JP2019034254A - Apparatus and method for treating waste lithium ion battery - Google Patents

Abstract

To safely and efficiently collect valuables from a waste lithium ion battery.SOLUTION: An apparatus for treating a waste lithium ion battery includes a roller hearth kiln (heat treatment furnace) 1 having a heating region 3A for heating a waste lithium ion battery at 100°C or higher and 250°C or lower, and a roasting region 3B for roasting the heated waste lithium ion battery at 300°C or higher and 650°C or lower. An electrolytic solution is vaporized by heating the waste lithium ion battery at 100°C or higher and 250°C or lower, is then roasted at 300°C or higher and 650°C or lower to decompose a binder, which has no danger such that the electrolytic solution is rapidly vaporized and the waste lithium ion battery is burst and is safety and allows variables to be easily collected from the waste lithium ion battery in the subsequent valuable collection device. A tunnel kiln can be also used in place of the roller hearth skin. The heating region and the roasting region can be also set to be a reduction atmosphere.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an apparatus and method for treating a waste lithium ion battery, and more particularly to an apparatus and method for safely and efficiently recovering valuable materials from a waste lithium ion battery.

  A lithium ion battery is used as a power source for electric vehicles such as hybrid cars and electric cars, and is made of a positive electrode material coated with lithium, cobalt, nickel or the like on an aluminum foil, a negative electrode material coated with graphite or the like on a copper foil, an electrolyte solution, It consists of a separator and the like. Since lithium ion batteries contain valuable materials such as aluminum, lithium, cobalt, nickel, copper, etc., these are recovered from lithium ion batteries discarded after use (hereinafter abbreviated as “LIB” as appropriate). To do is extremely important for Japan, which is scarce of resources.

  In order to recover valuable materials from LIB, roasting, crushing or crushing, sieving, sorting and the like are performed.

  For example, Patent Document 1 discloses that LIB is charged into a rotary furnace and roasted at 300 to 650 ° C. in a reducing atmosphere to volatilize the electrolyte without melting aluminum contained in LIB. Disclosed is a method for facilitating the recovery of valuable materials from the manufacturing process.

  In addition, in Patent Document 2, as a pretreatment for recovering valuable materials from LIB, after LIB discharge treatment, the LIB safety valve is opened and heated at 80 to 150 ° C. under reduced pressure to vaporize the electrolyte. A method is disclosed.

  Furthermore, in Patent Document 3, the LIB is heated to 150 to 180 ° C. to volatilize the electrolytic solution, and the volatilized electrolytic solution is discharged to the outside through the safety valve to destroy the battery function of the LIB. A method of crushing a broken LIB and recovering valuable materials by sedimentation separation is disclosed.

Japanese Unexamined Patent Publication No. 2016-22395 JP 2013-229326 A Japanese Patent No. 5703844

  However, in the method described in Patent Document 1, since LIB is charged into a high-temperature furnace, it is impossible to deny the possibility that the electrolyte vaporizes rapidly and the LIB expands and bursts.

Further, in the method described in Patent Document 2, since the LIB safety valve is opened, lithium hexafluorophosphate (LiPF ₆ ) contained in the LIB electrolyte leaks, and the lithium hexafluorophosphate is decomposed. As a result, toxic hydrogen fluoride may be generated.

  Furthermore, in the method described in Patent Document 3, since the heating temperature is as low as about 160 ° C., it is possible to avoid the LIB from expanding and bursting, but PVDF (polyfluoride) as an electrode binder in the active material can be avoided. Vinylidene) could not be decomposed, and the quality of the valuables recovered could be lowered.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to recover valuable materials from waste lithium ion batteries safely and efficiently.

  In order to achieve the above object, a waste lithium ion battery treatment apparatus of the present invention comprises a heating region for heating a waste lithium ion battery at 100 ° C. or higher and 250 ° C. or lower, and a waste lithium ion battery after heating at 300 ° C. or higher and 650 ° C. A heat treatment furnace having a roasting region for roasting at a temperature of less than or equal to ° C. is provided.

  According to the present invention, the waste lithium ion battery is heated at 100 ° C. or more and 250 ° C. or less in the heating region of the heat treatment furnace, and then the binder is roasted at 300 ° C. or more and 650 ° C. or less. Because it decomposes, there is no risk that the electrolyte will rapidly vaporize and the waste lithium ion battery will explode, and it will be safe to collect valuables from the waste lithium ion battery in the valuables recovery device at the later stage. it can.

  In the waste lithium ion battery processing apparatus, the heat treatment furnace may be a roller hearth kiln or a tunnel kiln. By using these furnaces, heating and roasting can be performed quickly and continuously.

