KR101765471B1 - Superheated steam generating apparatus for manufacturing process of secondary cell - Google Patents

Abstract

The present invention relates to an overheated steam generator for a secondary battery manufacturing process. The present invention provides a line heater comprising: a line heater for supplying dry air to a first temperature range and preheating the dry air to a second temperature range; And an induction heater for reheating the preheated steam and the vapor to a third temperature range to generate superheated steam and supply the superheated steam to the chamber through the superheated steam supply line; And the first temperature range to the third temperature range are set to be sequentially higher.

Description

Technical Field [0001] The present invention relates to a superheated steam generating apparatus for a secondary battery manufacturing process,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superheated steam generator for a secondary battery manufacturing process and more particularly to a superheated steam generator for manufacturing a secondary battery for providing a process using superheated steam for increasing the drying speed, The present invention relates to an overheated steam generator for a steam generator.

As the global eco-friendly energy market is expected to expand and grow, the market for lithium-ion rechargeable batteries is expected to expand in the mid- to long-term.

In 2014, the market for lithium-ion rechargeable batteries with a capacity of 50 GW · h (gigawatt) has expanded to 67.6 GW · h as of 2015, and the battery market for electric vehicles (xEV) is expected to increase to 274.9 GW · h in 2020, Year-on-year growth.

In other words, the market expansion of the electric car market and the leadership of the lithium ion secondary battery market are expected to shift from small IT batteries to mid- to large-sized batteries for electric vehicles and hybrid electric vehicles (HEVs).

As the market for lithium secondary batteries grows, it is necessary to maintain the current level of battery performance as well as increase the yield in order to produce the batteries required in the market. The electrode manufacturing process, which is considered to be the most important part of the battery production process, is rapidly producing battery electrode plates through automation of the coating process and the drying process, and the improvement of the drying performance is directly related to the product yield.

The manufacturing process of the secondary battery electrode is the first process in the production of the secondary battery, and this is the most important process that determines the performance of the battery.

Particularly, the electrode coating and drying process, which is a process of applying an electrode to an aluminum foil, requires a high precision and stable supply as a starting point for carrying out a post-process. In addition, there is a problem that needs to be solved in order to meet the increasing amount of the battery production, that is, the supply amount due to the expansion of the market.

As a first problem, the current mass production line is over 50 to 100 meters in size. To reduce the scale of mass production facilities, the production line has been made in multiple layers.

Second, the expansion of the facility is an inevitable measure to solve the drying efficiency, that is, the drying of the electrode perfectly and rapidly. If the electrodes are coated on the aluminum foil of 10 tons in the thickness of 150 μm, It can only be processed for 22 days (about a month) without completing the process line to finish.

Due to these problems, it is urgently required to improve the drying speed of the coating and drying equipment (hereinafter, dry coater), that is, the drying efficiency.

The conventional drying method directly or indirectly supplies 'hot air', which is dried air, to remove the solvent contained in the drying object. That is, the ventilated dryer, which is currently used in the drying process, is a drying process using hot air, and it can be said that the drying process is performed by supplying heated air (hot air) through the pores in the material of the material to be dried.

In this case, the drying efficiency is high because a direct contact area with the material forming the drying object is large and a path through which moisture can diffuse therein is short.

However, a suitable pore distribution, that is, a material having a proper porosity, can attain a high drying efficiency, but in the case of a material having a low porosity or a plate material, pressure must be accompanied and the crack The peeling phenomenon of the coating layer may occur.

In addition, such a ventilating drying technique determines the drying speed depending on the temperature and humidity of the heated air, and the heating time and the residence time of the heated air are short and the amount of heat discharged from the exhaust gas (latent heat of the dry air and latent heat of the steam) There is a disadvantage that the energy loss is large.

Accordingly, there is a need in the art to develop a technology for a new process for increasing the drying speed, that is, drying efficiency.

Korean Patent Laid-Open Publication No. 10-2006-0004057 entitled " Method for producing a polymer-coated lithium secondary battery " Korean Patent Registration No. 10-0359054 entitled "Metal oxide anode surface-treated with conductive slurry, method for producing the same, and lithium secondary battery using the same"

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a method of manufacturing a secondary battery, in which the energy loss is reduced as compared with the conventional ventilation type drying method, Device.

