JP2002177935A - Treatment method and treatment equipment for waste fluorescent tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a treatment method and treatment equipment for waste fluorescent tubes capable of safely and stably reducing the amount of the mercury remaining at crushed glass granular pieces 17 to sufficiently low value, recycling glass, mercury, fluorescent powder, etc., and making treatment in a large amount. SOLUTION: 1 mercury-containing fluorescent powder in the waste fluorescent tubes 2 opened at the sections of both ends of the glass tubes is subjected to primary cleaning by blowing off the powder by jetting of compressed gas and thereafter the glass tubes are crushed to the crushed glass granular pieces 17. The glass tubes are then picked by pickling equipment 18 as a secondary cleaning process step, by which the trace residual mercury remaining at the glass is removed. The waste gas 13 in the primary cleaning is treated with a powder separator 15, fluorescent powder treatment equipment 23 and mercury capturing equipment 31, by which the fluorescent powder 29 and the mercury 28 are recovered. The hydrochloric acid treatment of an adequate concentration is effective in the pickling equipment 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the treatment of waste fluorescent tubes, and more particularly, to the collection and recovery of waste fluorescent tube glass.
Treatment and treatment of mercury and fluorescent substances adhering to the inner surface of the waste fluorescent tube, and gaseous mercury in the waste fluorescent tube
The present invention relates to a method and an apparatus for collecting.

[0002]

2. Description of the Related Art At present, fluorescent tubes (fluorescent discharge tubes) widely used as efficient lighting lamps belong to low-pressure mercury lamps. In this fluorescent tube, a fluorescent substance is applied to the inner surface of a cylindrical glass tube, and a tungsten double filament electrode having a protective film such as barium oxide formed on the surface is attached to both ends, and the inside of the glass tube is evacuated. A small amount of mercury and argon gas are sealed. In such a fluorescent tube, electric current is applied to the filament electrodes at both ends, and a voltage is applied between the two electrodes to cause discharge within the tube, so that far ultraviolet rays are emitted from the mercury gas in the tube, and the far ultraviolet rays are applied to the inner wall of the tube. The emitted fluorescent substance is irradiated to emit light. The amount of mercury used in this fluorescent tube is small. For example, a standard product having a length of 1.2 m has a total weight of 240
Only 25 mg of mercury per g is enclosed. However, when such a fluorescent tube is discarded after being used, harmful mercury remains in the tube in a gaseous state or adsorbed on the inner wall of the fluorescent tube or a fluorescent material. Therefore, if a large amount of waste fluorescent tubes are crushed and discarded, a large amount of mercury will be released, harming the environment. Therefore, conventionally, when disposing of the waste fluorescent tube, a method has been proposed for preventing the occurrence of pollution particularly by mercury and for safely and efficiently collecting mercury.

Heretofore, when treating a used waste fluorescent tube, a general main method has been a wet treatment method and a dry treatment method.

[0004] Wet treatment method: A waste fluorescent tube is crushed and washed with water using a mercury solidifying agent such as sulfide or tonalium carbamate. The floc thus generated is packed in concrete and disposed of. However, in this method, mercury cannot be recovered, and wastewater treatment after washing is expensive.

[0005] Dry treatment method: As a main method, a waste fluorescent tube is crushed by a crusher, a mercury adsorbent is mixed therein, and a mixture of the obtained pulverized material and the mercury adsorbent is transported to a mercury mine. Therefore, mercury is recovered. However, this method has a disadvantage that the cost of transporting the mixture is increased.

On the other hand, the following methods have been proposed to solve the above-mentioned problems. The first example is a method in which a waste fluorescent tube is crushed in a hermetically sealable container, and then roasted, and mercury generated in such a process is collected and recovered by an appropriate method (hereinafter, referred to as a method). , "Crushing and roasting method"). In the second example, a sealable container is previously filled with a mercury solution having the ability to dissolve and absorb mercury, and the waste fluorescent tube is crushed in the closed container to transfer and separate mercury into the mercury solution. When the gaseous mercury floats and escapes in the solution during crushing, it is treated after collecting and storing the gas in the upper closed chamber. In this method, mercury is recovered from the generated mercury-containing waste liquid by an appropriate method, and the stored gaseous mercury is separately treated (hereinafter, referred to as “closed wet crushing method”). The third example is a method similar to the second example, in which the gaseous mercury mixed into the suction air by crushing the waste fluorescent tube in the air atmosphere of the suction area is passed through the mercury solution. And then absorb and remove it in the solution, and subsequently immerse the crushed waste fluorescent tube in the mercury solution to collect and remove mercury (hereinafter referred to as “atmospheric suction crushing / wet treatment method”). ).

In addition to the above examples, the bases at both ends of the waste fluorescent tube are removed, and an air flow is introduced into the glass of the waste fluorescent tube having both ends opened without breaking the glass tube. A method of blowing away the fluorescent substance and mercury is considered (hereinafter, referred to as "air flow cleaning method").

