CN217757168U - Nanofiltration water purification system for high-salinity wastewater - Google Patents
Nanofiltration water purification system for high-salinity wastewater Download PDFInfo
- Publication number
- CN217757168U CN217757168U CN202221903701.2U CN202221903701U CN217757168U CN 217757168 U CN217757168 U CN 217757168U CN 202221903701 U CN202221903701 U CN 202221903701U CN 217757168 U CN217757168 U CN 217757168U
- Authority
- CN
- China
- Prior art keywords
- nanofiltration
- water
- stage
- primary
- salinity wastewater
- 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.)
- Active
Links
Images
Landscapes
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The utility model discloses a water purification system that receives of high salt waste water strains belongs to the effluent treatment plant field. This receive and strain water purification system includes: a water inlet tank for collecting the pretreated high-salinity wastewater; a nanofiltration system used for separating the high-salinity wastewater from the pretreatment to obtain nanofiltration concentrated water and nanofiltration produced water; a freezing crystallization system for carrying out crystallization separation on nanofiltration concentrated water to generate mirabilite and freezing mother liquor; the membrane evaporation crystallization system is used for carrying out membrane evaporation crystallization on nanofiltration produced water to obtain sodium chloride and high-concentration mother liquor; the nanofiltration system comprises a primary multistage nanofiltration system and a secondary nanofiltration system; through the utility model discloses a nanofiltration system, the system all obtains guaranteeing to the entrapment rate of multivalent salt, to the rate of recovery of waste water, simultaneously, has reduced the whole investment cost of system.
Description
Technical Field
The utility model relates to a effluent treatment plant field, in particular to water purification system that receives of high salt waste water of straining.
Background
The nanofiltration salt separation technology is a membrane method salt separation treatment technology which is applied to the field of high-salinity wastewater in recent years, and is applied more frequently by one-stage three-section nanofiltration, but the interception effect of the single-stage nanofiltration on multivalent salt is continuously reduced along with the lapse of service time, so that the purity of crystallized salt on the nanofiltration water production side is reduced, the resource rate of the crystallized salt on the whole project is reduced, the salt impurity rate is increased, and the operation cost is increased.
With the continuous application of nanofiltration membranes in the field of high salt water, nanofiltration systems are also continuously updated, such as: the water produced by the primary nanofiltration is continuously treated by increasing the secondary nanofiltration, so that the retention rate of multivalent salt is improved, the increase of the secondary nanofiltration can reduce the overall wastewater recovery rate of the system, the water amount of the nanofiltration concentrated water side is increased, more monovalent salt enters the concentrated water side, the evaporation and crystallization of the concentrated water side are increased compositely, the investment cost is increased, the separation difficulty of the multivalent salt is increased, and the purity of the multivalent crystallized salt is reduced on the contrary.
Because the defect of two-stage nanofiltration is continuously shown, in order to better realize the separation of the crystallized salt, engineers develop a multistage and multistage nanofiltration system, namely: on the basis of the original two-stage nanofiltration, the concentrated water side continues to enter a nanofiltration system for treatment, the recovery rate of the nanofiltration system is improved while the high retention of multivalent salt by the nanofiltration system is ensured, but the low-pressure pipeline, the high-pressure pipeline, the water inlet pump, the high-pressure pump, the intermittent booster pump, system instruments and the like of the nanofiltration system are increased by multiple times while the nanofiltration system is continuously accumulated, so that the investment cost of the whole system is continuously increased, and compared with the single-stage nanofiltration, the investment cost of the two-stage multi-section nanofiltration system is more than 2.5 times that of the single-stage nanofiltration system, so that the investment cost is greatly increased.
SUMMERY OF THE UTILITY MODEL
To the above problem, the utility model provides a water purification system that receives strains of high salt waste water to solve above-mentioned problem.
The utility model aims at providing a high salt waste water receive filtration water purification system, include: a water inlet tank for collecting the pretreated high-salinity wastewater; a nanofiltration system for separating the pretreated high-salinity wastewater to obtain nanofiltration concentrated water and nanofiltration produced water; a freezing crystallization system for carrying out crystallization separation on nanofiltration concentrated water to generate mirabilite and freezing mother liquor; the membrane evaporation crystallization system is used for carrying out membrane evaporation crystallization on nanofiltration produced water to obtain sodium chloride and high-concentration mother liquor;
the nanofiltration system comprises a primary multistage nanofiltration system and a secondary nanofiltration system;
the water inlet tank is connected with a first-stage multi-section nanofiltration system through a high-pressure pump, the first-stage multi-section nanofiltration system separates pretreated high-salinity wastewater to obtain first-stage nanofiltration concentrated water and first-stage nanofiltration produced water, and a first-stage nanofiltration concentrated water outlet of the first-stage multi-section nanofiltration system is connected with a freezing crystallization system, so that the first-stage nanofiltration concentrated water enters the freezing crystallization system and mirabilite is separated out through the freezing crystallization system;
the primary nanofiltration water product enters the secondary nanofiltration system and passes through the secondary nanofiltration system to obtain secondary nanofiltration concentrated water and secondary nanofiltration water product, and a secondary nanofiltration water product outlet of the secondary nanofiltration system is connected with the membrane evaporation crystallization system, so that the secondary nanofiltration water product enters the membrane evaporation crystallization system and passes through the membrane evaporation crystallization system to obtain sodium chloride and high-concentration mother liquor; and the secondary nanofiltration concentrated water flows back to the primary multistage nanofiltration system.
