CN114931917B

CN114931917B - Positive electrode material precursor coprecipitation reaction system

Info

Publication number: CN114931917B
Application number: CN202210366776.XA
Authority: CN
Inventors: 何志; 许锦鹏; 杨光耀; 康彬; 何劲松
Original assignee: Sichuan Sidaneng Environmental Protection Technology Co ltd; Chengdu Stareng Environmental Protection Equipment Co ltd
Current assignee: Sichuan Sidaneng Environmental Protection Technology Co ltd; Chengdu Stareng Environmental Protection Equipment Co ltd
Priority date: 2022-04-08
Filing date: 2022-04-08
Publication date: 2024-04-30
Anticipated expiration: 2042-04-08
Also published as: CN114931917A

Abstract

The invention discloses a coprecipitation reaction system for a precursor of a positive electrode material, which comprises the following components: a body for containing a precursor slurry; an input unit for inputting a precursor slurry into the body; the stirring assembly is arranged in the main body and is used for stirring the precursor slurry in the main body; the filtering component is arranged in the main body and is used for intercepting the precursor in the main body to obtain concentrated precursor slurry and filtering out filtered liquid; the back flushing device is used for carrying out back flushing regeneration on the filter assembly, and the primary back flushing quantity of the back flushing device is 1-2 times of the total volume of the filter assembly which is back flushed once. The invention fully ensures that the solution in the backflushing container is enough to thoroughly backflush the filter cake structures on the surfaces of all the filter components.

Description

Positive electrode material precursor coprecipitation reaction system

Technical Field

The invention relates to the technical field of precursor production, in particular to a coprecipitation reaction system for a positive electrode material precursor.

Background

The precursor slurry is the front end material of the positive electrode material and plays a decisive role in the performance of the positive electrode material. The production method of the positive electrode material precursor is generally as follows: preparing nickel sulfate (or nickel chloride), cobalt sulfate (or cobalt chloride) and manganese sulfate (or manganese chloride) into mixed salt solution with a certain molar concentration, preparing sodium hydroxide into alkali solution with a certain molar concentration, and using ammonia water with a certain concentration as a complexing agent. Adding the filtered mixed salt solution, alkali solution and complexing agent into a reaction kettle at a certain flow, controlling the stirring rate of the reaction kettle, and controlling the temperature and pH value of the reaction slurry to enable the salt and alkali to undergo a neutralization reaction to generate ternary precursor crystal nuclei and grow gradually, and filtering, washing and drying the reaction slurry after the granularity reaches a preset value to obtain the ternary precursor.

In order to improve the solid content of the precursor slurry and optimize the morphology of the precursor, concentration equipment which combines the filtering and concentration functions and the stirring functions into a whole is arranged on the market and is used for concentrating the ternary precursor after reaction in the reaction kettle, so that the enrichment and concentration of the precursor slurry are realized. The applicant found that during the enrichment and concentration of the precursor slurry, the precursor gradually adheres to the surface of the filter element, thereby forming a layer of filter cake structure on the surface of the filter element, and the filter cake structure seriously affects the filtration flux of the filter element, thereby reducing the production efficiency of the precursor. The technical means for solving the problem that the filter cake affects the filtering flux in the prior art is to perform backflushing on the filtering component through backflushing equipment, however, some backflushing structures in the prior art can easily cause the penetration and leakage of the filtering component in the concentration equipment, and some backflushing structures cannot realize the thorough backflushing of the filter element.

Disclosure of Invention

The applicant finds that the technical problems of unstable liquid level of the reaction kettle and unstable liquid level of the concentration equipment often occur in the production process in actual production research, and all the technical problems can lead to unstable product quality of the obtained positive electrode material precursor. Specifically: the sum of the total amount of slurry in the reaction vessel and the total amount of slurry in the concentration device determines the working volume of the whole coprecipitation reaction system, which determines the total residence time of the reaction materials and the concentration of the materials in the reaction vessel, and also affects the stirring flow field. If the liquid level in the reaction kettle and the concentration equipment is too low, the total volume of the paddles is smaller, so that the higher concentration and the higher concentration can influence the clear flux of the filtered liquid of the system, the shorter retention time can cause incomplete reaction, filtration and material waste, and if the liquid level is too low, the paddles can fail and influence the stirring effect; if the liquid level is too high, the total stirring power is increased, resulting in overload of stirring. Therefore, the invention also provides a cathode material precursor coprecipitation reaction device aiming at the problem, so as to solve the technical problems of unstable liquid level of a reaction kettle and unstable liquid level in the cathode material precursor coprecipitation reaction device in the prior art, and the quality of the obtained cathode precursor product is unstable.

In order to achieve the above object, the present invention provides a cathode material precursor coprecipitation reaction apparatus comprising

A tank for containing a precursor slurry;

The filter assembly is arranged in the tank body and is used for intercepting the precursor in the tank body to obtain concentrated precursor slurry and filtering out filtered liquid;

The stirring unit is arranged in the tank body and used for stirring the precursor slurry in the tank body;

the pump material unit is used for pumping the precursor slurry in the reaction kettle into the tank body;

the reflux unit is used for refluxing the precursor slurry in the tank body to the reaction kettle;

The discharging unit is used for discharging the filtered liquid out of the tank body;

the first liquid level control unit comprises a clear valve for regulating and controlling the discharge flow of the filtered liquid, and the clear valve is used for interlocking control with a first liquid level meter arranged on the reaction kettle;

The second liquid level control unit comprises a second liquid level gauge arranged on the tank body and a reflux valve for regulating and controlling the reflux amount of the concentrated precursor slurry, and the second liquid level gauge and the reflux valve are in interlocking control.

Further, the first liquid level meter and the purge valve are subjected to interlocking control in a PID control mode.

Further, go out clear unit including connect filter element filtrate liquid export to the outer play of jar and pigtail, set up the clear pump of going out on pigtail, go out clear valve setting in the play pigtail.

Further, the purge valve comprises a pressure gauge, a purge flow meter and a purge pneumatic ball valve which are arranged on the purge pipe.

Further, the second liquid level meter and the reflux valve are subjected to interlocking control in a PID control mode.

Further, the reflux unit comprises a reflux pipe for connecting the tank body and the reaction kettle, and the reflux valve is arranged on the reflux pipe.

Further, the reflux valve is an electric regulating valve.

Further, a reflux cut-off valve is arranged on the reflux pipe.

Further, the pump material unit includes the inlet pipe of connecting reation kettle and jar body, sets up charge pump, feeding flowmeter and the pneumatic ball valve of feeding on the inlet pipe.

A coprecipitation reaction system, comprising:

a reaction kettle for reacting reactants therein to generate precursor slurry;

The cathode material precursor coprecipitation reaction device comprises a tank body, a filtering component and a stirring unit, wherein the filtering component and the stirring unit are arranged in the tank body, the tank body is used for containing precursor slurry, and the filtering component is used for intercepting the precursor in the tank body to obtain concentrated precursor slurry and filtering out filtered liquid; the stirring unit is used for stirring the precursor slurry in the tank body;

The first liquid level control unit comprises a first liquid level meter and a clear valve, wherein the first liquid level meter is arranged on the reaction kettle, and the clear valve is used for regulating and controlling the discharge flow of the filtered liquid;

Therefore, the first liquid level control unit is used for controlling the purge valve and the first liquid level meter in an interlocking manner, namely the opening degree of the purge valve is correspondingly regulated according to the reading of the first liquid level control unit, so that the liquid level in the reaction kettle is controlled to be stable in the production process; and the second liquid level gauge and the reflux valve are controlled in an interlocking manner through the second liquid level control unit, namely the opening of the reflux valve is correspondingly regulated according to the reading of the second liquid level control unit, so that the liquid level in the tank body of the positive electrode material precursor coprecipitation reaction device is controlled to be stable in the production process. The method is characterized in that the amount of filtered liquid discharged from the tank body is controlled to be consistent with the amount of liquid fed into the reaction kettle, and the liquid level of ternary precursor slurry in the tank body is controlled to be stable, so that the total reaction residence time of the ternary precursor slurry, the concentration of materials in the reaction kettle, the stirring flow field and the system discharged amount are ensured, and the quality of the finally produced ternary precursor product of the positive electrode material is ensured to be stable.

The invention also provides a coprecipitation reaction device for the precursor of the positive electrode material, which is used for solving the problems of different particle sizes, broken filter components and damaged particle surfaces of precursor products caused by improper setting positions of stirring paddles in the prior art.