The present invention also provides a superheated steam generator for achieving a higher energy transfer efficiency than the conventional drying method using a dry drying method in terms of energy transfer rate by using superheated steam having a high energy efficiency per unit weight .

The present invention also provides a superheated steam generator for maintaining the temperature of each of the heaters, the superheated steam, and other chambers at a target temperature.

However, the objects of the present invention are not limited to the above-mentioned objects, and other objects not mentioned can be clearly understood by those skilled in the art from the following description.

In order to accomplish the above object, in a superheated steam generator for a secondary battery manufacturing process according to an embodiment of the present invention, when steam heated to a first temperature range is supplied, dry air is supplied and preheated to a second temperature range Line heaters; And an induction heater for reheating the preheated steam and the vapor to a third temperature range to generate superheated steam and supply the superheated steam to the chamber through the superheated steam supply line, wherein the first temperature range to the third temperature range are sequentially .

At this time, the line heater is supplied with steam heated at 100 to 115 ° C for the first time through a pipeline at 150 to 250 kg / min, and at the same time, supplied to the line air at 700 to 1100 L / And the induction heater heats the steam supplied from the line heater to 380 ° C ± 20 ° C.

The line heater may further include: a first lap joint flange connected to a duct for receiving dry air at the same time as the steam heated to the first 100 to 115 ° C; And a second lap portion formed to join the main heating pipe of the line heater main pipe and the induction heater together with the lower end joint flange of the induction heater, And a joint flange.

The line heater may measure a temperature to maintain the temperature of the steam supplied to the second induction heater through the second lap joint flange in a range of 250 ° C to 310 ° C, A temperature control sensor which functions to raise and lower the temperature of the temperature sensor; And further comprising:

The line heater detects an overspeed of the line heater in a stepwise manner so as to prevent a temperature change inside the line heater main pipe caused by a plurality of heating lines in the line heater main pipe, A superheat on prevention sensor positioned between the second lap joint flange and the reducer; And further comprising:

At this time, it is preferable that the reducer is formed at the longitudinal end of the line heater main pipe to prevent the line heater main pipe from being deformed or broken due to high temperature or pressure.

In addition, it is preferable that the shape of the line heater in the line heater main pipe is formed in an oblique cross-section between the respective heating lines.

Preferably, the induction heater reheats the preheated steam at a temperature ranging from 250 ° C. to 310 ° C. through the line heater to 380 ° C. ± 20 ° C. to generate superheated steam and deliver the superheated steam to the superheated steam supply line.

The induction heater preferably has a structure in which a predetermined number of internal plates serving as a flow path are arranged to heat the steam passing through the induction heater so that the steam can be delayed therein.

In addition, the induction heater is wound on a main heating pipe corresponding to a conductor, and an eddy current generated in the main heating pipe due to an electromagnetic induction phenomenon as a current flows generates steam, thereby heating the steam passing through the induction heater Induction cable; And a heat insulating material disposed between the induction cable and the main heating pipe to prevent the temperature of the steam heated while passing through the main heating pipe from being influenced by an external temperature. .

The induction heater has a shape in which a heat insulating material for the main heating pipe and a side portion of the main heating pipe are inserted through an area where the inner plate is not formed in an intermediate region of the main heating pipe, A temperature sensor for induction control to be transmitted to an output controller; .

Also, the output controller controls the temperature of the main heating pipe by the electromagnetic induction phenomenon so that the temperature is maintained in the range of 380 ° C ± 20 ° C until passing through the bending pipe on the basis of the intermediate temperature for supplying the superheated steam to the superheated steam supply line. It is preferable to control the rise and fall of the internal temperature.

In addition, the bending pipe is preferably formed of a heat insulating member.

The superheated steam generator according to the embodiment of the present invention provides a higher energy transfer efficiency than the conventional drying method using the drying method of the drying method by using the superheated steam having a high energy efficiency per unit weight do.

In addition, the overheated steam generator according to another embodiment of the present invention reduces the energy loss as compared with the conventional ventilation type drying system, thereby improving the drying speed and drying efficiency of the secondary battery.