First Example: As the "crushing and roasting method", Japanese Patent Application Laid-Open No. 9-49625 discloses the following method. The waste fluorescent tube is crushed in an air flow such as air in a sealable container. Gaseous mercury generated during the crushing of the used fluorescent tube is removed by adsorption on activated carbon. On the other hand, the crushed pieces are roasted in a rotary kiln. The mercury contained in the waste gas generated in the roasting process is cooled and collected as liquid mercury, and gaseous mercury still remaining in the waste gas is adsorbed and removed by activated carbon. The solid residue generated by heating and roasting in a rotary kiln is treated by a sieving apparatus to separate it into glass dust and die dust (hereinafter referred to as “prior art 1”). According to this method, mercury, glass, and the like can be recovered as resources, and only the activated carbon to which mercury is adsorbed is transported to the mercury mine to request processing, and further, wastewater treatment of the treated water is unnecessary. However, in the “crushing and roasting method” as in the prior art 1,
Only a small amount of mercury of about 25 mg per waste fluorescent tube is sealed, and most of the material weight is a glass tube, which is transported to the incinerator and the entire material is incinerated. This will result in a great waste of incinerated fuel consumption.

As a second example: Japanese Patent Application Laid-Open No. H6-154641 discloses the following method as "closed wet crushing method". The upper side of the sealed tank filled with the mercury solution is divided into two by a vertical partition, and both divided chambers are made to freely move from the lower end of the partition with the mercury solution in the lower closed tank. Then, the waste fluorescent tube is fed into the division chamber on one side of the partition, and is crushed in the division chamber (crushing chamber) on the other side. The gaseous mercury generated during the crushing of the waste fluorescent tube accumulates in a sealed space between the mercury solution above the crushing chamber and the ceiling of the crushing chamber. On the other hand, the crushed waste fluorescent tubes are settled and deposited at the lower part of the mercury solution tank main body. Gaseous mercury that has accumulated in the sealed space is appropriately extracted through an exhaust pipe and detoxified. Also, from the drain pipe at the bottom of the mercury solution tank main body, the mercury solution containing mercury removed from the surface of the crushed glass pieces and the like is withdrawn, adjusted to pH, subjected to a predetermined treatment, dehydrated, and sludge and filtered. The mercury concentration in the water is checked and treated (hereinafter referred to as "prior art 2"). Prior art 2
According to the method described above, mercury can be detoxified by a single device, and wasteful incineration and fuel consumption as in the above-mentioned "crushing and roasting method" can be avoided. However, the operation of the "sealed wet crushing method" using a device having a large amount of waste fluorescent tube processing capacity requires complicated process management, increases operating costs, and poses a problem in economy.

Third example: "Atmospheric suction crushing / wet processing method"
JP-A-2000-303125 discloses the following method. The waste fluorescent tube is damaged in the suction area inside the machine where the waste fluorescent tube is broken in the atmosphere, and the enclosed space is dropped from the suction area and dropped and pressed into the dissolution tank containing the mercury solution. Then, the broken waste fluorescent tube is immersed and the mercury dissolving solution is caused to flow therein to dissolve the mercury adhering to its inner surface, and then the mercury dissolving solution containing mercury is passed through a mercury adsorbent to remove the mercury. It is adsorbed and removed, and mercury is separated and recovered from the mercury adsorbent. The mercury solution from which mercury has been removed and separated is circulated and reused. The washed damaged fluorescent tube is discharged by a carry-out conveyor leading to the bottom of the dissolution tank. The gaseous mercury generated from inside the tube when the waste fluorescent tube was damaged and mixed into the suction air was
It is collected in the space above the liquid surface in the dissolution tank together with the suction air. The mercury-containing air collected in this space is discharged into a mercury solution to remove mercury (hereinafter referred to as “prior art 3”). According to the method of Prior Art 3, a large amount of waste fluorescent tubes can be quickly processed, and mercury can be safely recovered. However, in the method of Prior Art 3, it is difficult to stably and sufficiently reduce the concentration of mercury remaining on the damaged fluorescent tube after processing / recovery, and to achieve both a reduction in the amount of residual mercury and a processing efficiency. It is difficult.

As described above, in addition to the first to third examples exemplified in the prior arts 1 to 3, the following methods can be considered as the "air washing method". That is, by removing the base of the waste fluorescent tube in the closed container, then introducing a high-speed airflow from one end into the waste fluorescent tube from which the base has been removed, and ejecting the high-speed airflow from the other end. Another possible method is to blow off gaseous mercury in a waste fluorescent tube and fluorescent substances and mercury adhering to the inside of the tube. At that time, the inside of the sealed container is suctioned to separate and remove mercury and fluorescent substances contained in the waste gas by an appropriate method.
Collect mercury. Also, the process of collecting glass from which mercury and fluorescent substances have been removed is simple. This method is particularly suitable for treating a large amount of waste linear fluorescent tubes efficiently. However, in this method, in regard to the removal of mercury adhering to the interior of the waste fluorescent tube, in particular, as in Japan, from the viewpoint of meeting strict environmental tolerance standards, the amount of mercury remaining in the tube is stably and sufficiently reduced. There is a problem with controlling.

[0012]

As described above, in the conventional waste fluorescent tube treatment technology, the collection and treatment of glass,
In addition, when treating mercury and fluorescent substances adhering to the inner surface of a waste fluorescent tube, and gaseous mercury in the waste fluorescent tube, there is no waste in the transportation cost of the waste fluorescent tube or the fuel cost required for incineration, or a single device. However, operating costs are high and there is a problem in economics, it is difficult to achieve both a reduction in the amount of residual mercury adhered in the damaged fluorescent tube and maintenance of processing efficiency, or There is a problem that it is difficult to stably purify the amount of residual mercury adhering to a level that satisfies Japanese environmental standards.