The applicant finds that the problem of uneven size of precursor product particles is caused by insufficient stirring of precursor slurry when the stirring blades and the filter assembly are arranged far away in practical production research; when stirring paddle and filter component set up too closely, stirring paddle can with the filter cake contact of filter component filter surface formation or the fluid that the stirring formed directly forms stronger effort to the filter component filter surface at the radial upper end of jar body, perhaps through the stronger effort indirect effect filter component filter surface to the filter cake formation on the filter component filter surface, lead to filter component fracture, precursor product particle surface is destroyed.

In order to achieve the above object, the present invention provides a cathode material precursor coprecipitation reaction apparatus, comprising:

A tank for containing a precursor slurry;

An input unit for inputting the precursor slurry into the tank;

The stirring assembly is arranged in the tank body and used for stirring the precursor slurry in the tank body;

the filtering component is circumferentially arranged in the tank body around the stirring component and is used for intercepting the precursor in the tank body to obtain concentrated precursor slurry and filtering out filtered liquid;

The end part of the stirring blade of the stirring assembly in the radial direction of the tank body circumferentially forms a first cylindrical surface during stirring, the position Zhou Xianglian closest to the stirring blade on all the filtering assemblies is a second cylindrical surface, and the ratio of the distance between the first cylindrical surface in the radial direction and the second cylindrical surface to the inner diameter of the tank body is 5% -15%.

Further, the ratio of the distance between the first cylindrical surface and the second cylindrical surface in the radial direction to the inner diameter of the can body is 6% -8%.

Further, the distance between the first cylindrical surface and the second cylindrical surface in the radial direction is 15-25mm.

Further, a distance between the first cylindrical surface and the second cylindrical surface in the radial direction is 100-150mm.

Further, the ratio of the width of the gap to the inner diameter of the can is 6% -8%.

Further, the stirring linear speed of the stirring assembly is 5-10m/s.

Further, the stirring linear speed of the stirring assembly is 7-8m/s.

Further, the filter component is a metal filter element.

Further, the filter component comprises a filter liquid pipe fixed in the tank body and a filter component fixed on the filter liquid pipe at intervals, the filter liquid pipe comprises an outer ring pipe and an inner ring pipe which are radially arranged from outside to inside along the tank body, the outer ring pipe and the inner ring pipe are externally connected with a clear liquid system through a clear liquid outlet pipe, and the outer ring pipe and the inner ring pipe are sealing pipes.

Further, the outer ring pipe is externally connected with a clear liquid discharging system through a clear liquid discharging pipe, and the inner ring pipe is connected with and communicated with the clear liquid discharging pipe through an elbow pipe.

Further, the outer ring pipe and the inner ring pipe are independently arranged, and the inner ring pipe and the outer ring pipe are respectively externally connected with a cleaning liquid system through independent cleaning liquid outlet pipes.

Further, the inner ring pipe is disposed at a position higher than the outer ring pipe.

Therefore, the co-precipitation reaction equipment for the precursor of the positive electrode material solves the problems that the particle sizes of the precursor products are different, the filter assembly is broken and the particle surfaces are damaged due to improper arrangement of the stirring blades and the filter assembly, and the particle sizes of the precursor products are uneven; when stirring paddle and filter component set up too closely, stirring paddle can with the filter cake contact of filter core surface formation or the fluid that the stirring formed forms the filter core surface stronger effort, lead to filter component fracture, precursor product particle surface destroyed.

The applicant discovers when installing the filtration subassembly of concentrator that filtration subassembly's mounting structure has directly influenced concentrator's filtration flux and the output flow of gained straining the clear liquid, and traditional filtration subassembly is the installation of individual layer filter core, and its mounting means leads to filtering flux less, the output of straining the liquid is little, directly influences the play clear volume of whole precursor production system, leads to precursor production efficiency to reduce.

The invention also provides a cathode material precursor coprecipitation reaction device, which is used for solving the technical problem of reduced production efficiency of the cathode material precursor coprecipitation reaction device caused by the installation structure of the filter assembly in the prior art.

In order to achieve the above object, according to one aspect of the present invention, there is provided a positive electrode material precursor coprecipitation reaction apparatus comprising:

a tank for containing a ternary precursor slurry;

an input unit for inputting the ternary precursor slurry into the tank;

the stirring assembly is arranged in the tank body and is used for stirring ternary precursor slurry in the tank body,

The filtering component comprises a filtering liquid pipe fixed in the tank body and a filtering core fixed on the filtering liquid pipe at intervals, the filtering liquid pipe comprises an outer ring pipe and an inner ring pipe which are arranged from outside to inside along the radial direction of the tank body, the outer ring pipe and the inner ring pipe are respectively externally connected with a cleaning liquid system through a cleaning liquid outlet pipe, and the outer ring pipe and the inner ring pipe are respectively sealing pipes;

the installation position of the filter element on the outer ring pipe and the installation position of the filter component on the inner ring pipe are arranged in a staggered mode.

Therefore, the cathode material precursor coprecipitation reaction device provided by the invention has the advantages that the filter assemblies are circumferentially distributed in the tank body by arranging the outer ring pipe and the inner ring pipe, the installation positions of the filter assemblies are increased, more filter assemblies are allowed to be installed, the filtration flux and the cleaning output of the filter assemblies are greatly increased, the filter elements on the inner ring and the outer ring are selected to be installed in a staggered manner on the installation positions of the filter elements, and the staggered installation benefits are that: the filter element is conveniently installed inside and outside, and the inner ring and the outer ring cannot mutually block and interfere when the filter element is installed; secondly do benefit to the stirring subassembly when stirring, the thick liquids fluid in the jar body contacts each filter core, has guaranteed the filtration flux on the one hand, and on the other hand has guaranteed that thick liquids fluid erodees the filter cake that each filter core surface formed at the flow in-process, prevents that the filter cake from blockking each other because of the filter core and leading to quick deposit, and then does benefit to the assurance of filtration flux, has guaranteed the filtration flux and the output flow of filter liquor of whole positive electrode material precursor coprecipitation reaction equipment from this.

The invention provides the following different connection modes of a filtering liquid pipe and a cleaning liquid outlet pipe.

Further, the outer ring pipe is externally connected with a clear liquid system through a clear liquid outlet pipe, and the inner ring pipe and the outer ring pipe are connected and conducted through a horizontal straight pipe. The two ends of the horizontal straight pipe are required to be welded to the inner ring pipe and the outer ring pipe respectively through T-shaped welding.

Further, the outer ring pipe is externally connected with a clear liquid discharging system through a clear liquid discharging pipe, and the inner ring pipe is connected with and communicated with the clear liquid discharging pipe through an elbow pipe. Compared with the T-shaped welding at the two ends of the horizontal straight pipe, the connecting mode is quicker and simpler.

Further, the outer ring pipe and the inner ring pipe are independently arranged, and the inner ring pipe and the outer ring pipe are respectively externally connected with a cleaning liquid system through independent cleaning liquid outlet pipes. Compared with the T-shaped welding at the two ends of the horizontal straight pipe, the connecting mode is quicker, more convenient and simpler, and the independent liquid outlet pipe is more convenient to install.

Further, one end part of the inner ring pipe is longer than the corresponding end part of the outer ring pipe by one section, the clear liquid outlet pipe of the inner ring is connected and communicated with the end part of the inner ring pipe, and the clear liquid outlet pipe of the outer ring is connected and communicated with the end part of the outer ring pipe. Because the horizontal straight pipe, the inner ring pipe and the outer ring pipe respectively form a T shape, full penetration welding seams are needed to be carried out at the joint, and therefore, compared with the T-shaped welding at the two ends of the horizontal straight pipe, the connecting mode is quicker, simpler and more convenient, and the independent liquid outlet pipe is more convenient to install.

Further, the inner ring pipe is disposed at a position higher than the outer ring pipe. The position connection mode of the inner ring pipe and the outer ring pipe is compared with the condition that the inner ring pipe and the outer ring pipe are at the same height, the filter assembly is more convenient to detach and install, and the filter assembly is convenient to install and overhaul.

Further, the clear liquid outlet pipe is a pipeline which is vertically downwards arranged.

Further, a fixing piece is radially arranged in the tank body, and the inner ring pipe and the outer ring pipe are arranged on the fixing piece from inside to outside.

Further, the fixing piece is a fixing rod, and two ends of the inner ring pipe and the outer ring pipe are respectively connected with the fixing rod through welding; or the two ends of the inner ring pipe and the outer ring pipe are fixed on the fixed rod through hoop members.

Further, the inner ring pipe and the outer ring pipe are arc pipes.

Further, the filter assembly comprises four filter units, and the central angle of the arc-shaped pipe is 75-80 degrees.

The technical means for solving the problem that the filter cake affects the filtration flux in the prior art is to perform backflushing on the filter component through backflushing equipment, however, some backflushing structures in the prior art can easily cause damage to the filter component in the concentration equipment, and some backflushing structures cannot realize thorough backflushing of the filter element.

The invention also provides a coprecipitation reaction system for the positive electrode material precursor, which is used for solving the problems that some backflushing structures in the prior art can easily cause the penetration and leakage of a filter assembly in a concentration device, and other backflushing structures cannot realize the thorough backflushing of a filter element.

In order to achieve the above object, according to the present invention, there is provided a cathode material precursor coprecipitation reaction system including:

A tank for containing a precursor slurry;

An input unit for inputting the precursor slurry into the tank;

the filtering component is arranged in the tank body and is used for intercepting the precursor in the tank body to obtain concentrated precursor slurry and filtering out filtered liquid;

the back flushing device is used for carrying out back flushing regeneration on the filter assembly, and the primary back flushing quantity of the back flushing device is 1-2 times of the total volume of the filter assembly which is back flushed once.

The applicant found in the study that the backflushing of the filter assemblies by groups effectively ensures the backflushing effect,

Further, at least two groups of filter components are arranged in the tank body, and the primary recoil quantity of the recoil device is 1-2 times of the total volume of one group of filter components.

Further, the recoil apparatus includes:

The backflushing container is used for containing backflushing gas/backflushing liquid, and an outlet of the backflushing container is connected with a filtered liquid outlet of the filtering component to be regenerated;

an inlet control assembly for controlling the input of regeneration gas into the backwash vessel;

The liquid inlet control assembly is used for controlling the regenerated liquid to be input into the backflushing container;

And the backflushing control assembly is used for controlling the regeneration gas/regeneration liquid to be output from the backflushing container through an outlet of the backflushing container.

Further, the recoil control assembly comprises a recoil pipe connected with the liquid outlet of the recoil container and a pneumatic ball valve arranged on the recoil pipe.

Further, the back flushing pipe is branched out of the back flushing side pipe corresponding to each group of filter components, each back flushing side pipe is provided with a manual ball valve, and each group of filter components is connected with the back flushing container through the back flushing side pipe.

Further, each recoil bypass pipe is provided with a sight glass.

Further, the air inlet control assembly comprises an air inlet pipe connected with an air source, and a pneumatic ball valve, a pressure gauge and a stop valve which are arranged on the air inlet pipe.

Further, the liquid inlet control assembly comprises a liquid inlet pipe connected with the regeneration liquid source and a manual ball valve arranged on the liquid inlet pipe.

Further, the volume of the backflushing container is 1.5-2.5 times the volume of the filter assembly that is backflushed at one time.

Further, the device also comprises a clean-out component and a pure water control component, wherein the clean-out component is used for discharging the filtered liquid, the pure water control component is respectively connected with the clean-out component and the backflushing device, and the pure water control component is used for controlling pure water to enter the clean-out component and the backflushing device.

Thus, the ratio of the volume of the backflushing vessel to the volume of the filter elements in the filter element regeneration system of the present invention substantially ensures that the solution in the backflushing vessel is sufficient to thoroughly backflush the filter cake structure across all filter element surfaces.

The invention is further described below with reference to the drawings and detailed description. Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The accompanying drawings, which form a part hereof, are shown by way of illustration and not of limitation, and in which are shown by way of illustration and description of the invention. In the drawings:

FIG. 1 is a schematic diagram of a precursor production system according to the present invention.

FIG. 2 is a top view of one of the filter assembly mounting structures of the present invention.

FIG. 3 is a top view of a second embodiment of a filter assembly mounting structure according to the present invention.

Fig. 4 is a schematic structural diagram of a first connection mode of a clear liquid filtering pipe and a clear liquid outlet pipe in the invention.

FIG. 5 is a schematic diagram of a second embodiment of a connection between a filtered fluid pipe and a clean fluid outlet pipe.

Fig. 6 is a schematic structural diagram of a third connection mode of the clear liquid filtering pipe and the clear liquid outlet pipe in the invention.

Fig. 7 is a schematic structural diagram of a fourth connection mode of a filtering liquid pipe and a clear liquid outlet pipe in the invention.

Fig. 8 is a topography of ternary precursor products obtained in examples one through sixteen of the present invention.

FIG. 9 is a schematic diagram of the relationship between the stirring assembly and the filtering assembly according to the present invention.

FIG. 10 is a schematic illustration of the attachment of a filter cake to the filter surface of a filter assembly proximate to a stirring blade in accordance with the present invention.

FIG. 11 is a schematic illustration of the present invention with the mounting position of the filter cartridge on the outer ring tube and the mounting position of the filter assembly on the inner ring tube offset.

Detailed Description

The present invention will now be described more fully hereinafter with reference to the accompanying drawings. Those of ordinary skill in the art will be able to implement the invention based on these descriptions. Before describing the present invention with reference to the accompanying drawings, it should be noted in particular that:

The technical solutions and technical features provided in the sections including the following description in the present invention may be combined with each other without conflict.

In addition, the embodiments of the present invention referred to in the following description are typically only some, but not all, embodiments of the present invention. Therefore, all other embodiments, which can be made by one of ordinary skill in the art without undue burden, are intended to be within the scope of the present invention, based on the embodiments of the present invention.

Terms and units in relation to the present invention. The terms "comprising," "having," and any variations thereof in the description and claims of the invention and in the relevant sections are intended to cover a non-exclusive inclusion.

The invention relates to a coprecipitation reaction device for a precursor of a positive electrode material, which comprises

A tank 21 for containing a precursor slurry;

A filter assembly 23 installed in the tank 21 for intercepting the precursor in the tank 21 to obtain concentrated precursor slurry and filtering out a filtered liquid;

a stirring unit 22 installed in the tank 21 for stirring the precursor slurry in the tank 21;

A pumping unit for pumping the precursor slurry in the reaction kettle 1 into the tank 21;

a reflux unit for refluxing the precursor slurry in the tank 21 to the reaction kettle 1;

a discharging unit for discharging the filtered liquid to the outside of the tank body 21;

The first liquid level control unit comprises a clear valve for regulating and controlling the discharge flow of the filtered liquid, and the clear valve is used for interlocking control with a first liquid level meter 31 arranged on the reaction kettle;

the second liquid level control unit comprises a second liquid level meter 51 arranged on the tank body 21 and a reflux valve 52 for regulating and controlling the reflux amount of the concentrated precursor slurry, and the second liquid level meter 51 and the reflux valve 52 are controlled in an interlocking way.

The first liquid level meter 31 and the purge valve are controlled in an interlocking manner by a PID control mode.

The cleaning unit comprises a cleaning pipe 41 for connecting the filtered liquid outlet of the filter assembly 23 to the outside of the tank body 21, and a cleaning pump 42 arranged on the cleaning pipe 41, and the cleaning valve is arranged on the cleaning pipe 41.

The purge valve comprises a pressure gauge 322, a purge flow meter 323 and a purge pneumatic ball valve 321 which are arranged on the purge pipe 41.

The second liquid level gauge 51 and the reflux valve 52 are controlled in an interlocking manner by a PID control mode.

The reflux unit comprises a reflux pipe for connecting the tank body 21 and the reaction kettle 1, and the reflux valve 52 is arranged on the reflux pipe.

The return valve 52 is an electrically operated valve.

The reflux pipe is also provided with a reflux cut-off valve 7.

The pump material unit includes a feeding pipe 61 connecting the reaction kettle 1 and the tank body 21, a feeding pump 62 arranged on the feeding pipe 61, a feeding flowmeter 63 and a feeding pneumatic ball valve 64.