Preferably, the method further comprises the following steps: the melting crystallization system is connected with the freezing crystallization system and is used for dissolving mirabilite to produce sodium sulfate; after being dissolved, the mirabilite enters a melt crystallization system and generates sodium sulfate through the melt crystallization system.
Preferably, the method further comprises the following steps: the mixed salt evaporative crystallization system is connected with the freezing crystallization system and the membrane evaporative crystallization system and is used for producing mixed salt; crystallizing to separate out mirabilite, recovering to obtain a frozen mother liquor, and allowing the high-concentration mother liquor to enter a mixed salt evaporation crystallization system to produce mixed salt.
Preferably, the pretreatment device is connected with the water inlet of the water inlet tank and used for pretreatment of high-salinity wastewater, and the pretreatment device is connected with the water inlet of the water inlet tank through a water inlet pump.
Preferably, the pretreatment device comprises a coagulating sedimentation device, a quartz sand filter and an ultrafiltration system, the high-salinity wastewater enters the coagulating sedimentation device and is removed of large-particle-size impurities through the coagulating sedimentation device, the high-salinity wastewater passing through the coagulating sedimentation device passes through a V-shaped filter tank and the ultrafiltration system for removing macromolecular organic matters, and the pretreated high-salinity wastewater is connected with the water inlet tank through a water inlet pump.
Preferably, the primary multi-section nanofiltration system comprises at least three sections of nanofiltration systems, nanofiltration water produced by the primary multi-section nanofiltration system is converged into the water production main pipe, and enters the secondary nanofiltration system through a secondary nanofiltration high-pressure pump.
Preferably, the first-stage multi-section nanofiltration system further comprises at least one intermittent booster pump arranged behind the first-stage two-section nanofiltration system.
Preferably, the osmotic pressure of the multivalent salt in the nanofiltration concentrated water on the nanofiltration membrane in the primary nanofiltration system or the secondary nanofiltration system does not exceed the highest osmotic pressure which can be resisted by the nanofiltration membrane.
Compared with the prior art, the utility model discloses following beneficial effect has:
the utility model provides a high salt waste water receive filtration water purification system receives filtration system includes that the one-level receives filtration system and second grade and receives filtration system. Compare with traditional nanofiltration system, the utility model discloses in, the one-level is received and is strained system level intersegmental section number through the increase, guarantees to receive the whole rate of recovery of straining the system, increases the water supply pressure that the booster pump guaranteed the end section and received the membrane through the section within a definite time, the utility model discloses a second grade is received and is strained one-level and receive production water, and the production water pipeline directly connects the second grade to receive and strain the water inlet and increase the pump, omits intake pump and middle pond, sets up high-pressure pump start-up time through automatic control system, guarantees the steady operation of the body system, and the second grade is received and is strained dense water and return and strain system intake pond.
Through the utility model discloses a receive filtration system, the system all obtains guaranteeing to the entrapment rate of multivalent salt, the rate of recovery to waste water, nevertheless contrasts the two-stage multistage system of receiving filtration, the utility model discloses to aspects such as the use quantity of the use amount of instrument, machine pump and system operation continuity, all obtained obvious promotion, simultaneously, reduced the whole investment cost of system.
Drawings
Fig. 1 is a process schematic diagram of a nanofiltration system provided by the utility model;
fig. 2 is a schematic flow diagram of a nanofiltration system provided by the present invention;
FIG. 3 is a schematic flow diagram of a one-stage three-stage nanofiltration system provided in comparative example 1;
fig. 4 is a schematic flow diagram of a two-stage nanofiltration system provided in comparative example 2;
fig. 5 is a schematic flow diagram of a two-stage multistage nanofiltration system provided in comparative example 3.
Detailed Description
In order to make the technical solution of the present invention better understood by those skilled in the art, a detailed description of an embodiment of the present invention is provided below with reference to the accompanying drawings, but it should be understood that the scope of the present invention is not limited by the embodiment.
The to-be-solved technical problem of the utility model lies in: the rejection rate of the traditional primary three-section nanofiltration system (figure 3) to multivalent salt is gradually reduced along with the operation of the system, so that the impurity salt rate and the operation cost of the whole project are increased; the two-stage nanofiltration system (figure 4) which appears recently has the problems of increased difficulty in separating salt on the nanofiltration concentrated water side, high yield of miscellaneous salt and the like; the two-stage multi-stage nanofiltration system (figure 5) has the problem of high investment cost. The utility model provides a receive and strain system can realize receiving and strain high entrapment rate, the high rate of recovery, the low investment cost receive and strain the system, has improved the separation efficiency of receiving and strain the system to monovalent salt and multivalent salt, and the miscellaneous salt productivity of reduction system reduces the holistic running cost of project.