Therefore, the present inventors have as an object to solve the present invention that a large amount of waste fluorescent tubes can be efficiently treated and the amount of mercury remaining on the crushed glass is eluted according to Japanese environmental standards. 0.005 mg / l or less, and a technique to stably maintain the level was developed. An object of the present invention is to provide a large amount of waste fluorescent tubes efficiently at a low cost and to solve the problem of mercury leakage and residue, and in particular to stably meet the mercury elution standard in Japan. An object of the present invention is to provide a processing technique for a waste fluorescent tube that can contribute to environmental conservation.

[0014]

Means for Solving the Problems The present inventors have conducted extensive tests and studies on the above-mentioned problems.

First, part of the mercury sealed inside the waste fluorescent tube is sealed in a gaseous state, and the rest is mainly adhering to the inner wall of the waste fluorescent tube in a state of being mixed or adsorbed into the fluorescent powder and remaining. It was noted that a small portion of was adhered to the inner wall of the tube. Then, gaseous mercury is contained in a sealable container having a sufficiently large volume compared to the volume of the waste fluorescent tube,
By processing the open part of the waste fluorescent tube to the atmosphere in the sealable container, the gaseous mercury is released into the sealable container, and subsequently, in the same sealable container. The high-speed airflow is caused to flow from one end of the both ends of the waste fluorescent tube, which is pre-opened, to the other end, and the fluorescent powder adhered to the inner wall of the tube is mixed and adsorbed therewith. The mercury is blown off and removed (the above step is hereinafter referred to as “first step”). Here, in the first half of the first step, as the processing of the open portion for the waste fluorescent tube, the glass tube is formed at right angles to the tube length direction so as to remove the bases at both ends of the linear waste fluorescent tube. Cut,
On the other hand, for a ring-shaped waste fluorescent tube, the glass tube is cut at a right angle in the vicinity of both sides of the base, and the circumferential direction is cut into two or three equal parts according to the size of the ring body diameter. The glass tube after cutting should be close to a straight line. By the above-described first step, most of the sealed mercury in the waste fluorescent tube is blown off and removed by the jet high-speed gas in the sealable container (hereinafter, referred to as “sealed container”).

According to the mercury removal method of the first step, the following advantages are obtained. (1) Since both gaseous mercury in the waste fluorescent tube and mercury mixed with and adhered to the fluorescent powder are continuously discharged into the same closed container, the gas in the lower process in the closed container is The waste gas containing mercury is separated from the powder containing fluorescent powder. Therefore, a high-level and high-efficiency mercury removal process can be applied by a treatment process specialized for waste gas treatment. (2) Since the glass part of the waste fluorescent tube after the removal of mercury is in a shape close to the original shape without being crushed or crushed, handling during transfer / transportation to the next second step is extremely easy. Yes, it contributes to the construction of a large and efficient waste fluorescent tube treatment process.

Next, following the first step, the following second step is provided. The reason is as follows. That is, the present inventors set various test conditions in the first step and investigated the amount of mercury remaining on the inner wall of the glass tube after the first step treatment. The test conditions were selected, in particular, as the high-speed gas injection conditions, the gas flow rate from the compressed air nozzle,
Various conditions of the glass tube length and the glass tube curvature were tested by changing the pulse emission conditions of the compressed air. As a result, the amount of mercury remaining on the inner wall of the glass tube is
0.0 which is the mercury elution standard value according to the notification of the Environment Agency No. 13.
A measured value of mercury elution at a concentration exceeding this value was found for 05 mg / l. For example, 0.031 mg / l to 0.091 mg / l were measured. The present inventors,
Based on this result, it was determined that it was necessary to perform an operation for removing trace mercury remaining on the inner wall of the glass tube from the glass tube subjected to the mercury removal treatment in the first step.

As described above, the treatment in the first step is not always sufficient, but the treatment in the step removes most of the mercury in the waste fluorescent tube, and the residual amount is very small.
That is, it was found that the amount of mercury contained in the fluorescent powder and considered to remain fixed on the inner wall of the glass tube was very small.

Therefore, it is appropriate to employ a wet method as a method for removing such a very small amount of residual mercury, and the concentration of the remaining mercury to be removed (concentration determined by the amount of dissolved mercury). Focusing on small, the present inventors,
The glass tube whose both ends were opened and processed in the first half of the first step was crushed into fine particles having an appropriate size (grain size), and mercury was removed by a wet method. Here, to crush into fine pieces of appropriate size (granularity)
It means that the glass has a particle size suitable for collection and reuse, and that the glass is crushed within a particle size range in which a target amount of mercury removal by a wet method is sufficiently achieved. That is, since the remaining amount of mercury to be removed by this wet method is small, it is determined that the glass tube may be finely crushed,
Therefore, giving priority to the recycling of glass,
It was noted that the particles could be crushed small to a particle size advantageous to this. For example, when considering recycled glass, lightweight aggregates, tiles, furniture, and the like as glass recycling resources, it is desirable that the glass be as fine as possible. From about 10
It was found that crushing to a particle size of not more than mm was sufficient.

