JP7654354B2 - Method and device for processing bulky waste including combustible batteries - Google Patents

Description

The present invention relates to a method and device for processing bulky waste that contains combustible batteries, and in particular to a method and device for processing bulky waste that contains combustible batteries that can prevent ignition caused by the crushing of combustible batteries such as lithium ion batteries.

Generally, to process waste by incineration, melting, gasification, etc., the waste is first crushed to the desired size at a crushing facility, where it is then sorted into valuable materials, non-combustible materials, combustible materials, etc.

Specifically, the bulky waste is sent to, for example, a high-speed rotary crusher (hereinafter, simply referred to as the crusher), where it is crushed to, for example, 150 mm or less (85% or more by weight).

At this time, the garbage contains a large number of containers containing residual flammable materials, such as gas cylinders, spray cans, organic solvent containers, gasoline containers, and kerosene containers, as well as flammable batteries, such as lithium-ion batteries, which can ignite if cut (hereafter collectively referred to as hazardous materials). These hazardous materials should be separated and removed at the garbage collection stage, but in reality, a large number of hazardous materials are mixed into the garbage brought to bulky waste processing facilities.

For this reason, at bulky waste processing facilities, waste brought in is visually sorted and hazardous materials removed before it is put into the crusher. Measures are also taken to prevent fires and explosions in the unlikely event that hazardous materials are put into the facility by mistake. For example, various types of detectors such as ITV cameras, heat detectors, and flame detectors, as well as fire extinguishing water sprinklers, are installed as explosion and fire prevention measures. Furthermore, similar measures are also taken on the conveyor after the crusher.

The applicant has already proposed a solution to the fire prevention measures at such bulky waste treatment facilities using the technology disclosed in Patent Document 1. According to the technology disclosed in Patent Document 1, it is possible to prevent fires caused by ignition of combustible materials by detecting near-infrared rays that are generated before combustible materials ignite and spraying water from a water spray nozzle.

JP 2014-113213 A

Incidentally, in recent years, it has been common to find that lithium-ion batteries are included in waste disposed of at bulky waste disposal facilities. When these lithium-ion batteries are crushed in crushers at bulky waste disposal facilities, flammable electrolyte leaks from the lithium-ion batteries, and the mixture of the leaked flammable electrolyte and combustible materials can easily cause a fire, so immediate measures were needed.

However, the measures taken so far have mainly targeted explosions and fires caused by flammable gases in gas cartridges and the like, and have not been sufficient to prevent fires caused by leaks of flammable electrolyte in lithium-ion batteries, etc. As a result, when lithium-ion batteries are crushed into small pieces in high-speed rotary crushers, they are more likely to cause explosions and fires.

There are two ways that lithium-ion batteries can catch fire: (1) when they are cut, and (2) when flammable electrolyte leaks and sparks occur. (1) occurs inside the crusher, so existing fire prevention measures are still effective, but (2) can occur while the batteries are being transported to the next process, so sufficient measures have not been taken.

The bulk density of crushed bulky waste is low, and the probability that combustible materials will come into direct contact with the air increases dramatically, making them more flammable. If this mixture of combustible materials were to ignite due to leaked flammable electrolyte, the damage caused by the fire could be enormous.

The present invention has been made to solve the above-mentioned problems in the conventional technology, and has an objective of providing a method and device for processing bulky waste that makes it easy to detect ignition of small crushable waste that contains flammable batteries such as lithium ion batteries, prevents the fire from spreading to larger crushable waste, and effectively prevents ignition caused by the crushing of flammable batteries such as lithium ion batteries.

The present invention solves the above-mentioned problems by providing a method for treating bulky waste containing flammable batteries, the method comprising: a crushing process for crushing the bulky waste into crushed waste; a sorting process for receiving the crushed waste crushed by the crushing process and using a vibrated sieve to sort the crushed waste according to its size; a small crushed waste transporting process for transporting only the small crushed waste containing flammable batteries sorted by the vibrated sieve in the sorting process separately from other large crushed waste; a heat detection process for detecting heat generation or fire from the small crushed waste transported by the small crushed waste transporting process separately from the other large crushed waste; and a fire extinguishing process for extinguishing the fire separately from the other large crushed waste when heat generation or fire from the small crushed waste is detected.

The present invention also provides a bulky waste disposal device for disposing of bulky waste containing flammable batteries, comprising: a crushing means for crushing the bulky waste into crushed waste; a sorting means for receiving the crushed waste crushed by the crushing means and using a sieve vibrated by a vibrator to sort the crushed waste according to its size; a small crushed waste transporting means for transporting only the small crushed waste containing flammable batteries sorted by the sieve vibrated by the vibrator of the sorting means, separately from other large crushed waste; a heat detection means for detecting heat generation or fire from the small crushed waste transported by the small crushed waste transporting means separately from the other large crushed waste; and a fire extinguishing means for extinguishing the fire separately from the other large crushed waste when heat generation or fire from the small crushed waste is detected.