In addition, the superheated steam generator according to another embodiment of the present invention provides the effect of maintaining the temperature at the target temperature inside the line heater, induction heater, superheated steam supply, and other chambers.

FIG. 1A shows the diffusion coefficient according to the moisture content, and FIG. 1B is a chart showing the relationship between the reverse temperature and the drying speed.
BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a superheated steam generator for a secondary battery manufacturing process.
3 is a view showing a line heater among the overheated steam generating apparatuses for the secondary battery manufacturing process of FIG.
FIG. 4 is a view showing an induction heater among the overheated steam generating apparatuses for the secondary battery manufacturing process of FIG. 2;
FIG. 5 is a graph showing the temperature profile of the components and the target in the chamber in the superheated steam generator for the battery fabrication process according to the embodiment of the present invention. FIG.

The present invention can be variously modified and may have various embodiments, and specific embodiments will be described in detail with reference to the drawings. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Terms including ordinals, such as first, second, etc., may be used to describe various elements, but the elements are not limited to these terms. The terms are used only for the purpose of distinguishing one component from another.

For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be construed as ideal or overly formal in meaning unless explicitly defined in the present application Do not.

Hereinafter, the features of the hot air drying method used in the present invention and preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the case of the "hot air drying type" coater, which is currently applied to the mass production line, facilities are being manufactured to improve productivity. Therefore, for mass production, it is necessary to increase the coating width by increasing the coating width of the coating M / C, or to increase the drying speed of the coating M / C, To increase production.

However, due to the high material density due to the high material density of the anode, the bending phenomenon of the substrate occurs seriously when exposed to a wide coating width or a long time drying condition, and the quality of the product (electrode) the difficulty of tension control occurs in roll-to-roll.

Therefore, it is absolutely required that a coating apparatus (coating M / C) capable of drying at a high speed while maintaining the quality of the electrode currently being commercialized and having a small size.

In the present invention, the problem of the quality of the dry electrode, which is a problem of the mass production line that is now being derived, is solved by using the superheated steam drying method. In the superheated steam drying method, the temperature of the superheated steam during the drying period is larger than the temperature of the heated air, thereby reducing the temperature difference between the steam and the dried material.

Therefore, the inversion temperature at which the evaporation rate of the water becomes the same at the time of drying the superheated steam and the hot air occurs, and the superheated steam dries faster than the hot air at the temperature higher than the reversed temperature. Typically, the range of inversion temperatures is between 150 ° C and 200 ° C, and the inversion temperature may be lower if the heat is supplied in an indirect manner (conduction or radiation).

However, it is not necessary to operate the superheated steam drier only above the reversing temperature, since the drying rate of the superheated steam is higher than the drying temperature of the superheated steam above the reversing temperature.

Reduction rate in drying of superheated steam Since the drying temperature is high during the drying period and there is no diffusion resistance for evaporation of water, the rapid drying speed is maintained, so that the total drying time is shortened even under the reverse temperature.

Fig. 1A shows diffusion coefficients according to a generally known moisture content, and Fig. 1B is a table of known contents used for illustrating the relation between the reversing temperature and the drying speed.

First, referring to FIG. 1A, the relationship between total diffusion coefficient and moisture content by using superheated steam drying and hot air drying is shown at different drying temperatures in the reduction drying period, The moisture absorption diffusion increases when the moisture content is small. In addition, it can be seen that as the drying temperature increases, the diffusion coefficient increases, and that the effect of diffusion on the superheated steam drying is greater than that of the hot air drying.

For example, when the moisture content is 0.08 kg / kg · db, the drying temperature is increased from 125 ° C. to 165 ° C., and the overall diffusion coefficient is larger at the superheated steam drying than the hot air drying.

In addition, the total diffusion coefficient is larger when the drying temperature is 145 ° C and 165 ° C than when it is superheated steam, but it is higher than that of superheated steam drying when the drying temperature is 125 ° C. That is, referring to FIG. 1B, it can be seen that the drying speed of the superheated steam drying process is significantly faster than that of the hot air drying process at the temperatures of 145 ° C and 165 ° C (B, C) above the reversal temperature.