  Moreover, the processing method of the waste lithium ion battery of the present invention comprises heating the waste lithium ion battery at 100 ° C. or more and 250 ° C. or less, and roasting the heated lithium ion battery at 300 ° C. or more and 650 ° C. or less. Features. According to the present invention, there is no risk that the electrolytic solution is rapidly vaporized and the waste lithium ion battery is ruptured, and a valuable material can be easily recovered from the waste lithium ion battery.

  In the treatment method of the waste lithium ion battery, by performing the heating and the roasting in a reducing atmosphere, the waste lithium ion battery directly charged without using a heat-resistant container or the like is heat-treated, The waste lithium ion battery can be carbonized to separate the carbonized mixture, and the electrolyte in the battery can be volatilized.

  As described above, according to the present invention, valuable materials can be recovered safely and efficiently from a waste lithium ion battery.

It is the schematic which shows one Embodiment of the processing apparatus of the waste lithium ion battery which concerns on this invention. It is the photograph of the lithium ion battery processed by the Example of the processing apparatus of the waste lithium ion battery which concerns on this invention. It is a photograph of the lithium ion battery processed by the comparative example of the processing apparatus of the waste lithium ion battery which concerns on this invention.

  Next, an embodiment of a processing apparatus and a processing method for a waste lithium ion battery according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a roller hearth kiln (hereinafter abbreviated as “kiln”) as a heat treatment furnace provided in a treatment apparatus for waste lithium ion batteries according to the present invention. This kiln 1 has a furnace front chamber 2, a heat treatment chamber 3, and a furnace rear chamber 4, and the heat-resistant containers C (C1 to C6) containing the received LIB are placed in the chambers 2 to 4 in this order. A transport device 5 for transporting by a roller is provided so as to pass.

  The heat-resistant container C is formed in a cylindrical shape with a lid having a heat-resistant temperature of at least 650 ° C. such as stainless steel (SUS304). The heat-resistant container C can accommodate a plurality of LIBs. Specifically, the LIB accommodated is a battery pack that accommodates a plurality of battery modules in a box-type housing, and a plurality of lithium ion battery cells are arranged in each battery module. Although not shown in the figure, the heat-resistant container C is provided with an exhaust pipe for exhausting internal combustion gas and a decompression means for releasing the pressure when the internal pressure increases.

  The furnace front chamber 2 includes a door 6 for switching between acceptance of the heat-resistant container C1 and shut-off from the outside by opening and closing, and an exhaust port 7 connected to an exhaust gas treatment facility (not shown).

  The heat treatment chamber 3 is divided into a heating area 3A and a roasting area 3B, and the doors 8 and 13 for switching between passage of the heat-resistant containers C2 and C4 and blocking of the outside by opening and closing, and the heat-resistant containers C3 and C4 are heated and Upper and lower heaters 9 and 10 serving as resistance heating elements for roasting, an air supply port 11, and an exhaust port 12 connected to the exhaust gas treatment facility in the same manner as the exhaust port 7 are provided. There is no particular boundary between the heating area 3A and the roasting area 3B, but the heating area 3A and the roasting area 3B are adjusted to 100 to 250 ° C. and 300 to 650 by adjusting the operating conditions of the upper and lower heaters 9, 10 and the like. Adjusted to a temperature range of ° C. Instead of the upper and lower heaters 9 and 10, a burner or the like that ejects high-temperature gas may be used.

  The furnace rear chamber 4 includes an exhaust port 14 connected to the exhaust gas treatment facility in the same manner as the exhaust port 7, and a door 15 for switching between passage of the heat-resistant container C <b> 5 and blocking of the outside by opening and closing. By opening and closing the doors 6, 8, 13, and 15 as described later, it is possible to prevent the exhaust gas in the heat treatment chamber 3 from leaking to the outside.

  Next, the operation of the processing apparatus having the above configuration will be described with reference to FIG.

  In the heat treatment chamber 3 of the kiln 1, the heating area 3 </ b> A is heated to 100 to 250 ° C. and the roasting area 3 </ b> B is heated to 300 to 650 ° C. by the upper and lower heaters 9 and 10. Air, oxygen, nitrogen or the like is supplied from the air supply port 11 as necessary. Here, by adjusting the exhaust amount from the exhaust port 12, the supply amount from the air supply port 11, and the like, the inside is controlled to a slightly negative pressure so that the exhaust gas in the heat treatment chamber 3 does not leak to the outside.

  The received LIB is accommodated in the heat-resistant container C1, the door 6 is opened and placed on the transfer device 5 inside the furnace front chamber 2 of the kiln 1, the door 6 is closed, the door 8 is opened and the heat-resistant container C2 is opened in the heat treatment chamber. 3 to the inside.