The present inventors further conducted a mercury removal test by a wet method for a case where the glass was finely crushed to some extent. As a result, the following findings were obtained. That is, conventionally, for example, as described in Prior Art 1, it has been proposed to use nitric acid having a concentration of 5% or more as a mercury solution (see JP-A-2000-303125, paragraph 0062). On the other hand, the present inventors have proposed that the liquid for removing mercury contained in the fluorescent powder and considered to be fixed and remaining on the glass fine particles is not limited to nitric acid, but may be any other suitable concentration. , For example, about 1 to 2N hydrochloric acid was found to be effective.

The mechanism of the action of hydrochloric acid for removing mercury from such fine glass particles is not always clear. However, according to experiments by the present inventors, when a predetermined amount of the fluorescent powder is added to a predetermined amount of water and suspended and allowed to stand, the fluorescent powder precipitates, whereas the fluorescent powder is diluted with dilute hydrochloric acid. When the suspension was added and suspended, generation of some bubbles was observed, and precipitation of the fluorescent powder was not observed. From this result, the fluorescent substance reacts with hydrochloric acid and dissolves,
It is presumed that hydrochloric acid exerted the effect of removing mercury because trace amounts of mercury adhering to the glass or the fluorescent substance became easier to elute.

As described above, in reducing the amount of mercury remaining on the crushed glass, which is a problem to be solved in the present invention, to sufficiently clear the environmental standard of 0.005 mg / l or less, handling It has been found that an acid such as hydrochloric acid, which is easier than nitric acid, is effective, and has become more desirable for solving this problem.

Based on the above findings, the present inventors have found that, as a second step, fine particles having an appropriate particle size range are applied to the glass tube after the mercury removal treatment in the first step using a crusher. The present inventors have conceived of a method of subjecting the glass tube to a crushing treatment and washing the obtained fine glass particles with an acid to remove the mercury fixed and remaining on the inner wall of the glass tube together with the fluorescent powder.

The present invention has been made based on the above-mentioned several findings, and its gist is as follows.

The method for treating a waste fluorescent tube according to the first aspect of the present invention comprises the following steps (a) and (b): step (a): both ends of a linear waste fluorescent tube in a sealable container. Remove the base part. By injecting compressed gas from one end of the glass tube portion of the obtained waste fluorescent tube toward the other end, gaseous mercury in the waste fluorescent tube and the inside of the glass tube portion, but actually Is attached to or adhered to the inner wall of the tube, but the fluorescent substance and mercury are blown and discharged into the sealable container. At the same time, the atmosphere inside the sealable container is sucked by a blower or the like. The waste gas sucked in this way contains the gaseous mercury, the fluorescent substance and mercury mixed in the fluorescent substance, and separates and removes these from the waste gas. b): crushing the glass tube portion treated in the step (a). Pickling the obtained crushed glass particles to separate and remove the fluorescent material remaining in the crushed glass particles and mercury mixed in the fluorescent material. is there.

The method for treating a waste fluorescent tube according to the second aspect of the present invention is characterized in that it is performed as follows in the first aspect of the present invention. That is, the above step (a)
In the step of separating and removing gaseous mercury contained in the waste gas sucked from the inside of the sealable container, the fluorescent substance and mercury mixed in the fluorescent substance, The gas is treated with a cyclone to recover the fluorescent material containing mercury. A step of obtaining the fluorescent substance and mercury by treating the collected fluorescent substance with a vacuum heating device and a mercury vapor condenser, and discharging the mercury-containing exhaust gas after the cyclone treatment with a mercury dry adsorption method or This is a process in which mercury is separated and removed from the exhaust gas by a combination of a dry adsorption method and a wet oxidation absorption method.

According to a third aspect of the present invention, there is provided a method for treating a waste fluorescent tube according to the first or second aspect.
It is characterized by performing as follows. That is,
When crushing the glass tube portion in step (b), 15m
The crushed glass particle pieces are prepared so that the particle size distribution is such that the glass particle pieces of m or less account for 95 mass% or more. The crushed glass particle pieces prepared to have such a particle size are treated according to the step (b). The crushed glass particles thus prepared and treated are used for recycled glass, lightweight aggregate, tile or furniture.

A method for treating a waste fluorescent tube according to a fourth aspect of the present invention is characterized in that the method according to any one of the first to third aspects is performed as follows. That is, hydrochloric acid, nitric acid or sulfuric acid is used as the acid used for pickling the crushed glass particles in the step (b).

A method for treating a waste fluorescent tube according to a fifth aspect of the present invention is characterized in that the method according to any one of the first to fourth aspects is performed as follows. That is, prior to removing the bases at both ends of the linear waste fluorescent tube in step (a), one or more holes are formed through the tube wall of the waste fluorescent tube.

A method for treating a waste fluorescent tube according to a sixth aspect of the present invention is characterized in that the method according to any one of the first to fifth aspects is performed as follows. That is, in step (a), the shape of the waste fluorescent tube to be treated is an annular tube, and prior to removing the base portion, the annular tubular waste fluorescent tube is equally divided into two or more in the circumferential direction,
Then, the base portion is removed.

A waste fluorescent tube processing apparatus according to the invention of claim 7 comprises the following devices (a) to (f): device (a): for loading the waste fluorescent tube into a sealable container. (B): a cutting machine for cutting and removing the base portion of the waste fluorescent tube in the sealable container, and a cutting machine for cutting and removing the base portion of the waste fluorescent tube in the glass tube portion of the waste fluorescent tube. Waste fluorescent tube provided with a gas injection nozzle for injecting a compressed gas for blowing away and purifying residual mercury and a fluorescent substance, and a crusher for crushing the glass tube portion whose inside has been cleaned Crushing device, device (c): at the time of cutting and removing the base portion and at the time of injecting the compressed gas, waste gas containing mercury and a fluorescent substance blown and discharged from the inside of the waste fluorescent tube into the sealable container. Aspirate and from the aspirated waste gas Dust separation device for separating and removing silver and fluorescent material, Device (d): Fluorescent powder treatment for separating and collecting mercury and fluorescent powder respectively from mercury-containing fluorescent powder separated by the above dust separation device Apparatus, Apparatus (e): a mercury collecting apparatus for collecting mercury from exhaust gas after mercury and fluorescent powder have been removed by the dust separation apparatus, and apparatus (f): a crushing apparatus for waste fluorescent tubes Characterized by being equipped with an acid washing device for washing the crushed glass particles crushed with the above with dilute acid and separating and removing fluorescent substances and mercury remaining in the crushed glass particles. It is.

The waste fluorescent tube processing apparatus according to the invention of claim 8 is the invention according to claim 7, wherein the waste fluorescent tube crushing device is further provided with the closed fluorescent tube before removing the base portion of the waste fluorescent tube. The present invention is characterized in that a gas burner for forming a through hole in the tube wall of the waste fluorescent tube in a possible container is provided.

According to a ninth aspect of the present invention, there is provided the waste fluorescent tube processing apparatus according to the seventh or eighth aspect,
It is characterized in that the crushed glass particle piece pickling apparatus is a pickling apparatus using diluted hydrochloric acid, diluted nitric acid or diluted sulfuric acid.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a method and an apparatus for treating a waste fluorescent tube according to the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram of a processing flow of a waste fluorescent tube for explaining an embodiment of the present invention, and FIGS. 2 to 4 are detailed views of each divided part when FIG. 1 is divided into three parts by a chain line. .

In these figures, reference numeral 1 denotes a waste fluorescent tube crushing device, which carries a waste fluorescent tube 2 into a container (referred to as a closed container) 4 which can be closed by a carry-in device 3. Inside the closed vessel 4, an opening burner 5, a cutting machine 6, a compressed gas injection nozzle 7 and a crusher 8 are provided. First, a hole penetrating through the wall of the waste fluorescent tube 2 carried into the container 4 by the opening burner 5 is opened to break the airtightness of the waste fluorescent tube 2. The internal pressure of the fluorescent tube is usually as low as about 10 ⁻⁵ atm, and mercury exists in a gaseous state. Therefore, a part of the mercury sealed therein is released into the container 4 as gaseous mercury 40 due to the hermetic destruction, and the remaining part is liquefied. Next, the base part 10 of the waste fluorescent tube 2 is cut and removed by the cutting machine 6, and the removed base part 10 is removed.
Recovers aluminum, brass and lead glass from this in a conventional manner (39). However, when the shape of the waste fluorescent tube 2 is a straight tube, the base portions 10 at both ends are removed to open both end cross sections. On the other hand, when the tube shape is a ring tube, the base portion 10 is cut and removed, and the diameter of the ring body is reduced. 2 or 3 of circumference depending on the size
After the tube is cut into equal lengths by equal cutting, the cross sections at both ends are opened. The compressed gas 9 is blown from the injection nozzle 7 into the glass tube 11 from one end of the glass tube 11 whose both end cross sections are opened, and the compressed gas 9 is blown out from the other end of the glass tube 11. 11 Blow away the fluorescent powder adhering or sticking to the inner wall. This fluorescent powder contains mercury liquefied at the time of drilling holes in the waste fluorescent tube 2 as described above. This fluorescent powder containing mercury 1
In order to efficiently blow off and remove 2 from the inner surface of the glass tube, it is effective and desirable to radiate the compressed gas 9 injected from the injection nozzle 7 in a pulse shape. The mercury-containing fluorescent powder 12 released and removed from the inner wall of the glass tube 11 into the closed container 4 is mixed into the waste gas 13 together with the gaseous mercury 40 released into the closed container 4 described above. Is sucked from the closed container 4 to the dust separation device 15 through the suction gas pipe 14.

The clean glass tube 11 ′ whose inside has been cleaned in this way is fed into the crusher 8. The clean glass tube 11 'sent to the crusher 8 is crushed. In crushing, it is desirable to determine the crush size according to the scheduled post-treatment process of the clean glass tube 11 '. That is,
In the present invention, the glass tube 11 by the compressed gas 9 is used.
As a result of performing internal cleaning tests under various conditions, it is difficult to stably clear the environmental standards to be satisfied at the time of glass recycling processing only by cleaning by injection of the compressed gas 9; The clean glass tube 1
1 ′ is that it is necessary to add a step of removing a trace amount of mercury after crushing this,
In addition, clearing the environmental standards by a post-processing process, and considering the case where the recycling of the ground glass is scheduled, to make the environmental standards clear and necessary, and to be able to recycle the ground glass as efficiently as possible,
It is desirable to decide after considering. From this viewpoint, in the present invention, it is desirable to select an appropriate pickling process using a dilute acid as a post-treatment process of the clean glass tube, and the crushed glass particles of the clean glass tube 11 ′ by the crusher 8. The size 17 is desirably processed so that glass grain pieces of 15 mm or less occupy 95 mass% or more. The crushed glass particles 17 thus crushed are conveyed to the pickling device 18.

In the above-described waste fluorescent tube crushing apparatus 1, the sealed container 4 is designed so that the waste gas 13 does not leak to the outside of the container 4 to cause mercury contamination, and that the efficiency of suction of the waste gas 13 from the container 4 is reduced. It is only necessary that the container satisfy the condition that it does not decrease.
The loading of the waste fluorescent tube 2 into the sealed container 4 and the removal of the crushed glass particles therefrom need not be limited to continuous, but may be batch loading and batch discharging. Similarly, the timing at which the waste gas 13 is suctioned and removed from the closed container 4 may be discontinuous at appropriate times by the open / close valve 16 provided in the suction gas pipe 14. In addition, the provision of the opening burner 5 contributes to the improvement of the processing capacity of the waste fluorescent tube 2. The opening burner 5 is preferably, for example, a hydrogen burner. However, by providing the function of the opening burner 5 to the cutting machine 6, the equipment of the opening burner 5 may be omitted.

The waste gas 13 formed in the closed vessel 4 of the waste fluorescent tube crusher 1 is sucked by the blower 21 and enters the dust separator 15 through the suction gas pipe 14. The dust separation device 15 includes a cyclone 19, a bag filter 20 and a blower 21 arranged in series. The mercury-containing fluorescent powder 22 is separated and collected from the waste gas 13 by the cyclone 19, the exhaust gas from the cyclone 19 is treated by the bag filter 20, and the mercury-containing fluorescent powder 22 is further separated and removed. The mercury-containing fluorescent powder 22 obtained by separating and recovering from the waste gas 13 in this way is transported to the fluorescent powder processing device 23 in the next step.

The fluorescent powder processing device 23 includes a vacuum heating device 24
And a condenser 25. The mercury-containing fluorescent powder 22 is charged into a vacuum heating device 24 and is heated so that mercury is converted into mercury vapor 2.
6 and is sucked by the vacuum pump 27 and enters the condenser 25, where it is cooled to become metallic mercury and mercury 28 is recovered. On the other hand, mercury is separated and removed from the mercury-containing fluorescent powder 22 from the vacuum heating device 24, and the fluorescent powder 29 is recovered. As the fluorescent powder 29 collected here, a powder of safe quality that does not actually contain mercury can be stably obtained. Then, the mercury 28 and the fluorescent powder 29 are reused.

Reference numeral 31 denotes a mercury collecting device which collects a small amount of mercury remaining in the exhaust gas 30 'sucked by the vacuum pump 27 from the condenser 25 by the activated carbon adsorption tower 32'. The mercury collection device 31 includes the dust separation device 15 described above.
The trace amount of mercury contained in the exhaust gas 30 after passing through the bag filter 20 is also collected by the activated carbon adsorption tower 32. As shown in FIG. 1, two series of activated carbon adsorption towers 32 and 32 'are provided as the mercury collector 31 as shown in FIG.
They may be aggregated into a series. In addition, as a method of removing mercury in the exhaust gas 30 and 30 ′, a method of attaching an oxidizing agent such as ferric chloride to activated carbon to oxidize and adsorb and remove mercury gas, or a method of previously passing an oxidizing agent Any method may be employed in which a divalent mercury compound is used, and in this state, the compound is adsorbed and removed by a chelate resin having a thiol group. In addition to the mercury removal method using these dry adsorption methods,
When metallic mercury is contained in 0 ', the mercury in exhaust gas 30, 30' is oxidized with an oxidizing agent and absorbed in a solution containing water-soluble sulfide as a wet oxidation absorption method of mercury. Then, a device is added for removing as a hardly soluble mercury sulfide precipitate in water.

The pickling device 18 comprises an acid pickling tank 33 and a waste acid treatment device 34, and receives the crushed glass particles 17 from the waste fluorescent tube crushing device 1 and dilutes the crushed glass particles 17 with dilute acid 41.
By pickling and removing a small amount of mercury remaining in the
The main purpose of the apparatus is to obtain a crushed glass particle piece that has been cleaned and to recover a glass cullet 35 that can be reused for recycled glass, lightweight aggregate, tile, furniture, or the like. . The crushed glass grain piece 17 has an upper limit of 0.005 mg /
l of mercury, for example 0.03-0.09 mg
/ L of dissolved mercury may remain. Thus, the amount of residual mercury eluted was stably reduced to 0.005 mg /
1 or less. Here, among the pickling conditions, the type of acid, the acid concentration, the temperature of the pickling solution and the pickling treatment time are important,
In order to make the pickling operation safe, it is preferable that the temperature of the pickling solution is normal. As the type of acid, hydrochloric acid, nitric acid or sulfuric acid is desirable from the viewpoint of ease of handling and waste acid treatment, and it is particularly desirable to use hydrochloric acid from the viewpoint of mercury removal effect, handling and wastewater treatment.
Further, as for the acid concentration and the treatment time, when the residual amount of mercury is about 0.03 to 0.09 mg / l in terms of elution amount, 95 mm
ass.% or more, and in the case of immersion pickling in a static bath at room temperature, 1.0% when hydrochloric acid is used.
Over 1.5N, more preferably 1.5N diluted hydrochloric acid
hr or more, and when the hydrochloric acid concentration is below this, the amount of residual mercury eluted is stably maintained at 0.005 mg /
1 or less. Also, when nitric acid or sulfuric acid is used, almost the same conditions as when hydrochloric acid is used are required.

Waste acid 3 discharged from pickling tank 33 after pickling
6 neutralizes with a predetermined waste acid treatment device 34, and treats the eluted mercury as insolubilized mercury 37 such as mercury sulfide, drains the neutralized water 38, and discards the insolubilized mercury 37.

[0043]

EXAMPLES The present invention will be further described with reference to examples. FIG.
~ 110 W by the processing flow of the waste fluorescent tube shown in FIG.
The straight waste fluorescent tube was treated with a crushing capacity of 6.9 t / 8 hr. The base portions at both ends of the waste fluorescent tube were removed, and compressed air of 0.5 to 10 atm was emitted from the injection nozzle into the glass tube in a pulsed manner to clean the inside of the glass tube. With respect to the crushed glass particles obtained by crushing the glass tube thus cleaned with a crusher, and the glass cullet after the crushed glass particles have been pickled, the amount of mercury adhering to each is determined by the concentration of the eluted mercury. It was measured. Table 1 shows the conditions of pickling of the crushed glass particles and the measurement results of the dissolved mercury concentration before and after pickling.

[0044]

[Table 1]

As can be seen from Table 1, the amount of residual mercury inside the glass tube exceeds 0.005 mg / l, which is the value based on the dissolved mercury concentration in the environmental standard, only by the pulsed emission of the compressed air in the treatment of the waste fluorescent tube. However, the amount of mercury remaining in the glass was stabilized at 0.001 mg / mer by the pickling under appropriate pickling conditions.
1 or less.

[0046]

The most significant feature of the waste fluorescent tube treatment technique according to the present invention is that a method for thoroughly removing mercury from a waste fluorescent tube uses a mercury-containing fluorescent substance inside a glass tube whose both end sections are open. After the primary cleaning by blowing off by the injection of the compressed gas, the glass tube is crushed into pieces, and then
As a next cleaning step, a step of removing trace amounts of residual mercury by pickling it with a dilute acid is incorporated. Therefore, according to the present invention, in the treatment of the waste fluorescent tube, when reusing the crushed glass particles of the waste fluorescent tube,
When the amount of mercury remaining in the crushed glass particles is measured by the method specified in the environmental standard, stably lower it to the environmental standard value of 0.005 mg / l or less. Can be. Moreover, the obtained glass cullet can be reduced to a particle size advantageous for reuse. On the other hand, as for the mercury-containing fluorescent powder separated in the treatment step of the present invention, it is possible to obtain a safe powder that does not substantially contain residual mercury, and at the same time, to obtain a high-purity metallic mercury obtained by condensing mercury vapor. Collected. As described above, according to the present invention, it is possible to efficiently treat a large amount of waste fluorescent tubes while maintaining the above-mentioned advantages, and to reuse collected mercury, fluorescent powder, and metals such as aluminum. A processing method and a processing apparatus for a fluorescent tube can be provided, and an industrially useful effect is obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a processing flow of a waste fluorescent tube for explaining an embodiment of the present invention.

FIG. 2 is a partial detailed view in FIG. 1 and is a detailed view mainly showing a waste fluorescent tube crushing apparatus.

FIG. 3 is a partial detailed view of FIG. 1 and is a detailed view mainly showing a dust separation device and the like.

FIG. 4 is a partial detailed view in FIG. 1, and is a detailed view focusing on an pickling apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Waste fluorescent tube crusher 2 Waste fluorescent tube 3 Carry-in device 4 Sealable container (closed container) 5 Open burner 6 Cutting machine 4 Inside, 5, 6, compressed gas injection nozzle 7 and crusher 8 are provided. 7 Injection nozzle 8 Crusher 9 Compressed gas 10 Cap part 11 Glass tube 11 'Clean glass tube 12 Mercury-containing fluorescent powder 13 Waste gas 14 Suction gas pipe 15 Dust separator 16 Opening / closing valve 17 Crushed glass particles 18 Pickling glass Apparatus 19 Cyclone 20 Bag filter 21 Blower 22 Mercury-containing fluorescent powder 23 Fluorescent powder processing device 24 Vacuum heating device 25 Condenser 26 Mercury vapor 27 Vacuum pump 28 Mercury 29 Fluorescent powder 30, 30 'Exhaust gas 31 Mercury collecting device 32, 32 '' Activated carbon adsorption tower 33 Pickling tank 34 Waste acid treatment equipment 35 Glass cullet 36 Waste acid 37 Insolubilized mercury 38 Neutralization Risui 39 aluminum recovered 40 gaseous mercury 41 dilute acid 90 compressed gas generator