The utility model provides a nanofiltration water purification system of high-salinity wastewater, as shown in figures 1-2, include: a water inlet tank for collecting the pretreated high-salinity wastewater; a nanofiltration system used for separating the high-salinity wastewater from the pretreatment to obtain nanofiltration concentrated water and nanofiltration produced water; a freezing crystallization system for carrying out crystallization separation on nanofiltration concentrated water to generate mirabilite and freezing mother liquor; the membrane evaporation crystallization system is used for carrying out membrane evaporation crystallization on nanofiltration produced water to obtain sodium chloride and high-concentration mother liquor;
specifically, the nanofiltration system comprises a primary multistage nanofiltration system and a secondary nanofiltration system; the water inlet tank is connected with a first-stage multi-stage nanofiltration system through a high-pressure pump, a water inlet pump and a security filter are arranged in front of the high-pressure pump, pretreated high-salt wastewater enters the first-stage multi-stage nanofiltration system to be separated to obtain first-stage nanofiltration concentrated water and first-stage nanofiltration produced water, a first-stage nanofiltration concentrated water outlet of the first-stage multi-stage nanofiltration system is connected with a freezing crystallization system, the first-stage nanofiltration concentrated water enters the freezing crystallization system to be frozen and crystallized to separate out mirabilite, and freezing mother liquor is recovered; the freezing crystallization system is connected with the melting crystallization system, and the produced mirabilite is dissolved and then enters the melting crystallization system to produce sodium sulfate;
furthermore, the primary multi-section nanofiltration system comprises at least three sections of nanofiltration systems, nanofiltration water produced by the primary multi-section nanofiltration system is converged into the water production main pipe, and enters the secondary nanofiltration system through a secondary nanofiltration high-pressure pump. And the first-stage multi-section nanofiltration system also comprises at least one break booster pump which is arranged behind the first-stage two-section nanofiltration system. And the osmotic pressure of multivalent salt in the nanofiltration concentrated water on the nanofiltration membrane in the primary nanofiltration system or the secondary nanofiltration system is not more than the highest osmotic pressure which can be resisted by the nanofiltration membrane.
The second-stage nanofiltration device is connected with the first-stage multi-stage nanofiltration device, the first-stage nanofiltration water production is converged into the second-stage nanofiltration device through a water production main pipe and passes through a second-stage nanofiltration system to obtain second-stage nanofiltration concentrated water and second-stage nanofiltration water production, and a second-stage nanofiltration water production outlet of the second-stage nanofiltration system is connected with the membrane evaporation crystallization system, so that the second-stage nanofiltration water production enters the membrane evaporation crystallization system and passes through the membrane evaporation crystallization system to obtain sodium chloride and high-concentration mother liquor; and the secondary nanofiltration concentrated water flows back to the primary multistage nanofiltration system. And after mirabilite is crystallized and separated out, the frozen mother liquor is recovered, the high-concentration mother liquor obtained by the membrane evaporation crystallization system enters a mixed salt evaporation crystallization system to produce mixed salt.
When high salt waste water is subjected to nanofiltration treatment, the water inlet requirement of a nanofiltration membrane system needs to be met, the high salt waste water is pretreated by adopting a pretreatment device before entering a water inlet tank, and the pretreatment device is connected with a water inlet of the water inlet tank through a water inlet pump. Specifically, the pretreatment device comprises a coagulating sedimentation device, a quartz sand filter and an ultrafiltration system, high-salinity wastewater enters the coagulating sedimentation device and is removed of large-particle-size impurities through the coagulating sedimentation device, the high-salinity wastewater passing through the coagulating sedimentation device then passes through a V-shaped filter tank and an ultrafiltration filter device for removing macromolecular organic matters, and the high-salinity wastewater after the pretreatment is connected with the water inlet tank through a water inlet pump.
The method comprises the following specific steps:
the utility model provides a novel nanofiltration arrangement and combination mode, which is based on the high saline water inflow of 100m 3 For example,/h, the inlet water quality of the nanofiltration system is as TDS:30000mg/L, cl - :10000mg/L, SO42-:8800mg/L, na +:10000mg/L, the rest containing trace amount of K + 、Ca 2+ 、Mg 2+ 、NO 3- COD, SS, etc.
(1) Receive system of straining and intake and need satisfy membrane system requirement of intaking, get into the utility model provides a receive system of straining and expect unanimously with other system's of straining that intake, promptly: pretreatment devices such as a coagulating sedimentation device, a quartz sand filter device and an ultrafiltration device need to be arranged in front of the nanofiltration system to pretreat the high-salinity wastewater so as to meet the water inlet requirement of the membrane system.
