filter in extraction of lithium from adsorption-process brine, which comprises the following steps:
(1) uniformly mixing an adsorbent and brine in the mixed adsorption mechanism;
(2) conveying the adsorbent brine mixture to a solid-liquid separation zone, separating the adsorbent from brine and preparing the adsorbent into a filter cake on filter cloth;
(3) the filter cake moves to a salt washing area along with the filter cloth, and in the salt washing area, the salt washing liquid conveying mechanism conveys the salt washing liquid to the filter cake to enable ions adsorbed on the filter cake except lithium to be eluted, and salt eluent is collected;
(4) the filter cake moves to a desorption area along with the filter cloth, and in the desorption area, the desorption liquid conveying mechanism conveys desorption liquid to the filter cake to enable lithium ions adsorbed on the filter cake to be eluted, and lithium eluent is collected;
(5) and at the end point of the advancing direction of the filter cloth, collecting the desorbed adsorbent and conveying the adsorbent to a mixed adsorption mechanism for a new cycle of lithium extraction from the brine by an adsorption method.
The research of patentees finds that the adsorbent can quickly collect lithium ions in a high-salt-concentration solution, and the adsorption balance of the adsorbent can reach more than 60% within tens of seconds of contact time when the solid-liquid ratio is high. Therefore, in the belt filter, a salt washing water return area is further arranged at the downstream of the desorption area, a salt eluent backflow mechanism is arranged above the salt washing water return area, and the liquid inlet end of the salt eluent backflow mechanism is connected with the salt eluent collection port;
and an adsorbent recovery mechanism is arranged at the downstream of the salt washing water return area and is connected with the mixed adsorption mechanism.
And the salt eluent collected from the salt washing area is sent to the salt washing water return area through the salt eluent backflow mechanism, so that the adsorbent passing through the salt washing area and the desorption area adsorbs the salt solution again, lithium in the salt eluent can be recovered again, and when the part of adsorbent is sent back to the mixed adsorption mechanism through the adsorbent recovery mechanism to be mixed with brine, the adsorbent adsorbing high-concentration salt can quickly capture lithium ions in the brine, and the next round of adsorption method brine lithium extraction is implemented.
In this case, the application of the belt filter in the lithium extraction from the adsorption brine comprises the following steps:
(1) uniformly mixing an adsorbent and brine in the mixed adsorption mechanism;
(2) conveying the adsorbent brine mixture to a solid-liquid separation zone, separating the adsorbent from brine and preparing the adsorbent into a filter cake on filter cloth;
(3) the filter cake moves to a salt washing area along with the filter cloth, and in the salt washing area, the salt washing liquid conveying mechanism conveys the salt washing liquid to the filter cake to enable ions adsorbed on the filter cake except lithium to be eluted, and salt eluent is collected;
(4) the filter cake moves to a desorption area along with the filter cloth, and in the desorption area, the desorption liquid conveying mechanism conveys desorption liquid to the filter cake to enable lithium ions adsorbed on the filter cake to be eluted, and lithium eluent is collected;
(5) conveying the salt eluent collected in the step to a salt washing water return area to pre-adsorb the adsorbent;
(6) and collecting the pre-adsorbed adsorbent at the end point of the advancing direction of the filter cloth, conveying the adsorbent to a mixed adsorption mechanism, and performing a new round of lithium extraction from the adsorption brine.
In the application of the belt filter in the adsorption method brine lithium extraction, the contact time of the salt washing liquid or the desorption liquid and the filter cake is not more than 10 seconds.
Preferably, in the application of the belt filter in the extraction of lithium from adsorption brine, the contact time of the salt washing liquid or the desorption liquid and the filter cake is 1-2 s.
Compared with the prior art, the invention has the beneficial effects that:
(1) the applicant reconsiders the adsorption mechanism of the lithium ion selective adsorbent, finds that the bonding strength between lithium ions and other salt ions and the adsorbent is different, modifies the traditional belt filter accordingly, and applies the modified belt filter to the adsorption method brine lithium extraction process for the first time. According to different mechanisms arranged above the filter cloth, a solid-liquid separation zone, a salt washing zone and a desorption zone are formed on the filter cloth in sequence along the advancing direction of the filter cloth; in the solid-liquid separation zone, the adsorbent is separated from the brine and made into a filter cake; in a salt washing area, the salt washing liquid is used for eluting ions except lithium on the filter cake; in the desorption area, the desorption liquid elutes the lithium ions on the filter cake; the whole salt washing process is carried out in the dynamic operation process of the filter cloth, so the contact time of the salt washing liquid and the adsorbent is short, the salt washing liquid can take away salt ions to the maximum extent and take away lithium ions to the minimum extent through the adsorbent, and the purpose of 'throwing salt and leaving lithium' is achieved; because the salt ions which are weakly combined with the adsorbent are eluted firstly in the salt washing area and the lithium ions which are strongly combined with the adsorbent are eluted in the desorption area, the separation of the salt and the lithium is realized to the maximum extent. By adopting the belt filter, the lithium eluent with the magnesium-lithium ratio of less than 1:1 and the salt-lithium ratio of less than 10:1 can be obtained, the lithium recovery rate reaches more than 70%, the investment and production cost of the subsequent desalting purification process are greatly reduced, the difficulty of the subsequent desalting purification process is reduced, and finally, the battery-grade lithium carbonate or lithium hydroxide can be stably obtained.
(2) The belt filter provided by the invention uses the powdery lithium ion selective adsorbent, granulation of the adsorbent is not needed before use, the amount of the adsorbent loaded once in the use process is greatly reduced compared with that of an adsorption tower, the investment cost in the production stage is greatly reduced, the addition amount of the adsorbent in a ten thousand ton lithium carbonate production line is only 300-.
(3) In the belt filter, at least a vacuumizing mechanism is arranged at the salt eluent collecting opening; the vacuumizing mechanism can increase the speed of the salt washing liquid passing through the adsorbent, shorten the contact time of the salt washing liquid and the adsorbent, and reduce the lithium amount taken away by the salt washing liquid as much as possible.
(4) In the belt filter, at least one of the brine recovery port, the salt eluent collection port and the lithium eluent collection port is provided with the adsorbent recovery mechanism, and the adsorbent recovery mechanism is used for recovering the adsorbent in the brine, the salt eluent and the lithium eluent, so that the cost of the adsorbent is saved.
(5) In the belt filter, the salt washing liquid conveying mechanism is provided with at least two liquid outlet ends arranged along the advancing direction of the filter cloth; the liquid outlet ends arranged along the advancing direction of the filter cloth can realize 'salt washing for a plurality of times with small dosage', the salt washing efficiency is improved, and compared with a single liquid outlet end, the liquid outlet ends are arranged, the salt washing liquid is less in dosage and lower in lithium loss while the same salt washing effect is achieved.