Here, the size of the small crushed waste containing the combustible batteries can be set to 50 mm or less.

In addition, the time for transporting the small crushed waste in the small crushed waste transport process or the small crushed waste transport means can be set to a predetermined time or longer.

In addition, the conveying speed of the small crushed waste conveying process or the small crushed waste conveying means can be made variable.

According to the present invention, it is possible to easily detect ignition of small crushed waste containing combustible batteries such as lithium ion batteries, and to prevent the fire from spreading to larger crushed waste, thereby effectively preventing ignition phenomena caused by the crushing of combustible batteries such as lithium ion batteries.

FIG. 1 is a cross-sectional view showing the overall configuration of a bulky waste treatment facility in which an embodiment of the present invention is adopted. Flowchart showing the mechanism by which a lithium-ion battery catches fire

The following describes in detail the embodiments of the present invention with reference to the drawings. Note that the present invention is not limited to the contents described in the following embodiments. Furthermore, the components in the embodiments described below include those that a person skilled in the art can easily imagine, those that are substantially the same, and those that are within the so-called equivalent range. Furthermore, the components disclosed in the embodiments described below may be appropriately combined or appropriately selected for use.

Figure 1 shows the overall configuration of a bulky waste treatment facility that employs an embodiment of the present invention.

Bulky waste 10, which contains flammable batteries 12 such as lithium ion batteries, is fed through a bulky waste inlet and transported to a high-speed rotary crusher 22 (hereinafter also referred to as crusher 22) by a feed conveyor 20. Crushed waste 14, for example, crushed to 150 mm or less (85% or more by weight), is sorted by a sorter 24 having a sieve 24B of, for example, 50 mm, which is vibrated by a vibrator 24A, and small crushed waste 16 containing flammable batteries 12 falls to the entrance side of a crushed material conveyor 26. On the other hand, large crushed waste 18, which contains combustibles and contains almost no flammable batteries 12, is left on the sieve 24B of the sorter 24 and transported, and then falls onto the crushed material conveyor 26.

In other words, after the sorting machine 24 separates small crushed waste 16 from large crushed waste 18, the small crushed waste 16 and large crushed waste 18 are mixed again and transported by the crushed waste transport conveyor 26.

The combustible batteries 12 are damaged by impact from the hammer of the crusher 22, collision contact with metal blocks, or dropping or collision. That is, as shown in FIG. 2, combustible batteries 12, such as lithium ion batteries, that are mixed into bulky waste 10 may break the separator of the battery components during the crushing process due to mechanical factors such as strong impact or pressure, or being pierced by a sharp object such as scissors or a blade, causing the flammable electrolyte 13 to leak and ignite when sparks come into contact with this electrolyte 13. Alternatively, the positive and negative electrodes may short-circuit, causing a large current to flow through the short-circuited part, generating a large amount of heat, which may then lead to thermal runaway and ignition.

When the combustible battery 12 is, for example, a lithium ion battery, the shape can be, for example, (1) a cylinder with a diameter of 18 mm and a length of 65 mm, (2) a square shape with a thickness of 5 mm, a width of 40 mm, and a height of about 50 mm, or a square shape with a length of 17 mm, a width of 40 mm, and a height of about 110 mm, or (3) a laminate shape with a size almost the same as the square shape, or a length of 250 mm, a width of 140 mm, and a height of about 9 mm. Most of the shapes are 50 mm or less after crushing, so after the cases housing the combustible batteries 12 are crushed by the crusher 22, the small crushed waste 16 containing the combustible batteries 12 can be collected by the 50 mm sieve 24B of the sorter 24. The collected small crushed waste 16 contains little combustible material, so even if the combustible battery 12 explodes or catches fire, the fire can be prevented from spreading.

The collected small crushed garbage 16 of 50 mm or less is sent to the next process on a crushed material conveyor 26 made of iron or a flame-retardant rubber belt, but only small crushed garbage 16 of 50 mm or less is sieved out by a sieve 24B and falls to the entrance side of the crushed material conveyor 26. A heat source detector 30 that detects near-infrared rays, for example, as in Patent Document 1, is installed near the entrance side of the crushed material conveyor 26 where the small crushed garbage 16 falls, and heat generation and ignition can be detected. Therefore, there is little large flammable material around the collected small crushed garbage 16 of 50 mm or less, and by using a non-flammable iron or flame-retardant rubber belt for the crushed material conveyor 26 that transports the collected material, the spread of fire can be prevented even if the ignitable battery 12 explodes or ignites.