A coprecipitation reaction system, comprising:

a reaction kettle 1 for reacting reactants therein to generate precursor slurry;

The cathode material precursor coprecipitation reaction device 2 comprises a tank body 21, a filter assembly 23 and a stirring unit 22, wherein the filter assembly 23 and the stirring unit 22 are arranged in the tank body 21, the tank body 21 is used for containing precursor slurry, and the filter assembly 23 is used for intercepting the precursor in the tank body 21 to obtain concentrated precursor slurry and filtering out filtered liquid; the stirring unit 22 is used for stirring the precursor slurry in the tank body 21;

The first liquid level control unit comprises a first liquid level meter 31 arranged on the reaction kettle 1 and a clear valve for regulating and controlling the discharge flow of the filtered liquid, wherein the first liquid level meter 31 and the clear valve are controlled in an interlocking way;

The invention discloses a coprecipitation reaction device for a precursor of a positive electrode material, which comprises:

A tank 21 for containing a precursor slurry;

an input unit for inputting the precursor slurry into the tank 21;

A stirring assembly 22 disposed in the tank 21 for stirring the precursor slurry in the tank 21;

the filtering component 23 is circumferentially arranged in the tank body 21 around the stirring component 22 and is used for intercepting the precursor in the tank body 21 to obtain concentrated precursor slurry and filtering out filtered liquid;

the positions of the stirring blades of the stirring assembly 22 at the end part of the tank body 21 in the radial direction during stirring are all located on a first virtual cylinder surface, the positions of the closest stirring blades on the filter surfaces of all the filter assemblies are all located on a second virtual cylinder surface, and the ratio of the distance between the first virtual cylinder surface and the second virtual cylinder surface in the radial direction of the tank body 21 to the inner diameter of the tank body 21 is 5% -15%.

The ratio of the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction to the inner diameter of the can 21 is 6% -8%.

The volume of the tank 21 is 50-100L, and the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction is 20-40mm.

The volume of the tank body 21 is 0.6-8m ³, and the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction is 100-150mm.

The stirring line speed of the stirring assembly 22 is 5-10m/s.

The stirring line speed of the stirring assembly 22 is 7-8m/s.

The filter assembly 23 comprises a filtering liquid pipe fixed in the tank body 21 and a filtering filter element 235 fixed on the filtering liquid pipe at intervals, the filtering liquid pipe comprises an outer ring pipe 231 and an inner ring pipe 232 which are radially distributed from outside to inside along the tank body 21, the outer ring pipe 231 and the inner ring pipe 232 are externally connected with a clear liquid outlet system through the clear liquid outlet pipe 233, and the outer ring pipe 231 and the inner ring pipe 232 are sealing pipes.

The outer ring pipe 231 is externally connected with a clear liquid outlet system through a clear liquid outlet pipe 233, and the inner ring pipe 232 is connected and communicated with the clear liquid outlet pipe 233 through a bent pipe 236.

The outer ring pipe 231 and the inner ring pipe 232 are independently arranged, and the inner ring pipe 232 and the outer ring pipe 231 are respectively externally connected with a clear liquid outlet system through independent clear liquid outlet pipes 233.

The inner ring pipe 232 is disposed at a position higher than the outer ring pipe 231.

A tank 21 for containing a precursor slurry;

an input unit for inputting the precursor slurry into the tank 21;

The filtering component 23 comprises a plurality of filtering units which are circumferentially distributed in the tank body 21 around the stirring component 22 and are used for intercepting the precursor in the tank body 21 to obtain concentrated precursor slurry and filtering out filtered liquid;

The filtering assembly 23 comprises a filtering liquid pipe fixed in the tank body 21 and a filtering filter element 235 fixed on the filtering liquid pipe at intervals, the filtering liquid pipe comprises an outer ring pipe 231 and an inner ring pipe 232 which are arranged from outside to inside along the radial direction of the tank body 21, the outer ring pipe 231 and the inner ring pipe 232 are externally connected with a clear liquid outlet system through the clear liquid outlet pipe 233, and the outer ring pipe 231 and the inner ring pipe 232 are sealed pipes;

The installation position of the filter element 235 on the outer ring pipe 231 is staggered with the installation position of the filter element 235 of the inner ring pipe 232.

The outer ring pipe 231 is externally connected with a clear liquid outlet system through a clear liquid outlet pipe 233, and the inner ring pipe 232 and the outer ring pipe 231 are connected and communicated through a horizontal straight pipe 234.

One end of the inner ring pipe 232 is longer than the corresponding end of the outer ring pipe 231, the purge pipe 233 of the inner ring is connected to and conducted with the end of the inner ring pipe 232, and the purge pipe 233 of the outer ring is connected to and conducted with the end of the outer ring pipe 231.

The purge tube 233 is a vertically downward pipe.

The tank body 21 is radially provided with fixing pieces, and the inner ring pipe 232 and the outer ring pipe 231 are arranged on the fixing pieces from inside to outside.

The fixing piece is a fixing rod 121, and two ends of the inner ring pipe 232 and the outer ring pipe 231 are respectively connected with the fixing rod 121 through welding; or both ends of the inner ring pipe 232 and the outer ring pipe 231 are fixed to the fixing rod 121 by the anchor members 122.

The inner ring pipe 232 and the outer ring pipe 231 are arc-shaped pipes.

The filter assembly 23 comprises four filter units, and the central angle of the arc-shaped pipe is 75-80 degrees.

A cathode material precursor co-precipitation reaction system comprising:

A tank 21 for containing a precursor slurry;

an input unit for inputting the precursor slurry into the tank 21;

A filter assembly 23 disposed in the tank 21 for intercepting the precursor in the tank 21 to obtain concentrated precursor slurry and filtering out a filtered liquid;

And the back flushing device is used for carrying out back flushing regeneration on the filter assembly 23, and the primary back flushing quantity of the back flushing device is 1-2 times of the total volume of the filter assembly 23 which is back flushed once.

At least two groups of filter components 23 are arranged in the tank body 21, and the primary recoil quantity of the recoil device is 1-2 times of the total volume of one group of filter components 23.

The recoil device includes:

A backflushing vessel 8 for containing backflushing gas/backflushing liquid, the outlet of the backflushing vessel 8 being connected to the filtered liquid outlet of the filter assembly 23 to be regenerated;

An intake control assembly for controlling the input of regeneration gas into the backwash vessel 8;

a liquid inlet control component for controlling the regenerated liquid to be input into the backflushing container 8;

A back flushing control unit for controlling the regeneration gas/regeneration liquid to be outputted from the back flushing container 8 through the outlet of the back flushing container 8.

The recoil control assembly includes a recoil tube connected to the liquid outlet of the recoil vessel 8 and a pneumatic ball valve 112 disposed on the recoil tube.

The back flushing pipe is branched out of a back flushing bypass pipe 111 corresponding to each group of filter components 23, a manual ball valve 1022 is arranged on each back flushing bypass pipe 111, and each group of filter components 23 is connected with the back flushing container 8 through the back flushing bypass pipe 111.

A sight glass 113 is provided on each recoil bypass tube 111.

The air inlet control assembly comprises an air inlet pipe 91 connected with an air source, a pneumatic ball valve 92, a pressure gauge 93 and a stop valve 94 which are arranged on the air inlet pipe 91.

The liquid inlet control assembly comprises a liquid inlet pipe 101 connected with a regeneration liquid source and a manual ball valve 102 arranged on the liquid inlet pipe 101.

The volume of the backflushing vessel 8 is 1.5-2.5 times the volume of the filter assembly 23 that is backflushed at a time.

The device also comprises a clean-out component and a pure water control component, wherein the clean-out component is used for discharging the filtered liquid, the pure water control component is respectively connected with the clean-out component and the backflushing device, and the pure water control component is used for controlling pure water to enter the clean-out component and the backflushing device.

The positive electrode material precursor coprecipitation reaction device and the positive electrode material precursor coprecipitation reaction device are suitable for precursor production, and are particularly suitable for application in ternary precursor production.

As shown in FIG. 1, the coprecipitation reaction system of the present invention includes the following structural modules: comprises a reaction kettle 1 and a positive electrode material precursor coprecipitation reaction device 2; a pumping unit for pumping the ternary precursor slurry in the reaction kettle 1 into the tank 21; the reflux unit is used for refluxing concentrated ternary precursor slurry obtained by the action of the filtering component 23 and the stirring unit 22 in the tank body 21 to the reaction kettle 1; a discharging unit for discharging the filtered liquid to the outside of the tank body 21; the liquid inlet and outlet control unit is used for controlling the clear liquid outlet of the tank body 21 to be consistent with the liquid inlet of the reaction kettle 1; a tank body liquid level control unit for controlling the liquid level of the ternary precursor slurry in the tank body 21 to be kept stable; a filter assembly regeneration system.

Wherein the positive electrode material precursor coprecipitation reaction apparatus 2 includes: a tank 21 for holding a ternary precursor slurry; an input unit for inputting the ternary precursor slurry into the tank 21; a stirring assembly 22, disposed in the tank 21, for stirring the ternary precursor slurry in the tank 21; the filtering component 23 comprises a plurality of filtering units which are circumferentially distributed in the tank body 21 around the stirring component 22 and are used for intercepting the precursor in the tank body 21 to obtain concentrated ternary precursor slurry and filtering out filtered liquid.

The invention is further described below with respect to improvements made to the technical problem of unstable liquid level in the reaction kettle and the concentration equipment in the co-precipitation system of the precursor of the positive electrode material.

As shown in FIG. 1, the apparatus for coprecipitation reaction of precursors of positive electrode material of the present invention comprises

A tank 21 for containing a precursor slurry; a filter assembly 23 installed in the tank 21 for intercepting the precursor in the tank 21 to obtain concentrated precursor slurry and filtering out a filtered liquid; a stirring unit 22 installed in the tank 21 for stirring the precursor slurry in the tank 21; a pumping unit for pumping the precursor slurry in the reaction kettle 1 into the tank 21; a reflux unit for refluxing the precursor slurry in the tank 21 to the reaction kettle 1; a discharging unit for discharging the filtered liquid to the outside of the tank body 21; the first liquid level control unit comprises a clear valve for regulating and controlling the discharge flow of the filtered liquid, and the clear valve is used for interlocking control with a first liquid level meter 31 arranged on the reaction kettle; the second liquid level control unit comprises a second liquid level meter 51 arranged on the tank body 21 and a reflux valve 52 for regulating and controlling the reflux amount of the concentrated precursor slurry, and the second liquid level meter 51 and the reflux valve 52 are controlled in an interlocking way. The first liquid level meter 31 and the purge valve are controlled in an interlocking manner by a PID control mode. The cleaning unit comprises a cleaning pipe 41 for connecting the filtered liquid outlet of the filter assembly 23 to the outside of the tank body 21, and a cleaning pump 42 arranged on the cleaning pipe 41, and the cleaning valve is arranged on the cleaning pipe 41. The purge valve comprises a pressure gauge 322, a purge flow meter 323 and a purge pneumatic ball valve 321 which are arranged on the purge pipe 41. The second liquid level gauge 51 and the reflux valve 52 are controlled in an interlocking manner by a PID control mode. The reflux unit comprises a reflux pipe for connecting the tank body 21 and the reaction kettle 1, and the reflux valve 52 is arranged on the reflux pipe. The return valve 52 is an electrically operated valve. The reflux pipe is also provided with a reflux cut-off valve 7. The pump material unit includes a feeding pipe 61 connecting the reaction kettle 1 and the tank body 21, a feeding pump 62 arranged on the feeding pipe 61, a feeding flowmeter 63 and a feeding pneumatic ball valve 64.

A coprecipitation reaction system, comprising: a reaction kettle 1 for reacting reactants therein to generate precursor slurry; the cathode material precursor coprecipitation reaction device 2 comprises a tank body 21, a filter assembly 23 and a stirring unit 22, wherein the filter assembly 23 and the stirring unit 22 are arranged in the tank body 21, the tank body 21 is used for containing precursor slurry, and the filter assembly 23 is used for intercepting the precursor in the tank body 21 to obtain concentrated precursor slurry and filtering out filtered liquid; the stirring unit 22 is used for stirring the precursor slurry in the tank body 21; a pumping unit for pumping the precursor slurry in the reaction kettle 1 into the tank 21; a reflux unit for refluxing the precursor slurry in the tank 21 to the reaction kettle 1; a discharging unit for discharging the filtered liquid to the outside of the tank body 21; the first liquid level control unit comprises a first liquid level meter 31 arranged on the reaction kettle 1 and a clear valve for regulating and controlling the discharge flow of the filtered liquid, wherein the first liquid level meter 31 and the clear valve are controlled in an interlocking way; the second liquid level control unit comprises a second liquid level meter 51 arranged on the tank body 21 and a reflux valve 52 for regulating and controlling the reflux amount of the concentrated precursor slurry, and the second liquid level meter 51 and the reflux valve 52 are controlled in an interlocking way.

The work flow of the coprecipitation reaction system under the improvement is as follows: under the condition that the feeding flow of the reaction kettle 1 is fixed, a first liquid level meter 31 on the reaction kettle 1 monitors the liquid level change of the reaction kettle 1 and sends a liquid level change signal to a controller controlled by a PID control mode, when the liquid level of the first liquid level meter 31 is monitored to be higher than a liquid level set threshold value, the stirring total power is increased if no adjustment is performed at the moment, stirring overload is caused, and therefore the valve opening of a clean pneumatic ball valve 321 is increased through PID control at the moment; when the liquid level of the first liquid level meter 31 is monitored to be lower than the liquid level setting threshold value, the total volume of the paddle materials is smaller, so that the higher concentration and the higher concentration can influence the clear liquid output of the system, the shorter concentration and the higher concentration can cause incomplete reaction, the liquid level is too low, if the liquid level is lower than the upper paddle, the upper paddle can be invalid, and the stirring effect is influenced, so that the valve opening of the clear pneumatic ball valve 321 is reduced through PID control, and the liquid level stability of the reaction kettle 1 is ensured. Under the condition that the feeding flow of the tank body 21 is fixed, the second liquid level meter 51 on the tank body 21 monitors the liquid level in the tank body 21 in real time, when the second liquid level meter 51 monitors that the liquid level of the tank body 21 is higher than a threshold value, the stirring total power is increased, the stirring overload problem is caused, the filtering component is damaged, particularly the filter element component made of plastic materials is broken, the material waste problem is caused, and therefore the opening of the reflux valve 52 is increased through PID control; when the second level gauge 51 monitors that the liquid level of the tank 21 is above the threshold, the flux of the filter assembly cannot reach the expected value, and if the flux is lower than the upper blade, the upper blade is disabled, the stirring effect is affected, and at the moment, the opening degree of the reflux valve 52 needs to be reduced through PID control, so that the liquid level in the tank 21 is stable.

The invention ensures the stable quality of the finally produced product by controlling the clear amount of the filtered liquid of the tank body to be consistent with the liquid inlet amount of the reaction kettle and controlling the liquid level of the ternary precursor slurry in the tank body to be stable, thereby ensuring the reaction residence time of the ternary precursor slurry in the reaction kettle and the filtration pressure difference of the filter assembly in the positive electrode material precursor coprecipitation reaction equipment. The obtained filtrate can be used as ingredients of other coprecipitation reaction systems.

The following is a further explanation of the improvement of the present invention in the structural relationship of the stirring member and the filtering member of the cathode material precursor coprecipitation reaction apparatus.

As shown in fig. 9, the cathode material precursor coprecipitation reaction apparatus of the present invention includes: a tank 21 for containing a precursor slurry; an input unit for inputting the precursor slurry into the tank 21; a stirring assembly 22 disposed in the tank 21 for stirring the precursor slurry in the tank 21; the filtering component 23 is circumferentially arranged in the tank body 21 around the stirring component 22 and is used for intercepting the precursor in the tank body 21 to obtain concentrated precursor slurry and filtering out filtered liquid; the positions of the stirring blades of the stirring assembly 22 at the end part of the tank body 21 in the radial direction during stirring are all located on a first virtual cylinder surface, the positions of the closest stirring blades on the filtering surfaces of all the filtering assemblies are all located on a second virtual cylinder surface, and the ratio of the distance d between the first virtual cylinder surface and the second virtual cylinder surface in the radial direction of the tank body 21 to the inner diameter of the tank body 21 is 5% -15%. The ratio of the distance d between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction to the inner diameter of the can 21 is 6% -8%. The volume of the tank 21 is 50-100L, and the distance d between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction is 20-40mm. The volume of the tank body 21 is 0.6-8m ³, and the distance d between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction is 100-150mm. The stirring line speed of the stirring assembly 22 is 5-10m/s. The stirring line speed of the stirring assembly 22 is 7-8m/s. The filter assembly 23 comprises a filtering liquid pipe fixed in the tank body 21 and a filtering filter element 235 fixed on the filtering liquid pipe at intervals, the filtering liquid pipe comprises an outer ring pipe 231 and an inner ring pipe 232 which are radially distributed from outside to inside along the tank body 21, the outer ring pipe 231 and the inner ring pipe 232 are externally connected with a clear liquid outlet system through the clear liquid outlet pipe 233, and the outer ring pipe 231 and the inner ring pipe 232 are sealing pipes. The outer ring pipe 231 is externally connected with a clear liquid outlet system through a clear liquid outlet pipe 233, and the inner ring pipe 232 is connected and communicated with the clear liquid outlet pipe 233 through a bent pipe 236. The outer ring pipe 231 and the inner ring pipe 232 are independently arranged, and the inner ring pipe 232 and the outer ring pipe 231 are respectively externally connected with a clear liquid outlet system through independent clear liquid outlet pipes 233. The inner ring pipe 232 is disposed at a position higher than the outer ring pipe 231.

The reaction of the precursor is a salt-alkali neutralization reaction, nickel sulfate (or nickel chloride), cobalt sulfate (or cobalt chloride) and manganese sulfate (or manganese chloride) are prepared into a mixed salt solution with a certain molar concentration, sodium hydroxide is prepared into an alkali solution with a certain molar concentration, and ammonia water with a certain concentration is used as a complexing agent. All prepared solutions are filtered, and solid impurities are removed before the solution enters the next link. Adding the filtered salt solution, alkali solution and complexing agent into a reaction kettle at a certain flow, controlling the stirring rate of the reaction kettle, and controlling the temperature and pH value of the reaction slurry to enable the salt and alkali to undergo a neutralization reaction to generate ternary precursor crystal nuclei and grow gradually, and filtering, washing and drying the reaction slurry after the granularity reaches a preset value to obtain the ternary precursor. In the process, the sodium hydroxide and the ammonia water are mixed and then added into the reaction kettle at the same time by a company, so that the production line is simplified. If the doped ternary precursor is required to be prepared, the doped solution can be added into a reaction kettle in the reaction process, and the doped ternary precursor is obtained after the reaction is completed. The following examples were carried out with the same reaction batch composition, reaction batch concentration, reaction temperature, and pH at each stage.

Embodiment one: the ratio of the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction of the tank 21 to the inner diameter of the tank 21 is 5%, and the stirring linear velocity of the stirring unit 22 is 5m/s. Cathode material precursor coprecipitation reaction equipment in the first embodiment, the particle size of the ternary precursor product obtained by the cathode material precursor coprecipitation reaction equipment in the application process of producing the ternary precursor by the actual cathode material precursor coprecipitation reaction equipment is uniform, and the surface of the particle is not damaged.

Embodiment two: the ratio of the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction of the tank 21 to the inner diameter of the tank 21 was 10%, and the stirring linear velocity of the stirring unit 22 was 3m/s. In the second embodiment, the particle size of the ternary precursor product obtained by the positive electrode material precursor coprecipitation reaction device in the application process of producing the ternary precursor by the actual positive electrode material precursor coprecipitation reaction device is uniform, and the surface of the particle is not damaged.

Embodiment III: the ratio of the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction of the tank 21 to the inner diameter of the tank 21 is 15%, and the stirring linear velocity of the stirring unit 22 is 8m/s. The three-component precursor product obtained by the positive electrode material precursor coprecipitation reaction device in the application process of producing the three-component precursor by the actual positive electrode material precursor coprecipitation reaction device has uniform particle size and no damage on the particle surface.

Embodiment four: the ratio of the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction of the tank 21 to the inner diameter of the tank 21 is 6%, and the stirring linear velocity of the stirring unit 22 is 7m/s. In the fourth embodiment, the particle size of the ternary precursor product obtained by the positive electrode material precursor coprecipitation reaction device in the application process of producing the ternary precursor by the actual positive electrode material precursor coprecipitation reaction device is uniform, and the surface of the particle is not damaged.

Fifth embodiment: the ratio of the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction of the tank 21 to the inner diameter of the tank 21 is 7%, and the stirring linear velocity of the stirring unit 22 is 7.5m/s. In the fifth embodiment, the particle size of the ternary precursor product obtained by the positive electrode material precursor coprecipitation reaction device in the application process of producing the ternary precursor by the actual positive electrode material precursor coprecipitation reaction device is uniform, and the surface of the particle is not damaged.

Example six: the ratio of the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction of the tank 21 to the inner diameter of the tank 21 is 8%, and the stirring linear velocity of the stirring unit 22 is 8m/s. In the sixth embodiment, the particle size of the ternary precursor product obtained by the positive electrode material precursor coprecipitation reaction device in the application process of producing the ternary precursor by the actual positive electrode material precursor coprecipitation reaction device is uniform, and the surface of the particle is not damaged.

Embodiment seven: the ratio of the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction of the tank 21 to the inner diameter of the tank 21 is 6%, and the stirring linear velocity of the stirring unit 22 is 7m/s. In the seventh embodiment, the particle size of the ternary precursor product obtained by the positive electrode material precursor coprecipitation reaction device in the application process of producing the ternary precursor by the actual positive electrode material precursor coprecipitation reaction device is uniform, and the surface of the particle is not damaged.

Example eight: the ratio of the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction of the tank 21 to the inner diameter of the tank 21 is 7%, and the stirring linear velocity of the stirring unit 22 is 7.5m/s. The ternary precursor product obtained by the positive electrode material precursor coprecipitation reaction device in the application process of producing the ternary precursor by the actual positive electrode material precursor coprecipitation reaction device has uniform particle size and no damage on the particle surface.

Example nine: the ratio of the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction of the tank 21 to the inner diameter of the tank 21 is 8%, and the stirring linear velocity of the stirring unit 22 is 8m/s. The ternary precursor product obtained by the positive electrode material precursor coprecipitation reaction device in the application process of producing the ternary precursor by the actual positive electrode material precursor coprecipitation reaction device has uniform particle size and no damage on the particle surface.

Example eleven: the volume of the tank 21 is 50L, and the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction is 20mm. The stirring line speed of the stirring assembly 22 was 8m/s. The ternary precursor product obtained by the positive electrode material precursor coprecipitation reaction device in the eleventh embodiment has uniform particle size and no damage on the particle surface in the application process of producing the ternary precursor by the actual positive electrode material precursor coprecipitation reaction device.

Embodiment twelve: the volume of the tank 21 is 80L, and the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction is 30mm. The stirring line speed of the stirring assembly 22 was 8m/s. The three-way precursor product obtained by the positive electrode material precursor coprecipitation reaction device in the twelve-way embodiment in the application process of producing the three-way precursor by the actual positive electrode material precursor coprecipitation reaction device has uniform particle size and no damage on the particle surface.

Embodiment thirteen: the volume of the tank 21 is 100L, and the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction is 40mm. The stirring line speed of the stirring assembly 22 was 8m/s. The three-way precursor product obtained by the positive electrode material precursor coprecipitation reaction device in the application process of producing the three-way precursor by the actual positive electrode material precursor coprecipitation reaction device has uniform particle size and no damage on the particle surface.

For the eleven, twelve and thirteen embodiments, which are all suitable manufacturing test machines, the data obtained for the actual production determination of the production process are used for the user to determine the production process.

Fourteen examples: the volume of the tank 21 is 0.6m ³, and the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction is 100mm. The stirring line speed of the stirring assembly 22 was 8m/s. The three-way precursor product obtained by the cathode material precursor coprecipitation reaction device in the fourteen embodiments in the application process of producing the three-way precursor by the actual cathode material precursor coprecipitation reaction device has uniform particle size and no damage on the particle surface.

Example fifteen: the volume of the tank 21 is 5m ³, and the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction is 120mm. The stirring line speed of the stirring assembly 22 was 8m/s. The three-way precursor product obtained by the cathode material precursor coprecipitation reaction device in the fifteen embodiment in the application process of producing the three-way precursor by the actual cathode material precursor coprecipitation reaction device has uniform particle size and no damage on the particle surface.

Example sixteen: the volume of the tank 21 is 8m ³, and the distance between the first virtual cylindrical surface and the second virtual cylindrical surface in the radial direction is 150mm. The stirring line speed of the stirring assembly 22 was 8m/s. The three-way precursor product obtained by the positive electrode material precursor coprecipitation reaction device in the sixteenth embodiment has uniform particle size and no damage on the particle surface in the application process of producing the three-way precursor by the actual positive electrode material precursor coprecipitation reaction device.

The fourteen, fifteen and sixteen embodiments are mainly applicable to actual cathode material precursor coprecipitation reaction production equipment.

Microscopic schematic diagrams of the precursor products obtained in the above examples one to sixteen. As shown in fig. 8, it can be seen from the microscopic schematic diagram that the obtained ternary precursor product has uniform particle size and no breakage on the particle surface. Other structural modules in the positive electrode material precursor coprecipitation reaction device applied to the positive electrode material precursor coprecipitation reaction device in all the embodiments can be existing modules, and the improved structural modules in the invention can be adopted, so that when the improved structural modules are combined with other structural modules in the invention, the production effects of the precursors are mutually improved.

The improvement in the backflushing structure of the filter assembly of the present invention is further described below:

As shown in fig. 1, the positive electrode material precursor coprecipitation reaction system includes:

A tank 21 for containing a precursor slurry; an input unit for inputting the precursor slurry into the tank 21; a stirring assembly 22 disposed in the tank 21 for stirring the precursor slurry in the tank 21; a filter assembly 23 disposed in the tank 21 for intercepting the precursor in the tank 21 to obtain concentrated precursor slurry and filtering out a filtered liquid; and the back flushing device is used for carrying out back flushing regeneration on the filter assembly 23, and the primary back flushing quantity of the back flushing device is 1-2 times of the total volume of the filter assembly 23 which is back flushed once. At least two groups of filter components 23 are arranged in the tank body 21, and the primary recoil quantity of the recoil device is 1-2 times of the total volume of one group of filter components 23. The recoil device includes: a backflushing vessel 8 for containing backflushing gas/backflushing liquid, the outlet of the backflushing vessel 8 being connected to the filtered liquid outlet of the filter assembly 23 to be regenerated; an intake control assembly for controlling the input of regeneration gas into the backwash vessel 8; a liquid inlet control component for controlling the regenerated liquid to be input into the backflushing container 8; a back flushing control unit for controlling the regeneration gas/regeneration liquid to be outputted from the back flushing container 8 through the outlet of the back flushing container 8. The recoil control assembly includes a recoil tube connected to the liquid outlet of the recoil vessel 8 and a pneumatic ball valve 112 disposed on the recoil tube. The back flushing pipe is branched out of a back flushing bypass pipe 111 corresponding to each group of filter components 23, a manual ball valve 1022 is arranged on each back flushing bypass pipe 111, and each group of filter components 23 is connected with the back flushing container 8 through the back flushing bypass pipe 111.

A sight glass 113 is provided on each recoil bypass tube 111. The air inlet control assembly comprises an air inlet pipe 91 connected with an air source, a pneumatic ball valve 92, a pressure gauge 93 and a stop valve 94 which are arranged on the air inlet pipe 91. The liquid inlet control assembly comprises a liquid inlet pipe 101 connected with a regeneration liquid source and a manual ball valve 102 arranged on the liquid inlet pipe 101. The volume of the backflushing vessel 8 is 1.5-2.5 times the volume of the filter assembly 23 that is backflushed at a time. The device also comprises a clean-out component and a pure water control component, wherein the clean-out component is used for discharging the filtered liquid, the pure water control component is respectively connected with the clean-out component and the backflushing device, and the pure water control component is used for controlling pure water to enter the clean-out component and the backflushing device. During backflushing, different buffer modes are selected according to different material requirements. The advantage of backflushing liquid for backflushing is that: the abrasion to the filter assembly is smaller, so that the partial pressure of oxygen in the material is not influenced; the advantage of gas backflushing is that: better control and fewer valves. Therefore, when the device is specifically used, different recoil modes can be selected according to different material properties.

Under the condition that other experimental conditions are the same, the applicant carries out the backflushing test on the condition that the primary backflushing quantity is 1, 1.5 and 2 times of the total volume of the filter assembly 23 which is backflushed once, and under the condition, the condition can ensure that the filter assembly which is backflushed once is just completely backflushed, the condition that the backflushing of the filter assembly 23 is incomplete is avoided, and the condition that the filter assembly 23 is filtered through is avoided.

Under the condition that other experimental conditions are the same, four groups of filter assemblies 23 are arranged in the tank body 21, and the applicant carries out a backflushing test on the backflushing device of the tank body, wherein the primary backflushing quantity of the backflushing device is 1, 1.5 and 2 times of the total volume of the group of filter assemblies 23, so that the condition that the backflushing of the filter assemblies which are backflushed once is just completely performed can be ensured, the condition that the backflushing of the filter assemblies 23 is incomplete can not be caused, and the condition that the filter assemblies 23 are penetrated and filtered can not be caused.

Fig. 10 is a schematic illustration of the attachment of the filter cake to the filter assembly 23. The positive electrode material precursor coprecipitation reaction system can ensure that the once-backflushed filter assembly is just completely backflushed during backflushing, can not cause incomplete backflushing of the filter assembly 23, and can not cause the condition of filtration of the filter assembly 23.

Because the filtered liquid contains 10-15% sodium sulfate, the filtered liquid is easy to crystallize in the backflushing pipeline of the clear pipeline box, and therefore, the pure water component allows pure water to enter the clear pipeline and the backflushing pipeline for flushing.

Wherein the sight glass can look over the condition of straining, and the observation filter core is that the precision is good or appear the turbidity of different degree.

The improvement of the present invention in the filter assembly mounting structure of the cathode material precursor coprecipitation reaction apparatus is further described below.

As shown in fig. 2 to 3, the cathode material precursor coprecipitation reaction apparatus of the present invention includes: a tank 21 for containing a precursor slurry; an input unit for inputting the precursor slurry into the tank 21; a stirring assembly 22 disposed in the tank 21 for stirring the precursor slurry in the tank 21; the filtering component 23 comprises a plurality of filtering units which are circumferentially distributed in the tank body 21 around the stirring component 22 and are used for intercepting the precursor in the tank body 21 to obtain concentrated precursor slurry and filtering out filtered liquid; the filter assembly 23 comprises a filtering liquid pipe fixed in the tank body 21 and a filtering filter element 235 fixed on the filtering liquid pipe at intervals, the filtering liquid pipe comprises an outer ring pipe 231 and an inner ring pipe 232 which are radially distributed from outside to inside along the tank body 21, the outer ring pipe 231 and the inner ring pipe 232 are externally connected with a clear liquid outlet system through the clear liquid outlet pipe 233, and the outer ring pipe 231 and the inner ring pipe 232 are sealing pipes.

The invention also provides the following four different connection modes of the filtering liquid pipe and the clear liquid outlet pipe:

The first connection is shown in fig. 4: the outer ring pipe 231 is externally connected with a clear liquid outlet system through a clear liquid outlet pipe 233, and the inner ring pipe 232 and the outer ring pipe 231 are connected and communicated through a horizontal straight pipe 234. Wherein both ends of the horizontal straight pipe 234 are welded to the inner and outer ring pipes 232 and 231, respectively, by T-shaped welding structures. When the clear liquid outlet on the tank body 21 is arranged on the bottom of the tank body 21, the clear liquid outlet pipe 233 can be a straight pipe which extends vertically downwards to the outside of the tank body 21 and is communicated with the clear liquid outlet component; when the clear liquid outlet on the tank 21 is provided on the side of the tank 21, the clear liquid outlet pipe 233 may be an elbow extending to the outside of the tank 21 to communicate with the clear liquid outlet assembly.

The second connection is shown in fig. 5: the outer ring pipe 231 and the inner ring pipe 232 are positioned at the same height, the outer ring pipe 231 is externally connected with a clear liquid outlet system through a clear liquid outlet pipe 233, and the inner ring pipe 232 is connected with the clear liquid outlet pipe 233 through a bent pipe 236 and is communicated with the clear liquid outlet pipe 233. When the clear liquid outlet on the tank body 21 is arranged on the bottom of the tank body 21, the clear liquid outlet pipe 233 can be a straight pipe which extends vertically downwards to the outside of the tank body 21 and is communicated with the clear liquid outlet component; when the clear liquid outlet on the tank 21 is provided on the side of the tank 21, the clear liquid outlet pipe 233 may be an elbow extending to the outside of the tank 21 to communicate with the clear liquid outlet assembly.

The third connection is shown in fig. 6: the setting height of inner circle pipe 232 is higher than the setting height of outer lane pipe 231, outer lane pipe 231 passes through play clear liquid pipe 233 external clear liquid system, inner circle pipe 232 is connected and switches on with play clear liquid pipe 233 through return bend 236. When the clear liquid outlet on the tank body 21 is arranged on the bottom of the tank body 21, the clear liquid outlet pipe 233 can be a straight pipe which extends vertically downwards to the outside of the tank body 21 and is communicated with the clear liquid outlet component; when the clear liquid outlet on the tank 21 is provided on the side of the tank 21, the clear liquid outlet pipe 233 may be an elbow extending to the outside of the tank 21 to communicate with the clear liquid outlet assembly.

The fourth connection is shown in fig. 7: the outer ring pipe 231 and the inner ring pipe 232 are independently arranged, and the inner ring pipe 232 and the outer ring pipe 231 are respectively externally connected with a clear liquid outlet system through independent clear liquid outlet pipes 233. When the clear liquid outlet on the tank body 21 is arranged on the bottom of the tank body 21, the clear liquid outlet pipe 233 can be a straight pipe which extends vertically downwards to the outside of the tank body 21 and is communicated with the clear liquid outlet component; when the clear liquid outlet on the tank 21 is provided on the side of the tank 21, the clear liquid outlet pipe 233 may be an elbow extending to the outside of the tank 21 to communicate with the clear liquid outlet assembly. In this connection, in order to better install the clear liquid outlet pipe 233, one end of the inner ring pipe 232 is longer than the corresponding end of the outer ring pipe 231, the clear liquid outlet pipe 233 of the inner ring is connected to and conducted with the end of the inner ring pipe 232, and the clear liquid outlet pipe 233 of the outer ring is connected to and conducted with the end of the outer ring pipe 231.

As a preferable example, referring to fig. 2-3, the inner ring pipe 232 and the outer ring pipe 231 are radially provided with fixing members, and the fixing members are externally provided from inside to outside. The fixing piece is a fixing rod 121, and two ends of the inner ring pipe 232 and the outer ring pipe 231 are respectively connected with the fixing rod 121 through welding; or both ends of the inner ring pipe 232 and the outer ring pipe 231 are fixed to the fixing rod 121 by the anchor members 122. The inner ring pipe 232 and the outer ring pipe 231 are arc-shaped pipes. The filter assembly 23 comprises four filter units, and the central angle of the arc-shaped pipe is 75-80 degrees. As shown in fig. 11, the installation position of the filter element 235 on the outer ring pipe 231 is offset from the installation position of the filter element 235 on the inner ring pipe 232.

The filter assembly 23 may be fixed at both upper and lower ends or only at the lower end when installed. When the filter component is installed, the lower end of the filter component is connected with a mounting hole formed in the upper end of the filtering liquid pipe through threads, and the upper end of the filter component is fixedly connected with the tank body through angle steel. The filter component can be one of a titanium alloy filter element, a 316 stainless steel filter element, a 2205 duplex stainless steel filter element, a silicon carbide material, a PVDF filter element and the like. Shan Duangu it is determined that a cartridge breakage accident may occur when the length of the filter assembly itself is long, and thus when the filter assembly having a length exceeding 500mm is applied to the positive electrode material precursor coprecipitation reaction apparatus of the present invention, double-ended fixation is adopted.

It should be noted that, the structural features of the four connection modes may be combined into other connection modes through permutation, and these connection modes are also within the protection scope of the present invention.

When the precursor system is applied to the production of ternary precursors, the specific composition of the reaction kettle 1 can be determined according to the reaction time of specific materials because the reaction time of materials with different proportions and different compositions is different, for example, when the reaction time of ternary precursor slurry is faster, the reaction kettle 1 only adopts a main reaction kettle; when the ternary precursor slurry is slower in reaction, the reaction kettle 1 adopts a structure that a main reaction kettle is connected with a secondary reaction kettle. The ternary precursor slurry firstly enters the reaction kettle 1 for reaction and then enters the positive electrode material precursor coprecipitation reaction equipment 2, enrichment and concentration of the ternary precursor slurry are realized in the positive electrode material precursor coprecipitation reaction equipment 2, the clear quantity of the filtered liquid of the tank body is controlled to be consistent with the liquid inlet quantity of the reaction kettle and the liquid level of the ternary precursor slurry in the tank body is controlled to be stable in the operation process of the ternary positive electrode material precursor coprecipitation reaction equipment, so that the system is connected with stable operation, the quality of a product of the ternary precursor is stable, the filter assembly is fully regenerated regularly through the filter assembly regeneration system, and the filtering flux of the filter assembly is ensured.

The content of the present invention is described above. Those of ordinary skill in the art will be able to implement the invention based on these descriptions. Based on the foregoing, all other embodiments that may be obtained by one of ordinary skill in the art without undue burden are within the scope of the present invention.

Claims

1. The positive electrode material precursor coprecipitation reaction system is characterized by comprising:

A tank (21) for containing a precursor slurry;

An input unit for inputting the precursor slurry into the tank (21);

the stirring assembly (22) is arranged in the tank body (21) and is used for stirring the precursor slurry in the tank body (21);

The filtering component (23) is arranged in the tank body (21) and is used for intercepting the precursor in the tank body (21) to obtain concentrated precursor slurry and filtering out filtered liquid;

The back flushing device is used for carrying out back flushing regeneration on the filter assembly (23), and the primary back flushing quantity of the back flushing device is 1-2 times of the total volume of the filter assembly (23) which is back flushed once;

the recoil device includes:

The backflushing container (8) is used for containing backflushing gas/backflushing liquid, and an outlet of the backflushing container (8) is connected with a filtered liquid outlet of the filtering component (23) to be regenerated;

an inlet control assembly for controlling the input of regeneration gas into the backwash vessel (8);

the liquid inlet control assembly is used for controlling the regenerated liquid to be input into the backflushing container (8);

A back flushing control assembly for controlling the regeneration gas/regeneration liquid to be outputted from the back flushing container (8) through the outlet of the back flushing container (8);

the filter assembly (23) comprises a plurality of filter elements which are circumferentially arranged in the tank body (21), and the total volume of the filter assembly (23) is the sum of the internal volumes of the filter elements;

The positions of the stirring blades of the stirring assembly (22) at the end part of the tank body (21) in the radial direction during stirring are all located on a first virtual cylinder surface, the positions of the closest stirring blades on the filtering surfaces of all the filtering assemblies are all located on a second virtual cylinder surface, and the ratio of the distance between the first virtual cylinder surface in the radial direction of the tank body (21) and the second virtual cylinder surface to the inner diameter of the tank body (21) is 5% -15%;

When the volume of the tank body (21) is 50-100L, the distance between the first virtual cylinder surface and the second virtual cylinder surface in the radial direction is 20-40mm;

When the volume of the tank body (21) is 0.6-8m ³, the distance between the first virtual cylinder surface and the second virtual cylinder surface in the radial direction is 100-150mm;

the stirring linear speed of the stirring assembly (22) is 5-10m/s.

2. The positive electrode material precursor coprecipitation reaction system according to claim 1, wherein at least two groups of filter components (23) are arranged in the tank body (21), and one-time recoil quantity of the recoil device is 1-2 times of the total volume of one group of filter components (23).

3. The positive electrode material precursor coprecipitation reaction system according to claim 2, wherein the backflushing control assembly includes a backflushing tube connected to a liquid outlet of the backflushing container (8) and a pneumatic ball valve (112) provided on the backflushing tube.

4. A positive electrode material precursor coprecipitation reaction system according to claim 3, wherein the backflushing pipes are branched out of backflushing bypass pipes (111) corresponding to each group of filter components (23), each backflushing bypass pipe (111) is provided with a manual ball valve (112), and each group of filter components (23) is connected with the backflushing container (8) through the backflushing bypass pipe (111) respectively.

5. The positive electrode material precursor coprecipitation reaction system according to claim 4, wherein a sight glass (113) is provided on each of the recoil bypass pipes (111).

6. The positive electrode material precursor coprecipitation reaction system according to claim 1, wherein the air inlet control assembly includes an air inlet pipe (91) connected with an air source, and a pneumatic ball valve (92), a pressure gauge (93) and a stop valve (94) arranged on the air inlet pipe (91).

7. The positive electrode material precursor coprecipitation reaction system according to claim 1, wherein the liquid inlet control assembly includes a liquid inlet pipe (101) connected to a regeneration liquid source and a manual ball valve (102) provided on the liquid inlet pipe (101).

8. The positive electrode material precursor coprecipitation reaction system according to claim 1, wherein the volume of the back flushing container (8) is 1.5 to 2.5 times the volume of the filter assembly (23) that is back flushed at a time.

9. The positive electrode material precursor coprecipitation reaction system according to claim 1, further comprising a clean-out component and a pure water control component, wherein the clean-out component is used for discharging a filtering liquid, the pure water control component is respectively connected with the clean-out component and the backflushing device, and the pure water control component is used for controlling pure water to enter the clean-out component and the backflushing device.