(2) According to the utility model discloses, the overall recovery rate of system design is 83.9%, through calculating, among the one-level multistage system of receiving filtration, first section design recovery rate 30%, second section design recovery rate 30%, third sectionThe designed recovery rate is 30%, the designed recovery rate is 30% in the fourth stage, the designed recovery rate is 25% in the fifth stage, and the designed recovery rate is 20% in the sixth stage; the designed recovery rate of the secondary nanofiltration is 88 percent, and the water produced by the secondary nanofiltration, namely the sodium chloride in the final nanofiltration water production, accounts for 98.9 percent, and has the water content: 83.9m 3 H; the sodium sulfate in the nanofiltration concentrated water accounts for 86.1 percent, and the water amount is 16.1m 3 /h；
(3) The water produced by the nanofiltration system is further concentrated and then enters a sodium chloride evaporative crystallization system to produce sodium chloride and a small amount of sodium chloride crystallization mother liquor;
(4) The nanofiltration concentrated water obtained by the primary multistage nanofiltration system enters a freezing crystallization system to produce mirabilite, and the mirabilite is dissolved and then enters a melting crystallization system to produce sodium sulfate;
(5) And the freezing mother liquor recovered after the freezing crystallization system produces the mirabilite is mixed with the sodium chloride crystallization mother liquor and then enters a mixed salt evaporation crystallization system to produce a small amount of mixed salt.
Finally, compared with a two-stage multi-section nanofiltration system, the low-investment nanofiltration system of the utility model saves the total nanofiltration investment cost by more than 1/3;
compared with a two-stage nanofiltration system, the nanofiltration concentrated water is greatly reduced, the load of evaporative crystallization treatment on the nanofiltration concentrated water side is greatly reduced, and the yield of miscellaneous salt is reduced by about 30 percent;
compared with a first-stage three-section nanofiltration system, the investment cost is increased by about 60%, but the yield of miscellaneous salt is reduced by more than 50%, so that the operation cost of wastewater treatment is greatly reduced.
Comparative example 1 first stage three-section nanofiltration System
The first-stage three-section nanofiltration system comprises a high-salinity wastewater inlet pool used for collecting pretreated high-salinity wastewater and a first-stage three-section nanofiltration system used for separating the pretreated high-salinity wastewater to obtain nanofiltration concentrated water and nanofiltration produced water. The high-salinity wastewater inlet tank is connected with the first-stage three-section nanofiltration system through the inlet pump, the security filter and the high-pressure pump.
The method comprises the following steps that high-salinity wastewater is pretreated through coagulating sedimentation, a V-shaped filter tank and ultrafiltration filtration to remove impurities with large particle sizes and macromolecular organic matters, the pretreated wastewater enters a water inlet tank of a nanofiltration system, and sequentially passes through a first-stage nanofiltration system, a first-stage second-stage nanofiltration system and a first-stage third-stage nanofiltration system through a high-pressure pump, a booster pump is arranged between the first-stage second-stage nanofiltration system and the first-stage third-stage nanofiltration system, and nanofiltration concentrated water generated after the first-stage third-stage nanofiltration system is used as final nanofiltration concentrated water of the nanofiltration system; the nanofiltration water produced after passing through the first three-stage nanofiltration system is used as the final nanofiltration water produced by the nanofiltration system, as shown in fig. 3.
Comparative example 2 two-stage nanofiltration System
The two-stage nanofiltration system comprises a high-salinity wastewater inlet pool for collecting pretreated high-salinity wastewater, a first-stage nanofiltration system for separating the pretreated high-salinity wastewater to obtain first-stage nanofiltration concentrated water and first-stage nanofiltration produced water, and a second-stage nanofiltration system for separating the nanofiltration produced water obtained by the first-stage nanofiltration system to obtain second-stage nanofiltration concentrated water and second-stage nanofiltration produced water. The high-salinity wastewater inlet tank is connected with a primary nanofiltration system through an inlet pump, a security filter and a high-pressure pump, primary nanofiltration concentrated water and primary nanofiltration produced water are obtained through a primary nanofiltration device, the primary nanofiltration produced water enters a nanofiltration water production intermediate tank, then enters a secondary nanofiltration system through the inlet pump, the security filter and the high-pressure pump, and is separated through the secondary nanofiltration system to obtain secondary nanofiltration produced water and secondary nanofiltration concentrated water.