(6) In the belt filter, the salt concentration of the salt washing solution conveyed by the liquid outlet end is gradually increased along the direction opposite to the advancing direction of the filter cloth, so that gradient salt washing is realized, and the loss of lithium ions on the adsorbent is reduced as much as possible.
(7) In the belt filter, the desorption liquid conveying mechanism is provided with at least two liquid outlet ends arranged along the advancing direction of the filter cloth; the liquid outlet ends arranged along the advancing direction of the filter cloth can realize 'small-dose multiple desorption', the desorption efficiency is improved, and compared with a single liquid outlet end, the liquid outlet ends are arranged to achieve the same desorption effect, and the consumption of desorption liquid is less.
(8) In the belt filter, the lower stream of the desorption area is also provided with a salt washing water return area, salt eluent collected from the salt washing area is sent to the salt washing water return area through a salt eluent backflow mechanism, so that the adsorbents passing through the salt washing area and the desorption area can adsorb salt solution again, lithium in the salt eluent can be recovered again, and when the part of the adsorbents are sent back to the mixed adsorption mechanism through the adsorbent recovery mechanism to be mixed with brine, the adsorbents adsorbing high-concentration salt can quickly capture lithium ions in the brine, and the next round of brine extraction by an adsorption method is implemented.
Drawings
FIG. 1 is a schematic view of the belt filter of the present invention;
FIG. 2 is another schematic view of the belt filter of the present invention;
FIG. 3 is a schematic diagram of a second configuration of the salt-scrubbing and desorption zones of the belt filter of the present invention;
FIG. 4 is a schematic diagram of a third configuration of the salt-scrubbing zone and the desorption zone of the belt filter of the present invention.
Detailed Description
The technical solution of the present invention will be further described in detail with reference to the accompanying drawings and the detailed description.
Example 1
As shown in fig. 1, the belt filter of this embodiment is obtained by improving an existing belt vacuum filter, and the focus of this embodiment is detailed on the improvement, and other undescribed parts are the same as the structure of the existing belt vacuum filter on the market, and are not described again in this embodiment.
As shown in fig. 1, the belt filter of the present embodiment includes a frame 1, a filter cloth 2 for reciprocating and revolving operation is disposed on the frame 1, the reciprocating and revolving operation of the filter cloth 2 is driven by a driving mechanism 3 disposed on the frame 1, and the driving mechanism 3 may include conventional: a driving wheel 31 and a driven wheel 32 rotatably connected to the frame 1, wherein the driving wheel 31 is driven by a circumferential driver (not shown), and the filter cloth 2 is surrounded between the driving wheel 31 and the driven wheel 32.
The filter cloth 2 of the embodiment is preferably a filter cloth 2 with large ventilation volume, and the ventilation volume of the filter cloth 2 is more than 500L/m2S and a retention on the adsorbent of greater than 90%.
As shown in fig. 1, a liquid collecting box 4 positioned below the filter cloth 2 is fixedly installed on the frame 1 between the driving wheel 31 and the driven wheel 32, the top of the liquid collecting box 4 may be provided with an opening, or may not be provided with an opening, but the top of the liquid collecting box 4 is provided with a plurality of filter holes; whether the liquid collecting box is opened or not, a blocking mechanism (not shown in the figure) should be arranged at the top of the liquid collecting box 4, so that liquid is prevented from leaking from two sides of the top of the liquid collecting box 4, and the liquid is ensured to completely enter the liquid collecting box 4.
As shown in fig. 1, a solid-liquid separation zone 100, a salt washing zone 200, and a desorption zone 300 are formed in the frame 1 in this order along the forward direction of the filter cloth 2, depending on the mechanism provided above the filter cloth 2. In order to adapt to the subareas, the liquid collection box 4 is also internally provided with partition plates 41 which are uniformly arranged along the advancing direction of the filter cloth 2, and the partition plates 41 divide the liquid collection box 4 into a plurality of liquid collection cavities 42; the lengths of the solid-liquid separation zone 100, the salt washing zone 200 and the desorption zone 300 are all multiples of the length of the liquid collection chamber 42, and of course, the specific multiples of the solid-liquid separation zone 100, the salt washing zone 200 and the desorption zone 300 may be the same or different, depending on the specific design requirements.
As shown in FIG. 1, in the present embodiment, the solid-liquid separation zone 100 has a length corresponding to the length of four liquid collecting chambers 42, and the salt washing zone 200 and the desorption zone 300 have a length corresponding to the length of three liquid collecting chambers 42. The length of each functional area is set to be the multiple of the length of the liquid collecting cavity 42, so that the corresponding liquid of each functional area can enter the corresponding liquid collecting cavity 42.
In this embodiment, the length of the liquid collection chamber 42 can be specifically set according to specific needs.
As can be seen from FIG. 1, in the three functional zones of this embodiment, a mixing and adsorbing mechanism 5 is arranged above the filter cloth 2 in the solid-liquid separation zone 100; the mixed adsorption mechanism 5 comprises a mixing tank 51, the top of the mixing tank 51 is provided with a brine feed port 52 and an adsorbent feed port 53, raw brine and an adsorbent respectively enter the mixing tank 51 through the corresponding feed ports, and under the action of a stirring assembly 54, the adsorbent and the raw brine are mixed and adsorbed in the mixing tank 51 to obtain an adsorbent brine mixture; the adsorbent brine mixture is discharged from the mixing tank 51 and is conveyed to the filter cloth 2 of the solid-liquid separation zone 100; due to the filtering effect of the filter cloth 2, the adsorbent which has adsorbed various ions in the brine is separated from the brine, the adsorbent is remained on the filter cloth 2, and the brine passes through the filter cloth 2 and enters the corresponding liquid collection cavity 42.
As shown in fig. 1, a brine recovery port 43 is formed at the bottom of each liquid collection cavity 42 corresponding to the solid-liquid separation zone 100, each brine recovery port 43 is connected to a brine filtering barrel 44 through a pipeline, the brine filtering barrel 44 is connected to a vacuum pumping mechanism (such as a vacuum pump, not shown in the figure), brine can rapidly pass through the filter cloth 2 to enter the liquid collection cavity 42 and the brine filtering barrel 44 under the action of the vacuum pumping mechanism, and the adsorbent can form a filter cake with a thickness of about 1.5-4 cm on the filter cloth 2.
