CN-224212545-U - Treatment system for concentrated water liquid of lithium phosphate production line

CN224212545UCN 224212545 UCN224212545 UCN 224212545UCN-224212545-U

Abstract

The utility model discloses a treatment system of concentrated water liquid of a lithium phosphate production line, which comprises a wastewater storage tank, a freezing reaction kettle, a centrifugal device, an evaporation reaction kettle and a liquid storage tank. The treatment system can effectively treat the concentrated water to obtain high-purity byproduct sodium sulfate and sodium chloride mixed salt under the conditions of low energy consumption and simple operation, and can further perform system optimization on the treatment system, including the addition of a circulating treatment device, a nanofiltration device and the like of an evaporation reaction kettle, so that the high-purity byproduct sodium sulfate can be obtained while the concentrated water is treated to obtain high-purity sodium chloride.

Inventors

ZHANG TENG
SUN PENG
SHI YINGFEI
Lv Congjiang
SHI JUNFENG

Assignees

山东美多科技有限公司
江苏龙蟠科技股份有限公司
龙蟠科技(亚太)有限公司

Dates

Publication Date: 20260508
Application Date: 20250521

Claims (8)

1. A system for treating concentrated aqueous solution of a lithium phosphate production line, which is characterized by comprising: a waste water storage tank (1) for collecting and storing concentrated water liquid of the lithium phosphate production line; The freezing reaction kettle (2) is connected with the discharge end of the wastewater storage tank (1) to cool the concentrated water solution to realize low-temperature crystallization of mirabilite; the feeding end of the first centrifugal device (3) is connected with the discharging end of the freezing reaction kettle (2) to realize solid-liquid separation in the freezing reaction kettle (2) and obtain mirabilite crystals and slurry; The feeding end of the first evaporation reaction kettle (4) is connected with the slurry discharging end of the first centrifugal device (3), and excessive water in the evaporated slurry is separated out until sodium chloride is separated out, so that new slurry is obtained; The feeding end of the second centrifugal device (5) is connected with the discharging end of the first evaporation reaction kettle (4), so that solid-liquid separation of slurry obtained in the first evaporation reaction kettle (4) is realized, and mixed salt and new slurry are obtained; The feed end of the liquid storage tank (6) is connected with the slurry discharge end of the second centrifugal device (5), and the discharge end of the liquid storage tank is circularly connected to the feed end of the first evaporation reaction kettle (4) through a pipeline.
2. A system for treating concentrated aqueous solution of a lithium phosphate production line, which is characterized by comprising: a waste water storage tank (1) for collecting and storing concentrated water liquid of the lithium phosphate production line; The freezing reaction kettle (2) is connected with the discharge end of the wastewater storage tank (1) to cool the concentrated water solution to realize low-temperature crystallization of mirabilite; the feeding end of the first centrifugal device (3) is connected with the discharging end of the freezing reaction kettle (2) to realize solid-liquid separation in the freezing reaction kettle (2) and obtain mirabilite crystals and slurry; the feeding end of the first evaporation reaction kettle (4) is connected with the slurry discharging end of the first centrifugal device (3), and excessive water in the evaporated slurry is saturated with sodium chloride to obtain new slurry, wherein the discharging end of the first evaporation reaction kettle (4) is circulated into the freezing reaction kettle (2) through a pipeline so as to enable the new slurry to be frozen and crystallized in a circulating way; The second evaporation reaction kettle (7) is connected with the discharge end of the slurry obtained by the circulation freezing crystallization of the first centrifugal device (3) so as to evaporate redundant water of the slurry obtained by the circulation freezing crystallization until sodium chloride is separated out, thus obtaining new slurry; The feeding end of the second centrifugal device (5) is connected with the discharging end of the second evaporation reaction kettle (7), so that solid-liquid separation of slurry obtained in the second evaporation reaction kettle (7) is realized, and high-purity sodium chloride and new slurry are obtained; The feed end of the liquid storage tank (6) is connected with the slurry discharge end of the second centrifugal device (5), and the discharge end of the liquid storage tank is circularly connected to the feed end of the second evaporation reaction kettle (7) through a pipeline, and the liquid storage tank is circularly evaporated and crystallized again.
3. A system for treating concentrated aqueous solution of a lithium phosphate production line, which is characterized by comprising: a waste water storage tank (1) for collecting and storing concentrated water liquid of the lithium phosphate production line; The freezing reaction kettle (2) is connected with the discharge end of the wastewater storage tank (1) to cool the concentrated water solution so as to realize low-temperature crystallization of mirabilite; the feeding end of the first centrifugal device (3) is connected with the discharging end of the freezing reaction kettle (2) to realize solid-liquid separation in the freezing reaction kettle (2) and obtain mirabilite crystals and slurry; The feeding end of the first evaporation reaction kettle (4) is connected with the slurry discharging end of the first centrifugal device (3), and excessive water in the evaporation slurry is evaporated to be saturated with sodium chloride, so that new slurry is obtained; The feeding end of the nanofiltration equipment (8) is connected with the discharging end of the first evaporation reaction kettle (4) so as to intercept sodium sulfate in the slurry and obtain pure sodium chloride slurry; And the concentration reaction kettle (12) is connected with a sodium chloride slurry discharge port of the nanofiltration equipment (8) so as to concentrate and obtain sodium chloride.
4. A system for treating concentrated aqueous solution of a lithium phosphate production line, which is characterized by comprising: a waste water storage tank (1) for collecting and storing concentrated water liquid of the lithium phosphate production line; The freezing reaction kettle (2) is connected with the discharge end of the wastewater storage tank (1) to cool the concentrated water solution so as to realize low-temperature crystallization of mirabilite; The feeding end of the first centrifugal device (3) is connected with the discharging end of the freezing reaction kettle (2) to realize solid-liquid separation in the freezing reaction kettle and obtain mirabilite crystals and slurry; The feeding end of the nanofiltration equipment (8) is connected with the discharging end of the first centrifugal device (3) so as to intercept sodium sulfate in the slurry and obtain pure sodium chloride slurry; The feeding end of the first evaporation reaction kettle (4) is connected with the discharge end of sodium chloride slurry of the nanofiltration equipment (8), and excessive water in the evaporated sodium chloride slurry is evaporated until sodium chloride is separated out, so that new slurry is obtained; the feeding end of the second centrifugal device (5) is connected with the discharging end of the first evaporation reaction kettle (4), so that solid-liquid separation of slurry obtained in the first evaporation reaction kettle (4) is realized, and high-purity sodium chloride and new slurry are obtained; The feed end of the liquid storage tank (6) is connected with the slurry discharge end of the second centrifugal device (5), and the discharge end of the liquid storage tank is circularly connected to the feed end of the first evaporation reaction kettle (4) through a pipeline, and the liquid storage tank is circularly evaporated and crystallized again.
5. The system for treating concentrated aqueous solution of lithium phosphate production line according to any one of claims 1 to 4, wherein the mirabilite crystal discharge end of the first centrifugal device (3) is further provided with a mirabilite dissolving tank (9) and an MVR device (10) in a sequentially connected manner.
6. The system for treating concentrated aqueous liquid in lithium phosphate production line according to claim 5, wherein a sodium sulfate discharge port of the nanofiltration device (8) is circulated to a feed end of the mirabilite dissolution tank (9) through a pipeline.
7. The system for treating concentrated aqueous solutions of lithium phosphate production lines according to any one of claims 1 to 4, further comprising a water cooling device (11) for supplying circulating cooling water to the freezing reactor (2).
8. The system for treating concentrated aqueous solutions in a lithium phosphate production line according to any one of claims 1 to 4, further comprising a steam generating device for supplying steam to the evaporation reactor.