On the other hand, the results of simple comparison between the conventional hot air, i.e., the drying process using heated air and the drying method using the superheated steam to be applied in the present invention, ]. As shown in Table 1, there is a difference of 22.5 times between the superheated steam having a pressure of 1 kg / cm 2 G and the heated gun air at an atmospheric temperature of 20 ° C to 200 ° C, It can be seen that the drying method obtains an energy transfer effect 22 times higher than the drying method using the heating gun air method. This corresponds to high energy efficiency per unit weight.

Super Steam Drying Method Hot air drying method Energy efficiency
● Condition: Steam pressure 1㎏ / ㎠G.
Temperature: 200 캜, outside temperature: 20 캜

● Superheated Steam Heat - 20 ℃ water retained calories
741.1 kcal / kg - 20 kcal / kg
= 721.1 kcal / kg (calorie difference 22 times or more) ● Condition: Air pressure 1kg / ㎠G.
Temperature: 200 캜, outside temperature: 20 캜

● Specific heat temperature difference
0.178 kcal / kg 占 폚 占 180 占 폚
= 32.04 kcal / kg
Electric heating system
Convection heat + Radiation heat + Condensation heat
Convection heat

Accordingly, the present invention proposes a 'superheated steam generator' capable of generating and supplying superheated steam as described above, thereby improving the drying speed of the dry coater, which is a coating and drying equipment during the manufacturing process of the secondary battery I want to.

2 is a view showing an overheated steam generator 100 for a secondary battery manufacturing process according to an embodiment of the present invention.

2, the configuration of the overheated steam generator 100 for a secondary battery manufacturing process includes a 20 kW line heater 110 corresponding to the first heater, a 30 kW induction heater corresponding to the second heater 120), and an overheated steam supply line (130).

According to such a configuration, the overheated steam generator 100 for the secondary battery manufacturing process is operated by supplying steam heated to 100 to 115 ° C at 150 to 250 kg / min, and dry air at 700 to 1100 L / , And then heated to 250 ° C to 310 ° C in the first case. The first heated steam and the dry air are reheated through the induction heater 120 to a second temperature of 380 ° C ± 20 ° C to stably supply the superheated steam to the chamber through the superheated steam supply line 130.

3 is a cross-sectional view of the line heater 110 in the superheated steam generator 100 for the secondary battery manufacturing process of FIG. 2, and FIG. 3B is a longitudinal sectional view thereof.

Referring to FIG. 3, the line heater 110, which is the first heater, is supplied through a channel accommodating the steam heated to the first 105 to 110 ° C., and at the same time, And serves to transfer the steam to the induction heater 120, which is the second heater, in a state of preheating the steam through the first heating. The temperature of the steam supplied to the second induction heater 120 should be steadily / continuously supplied in the range of 250 ° C to 310 ° C.

More specifically, the line heater 110 includes a first lap joint flange 111, a second lap joint flange 112, a temperature control sensor 113, 114 and a reducer 115. [

The first lap joint flange (111) is connected to the duct for supplying the dry air at the same time as the steam heated to the first 105 to 110 ° C.

The second lap joint flange 112 is located at the uppermost end of the pipe for supplying the steam supplied to the second induction heater 120. The second lap joint flange 112 is connected with the lower end joint flange of the induction heater 120, The line heater main pipe 116 of the heater 110 and the main heating pipe 122 of the induction heater 120 are formed.

 The temperature control sensor 113 measures the temperature to maintain the temperature of the steam supplied to the second induction heater 120 through the second lap joint flange 112 in the range of 250 캜 to 310 캜, 116 to raise and lower the temperature of the heating line HL.

The overheat prevention sensor 114 detects the overheating of the line heater main pipe 116 step by step so as to prevent the temperature change inside the line heater main pipe 116 due to a plurality of heating lines in the line heater main pipe 116, Is formed between the second lap joint flange (112) and the reducer (115) in the longitudinal direction of the second lap joint flange (112).

The reducer 115 is formed at the longitudinal end of the line heater main pipe 116 to prevent deformation and breakage of the line heater main pipe 116 due to high temperature or pressure of the line heater main pipe 116.

Meanwhile, the shape of the line heater inside the line heater main pipe 116 is formed in a slant line shape crossing each heating line as shown in FIG. 3B, thereby maximizing thermal efficiency.

FIG. 4 is a view showing an induction heater 120 of the overheated steam generator 100 for the secondary battery manufacturing process of FIG. 2. Referring to FIG. Referring to FIG. 4, the induction heater 120 reheats the steam preheated in the temperature range of 250 ° C. to 310 ° C. through the line heater 110 to 380 ° C. ± 20 ° C. to generate superheated steam, ).

The induction heater 120 is configured to pass through an inner plate (inner plate: I.p.) 86 which serves as a flow path to heat the induction heater 120, thereby providing a structure in which the heating body by the induction heater 120 can be delayed therein.

More specifically, the induction heater 120 includes an induction cable 121, a main heating pipe 122, a main heating pipe insulation 123, an induction control temperature sensor 124, a bending pipe 125, and an output controller 126 ).

The induction cable 121 is wound around the main heating pipe 122 corresponding to the conductor. The eddy current generated in the main heating pipe 122 by the electromagnetic induction phenomenon as a current flows generates steam, Lt; / RTI >

The heat insulating material 123 for the main heating pipe is positioned between the induction cable 121 and the main heating pipe 122 so that the temperature of the steam heated while passing through the main heating pipe 122 is not influenced by the external temperature It plays a role.

The temperature sensor 124 for induction control is formed by inserting the heat insulating material 123 for the main heating pipe and the side portion of the main heating pipe 122 through an area where the inner plate is not formed in the middle area of the main heating pipe 122 And transmits the sensed temperature to the output controller 126.

The output controller 126 controls the temperature of the superheated steam supply line 130 such that the temperature of the superheated steam supply line 130 is maintained at 380 ° C ± 20 ° C before passing through the bending pipe 125, The temperature inside the main heating pipe 122 is raised and lowered.

The bending pipe 125 is formed of a heat retaining member so that the temperature of the superheated steam passing through the main heating pipe 122 is supplied to the superheated steam supply line 130 while being minimally affected by the external temperature.

Accordingly, the superheated steam supply line 130 supplies the superheated steam generated by reheating the preheated steam passing through the line heater 110 in the induction heater 120 into the chamber, thereby using the superheated steam in the chamber An electrode coating and drying process, which is a process of applying an electrode to an aluminum foil in a secondary battery fabrication process, is performed.

On the other hand, when the superheated steam is generated by the induction heater 120 and the superheated steam is supplied through the superheated steam supply line 130, the internal temperature of the superheated steam supply line 130 is maintained within 300 ° C ± 15 ° C and superheated steam is supplied into the chamber do. Due to the superheated steam thus supplied, the temperature inside the chamber can exhibit the drying performance of the aluminum foil and the electrode slurry due to the superheated steam. Also, the chamber internal temperature should be maintained at the target temperature of ± 5 ° C.

5 is a graph showing a target temperature profile in the chamber and the components inside the superheated steam generator 100 for the battery fabrication process according to the embodiment of the present invention. 5, the target temperature of the line heater 110 corresponds to 300 ° C. and the target temperature of the induction heater 120 is 380 ° C. in order to supply the superheated steam supplied into the chamber from 170 ° C. to 200 ° C. Set up and start operation.

The target temperature is reached within 7 minutes after setting the temperature, and the temperature of the supply line 130 reaches 310 ° C ± 5 ° C within 30 minutes to 35 minutes. After a total operation time of 60 minutes, the internal temperature of the chamber is maintained at 200 ± 10 ° C, and the drying chamber is operated at the drivable section of the drying coater.

As described above, preferred embodiments of the present invention have been disclosed in the present specification and drawings, and although specific terms have been used, they have been used only in a general sense to easily describe the technical contents of the present invention and to facilitate understanding of the invention , And are not intended to limit the scope of the present invention. It is to be understood by those skilled in the art that other modifications based on the technical idea of the present invention are possible in addition to the embodiments disclosed herein.