As can be seen from fig. 1, in order to ensure sufficient collection of brine, the discharge end of the mixed adsorption mechanism 5 is located at the initial end of the solid-liquid separation zone 100 (i.e. the end away from the salt-washing zone 200), so as to ensure that all brine enters the liquid collection chamber 42 corresponding to the solid-liquid separation zone 100 and does not enter the downstream salt-washing zone 200.
Since the adsorbent used in this embodiment is a powdered adsorbent (aluminum adsorbent with a particle size of 75 μm), it is difficult for the filter cloth 2 to completely block the adsorbent, and the collected brine contains more or less adsorbents. Therefore, the present embodiment further provides an adsorbent recovery mechanism 10 connected to the brine leaching tank 44, and the adsorbent recovery mechanism 10 may adopt a magnetic separator 101, a precision filter, a ceramic membrane, and other screening devices, so as to separate the adsorbent from the collected brine, and then return the brine to the salt pan or the salt lake.
As shown in fig. 1, in the salt-washing zone 200, a salt-washing liquid conveying mechanism 6 is disposed above the filter cloth 2, and the salt-washing liquid conveying mechanism 6 is used for applying a salt-washing liquid to the filter cake entering the salt-washing zone 200 along with the filter cloth 2. The salt washing solution used in this embodiment may be fresh water or other solution with low salinity. The salt washing liquid conveying mechanism 6 adopts liquid conveying equipment commonly used in the prior art, and only needs to ensure uniform transfusion in the vertical direction, and can comprise a salt washing liquid conveying pipe 61 connected with a salt washing liquid storage tank (not shown in the figure), wherein a salt washing liquid conveying pump (not shown in the figure) is installed on the salt washing liquid conveying pipe 61, a water distribution disc (not shown in the figure) can be installed at the liquid outlet end of the salt washing liquid conveying pipe 61, the water distribution diameter of the water distribution disc is equivalent to the width of a filter cake, and the salt washing effect is ensured.
Similarly, the bottom of each liquid collecting cavity 42 corresponding to the salt washing area 200 is provided with a salt eluent collecting port 45, each salt eluent collecting port 45 is connected with a salt eluent pumping barrel 46 through a pipeline, the salt eluent pumping barrel 46 is connected with a vacuum pumping mechanism (such as a vacuum pump), under the action of the vacuum pumping mechanism, the salt washing liquid can rapidly penetrate through the filter cake, and the contact time of the salt washing liquid and the filter cake is controlled within 10 seconds (preferably 1-2 seconds).
Likewise, to ensure adequate collection of the salt eluate, the outlet end of the salt eluate delivery mechanism 6 is at the beginning of the salt elution zone 200 (i.e., the end proximate the solid-liquid separation zone 100), ensuring that all of the salt eluate enters the liquid collection chamber 42 corresponding to the salt elution zone 200 and not the downstream desorption zone 300.
According to the research of the applicant, as the brine is a high-salt even salt saturated solution, when the brine is mixed with the adsorbent, various salt ions including lithium ions can be adsorbed on the adsorbent; however, the adsorption mechanism of lithium ions is different from that of other salt ions, lithium ions are squeezed into the crystal lattice of the amorphous hydroxide adsorbent by the salt in the brine to form a molecular sieve, and other salt ions cannot enter the crystal lattice of the amorphous hydroxide adsorbent, so that the bonding strength between the lithium ions and the adsorbent is different from that between the lithium ions and the adsorbent. Because the combination of salt ions and the adsorbent is weak, in the salt washing area 200, the filter cake is quickly washed by the salt washing liquid in a short time, so that the salt ions can be taken away to the maximum extent, the lithium ions can be taken away to the minimum extent, and the purpose of 'throwing salt and leaving lithium' is achieved.
The collected salt eluent also contains an adsorbent, so the embodiment is also provided with an adsorbent recovery mechanism 10 connected with the salt eluent suction barrel 46, and the adsorbent recovery mechanism 10 can adopt a magnetic separator 101, a precision filter, a ceramic membrane and other screening equipment so as to separate the adsorbent from the collected salt eluent, and then send the salt eluent to a salt lake or a salt pan or be used in other processes.
As shown in fig. 1, a desorption liquid delivery mechanism 7 is disposed above the filter cloth 2 in the desorption zone 300, and the desorption liquid delivery mechanism 7 is used for delivering a desorption liquid to the filter cake entering the desorption zone 300 along with the filter cloth 2, wherein the desorption liquid used in the present embodiment may be fresh water or other solution with lower salinity. The desorption liquid conveying mechanism 7 may be a liquid conveying device commonly used in the art as long as uniform liquid conveyance in the vertical direction is ensured, and may be of the same structure as the aforementioned wash salt liquid conveying mechanism 6.
Similarly, the bottom of each liquid collecting cavity 42 corresponding to the desorption area 300 is provided with a lithium eluent collecting port 47, each lithium eluent collecting port 47 is connected with a lithium eluent pumping barrel 48 through a pipeline, the lithium eluent pumping barrel 48 is connected with a vacuum pumping mechanism (such as a vacuum pump), and the desorption liquid can rapidly pass through the filter cake under the action of the vacuum pumping mechanism, so that the contact time of the desorption liquid and the filter cake is controlled within 10 seconds, preferably 1-2 seconds.
Likewise, to ensure sufficient collection of the lithium eluate, the liquid outlet end of the desorption liquid delivery mechanism 7 is located at the beginning of the desorption region 300 (i.e., the end near the salt elution region 200), ensuring that all the lithium desorption liquid enters the liquid collection chamber 42 corresponding to the desorption region 300.
After the ions except lithium on the adsorbent are pre-eluted through the salt eluting region 200, the salt-lithium ratio on the adsorbent is greatly reduced, and at the moment, the lithium ions on the adsorbent are eluted by desorption liquid, so that lithium eluent with higher lithium concentration can be obtained.
Similarly, the collected lithium eluate also contains an adsorbent, and therefore, in this embodiment, an adsorbent recovery mechanism 10 connected to the lithium eluate suction/filtration tank 48 is also provided, and the adsorbent recovery mechanism 10 may employ a magnetic separator 101, a precision filter, a ceramic membrane, or other screening equipment to separate the adsorbent from the collected lithium eluate, and then send the lithium eluate to the next purification step.
At the end point of the filter cloth advancing direction, the desorbed adsorbent is collected by the adsorbent recovery mechanism 8 and sent to the mixed adsorption mechanism 5 for recycling.