The method comprises the following steps that high-salinity wastewater is pretreated through coagulating sedimentation, a V-shaped filter tank and ultrafiltration filtration to remove impurities with large particle sizes and macromolecular organic matters, the pretreated wastewater enters a water inlet tank of a primary nanofiltration system and enters the primary nanofiltration system through a primary nanofiltration high-pressure pump, specifically, the primary nanofiltration system comprises a primary one-section nanofiltration system, a primary two-section nanofiltration system and a primary three-section nanofiltration system, the pretreated wastewater sequentially passes through the primary one-section nanofiltration system, the primary two-section nanofiltration system and the primary three-section nanofiltration system, and a booster pump is arranged between the primary two-section nanofiltration system and the primary three-section nanofiltration system; the concentrated water is subjected to primary multi-section nanofiltration to generate concentrated water;
the nanofiltration water produced by the first-stage multi-section nanofiltration membrane system is a first-stage nanofiltration water produced by the first-stage multi-section nanofiltration system, a second-stage nanofiltration water produced by the first-stage second-stage nanofiltration system, and a third-stage nanofiltration water produced by the first-stage three-stage nanofiltration system, and the three-stage nanofiltration water produced by the first-stage three-stage nanofiltration system are converged into a water production main pipe, enter a second-stage nanofiltration system water inlet pool, enter a second-stage nanofiltration high-pressure pump, and are combined with the first-stage nanofiltration concentrated water produced by the second-stage nanofiltration system to be used as final nanofiltration concentrated water of the nanofiltration system; the nanofiltration water product permeated through the secondary nanofiltration system is used as the final nanofiltration water product of the nanofiltration system, as shown in fig. 4.
Comparative example 3 two-stage multistage nanofiltration System
The two-stage multi-section nanofiltration system comprises a water inlet pool for collecting pretreated high-salinity wastewater, a first primary nanofiltration system for separating the pretreated wastewater to obtain first primary nanofiltration concentrated water and first primary nanofiltration produced water, a second primary nanofiltration system for treating the first primary nanofiltration concentrated water to obtain second primary nanofiltration concentrated water and second primary nanofiltration produced water, a first primary nanofiltration water producing pool for combining the first primary nanofiltration produced water and the second primary nanofiltration produced water into nanofiltration produced water, and a second primary nanofiltration system connected with the first primary nanofiltration water producing pool through a water inlet pump, a security filter and a high-pressure pump, wherein the nanofiltration produced water enters the second primary nanofiltration system to be separated into final nanofiltration produced water and second nanofiltration concentrated water, and the second nanofiltration concentrated water flows back to a concentrated water middle water pool.
The method comprises the following steps that high-salinity wastewater is pretreated through coagulating sedimentation, a V-shaped filter tank and ultrafiltration filtration to remove impurities with large particle diameters and macromolecular organic matters, the pretreated wastewater enters a water inlet tank of a first primary nanofiltration system and passes through the first primary nanofiltration system through a first primary nanofiltration high-pressure pump, specifically, the first primary nanofiltration system comprises a first primary one-stage nanofiltration system, a first primary two-stage nanofiltration system and a first primary three-stage nanofiltration system, the pretreated high-salinity wastewater sequentially passes through the first primary one-stage nanofiltration system, the first primary one-stage two-stage nanofiltration system and the first primary three-stage nanofiltration system, and a first booster pump is arranged between the first primary one-stage two-stage nanofiltration system and the first primary three-stage nanofiltration system; after passing through the first one-stage multi-section nanofiltration system, first one-stage nanofiltration concentrated water and first one-stage nanofiltration produced water are produced;
the method comprises the following steps that first primary nanofiltration concentrated water enters a concentrated water intermediate water tank and enters a second primary nanofiltration system through a second primary nanofiltration high-pressure pump, the specific second primary nanofiltration system comprises a second primary one-section nanofiltration system, a second primary two-section nanofiltration system and a second primary three-section nanofiltration system, the first primary nanofiltration concentrated water sequentially enters the second primary one-section nanofiltration system, the second primary two-section nanofiltration system and the second primary three-section nanofiltration system, and a second booster pump is arranged between the second primary one-section nanofiltration system and the second primary three-section nanofiltration system; the second-stage nanofiltration concentrated water generated by the second-stage three-section nanofiltration system is used as final nanofiltration concentrated water of the nanofiltration system;
the first primary nanofiltration water production comprises first primary section nanofiltration water production which is penetrated by the first primary section nanofiltration system, first primary section nanofiltration water production which is penetrated by the first primary section nanofiltration system, and first primary section nanofiltration water production which is penetrated by the first primary section nanofiltration system,
the first-stage nanofiltration water production system comprises a first-stage nanofiltration water production system, a first-stage nanofiltration water production system and a second-stage nanofiltration water production system, wherein the first-stage nanofiltration water production system comprises a first-stage nanofiltration water production pipe and a first-stage nanofiltration water production pipe; the nanofiltration water product permeated through the secondary nanofiltration system is used as the final nanofiltration water product of the nanofiltration system, as shown in fig. 5.
In order to further verify the utility model relates to an improve branch salt method of high salt waste water relative productivity of salt crystal to the high salt waste water that contains divide the salt effect, combine the attached drawing to the high salt industrial waste water zero release project that contains of certain coal chemical industry project explains as an example.