100: Superheated steam generator for secondary cell manufacturing process
110: Line heater
111: 1st lap joint flange
112: 2nd lap joint flange
113: Temperature control sensor 114: Overheat protection sensor
115: Reducer 116: Line heater main pipe
120: Induction heater 121: Induction cable
122: Main heating pipe 123: Main heating pipe insulation
124: temperature sensor for induction control 125: bending pipe
126: output controller 130: overheated steam supply line

Claims (13)

A line heater for supplying the steam heated to the first temperature range and preheating the dry air to the second temperature range; And
An induction heater for reheating the preheated steam and the steam to a third temperature range to generate superheated steam and supplying the superheated steam to the chamber through the superheated steam supply line; / RTI >
In the line heater,
The first temperature range is 150 to 250 kg / min of steam heated to the first 100 to 115 ° C, and the dry air is supplied at 700 to 1100 L / min to the second temperature range of 250 ° C Wherein the induction heater is heated to a temperature of 380 ° C ± 20 ° C as the third temperature range, wherein the steam supplied from the line heater is heated to 310 ° C to 310 ° C and supplied to the induction heater. Overheated steam generating device. delete 2. The line heater according to claim 1,
A first lap joint flange connected to a conduit for receiving dry air at the same time as the steam heated to the first 100 to 115 캜; And
And a second lap joint formed to join the main heating pipe of the induction heater and the line heater main pipe together with the lower end joint flange of the induction heater, flange; Wherein the superheated steam generator is a superheated steam generator.
4. The line heater according to claim 3,
The temperature is measured to maintain the temperature of the steam supplied to the second induction heater through the second lap joint flange in the range of 250 ° C to 310 ° C to raise and lower the temperature of the heating line inside the line heater main pipe Temperature control sensors that serve for; Further comprising a second superheated steam generator for generating a superheated steam.
4. The line heater according to claim 3,
In order to prevent a temperature change inside the line heater main pipe due to a plurality of heating lines in the line heater main pipe from being detected in a stepwise manner in the longitudinal direction of the line heater main pipe, An overheating protection sensor located between the ducers; Further comprising a second superheated steam generator for generating a superheated steam.
6. The apparatus of claim 5,
Wherein the line heater main pipe is formed at a longitudinal end of the line heater main pipe in order to prevent deformation and destruction of the line heater main pipe due to high temperature or pressure.
The method of claim 4,
Wherein the shape of the line heater in the line heater main pipe is formed in a slanting shape in cross section between the respective heating lines.
The induction heater according to claim 1,
Wherein the superheated steam is supplied to the superheated steam supply line through the line heater, and the superheated steam is generated by reheating the steam preheated to a temperature range of 250 to 310 ° C through the line heater to 380 ° C ± 20 ° C. Generating device.
The induction heater according to claim 1,
Wherein a predetermined number of inner plates serving as a flow path are arranged inside the steam generator so that the steam is heated while passing through the steam to provide a structure in which the steam can be delayed in the steam generator. .
The induction heater according to claim 9,
An induction cable wound around a main heating pipe corresponding to a conductor and generating an eddy current generated in the main heating pipe due to an electromagnetic induction phenomenon as a current flows, thereby heating the steam passing through the induction cable; And
A heat insulating material for a main heating pipe positioned between the induction cable and the main heating pipe to prevent the temperature of the steam heated while passing through the main heating pipe from being influenced by an external temperature; Wherein the superheated steam generator is a superheated steam generator.
The induction heater according to claim 10,
The main heating pipe and the main heating pipe are inserted into a region where the inner plate is not formed in the middle region of the main heating pipe and the side portions of the main heating pipe and the induction control temperature Senser; Further comprising a second superheated steam generator for generating a superheated steam.
12. The apparatus of claim 11,
The temperature of the inside of the main heating pipe is raised and lowered by electromagnetic induction so that the temperature is maintained at 380 ° C ± 20 ° C before passing through the bending pipe based on an intermediate temperature for supplying superheated steam to the superheated steam supply line Wherein the control unit controls the temperature of the secondary battery.
13. The bending machine according to claim 12,
Wherein the heat generating member is formed of a heat insulating member.

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