The application method of the belt filter in the adsorption method for extracting lithium from brine comprises the following steps:
(1) uniformly mixing the adsorbent and brine in a mixed adsorption mechanism 5;
feeding the adsorbent and the brine into a mixing tank 51 in proportion, starting a stirring assembly, uniformly stirring the adsorbent and the brine, and adsorbing various ions in the brine by the adsorbent in the stirring process; when the production line is initially started, the adsorbent and brine are stirred in the mixing tank 51 for a period of time (about several minutes) and then discharged, so as to ensure effective adsorption of the adsorbent; after the production line begins to operate, the adsorbent and the brine can be continuously fed, and the adsorbent and brine mixture can also be continuously discharged.
(2) Conveying the adsorbent brine mixture to a solid-liquid separation zone 100 to separate the adsorbent from the brine and make the adsorbent into a filter cake on a filter cloth 2;
after the adsorbent is adsorbed, discharging the adsorbent brine mixture from the mixing tank 51, wherein the discharge end of the mixing tank 51 is positioned at the starting end of the solid-liquid separation zone 100, the adsorbent brine mixture discharged from the mixing tank 51 gradually falls on the running filter cloth 2, and under the assistance of a vacuumizing mechanism, the brine passes through the filter cloth 2 and enters the corresponding liquid collection cavity 42, and is collected into a brine leaching barrel 44 through each brine recovery port 43; the recovered brine can be returned to a salt lake or a salt pan after being recovered by the adsorbent;
on the filter cloth 2 running at a constant speed, the adsorbent discharged at a constant speed forms a filter cake with the thickness of about 1.5-4 cm under the action of a vacuum pumping mechanism; due to the continuous discharge, the filter cake extends over the entire travel of the filter cloth 2.
(3) The filter cake goes to a salt washing area 200 along with the filter cloth 2, in the salt washing area 200, a salt washing liquid conveying mechanism 6 conveys the salt washing liquid to the filter cake, so that ions adsorbed on the filter cake except lithium are eluted, and a salt eluent is collected;
the salt washing liquid is applied to the filter cake from the starting end of the salt washing area 200, and only needs 1-2 seconds for the salt washing liquid to pass through the filter cake with the assistance of a vacuumizing mechanism, and the salt is thrown and lithium is left as far as possible;
the collected salt eluent is recycled by an adsorbent and can be sent to a salt lake or a salt pan or used in other processes;
(4) the filter cake goes to the desorption area 300 along with the filter cloth 2, and in the desorption area 300, a desorption liquid conveying mechanism 7 conveys desorption liquid to the filter cake to enable lithium ions adsorbed on the filter cake to be eluted, and lithium eluent is collected;
the desorption liquid is distributed to the filter cloth 2 from the starting end of the desorption area 300, and passes through the filter cake with the assistance of the vacuum pumping mechanism, so that lithium is eluted from the adsorbent; the collected lithium eluent is sent to a downstream process for refining and purification after being subjected to adsorbent recovery;
(5) at the end point of the advancing direction of the filter cloth 2, the desorbed adsorbent is conveyed to the mixed adsorption mechanism 5, and the adsorbent recovered by the adsorbent recovery mechanism 10 can also be returned to the mixed adsorption mechanism 5, so that a new cycle of lithium extraction from the adsorption brine is performed.
In the lithium eluate obtained by using the belt filter of the embodiment, the salt-lithium ratio is less than 10:1, the magnesium-lithium ratio is less than 1:1, and the lithium concentration is about 0.4 g/l; the dosage of the salt washing liquid is 30 percent of the amount of brine, and the lithium recovery rate is 70 percent.
Example 2
As shown in fig. 2, the belt filter of the present embodiment is substantially the same as that of embodiment 1, except that: along the advancing direction of the filter cloth 2, a solid-liquid separation area 100, a salt washing area 200, a desorption area 300 and a salt washing water return area 400 are formed on the frame 1, namely the salt washing water return area 400 is also arranged at the downstream of the desorption area 300; a salt eluent backflow mechanism 9 is arranged above the salt washing water return area 400, and the liquid inlet end of the salt eluent backflow mechanism 9 is connected with the salt eluent suction-filtration barrel 46, so that the salt eluent is adsorbed again by the adsorbents which pass through the salt washing area 200 and the desorption area 300.
The applicant researches and discovers that the adsorbent can rapidly trap lithium ions in a high-salt-concentration solution, and the adsorption equilibrium of the adsorbent can be reached to more than 60% within tens of seconds of contact time. Therefore, the adsorbent which finishes salt washing and desorption adsorbs the salt eluent with higher salt concentration in advance and then is sent back to the mixed adsorption mechanism 5, so that after the part of the adsorbent enters the mixing tank 51, lithium ions in the raw material brine can be rapidly trapped, thereby realizing continuous feeding of the adsorbent and the raw material brine and continuous discharging of the adsorbent brine mixture and realizing continuous production; in addition, lithium ions in the salt eluent can be recovered, and the lithium recovery rate is further improved.
Similarly, the salt washing water return area 400 is also correspondingly provided with a plurality of liquid collecting cavities 42 for collecting the re-adsorption filtrate passing through the filter cake and the filter cloth 2; the bottom of each liquid collecting cavity 42 is also provided with a re-adsorption filtrate collecting port 49, the re-adsorption filtrate collecting port 49 is connected with a re-adsorption filtrate suction and filtration barrel 410 through a pipeline, and the re-adsorption filtrate suction and filtration barrel 410 is connected with a vacuum pumping mechanism. Before the filtrate in the filtrate suction drum 410 enters the downstream treatment process, the adsorbent in the filtrate needs to be recovered by an adsorbent recovery mechanism 10 such as a magnetic separator 101.
The application method of the belt filter in the adsorption method for extracting lithium from brine comprises the following steps:
(1) uniformly mixing the adsorbent and brine in a mixed adsorption mechanism 5;
feeding the adsorbent and the brine into a mixing tank 51 in proportion, starting a stirring assembly, uniformly stirring the adsorbent and the brine, and adsorbing various ions in the brine by the adsorbent in the stirring process; when the production line is initially started, the adsorbent and brine are required to be stirred in the mixing tank 51 for a period of time of about several minutes and then discharged, so as to ensure effective adsorption of the adsorbent; after the production line begins to operate, the adsorbent and the brine can be continuously fed, and the adsorbent and brine mixture can also be continuously discharged.
(2) Conveying the adsorbent brine mixture to a solid-liquid separation zone 100 to separate the adsorbent from the brine and make the adsorbent into a filter cake on a filter cloth 2;
after the adsorbent is adsorbed, discharging the adsorbent brine mixture from the mixing tank 51, wherein the discharge end of the mixing tank 51 is positioned at the starting end of the solid-liquid separation zone 100, the adsorbent brine mixture discharged from the mixing tank 51 gradually falls on the running filter cloth 2, and under the assistance of a vacuumizing mechanism, the brine passes through the filter cloth 2 and enters the corresponding liquid collection cavity 42, and is collected into a brine leaching barrel 44 through each brine recovery port 43; the recovered brine can be returned to a salt lake or a salt pan after being recovered by the adsorbent;
on the filter cloth 2 running at a constant speed, the adsorbent discharged at a constant speed forms a filter cake with the thickness of about 1.5-4 cm under the action of a vacuum pumping mechanism; due to the continuous discharge, the filter cake extends over the entire travel of the filter cloth 2.