Example 1
After the inlet water of the project is subjected to coagulating sedimentation, V-shaped filter tank and ultrafiltration filtration, the inlet water amount of the nanofiltration device is 50m & lt 3 & gt/h, and the water quality is COD:160mg/L; pH:7.2; ca 2+ ：51.9mg/L；Mg 2+ ：13.6mg/L；Na + ：8797.7mg/L；K + ：79.1mg/L；Cl - ：8672.7mg/L；SO 4 2- ：6850.9mg/L；NO 3 - ：68.5mg/L；F - ：3.3mg/L；SiO 2 ：9.5mg/L；TDS：24548.2mg/L。
(1) The nanofiltration system of the utility model is two-stage, wherein the design of the nanofiltration system of one stage is 6 sections, the recovery rate is 30 percent, wherein, 1 water inlet pump and 1 high pressure pump are arranged (the flow rate is Q =62 m) 3 H, lift: h =220 m), 2 intermittent booster pumps provided after 2 stages (flow rate: q =30m 3 H, lift: h =120m, inlet pressure: 22 bar) and after 5 stages (flow: q =12m 3 H, lift: h =60m, inlet pressure: 34 bar), the water inlet, the water production, the concentrated water quantity and the water quality of each section are shown in the table 1, wherein 6 sections of concentrated water are used as final concentrated water of the nanofiltration system;
(2) Respectively converging the water produced by each section of nanofiltration system into a water production main pipe, and then connecting the water production main pipe with an inlet of a second-stage nanofiltration high-pressure pump, wherein the recovery rate of the second-stage nanofiltration design is 88%, the produced water is used as final nanofiltration produced water, and concentrated water flows back to a nanofiltration system water inlet pool;
(3) The water yield of the second-stage nanofiltration is as follows: 43.4m 3 The water quality is as follows: COD:77.5mg/L; pH:7.1; ca 2+ ：1.0mg/L；Mg 2+ ：0.3mg/L；Na + ：5582.4mg/L；K + ：74.3mg/L；Cl - ：8623.7mg/L；SO 4 2- ：32.8mg/L；NO 3 - ：58.9mg/L；F - ：2.8mg/L；SiO 2 :8.9mg/L; TDS:14385.7mg/L. The final produced water used as the nanofiltration system is concentrated by a subsequent membrane system and an evaporation system, and then enters a sodium chloride evaporation crystallization system to produce sodium chloride crystal salt with the high purity of 99.1 percent, and the residual high-concentration mother liquor is 0.1m 3 Entering a miscellaneous salt crystallization system;
(4) The nanofiltration concentrated water firstly enters a freezing crystallization system to produce mirabilite, sodium sulfate with the purity of 99.6 percent is produced by melting crystallization after being dissolved, and the freezing mother liquor enters mixed salt crystallization after being partially recovered;
(5) Finally, the project produces 0.59t/h of sodium chloride, 0.51t/h of sodium sulfate and 0.1t/h of miscellaneous salt, and the yield of miscellaneous salt is greatly reduced.
The embodiment adopts the utility model discloses a nanofiltration system uses with the nanofiltration system of other modes to say table 2.
Table 1 summary of inter-primary nanofiltration water quality in example 1
TABLE 2 comparison of the service conditions of the nanofiltration systems of example 1 and comparative examples 1 to 3 of the present invention
Example 2
In this embodiment, a mine water zero discharge project is taken as an example for explanation.
In the embodiment, the inlet water passes through a coagulating sedimentation tank, a V-shaped filter tank, ultrafiltration filtration, reverse osmosis concentration and an advanced oxidation device, and the inlet water amount of the nanofiltration device is 70m 3 H, the water quality is COD:180mg/L; pH:7.5; ca 2+ ：47.8mg/L；Mg 2+ ：23.5mg/L；Na + ：18062.8mg/L；K + ：43.8mg/L；Cl - ：13003.5mg/L；SO 4 2- ：20244.3mg/L；NO 3 - ：163.5mg/L；F - ：2.3mg/L；SiO 2 ：33.5mg/L；TDS：51625.5mg/L。
(1) The nanofiltration system of the project is two-stage, wherein the nanofiltration of one stage is designed into 3 sections, the recovery rates are respectively 30%, 30% and 25%, wherein 1 water inlet pump and 1 high pressure pump are arranged (the flow rate is Q =83 m) 3 H, lift: h =320 m), 1 intermittent booster pump, provided after 2 stages (flow rate: q =40m 3 H, lift: h =90m, inlet pressure: 32 bar), the water inlet, the water production, the concentrated water quantity and the water quality of each section are shown in a table 3, wherein the concentrated water of 3 sections is used as final concentrated water of the nanofiltration system;
(2) The water produced by each section of nanofiltration system is respectively converged into a water production main pipe and then is connected with an inlet of a secondary nanofiltration high-pressure pump, the recovery rate of the secondary nanofiltration design is 87 percent, the produced water is used as the final nanofiltration produced water, and the concentrated water flows back to a water inlet tank of the nanofiltration system;
(3) The water yield of the second-stage nanofiltration is as follows: 42.0m 3 The water quality is as follows: COD:60.6mg/L; pH:7.1; ca 2+ ：0.6mg/L；Mg 2+ ：0.3mg/L；Na + ：10099.0mg/L；K + ：38.5mg/L；Cl - ：15504.2mg/L；SO 4 2- ：64.1mg/L；NO 3 - ：122.1mg/L；F - ：1.7mg/L；SiO 2 :29.4mg/L; TDS:25859.9mg/L. The final produced water used as the nanofiltration system is concentrated by a subsequent membrane system and an evaporation system, and then enters a sodium chloride evaporation crystallization system to produce sodium chloride crystal salt with high purity of 99.3 percent, and the residual high-concentration mother liquor is 0.08m 3 Entering a miscellaneous salt crystallization system;
(4) The nanofiltration concentrated water firstly enters a freezing crystallization system to produce mirabilite, sodium sulfate with the purity of 99.5 percent is produced by melting crystallization after being dissolved, and the freezing mother liquor enters mixed salt crystallization after being partially recovered;
(5) Finally, 0.95t/h of sodium chloride, 2.40t/h of sodium sulfate and 0.26t/h of miscellaneous salt are produced in the embodiment, and the yield of miscellaneous salt is greatly reduced.