Description

Treatment system for concentrated water liquid of lithium phosphate production line Technical Field The utility model belongs to the field of water treatment systems, and particularly relates to a treatment system for concentrated water liquid of a lithium phosphate production line. Background In the production line for preparing lithium phosphate by recycling waste battery powder, the material liquid is continuously concentrated and circulated in a system, a large amount of concentrated water liquid is continuously accumulated, and the concentrated water liquid usually contains a large amount of soluble inorganic salts such as chloride ions, sulfate radicals, phosphate radicals, sodium ions and the like. The concentrated aqueous solution is distributed throughout each plant, and no matter the production addition, the system circulation or the wastewater treatment regeneration circulation, the concentrated aqueous solution with higher salt content can be produced. The continuous accumulation and enrichment of the soluble inorganic salt can lead to the reduction of the evaporation efficiency of a production line and the increase of the operation cost, and even can lead to the paralysis of equipment when serious, and influence the quality of lithium phosphate products, so that concentrated water needs to be subjected to periodic open-circuit treatment. Because of the extremely high difficulty in treating concentrated aqueous solutions, efficient and reliable methods are needed for the abatement treatment. The current treatment mode of concentrated water mainly comprises biochemical and membrane filtration combined technology, low-temperature vacuum drying technology, salt-containing waste liquid concentration crystallization system, filter plate device and other technologies. Although the effluent discharged by the process can achieve the up-to-standard discharge, the problems of large occupied area of complete equipment, high input cost and disposal cost, long installation period, low filtration efficiency, difficult self-cleaning of impurities and the like exist. Based on this, design to current production line now, research a novel lithium phosphate production line dense water liquid processing system to reach and to put into use in time, solve the current problem of production line, equipment installation and easy operation, and can effectively promote production efficiency's purpose. Disclosure of utility model The utility model aims to solve the technical problem of providing a novel concentrated water treatment system for a lithium phosphate production line, which has the advantages of long service life, convenient operation and high operation efficiency, and can obtain high-purity mirabilite, mixed salt or high-purity sodium chloride byproducts. The technical scheme is that the treatment system of the concentrated water solution of the lithium phosphate production line comprises: A waste water storage tank for collecting and storing concentrated water liquid of the lithium phosphate production line; The freezing reaction kettle is connected with the discharge end of the wastewater storage tank to cool the concentrated water solution to realize low-temperature crystallization of mirabilite; The first centrifugal device is connected with the feeding end of the freezing reaction kettle and is used for realizing solid-liquid separation in the freezing reaction kettle to obtain mirabilite crystals and slurry; The feeding end of the first evaporation reaction kettle is connected with the slurry discharging end of the first centrifugal device, and excessive water in the slurry is evaporated until sodium chloride is separated out, so that new slurry is obtained; The second centrifugal device is connected with the discharge end of the first evaporation reaction kettle at the feed end, so that solid-liquid separation of slurry obtained in the first evaporation reaction kettle is realized, and mixed salt and new slurry are obtained; The liquid storage tank is connected with the slurry discharge end of the second centrifugal device at the feed end, and the discharge end of the liquid storage tank is circularly connected to the feed end of the first evaporation reaction kettle through a pipeline. Further, the treatment system of the concentrated aqueous solution of the lithium phosphate production line can also be as follows: A waste water storage tank for collecting and storing concentrated water liquid of the lithium phosphate production line; The freezing reaction kettle is connected with the discharge end of the wastewater storage tank to cool the concentrated water solution to realize low-temperature crystallization of mirabilite; The first centrifugal device is connected with the feeding end of the freezing reaction kettle and is used for realizing solid-liquid separation in the freezing reaction kettle to obtain mirabilite crystals and slurry; The feeding end of the first evaporation reaction kettle is conn