(3) The filter cake goes to a salt washing area 200 along with the filter cloth 2, in the salt washing area 200, a salt washing liquid conveying mechanism 6 conveys the salt washing liquid to the filter cake, so that ions adsorbed on the filter cake except lithium are eluted, and a salt eluent is collected;
the salt washing liquid is applied to the filter cake from the starting end of the salt washing area 200, and only needs 1-2 seconds for the salt washing liquid to pass through the filter cake with the assistance of a vacuumizing mechanism, and the salt is thrown and lithium is left as far as possible;
(4) the filter cake goes to the desorption area 300 along with the filter cloth 2, and in the desorption area 300, a desorption liquid conveying mechanism 7 conveys desorption liquid to the filter cake to enable lithium ions adsorbed on the filter cake to be eluted, and lithium eluent is collected;
the desorption liquid is distributed to the filter cloth 2 from the starting end of the desorption area 300, and passes through the filter cake with the assistance of the vacuum pumping mechanism, so that lithium is eluted from the adsorbent; the collected lithium eluent is sent to a downstream process for refining and purification after being subjected to adsorbent recovery;
(5) conveying the salt eluent collected in the step 3 to a salt washing water return area 400 to pre-adsorb the adsorbent; the collected re-adsorption filtrate is sent to a salt pan or a salt lake after being recovered by an adsorbent;
(6) at the end point of the advancing direction of the filter cloth 2, the adsorbent recovery mechanism 8 collects the pre-adsorbed adsorbent and conveys the pre-adsorbed adsorbent to the mixed adsorption mechanism 5, and the adsorbent recovered by the adsorbent recovery mechanism 10 is also conveyed back to the mixed adsorption mechanism 5 to perform a new cycle of lithium extraction from the adsorption brine.
In the lithium eluate obtained by using the belt filter of the embodiment, the salt-lithium ratio is less than 10:1, the magnesium-lithium ratio is less than 1:1, and the lithium concentration is about 0.4 g/l; the dosage of the salt washing liquid is 30% of the brine amount, and the lithium recovery rate reaches 80%.
Example 3
As shown in fig. 3, the main structure of the belt filter of the present embodiment is the same as that of embodiment 1 or embodiment 2, except that: the salt-washing liquid conveying mechanism 6 of the salt-washing area 200 has at least two liquid outlet ends (three are provided in the embodiment), and all the liquid outlet ends are uniformly arranged along the advancing direction of the filter cloth 2.
The specific mode of arranging the three liquid outlet ends can be as follows: three salt washing liquid conveying pipes 61 are arranged, the three salt washing liquid conveying pipes 61 are connected with a salt washing liquid storage tank through a four-way valve, a water distribution disc is mounted at the liquid outlet end of each salt washing liquid conveying pipe 61, the water distribution diameter of each water distribution disc is equivalent to the width of a filter cake, and the salt washing effect is ensured.
When the salt washing liquid is conveyed, one salt washing liquid conveying pump is adopted to provide power for three salt washing liquid conveying pipes 61 at the same time, or one salt washing liquid conveying pump is arranged on each salt washing liquid conveying pipe 61, and the method and the device can be implemented.
Similarly, the outlet ends of the salt-washing liquid conveying mechanism 6 are uniformly arranged with the starting end of the salt-washing area 200 as the starting point, so as to ensure that the last outlet end is slightly far away from the tail end of the salt-washing area 200, so as to reserve a certain time for the salt-washing liquid filtering cake, and ensure that the salt eluent does not enter the desorption area 300.
Compared with the embodiment 1 with only one liquid outlet end, the total amount of the salt washing liquid used by a plurality of liquid outlet ends is unchanged, but the salt washing efficiency is higher because the salt washing is realized by 'washing for a plurality of times with small dosage'.
In the lithium eluate obtained by using the belt filter of the embodiment, the salt-lithium ratio is less than 10:1, the magnesium-lithium ratio is less than 1:1, and the lithium concentration is about 0.4 g/l; the dosage of the salt washing liquid is 23 percent of the amount of brine, and the recovery rate of lithium reaches 85 percent.
Example 4
As shown in fig. 3, the main structure of the belt filter of the present embodiment is the same as that of embodiment 1, embodiment 2 or embodiment 3, except that: the desorption liquid conveying mechanism 7 of the desorption zone 300 has at least two liquid outlet ends (three are provided in this embodiment), and all the liquid outlet ends are uniformly arranged along the advancing direction of the filter cloth 2.
The desorption liquid conveying mechanism 7 with a plurality of liquid outlet ends can be arranged in the same way as the salt washing liquid conveying mechanism 6 in the embodiment 3, and a plurality of desorption liquid conveying pipes 71 are also arranged.
Compared with the case of only one liquid outlet end in the embodiment 1, the total amount of the desorption liquid used by a plurality of liquid outlet ends is unchanged, but the desorption efficiency is higher because the small-dose multiple washing is realized during desorption, and the lithium recovery rate can be further improved.
In the lithium eluate obtained by the belt filter of the embodiment, the salt-lithium ratio is less than 10:1, the magnesium-lithium ratio is less than 1:1, and the lithium concentration reaches 0.45 g/l; the dosage of the salt washing liquid is 23 percent of the amount of brine, and the recovery rate of lithium reaches 85 percent.
Example 5
As shown in fig. 4, the main structure of the belt filter of this embodiment is the same as that of embodiment 1, embodiment 2 or embodiment 4, except that: the salt washing liquid conveying mechanism 6 of the salt washing area 200 is provided with at least two liquid outlet ends (three are provided in the embodiment), and all the liquid outlet ends are uniformly arranged along the advancing direction of the filter cloth 2; in addition, the salt concentration of the salt washing solution conveyed by each liquid outlet end is gradually increased along the direction opposite to the advancing direction of the filter cloth 2.
The specific setting mode of the salt washing liquid conveying mechanism 6 can be as follows: the salt washing liquid conveying mechanism 6 comprises two salt washing liquid primary supply assemblies 62 and at least one salt washing liquid circulating assembly 63, and the salt washing liquid primary supply assemblies 62 and the salt washing liquid circulating assemblies 63 are sequentially connected in series along the opposite direction of the advancing direction of the filter cloth 2.
In this embodiment, the structures of the salt-washing liquid primary supply assembly 62 and the salt-washing liquid circulation assembly 63 are the same, and the structures of the salt-washing liquid primary supply assembly 62 and the salt-washing liquid circulation assembly 63 may be the same as those of the salt-washing liquid conveying mechanism 6 in embodiment 1, the liquid outlet ends of the salt-washing liquid primary supply assembly 62 and the salt-washing liquid circulation assembly 63 are both located above the salt-washing area 200, and the salt-washing liquid suction-filtration barrels 46 corresponding to the liquid outlet ends are arranged below the salt-washing area 200; however, the positions of the liquid inlet ends of the salt washing liquid primary supply assembly 62 and the salt washing liquid circulation assembly 63 are connected correspondingly are different, wherein the liquid inlet end of the salt washing liquid primary supply assembly 62 is connected with the salt washing liquid storage tank, and the liquid inlet end of the salt washing liquid circulation assembly 63 is connected with the salt eluent suction-filtration barrel 46 corresponding to the salt washing liquid primary supply assembly 62, or is connected with the salt eluent suction-filtration barrel 46 corresponding to the last salt washing liquid circulation assembly 63.
The supply of the salt washing liquid is carried out along the reverse direction of the advancing direction of the filter cloth 2, the salt washing liquid of the salt washing liquid circulating assembly 63 is collected from the salt washing liquid suction and filtration barrel 46 of the salt washing liquid primary supply assembly 62 or the previous salt washing liquid circulating assembly 63, and the salt washing liquid passes through at least one time, so the salt concentration of the salt washing liquid at the liquid outlet end of the salt washing liquid circulating assembly 63 is always higher than that of the salt washing liquid primary supply assembly 62 or the previous salt washing liquid circulating assembly 63, and the concentration gradient reverse elution of the salt washing liquid is realized.
The applicant researches and discovers that the adsorbent trapping lithium ions still has lithium ion loss in the salt washing process, but the higher the salt concentration of the salt washing solution, the lower the lithium ion loss rate. Therefore, the present embodiment provides the above-mentioned reverse elution manner with a concentration gradient of the salt-washing solution, so as to reduce the loss of lithium ions on the adsorbent during the salt-washing process as much as possible.
Similarly, in this embodiment, the outlet ends of the salt-washing liquid conveying mechanism 6 are uniformly arranged with the starting end of the salt-washing area 200 as the starting point, so as to ensure that the last outlet end is slightly far away from the tail end of the salt-washing area 200, so as to reserve a certain time for the salt-washing liquid filtering cake, and ensure that the salt eluent does not enter the desorption area 300.
In the lithium eluate obtained by the belt filter of the embodiment, the salt-lithium ratio is less than 10:1, the magnesium-lithium ratio is less than 1:1, and the lithium concentration reaches 0.45 g/l; the dosage of the salt washing liquid is 17 percent of the amount of the brine, and the recovery rate of the lithium is close to 90 percent.
Example 6
As shown in fig. 4, the main body structure of the belt filter of the present embodiment is the same as that of embodiment 1, embodiment 2, embodiment 3 or embodiment 5, except that: the desorption liquid conveying mechanism 7 of the desorption area 300 is provided with at least two liquid outlet ends (three liquid outlet ends are provided in the embodiment), and all the liquid outlet ends are uniformly arranged along the advancing direction of the filter cloth 2; the desorption liquid conveying mechanism 7 comprises a desorption liquid initial supply component 72 and at least one desorption liquid circulation component 73, wherein the desorption liquid initial supply component 72 and the desorption liquid circulation component 73 are sequentially connected in series along the direction opposite to the advancing direction of the filter cloth 2.
In this embodiment, the structure of the desorption liquid conveying mechanism 7 is the same as that of the wash salt liquid conveying mechanism 6 in embodiment 5.
In the lithium eluate obtained by the belt filter of the embodiment, the salt-lithium ratio is less than 10:1, the magnesium-lithium ratio is less than 1:1, and the lithium concentration reaches 0.5 g/l; the dosage of the salt washing liquid is 17 percent of the amount of the brine, and the recovery rate of the lithium is close to 90 percent.
Claims (10)
1. The utility model provides a belt filter, includes frame (1), frame (1) on be equipped with filter cloth (2) of reciprocal gyration operation, its characterized in that is equipped with in proper order along filter cloth (2) advancing direction:
a mixed adsorption mechanism (5) for conveying an adsorbent brine mixture to the solid-liquid separation zone (100) is arranged above the filter cloth (2);
a salt washing liquid conveying mechanism (6) for conveying the salt washing liquid to the salt washing area (200) is distributed above the filter cloth (2);
the device comprises a desorption area (300), wherein a desorption liquid conveying mechanism (7) for conveying desorption liquid to the desorption area (300) is distributed above the filter cloth (2), and a lithium eluent collecting port (47) is arranged below the desorption area (300).
2. The belt filter of claim 1, wherein a brine recovery port (43) is arranged below the solid-liquid separation zone (100), a salt eluent collecting port (45) is arranged below the salt washing zone (200), and at least one of the brine recovery port (43), the salt eluent collecting port (45) and the lithium eluent collecting port (47) is connected with a vacuum pumping mechanism;
at least one of the brine recovery port (43), the salt eluent collection port (45) and the lithium eluent collection port (47) is connected with an adsorbent recovery mechanism (10).
3. A belt filter as in claim 1, wherein the wash salt solution conveyor means (6) have at least two outlet ends arranged in the forward direction of the filter cloth (2).
4. A belt filter as in claim 3, characterized in that said outlet end delivers a washing salt solution with a gradually higher salt concentration in the direction opposite to the forward direction of the filter cloth (2).
5. A belt filter as in claim 4, wherein the washing salt solution delivery mechanism (6) comprises a washing salt solution pre-feeding assembly (62) and at least one washing salt solution circulating assembly (63), the washing salt solution pre-feeding assembly (62) and the washing salt solution circulating assembly (63) being connected in series in sequence along a direction opposite to the advancing direction of the filter cloth (2);
the liquid outlet ends of the salt washing liquid primary supply assembly (62) and the salt washing liquid circulating assembly (63) are located above the salt washing area (200), salt washing liquid collecting ports (45) corresponding to the liquid outlet ends are arranged below the salt washing area (200), the liquid inlet end of the salt washing liquid primary supply assembly (62) is connected with a salt washing liquid storage tank, and the liquid inlet end of the salt washing liquid circulating assembly (63) is connected with the salt washing liquid primary supply assembly (62) or the salt washing liquid collecting port (45) corresponding to the last salt washing liquid circulating assembly (63).
6. The belt filter as claimed in claim 1, characterized in that the stripping liquid feed (7) has at least two outlet ends arranged in the direction of advance of the filter cloth (2).
7. The belt filter according to claim 6, wherein the desorption liquid conveying mechanism (7) comprises a desorption liquid initial supply assembly (72) and at least one desorption liquid circulation assembly (73), the desorption liquid initial supply assembly (72) and the desorption liquid circulation assembly (73) are connected in series in sequence along the direction opposite to the advancing direction of the filter cloth (2);
the liquid outlet ends of the desorption liquid initial supply assembly (72) and the desorption liquid circulation assembly (73) are both positioned above the desorption area (300), lithium eluent collecting ports (47) corresponding to the liquid outlet ends are arranged below the desorption area (300), the liquid inlet end of the desorption liquid initial supply assembly (72) is connected with a desorption liquid storage tank, and the liquid inlet end of the desorption liquid circulation assembly (73) is connected with the lithium eluent collecting port (47) corresponding to the desorption liquid initial supply assembly (72) or the previous desorption liquid circulation assembly (73).
8. The belt filter according to any one of claims 1 to 7, characterized in that a salt washing water return zone (400) is further arranged at the downstream of the desorption zone (300), a salt eluent return mechanism (9) is arranged above the salt washing water return zone (400), and the liquid inlet end of the salt eluent return mechanism (9) is connected with the salt eluent collecting port (45);
an adsorbent recovery mechanism (8) is arranged at the downstream of the salt washing water return area (400), and the adsorbent recovery mechanism (8) is connected with the mixed adsorption mechanism (5).
9. Use of a belt filter according to any one of claims 1 to 7 for extracting lithium from adsorption brine, comprising:
(1) uniformly mixing an adsorbent and brine in the mixed adsorption mechanism (5);
(2) conveying the adsorbent brine mixture to a solid-liquid separation zone (100), separating the adsorbent from brine and preparing the adsorbent into a filter cake on filter cloth (2);
(3) the filter cake goes to a salt washing area (200) along with the filter cloth (2), in the salt washing area (200), the salt washing liquid conveying mechanism (6) conveys the salt washing liquid to the filter cake, so that ions adsorbed on the filter cake except lithium are eluted, and salt eluent is collected;
(4) the filter cake goes to a desorption area (300) along with the filter cloth (2), and in the desorption area (300), the desorption liquid conveying mechanism (7) conveys desorption liquid to the filter cake, so that lithium ions adsorbed on the filter cake are eluted, and lithium eluent is collected;
(5) and at the end point of the advancing direction of the filter cloth (2), collecting the desorbed adsorbent and conveying the adsorbent to a mixed adsorption mechanism (5) for carrying out a new cycle of lithium extraction from the adsorption brine.
10. The use of the belt filter of claim 8 for extracting lithium from adsorption brine, comprising:
(1) uniformly mixing an adsorbent and brine in the mixed adsorption mechanism (5);
(2) conveying the adsorbent brine mixture to a solid-liquid separation zone (100), separating the adsorbent from brine and preparing the adsorbent into a filter cake on filter cloth (2);
(3) the filter cake goes to a salt washing area (200) along with the filter cloth (2), in the salt washing area (200), the salt washing liquid conveying mechanism (6) conveys the salt washing liquid to the filter cake, so that ions adsorbed on the filter cake except lithium are eluted, and salt eluent is collected;
(4) the filter cake goes to a desorption area (300) along with the filter cloth (2), and in the desorption area (300), the desorption liquid conveying mechanism (7) conveys desorption liquid to the filter cake, so that lithium ions adsorbed on the filter cake are eluted, and lithium eluent is collected;
(5) conveying the salt eluent collected in the step (3) to a salt washing water return area (400) to pre-adsorb the adsorbent;
(6) and collecting the pre-adsorbed adsorbent at the end point of the advancing direction of the filter cloth (2), conveying the adsorbent to a mixed adsorption mechanism (5), and performing a new cycle of lithium extraction from the adsorption brine.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010646187.8A CN111825152B (en) | 2020-07-07 | 2020-07-07 | Belt filter and application thereof in adsorption method brine lithium extraction |
| PCT/CN2021/103006 WO2022007662A1 (en) | 2020-07-07 | 2021-06-29 | Band filter and application thereof in extraction of lithium from brine using adsorption method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010646187.8A CN111825152B (en) | 2020-07-07 | 2020-07-07 | Belt filter and application thereof in adsorption method brine lithium extraction |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111825152A true CN111825152A (en) | 2020-10-27 |
| CN111825152B CN111825152B (en) | 2022-11-01 |
Family
ID=72900306
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010646187.8A Active CN111825152B (en) | 2020-07-07 | 2020-07-07 | Belt filter and application thereof in adsorption method brine lithium extraction |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN111825152B (en) |
| WO (1) | WO2022007662A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113088695A (en) * | 2021-03-12 | 2021-07-09 | 华东理工大学 | Gradient simulated moving bed method for large-scale combined extraction of boron and lithium in brine |
| WO2022007662A1 (en) * | 2020-07-07 | 2022-01-13 | 浙江衢州明德新材料有限公司 | Band filter and application thereof in extraction of lithium from brine using adsorption method |
| WO2022007811A1 (en) * | 2020-07-07 | 2022-01-13 | 浙江衢州明德新材料有限公司 | Device for extracting lithium from brine by using adsorption method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101012072A (en) * | 2006-12-31 | 2007-08-08 | 于向真 | Adsorption treatment process for sewage |
| CN104310446A (en) * | 2014-10-17 | 2015-01-28 | 江苏久吾高科技股份有限公司 | Process and device for extracting battery grade lithium from brine |
| US20180280831A1 (en) * | 2017-03-31 | 2018-10-04 | Korea Institute Of Geoscience And Mineral Resources | Onshore lithium-recovering apparatus for lithium ion adsorption and desorption process and lithium-recovering method using the same |
| CN209123481U (en) * | 2018-08-30 | 2019-07-19 | 成都泰利创富锂业科技有限公司 | A kind of continuous adsorption-desorption system mentioning lithium for industry |
| CN210583956U (en) * | 2019-08-20 | 2020-05-22 | 白银扎布耶锂业有限公司 | A vacuum belt filter washes edulcoration device for lithium ore pulp |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6207126B1 (en) * | 1998-07-16 | 2001-03-27 | Chemetall Foote Corporation | Recovery of lithium compounds from brines |
| US7157065B2 (en) * | 1998-07-16 | 2007-01-02 | Chemetall Foote Corporation | Production of lithium compounds directly from lithium containing brines |
| CN109650413B (en) * | 2018-12-07 | 2021-05-25 | 三门峡联利新材料有限公司 | Method and system for enriching lithium from sodium aluminate solution in alumina plant |
| CN213221252U (en) * | 2020-07-07 | 2021-05-18 | 浙江衢州明德新材料有限公司 | Salt lithium separation device applied to brine lithium extraction process |
| CN213221207U (en) * | 2020-07-07 | 2021-05-18 | 浙江衢州明德新材料有限公司 | Adsorbent recovery device applied to brine lithium extraction equipment |
| CN111825152B (en) * | 2020-07-07 | 2022-11-01 | 西宁永正锂业有限公司 | Belt filter and application thereof in adsorption method brine lithium extraction |
| CN213221206U (en) * | 2020-07-07 | 2021-05-18 | 浙江衢州明德新材料有限公司 | Salt-washing backwater structure for lithium extraction device |
| CN212700660U (en) * | 2020-07-07 | 2021-03-16 | 浙江衢州明德新材料有限公司 | Equipment for extracting lithium from brine by adsorption method |
| CN111729350B (en) * | 2020-07-07 | 2023-09-08 | 衢州永正锂业科技有限公司 | Equipment for extracting lithium from brine by adsorption method |
| CN111826531A (en) * | 2020-07-07 | 2020-10-27 | 浙江衢州明德新材料有限公司 | Method for extracting lithium from brine by using powdery adsorbent |
| CN213221229U (en) * | 2020-07-07 | 2021-05-18 | 浙江衢州明德新材料有限公司 | Water distribution structure of belt filter for extracting lithium from brine |
-
2020
- 2020-07-07 CN CN202010646187.8A patent/CN111825152B/en active Active
-
2021
- 2021-06-29 WO PCT/CN2021/103006 patent/WO2022007662A1/en active Application Filing
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101012072A (en) * | 2006-12-31 | 2007-08-08 | 于向真 | Adsorption treatment process for sewage |
| CN104310446A (en) * | 2014-10-17 | 2015-01-28 | 江苏久吾高科技股份有限公司 | Process and device for extracting battery grade lithium from brine |
| US20180280831A1 (en) * | 2017-03-31 | 2018-10-04 | Korea Institute Of Geoscience And Mineral Resources | Onshore lithium-recovering apparatus for lithium ion adsorption and desorption process and lithium-recovering method using the same |
| CN209123481U (en) * | 2018-08-30 | 2019-07-19 | 成都泰利创富锂业科技有限公司 | A kind of continuous adsorption-desorption system mentioning lithium for industry |
| CN210583956U (en) * | 2019-08-20 | 2020-05-22 | 白银扎布耶锂业有限公司 | A vacuum belt filter washes edulcoration device for lithium ore pulp |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022007662A1 (en) * | 2020-07-07 | 2022-01-13 | 浙江衢州明德新材料有限公司 | Band filter and application thereof in extraction of lithium from brine using adsorption method |
| WO2022007811A1 (en) * | 2020-07-07 | 2022-01-13 | 浙江衢州明德新材料有限公司 | Device for extracting lithium from brine by using adsorption method |
| CN113088695A (en) * | 2021-03-12 | 2021-07-09 | 华东理工大学 | Gradient simulated moving bed method for large-scale combined extraction of boron and lithium in brine |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2022007662A1 (en) | 2022-01-13 |
| CN111825152B (en) | 2022-11-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111825152B (en) | Belt filter and application thereof in adsorption method brine lithium extraction | |
| CN213221252U (en) | Salt lithium separation device applied to brine lithium extraction process | |
| CN111729350B (en) | Equipment for extracting lithium from brine by adsorption method | |
| CN104310446B (en) | A kind of technique and device being extracted battery grade lithium by salt | |
| CN111826531A (en) | Method for extracting lithium from brine by using powdery adsorbent | |
| CN109354043A (en) | Clean the method for mentioning lithium from super low concentration brine containing lithium | |
| CN213221207U (en) | Adsorbent recovery device applied to brine lithium extraction equipment | |
| CN212700660U (en) | Equipment for extracting lithium from brine by adsorption method | |
| CN213221206U (en) | Salt-washing backwater structure for lithium extraction device | |
| CN107585982B (en) | Recovery and reducing sugar conversion treatment device and method for proteins and phosphorus in municipal domestic sludge | |
| CN113666396A (en) | Ion rectification method for preparing lithium chloride from salt lake brine | |
| CN111961856B (en) | Device for separating vanadium and rare earth elements from waste FCC catalyst | |
| RU2490344C1 (en) | Extraction method of gold from ores and products of their processing | |
| CN204447403U (en) | A kind of active carbon continuous flow upstream adsorptive purifier | |
| CN207126648U (en) | A kind of charcoal water wash system | |
| CN101508656B (en) | Ion-exchange recovery method for synergistic matter in Bt fermentation | |
| CN115595455B (en) | System and method for extracting lithium from low-grade brine and application | |
| CN113663518B (en) | Ion cooperative distillation system for fine screening of special mixed ions and application thereof | |
| CN211226764U (en) | Retrieve device of copper in follow copper-containing waste liquid | |
| CN114752785A (en) | Application of inorganic adsorbent and continuous fluid separation combined process technology in lithium extraction from brine | |
| CN110790441A (en) | Device and method for recovering copper from copper-containing waste liquid | |
| CN207512005U (en) | The processing system of ball-shape nickel hydroxide production process waste water | |
| CN215480101U (en) | Ion cyaniding gold extraction tail liquid adsorption and deposition device | |
| CN208661658U (en) | A kind of active carbon sorting device | |
| CN210237284U (en) | Device for recovering and purifying organic phase from copper extraction interphase dirt |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| TA01 | Transfer of patent application right | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20220923 Address after: 810000 room 1013, building 1, No. 457, Qiyi Road, Chengzhong District, Xining City, Qinghai Province Applicant after: Xining Yongzheng Lithium Industry Co.,Ltd. Address before: 324000 4th floor, No.23 Huayang Road, Kaihua County, Quzhou City, Zhejiang Province (self declaration) Applicant before: Zhejiang Quzhou Mingde New Material Co.,Ltd. |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address | ||
| CP03 | Change of name, title or address |
Address after: Room 101, No. 15 Chuncheng Road, Quzhou City, Zhejiang Province, 324012 Patentee after: Quzhou Yongzheng Lithium Industry Technology Co.,Ltd. Address before: 810000 room 1013, building 1, No. 457, Qiyi Road, Chengzhong District, Xining City, Qinghai Province Patentee before: Xining Yongzheng Lithium Industry Co.,Ltd. |