Furthermore, the transport speed of the crushed material transport conveyor 26 is adjusted so that the transport time is, for example, 30 seconds to 1 minute, taking into consideration the ignition time of the flammable batteries 12 (approximately 30 seconds to 1 minute). At this time, by making the transport speed of the crushed material transport conveyor 26 variable, the transport time can be easily adjusted.

Sprinkler nozzles 34 connected to fire extinguishing sprinkler equipment 32 are installed in front of and behind the heat source detector 30, and when heat generation or fire is detected by the heat source detector 30, water is sprayed from the sprinkler nozzles 34.

The heat source detectors 30 can be installed, for example, at intervals of about 2.5 m on the crushed material transport conveyor 26, with about 10 units installed, but it is particularly preferable to install them just below the sorter 24, before the small crushed waste 16 and large crushed waste 18 are mixed.

The water spray nozzle 34 can spray 20 liters of water per meter of conveyor, for example, at 10 liters per minute.

As already mentioned, in the past, combustible materials and ignitable batteries such as lithium ion batteries were transported together, but in the present invention , immediately after crushing, small crushed waste containing ignitable batteries is separated from large crushed waste containing a large amount of ignitable materials, and heat generation or fire is detected during the transport process of the small crushed waste, so that small fires in ignitable batteries can be reliably detected without being hindered by the large crushed waste. Therefore, it is possible to quickly extinguish small fires before they become large.

In the embodiment of the present invention, the ignitable battery is a lithium ion battery, but the ignitable battery is not limited to this, and it is possible to use lithium batteries other than lithium ion batteries, or other batteries. The crusher 22 is not limited to a high-speed rotary crusher, and the present invention can be applied to a low-speed two-shaft crusher, for example. The sorting machine 24 is not limited to a vibrating screen, and the heat source detector 30 is not limited to one that detects near-infrared rays. The positions and number of the heat source detector 30 and the watering nozzles 34 are also not limited to the embodiments of the present invention.

10... Bulky waste 12... Combustible batteries (lithium ion batteries)
Reference Signs List 13: Electrolyte 14: Crushed waste 16: Small crushed waste 18: Large crushed waste 20: Supply conveyor 22: (High-speed rotating) crusher 24: Sorting machine 24A: Vibrator 24B: Sieve 26: Crushed material transport conveyor 30: Heat source detector 32: Fire extinguishing water sprinkler system 34: Water sprinkler nozzle

Claims (8)

A method for treating bulky waste containing ignitable batteries, comprising:
A crushing step of crushing the bulky waste into crushed waste;
A sorting process for receiving the crushed waste crushed by the crushing process and sorting the crushed waste according to its size using a vibrated sieve ;
a small crushed waste conveying process in which only the small crushed waste containing the combustible batteries sorted by the vibrated sieve in the sorting process is conveyed separately from other large crushed waste;
A heat detection process for detecting heat generation or ignition from the small crushed waste transported by the small crushed waste transport process separately from the other large crushed waste;
a fire extinguishing step for extinguishing the small crushed waste separately from the other large crushed waste when heat generation or ignition from the small crushed waste is detected;
1. A method for treating bulky waste containing ignitable batteries, comprising: The method for treating bulky waste containing combustible batteries according to claim 1, characterized in that the size of the small crushed waste containing the combustible batteries is 50 mm or less. 3. The method for treating bulky waste containing ignitable batteries according to claim 1, wherein the transport time of the small crushed waste in the small crushed waste transporting step is equal to or longer than a predetermined time. 4. The method for treating bulky waste containing ignitable batteries according to claim 1 , wherein the transport speed of the small crushed waste transporting step is variable. A bulky waste treatment device for treating bulky waste including ignitable batteries,
A crushing means for crushing the bulky waste into crushed waste;
A sorting means for receiving the crushed waste crushed by the crushing means and sorting the crushed waste according to its size using a sieve vibrated by a vibrator ;
A small crushed waste conveying means for conveying only the small crushed waste containing the combustible batteries separated by the sieve vibrated by the vibrator of the sorting means, separately from other large crushed waste;
A heat detection means for detecting heat generation or ignition from the small crushed waste transported by the small crushed waste transport means separately from the other large crushed waste;
a fire extinguishing means for extinguishing a fire separately from the other large crushed waste when heat generation or ignition from the small crushed waste is detected;
A treatment device for bulky waste containing ignitable batteries, comprising: 6. The treatment device for bulky waste containing ignitable batteries according to claim 5 , wherein the size of the small crushed waste containing the ignitable batteries to be separated is 50 mm or less. 7. The treatment device for bulky waste containing ignitable batteries according to claim 5 or 6 , characterized in that the time taken for the small crushed waste to be transported by the small crushed waste transporting means is equal to or longer than a predetermined time. 8. The treatment device for bulky waste containing ignitable batteries according to claim 5 , wherein the transport speed of the small crushed waste transport means is variable.

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