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tatsuo Kato 3-1, Bentencho, Tsurumi-ku, Yokohama-shi, Kanagawa Prefecture Inside Nuke Environment Co., Ltd. (72) Inventor Masahiro Muroya 3-1-1 Bentencho, Tsurumi-ku, Yokohama-shi, Kanagawa Prefecture Inside NKK Environment Co., Ltd. (72) Inventor Sazo Nakamura 3-1, Bentencho, Tsurumi-ku, Yokohama-shi, Kanagawa Prefecture F-term in NKK Environment Co., Ltd. AB03 AB10 BA02 CA04 CA12 CA22 CA40 CA50 CB12 CB13 CB34 CB45 CC12 4K001 AA14 BA24 CA01 CA02 DA14 DB03 DB04 DB05 EA02 EA08 GA08 GB09

Claims (9)

[Claims] 1. A method for treating a waste fluorescent tube, comprising the following steps (a) and (b). (A) The caps at both ends of the linear waste fluorescent tube are removed in a sealable container, and compressed gas is directed from one end to the other end of the glass tube portion of the obtained waste fluorescent tube. By ejecting, the gaseous mercury in the waste fluorescent tube and the fluorescent substance and mercury inside the glass tube portion are blown out and discharged into the sealable container, and the atmosphere inside the sealable container is sucked, Next, a step of separating and removing the gaseous mercury, the fluorescent substance, and mercury mixed in the fluorescent substance contained in the sucked waste gas. (B) The glass tube portion treated in the step (a) is crushed, the obtained crushed glass particle pieces are pickled, and mixed with the fluorescent substance remaining in the crushed glass particle pieces and the fluorescent substance. The process of separating and removing mercury. 2. Separating the gaseous mercury, the fluorescent substance, and mercury mixed in the fluorescent substance contained in the waste gas sucked from the inside of the sealable container in the step (a). The removing step is a step of treating the waste gas with a cyclone to collect the fluorescent substance containing mercury, and processing the collected fluorescent substance with a vacuum heating device and a mercury vapor condenser to obtain a fluorescent substance and mercury. And an exhaust gas containing mercury after the treatment with the cyclone, including a step of separating and removing the mercury from the exhaust gas by a dry adsorption method of mercury or a combination of the dry adsorption method and the wet oxidation absorption method. The method for treating a waste fluorescent tube according to claim 1, characterized in that: 3. When crushing the glass tube portion in the step (b), a glass particle piece of 15 mm or less is 95 ma.
preparing the crushed glass particles so as to have a particle size distribution occupying at least ss%, treating the crushed glass particles thus prepared in accordance with the step (b), and thus preparing and treating the crushed glass particles. 3. The method for treating a waste fluorescent tube according to claim 1, wherein the piece is used for recycled glass, lightweight aggregate, tile, or furniture. 4. The waste according to claim 1, wherein the acid used for pickling the crushed glass particles in the step (b) is hydrochloric acid, nitric acid or sulfuric acid. How to handle fluorescent tubes. 5. The method according to claim 1, wherein at least one hole penetrating the tube wall is formed in the waste fluorescent tube prior to removing the bases at both ends of the linear waste fluorescent tube in the step (a). The method for treating a waste fluorescent tube according to claim 1. 6. The waste fluorescent tube to be treated in the step (a) is ring-shaped, and prior to removing the base portion, two or more annular tubular waste fluorescent tubes are arranged in a circumferential direction. The method for treating a waste fluorescent tube according to any one of claims 1 to 5, wherein the base portion is removed. 7. A loading device for loading a waste fluorescent tube into a sealable container, a cutting machine for cutting and removing a base portion of the waste fluorescent tube in the sealable container, A gas injection nozzle for injecting a compressed gas for blowing and purifying mercury and a fluorescent substance remaining inside the cut glass tube portion of the waste fluorescent tube, and the glass tube whose inside is cleaned A waste fluorescent tube crushing device provided with a crusher for crushing a portion, and at the time of cutting and removing the base portion and at the time of injecting the compressed gas, the waste fluorescent tube is blown and discharged from inside the waste fluorescent tube into the sealable container. A dust separator for sucking the waste gas containing the mercury and the fluorescent substance, and separating and removing the mercury and the fluorescent substance from the sucked waste gas; and a fluorescent powder containing the mercury separated by the dust separator. Or A fluorescent powder processing device for separating and recovering each of mercury and fluorescent powder, and a mercury collector for collecting mercury from exhaust gas after the mercury and fluorescent powder have been removed by the dust separator. And an acid washing device for washing the crushed glass particle pieces crushed by the waste fluorescent tube crushing device with dilute acid, and separating and removing the fluorescent substance and mercury remaining in the crushed glass particle pieces. An apparatus for treating a waste fluorescent tube. 8. The waste fluorescent tube crushing apparatus further includes a gas burner for opening a through hole in a tube wall of the waste fluorescent tube in the sealable container before removing a base portion of the waste fluorescent tube. The processing apparatus for a waste fluorescent tube according to claim 7, further comprising: 9. The waste fluorescent tube according to claim 7, wherein the pickling apparatus for the crushed glass particle pieces is a pickling apparatus using diluted hydrochloric acid, diluted nitric acid, or diluted sulfuric acid. Processing equipment.