This embodiment adopts the utility model discloses use with other mode equipment to say table 4.
TABLE 3 Collection of Water quality between first-stage nanofiltration interruptions in example 2
Table 4 example 2 comparison of low cost nanofiltration with other array combination type equipment
In the utility model, the single-stage nanofiltration adopts a multi-stage design, no middle water tank is arranged, only the intermittent booster pump is arranged, the start-stop time of the pump is set through an automatic control system, and the dry start is avoided;
the secondary nanofiltration concentrated water returns to the front of the high-pressure pump of the primary nanofiltration system so as to improve the overall recovery rate of the system and contribute to improving the flow rate of the concentrated water in the membrane system, so that a concentrated water return pipeline can be omitted during the design of the system;
the utility model discloses need not to set up equipment such as middle pond, intake pump, the high-pressure pump that the multistage was received and is strained, and then practice thrift instrument, valve, pipeline etc. that need set up such as pond, motor-pump, reduce investment cost.
The above disclosure is only for a few specific embodiments of the present invention, however, the present invention is not limited to the embodiments, and any changes that can be considered by those skilled in the art shall fall within the protection scope of the present invention.
Claims (8)
1. A nanofiltration water purification system of high-salinity wastewater is characterized by comprising: a water inlet tank for collecting the pretreated high-salinity wastewater; a nanofiltration system for separating the pretreated high-salinity wastewater to obtain nanofiltration concentrated water and nanofiltration produced water; a freezing crystallization system for carrying out crystallization separation on the nanofiltration concentrated water to generate mirabilite and freezing mother liquor; the membrane evaporation crystallization system is used for carrying out membrane evaporation crystallization on nanofiltration produced water to obtain sodium chloride and high-concentration mother liquor;
the nanofiltration system comprises a primary multistage nanofiltration system and a secondary nanofiltration system;
the water inlet tank is connected with a first-stage multi-stage nanofiltration system through a high-pressure pump, the first-stage multi-stage nanofiltration system separates pretreated high-salinity wastewater to obtain first-stage nanofiltration concentrated water and first-stage nanofiltration produced water, and a first-stage nanofiltration concentrated water outlet of the first-stage multi-stage nanofiltration system is connected with a freezing crystallization system, so that the first-stage nanofiltration concentrated water enters the freezing crystallization system and mirabilite is separated out through the freezing crystallization system;
the primary nanofiltration water product enters the secondary nanofiltration system and passes through the secondary nanofiltration system to obtain secondary nanofiltration concentrated water and secondary nanofiltration water product, and a secondary nanofiltration water product outlet of the secondary nanofiltration system is connected with the membrane evaporation crystallization system, so that the secondary nanofiltration water product enters the membrane evaporation crystallization system and passes through the membrane evaporation crystallization system to obtain sodium chloride and high-concentration mother liquor; and the secondary nanofiltration concentrated water flows back to the primary multistage nanofiltration system.
2. The nanofiltration water purification system of high-salinity wastewater according to claim 1, further comprising: the melting crystallization system is connected with the freezing crystallization system and is used for dissolving mirabilite to produce sodium sulfate; after being dissolved, the mirabilite enters a melt crystallization system and generates sodium sulfate through the melt crystallization system.
3. The nanofiltration water purification system of high-salinity wastewater according to claim 2, further comprising: the mixed salt evaporative crystallization system is connected with the freezing crystallization system and the membrane evaporative crystallization system and is used for producing mixed salt; crystallizing to separate out mirabilite, recovering to obtain a frozen mother liquor, and allowing the high-concentration mother liquor to enter a mixed salt evaporation crystallization system to produce mixed salt.