  The heat-resistant container C3 is heated at 100 to 250 ° C. in the heating region 3A, and the electrolyte contained in the LIB in the heat-resistant container C3 is volatilized. If it is this temperature range, rapid volatilization of electrolyte solution can be prevented and there is no danger that LIB will expand and burst. Furthermore, in order to prevent rapid volatilization of the electrolytic solution, it is preferable to raise the temperature to 100 to 250 ° C. at 5 ° C./min or less.

  Next, the heat-resistant container C4 reaches the roasting region 3B of 300 to 650 ° C., and the LIB in the heat-resistant container C4 is roasted. As a result, PVDF contained in LIB is decomposed and the resin portion becomes brittle.

  The inside of the heat-resistant container C4 is in a reducing atmosphere, and plastics such as a LIB resin casing housed in the heat-resistant container C4 are made of carbon, aluminum, lithium, cobalt, nickel, copper by carbonization. It is in a state separated from a material containing useful metals such as. Moreover, since the heat-resistant container C4 is heated at a temperature lower than the melting point (660 ° C.) of aluminum, the aluminum component in the LIB does not melt out.

  The gas generated by volatilization of the LIB electrolyte is discharged into the heat treatment chamber 3 together with the gas generated by the thermal decomposition of the combustible material such as plastic. These gases are flammable gases and can be taken out and reused as a heat source. Further, since the inside of the heat treatment chamber 3 is controlled to a negative pressure, the combustible gas or the like does not leak to the outside of the heat treatment chamber 3.

  Next, the door 13 is opened, the heat-resistant container C4 is accommodated in the furnace rear chamber 4, the door 13 is closed, the door 15 is opened, and the heat-resistant container C5 is taken out. The taken out heat-resistant container C6 is introduced into a valuable material recovery device (not shown) via the transfer device 5, and valuable materials such as aluminum, lithium, cobalt, nickel, and copper are recovered.

  The exhaust gas from the exhaust ports 7, 12, and 14 is treated in an exhaust gas treatment facility and rendered harmless, and then discharged outside the system.

  In the said embodiment, although the case where the roller hearth kiln 1 was employ | adopted was demonstrated, the tunnel kiln which utilizes a trolley | bogie as a conveying apparatus may be used, for example, and heating and roasting can be performed rapidly rapidly. it can. In addition to these furnaces, a furnace capable of continuously performing heating and roasting in the above temperature range can also be used.

  Even if the inside of the kiln 1 is an oxidizing atmosphere or the like, the inside of the heat-resistant container C4 is a reducing atmosphere, so plastics such as a LIB resin casing housed in the heat-resistant container C4 are carbonized by carbonization. It is preferable that the mixture is separated from a material containing a useful metal as a mixture. However, if the inside of the kiln 1 is a reducing atmosphere, the LIB is directly put into the kiln 1 and heat-treated without using the heat-resistant container C. Thus, LIB can be dry distilled to separate the carbonized mixture, and the electrolyte in the battery can be volatilized.

  Charge the charged square module lithium-ion battery (weight approx. 10kg, 25cm x 13cm height 10.5cm) into an 80L iron container (with exhaust pipe) with the lid closed and put it in a box-type electric furnace for 60 minutes. The temperature was raised to 200 ° C., held in that state for 1 hour, then heated to 450 ° C. in 60 minutes, and held in that state for 3 hours. As a result, as shown in FIG. 2, the lithium ion battery could be processed without causing an explosion.

Comparative example

  Only the roasting temperature of the example was changed, the temperature was raised to 450 ° C. in 60 minutes, and the state was maintained for 5 hours. As a result, the lithium ion battery exploded as shown in FIG. Since the shape of the recovered material was complicated by the explosion, the separation accuracy of useful metals decreased.

DESCRIPTION OF SYMBOLS 1 Roller hearth kiln 2 Furnace front room 3 Heat treatment room 3A Heating area 3B Roasting area 4 Reactor rear room 5 Transfer device 6 Door 7 Exhaust port 8 Door 9 Upper surface heater 10 Lower surface heater 11 Air supply port 12 Exhaust port 13 Door 14 Exhaust port 15 Door C (C1-C6) Heat-resistant container

Claims (4)

  It is provided with a heat treatment furnace having a heating region for heating a waste lithium ion battery at 100 ° C. or more and 250 ° C. or less and a roasting region for baking the waste lithium ion battery after heating at 300 ° C. or more and 650 ° C. or less. Waste lithium ion battery processing equipment.   The waste heat treatment apparatus according to claim 1, wherein the heat treatment furnace is a roller hearth kiln or a tunnel kiln. Heating the waste lithium ion battery at 100 ° C. or more and 250 ° C. or less,
A method for treating a waste lithium ion battery, wherein the waste lithium ion battery after heating is roasted at 300 ° C. or higher and 650 ° C. or lower.   The method for treating a waste lithium ion battery according to claim 3, wherein the heating and the roasting are performed in a reducing atmosphere.