4. The nanofiltration water purification system of high-salinity wastewater according to claim 1, further comprising a pretreatment device connected to the inlet of the inlet tank and used for pretreatment of high-salinity wastewater, wherein the pretreatment device is connected to the inlet of the inlet tank through an inlet pump.
5. The nanofiltration water purification system of claim 4, wherein the pretreatment device comprises a coagulating sedimentation device, a quartz sand filter and an ultrafiltration system, the high-salinity wastewater enters the coagulating sedimentation device and is treated by the coagulating sedimentation device to remove large-particle-size impurities, the high-salinity wastewater passing through the coagulating sedimentation device passes through the V-shaped filter tank for removing large-molecular organic matters and the ultrafiltration system, and the pretreated high-salinity wastewater is connected with the water inlet tank through a water inlet pump.
6. The nanofiltration water purification system of claim 1, wherein the primary multi-stage nanofiltration system comprises at least three nanofiltration systems, and nanofiltration water produced by the primary multi-stage nanofiltration system is collected into the water production main pipe and enters the secondary nanofiltration system through a secondary nanofiltration high-pressure pump.
7. The nanofiltration water purification system of high-salinity wastewater according to claim 6, wherein the primary multi-stage nanofiltration system further comprises at least one intermittent booster pump arranged after the primary two-stage nanofiltration system.
8. The nanofiltration water purification system of high-salinity wastewater according to claim 1, wherein the osmotic pressure of multivalent salts in the nanofiltration concentrated water on the nanofiltration membrane in the primary nanofiltration system or the secondary nanofiltration system does not exceed the highest osmotic pressure that the nanofiltration membrane can resist.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221903701.2U CN217757168U (en) | 2022-07-23 | 2022-07-23 | Nanofiltration water purification system for high-salinity wastewater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221903701.2U CN217757168U (en) | 2022-07-23 | 2022-07-23 | Nanofiltration water purification system for high-salinity wastewater |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN217757168U true CN217757168U (en) | 2022-11-08 |
Family
ID=83875639
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202221903701.2U Active CN217757168U (en) | 2022-07-23 | 2022-07-23 | Nanofiltration water purification system for high-salinity wastewater |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN217757168U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116354454A (en) * | 2022-11-16 | 2023-06-30 | 内蒙古滟晴环境技术有限公司 | Nanofiltration system, system and method for treating high-concentration brine |
-
2022
- 2022-07-23 CN CN202221903701.2U patent/CN217757168U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116354454A (en) * | 2022-11-16 | 2023-06-30 | 内蒙古滟晴环境技术有限公司 | Nanofiltration system, system and method for treating high-concentration brine |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108117222B (en) | Zero-discharge treatment method for salt-containing wastewater in coal chemical industry | |
| CN108117207B (en) | Zero-discharge treatment process method for salt-containing wastewater | |
| TWI393678B (en) | Desalination system | |
| CN108314064B (en) | Full-membrane separation method for producing lithium extraction mother liquor by multi-stage membrane concentration of salt lake brine | |
| US11219864B2 (en) | Method for efficient separation and enrichment of lithium | |
| CN108314065B (en) | Full-membrane separation method for producing lithium extraction mother liquor by multi-stage nanofiltration separation of salt lake brine | |
| CN108117206B (en) | Zero-discharge treatment process method for salt-containing wastewater | |
| US20200330925A1 (en) | Method for separation and enrichment of lithium | |
| CN111661900B (en) | System and method for low-pressure high-power concentration of high-salinity wastewater | |
| US20200306696A1 (en) | Method for separation and enrichment of lithium | |
| CN115571950B (en) | Salt lake lithium extraction process | |
| CN110734166A (en) | method for efficient desalination and comprehensive utilization of seawater | |
| CN104609610A (en) | Method for treating reverse osmosis concentrated water and circulating wastewater by whole membrane method | |
| CN217757168U (en) | Nanofiltration water purification system for high-salinity wastewater | |
| CN115571951B (en) | Lithium production system is carried in salt lake | |
| CN104817134A (en) | Full-membrane method seawater desalting integration system adopting ultrafiltration-nanofiltration-reverse osmosis, and full-membrane method seawater desalting integration process adopting ultrafiltration-nanofiltration-reverse osmosis | |
| CN112679020B (en) | Low-cost shale gas fracturing flowback fluid treatment system and treatment method | |
| CN113562917B (en) | High-recovery-rate seawater desalination process | |
| CN211620231U (en) | Device for efficient desalination and comprehensive utilization of seawater | |
| CN114870633B (en) | Process for enriching lithium in salt lake brine | |
| CN111888941A (en) | Heparin sodium membrane integration process | |
| CN115108673B (en) | Recycling process for ferric phosphate mother liquor produced by oxidation method | |
| CN115991560A (en) | Treatment method for recycling iron phosphate production wastewater | |
| CN216472254U (en) | Sulfuric acid process titanium white powder is washed weak waste acid membrane integration resourceful treatment system once | |
| CN212894299U (en) | Heparin sodium wastewater resourceful treatment's system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |