JPH05290805A - Mercury enclosed lamp - Google Patents

Abstract

PURPOSE:To provide a mercury enclosed lamp capable of easily recovering most of mercury remaining inside a bulb of the lamp to be broken such as a fluorescent lamp which has finished its lifetime before a cleaning or roasting process is carried out. CONSTITUTION:In a lamp where an electric discharge electrode 5 and mercury are enclosed inside a glass bulb 1, a mercury adsorbing body 11, which is enclosed inside a glass container 13 or covered with glass and is exposed to produce amalgam when the glass container 13 is broken due to expiration of the lamp lifetime, is contained inside the bulb 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mercury-encapsulated lamp capable of easily recovering mercury, which is a problem when a lamp having mercury filled in a bulb such as a fluorescent lamp having a long life is discarded.

[0002]

2. Description of the Related Art For example, in a fluorescent lamp, mercury for efficiently converting electric energy into ultraviolet light in a glass bulb and Ar, Ne, Kr, He for facilitating discharge starting are used.
A mixed gas discharge lamp filled with a rare gas such as mercury. Mercury is a liquid at room temperature. Except some lamps, the liquid is filled directly or in a capsule or in a pelletized state. ing.

By the way, when the fluorescent lamp is turned on, mercury produces HgO due to the presence of oxygen originating from the impure gas remaining in the bulb and the impure gas generated from barium carbonate which is an undecomposed substance of barium oxide as the emitter material. , Adsorbed by the phosphor applied to the inner wall surface of the bulb. Since the adsorbed HgO does not contribute to discharge, it is necessary to fill the bulb with mercury in an amount corresponding to the rated life of the lamp.

For example, the document HIROTA. T and others "F
luorecent Lampsusing am
"ensure dispenser" J. Light
& Vis, Env1 (1977) 1, the unit internal surface area of the fluorescent lamp and the mercury consumption per unit time are 6.
It is given as 5 × 10 EXP-7 mg / cm ² · Hr.

Therefore, for example, if a straight tube 40 W type fluorescent lamp has a bulb inner diameter of about 26 mm and a length of about 1200 mm, it consumes about 7 mg of mercury during lighting for 10,000 hours.

If the amount of mercury in the bulb is insufficient, the starting characteristic of the lamp will deteriorate.

By the way, since it is considered that the consumption rate of mercury largely depends on the concentration of the impure gas remaining in the bulb and the lighting conditions, the mercury is usually enclosed in several times this amount in anticipation of these losses. .. In addition, even if a fixed amount of mercury is filled, it is necessary to allow for some variation such as a change in the amount due to the temperature difference between individual bulbs and a loss attached to the filling device. It contains about 10 times more mercury. in this way,
In the bulb of a fluorescent lamp that has reached the end of its life, more mercury than the amount consumed during the lighting life, which is generally determined by the life of the electrode, remains.

Fluorescent lamps in which mercury is enclosed in a glass bulb are divided into glass, phosphor, mercury, metal, etc. after the end of their life and become unnecessary products, from the viewpoint of reusing resources and preventing environmental pollution. The process is strict.
As a treatment method, the lamp is crushed to an appropriate size and divided into a glass part, an electrode part, a base part, etc., and these crushed pieces are washed away with water to remove the phosphors and mercury adhering to them, and the phosphors are removed from this waste liquid. Known methods include a cleaning method for recovering mercury and mercury, and a culturing method for cooling and recovering the mercury vapor that has been expelled by putting crushed pieces into a rotary furnace for heating.

According to these treatment methods, the valve is crushed into an indefinite shape from the beginning of the treatment, so that mercury and the like which are granularly rolled on the inner wall of the valve are purposely collected by the treatment device. Although it is difficult to leak mercury from these processing equipment, it is needless to say that it is preferable that the amount of mercury recovered is as small as possible, and there is a demand for a way to reduce the mercury recovery rate without leakage.

It is also known that the efficiency of a fluorescent lamp changes depending on the vapor pressure of mercury depending on the temperature, and the light output of the lamp becomes maximum when the mercury vapor pressure is about 6 mTorr. In a lamp used for illumination at a high temperature, there is an amalgam of mercury as a means for obtaining such mercury vapor pressure. Finally, most of the mercury in the glass bulb is adsorbed by the amalgam-forming substance in the lamp in which the mercury is amalgamated, and there is an advantage that the diffusion of mercury can be prevented by recovering the amalgam-forming substance when the lamp is discarded.

However, when a lamp containing an amalgam-forming substance is used in homes, offices, etc., it is not in a high temperature atmosphere, and on the contrary, the efficiency is lowered, which is not preferable, and most of the fluorescent lamps currently produced are ordinary. It is a lamp filled with liquid mercury.

[0012]

The problem to be solved by the present invention is that most of the mercury remaining in the bulb of a lamp to be discarded, such as a fluorescent lamp that has reached the end of its life, must be cleaned or burned. It is an object of the present invention to provide a mercury-filled lamp that can be easily recovered before being carried out.

[0013]

A mercury-sealed lamp of the present invention is a lamp in which a discharge electrode and mercury are sealed in a bulb. The bulb is hermetically sealed or glass-coated in a glass container, and the glass is sealed during the life of the lamp. It is characterized in that a mercury adsorbent that is destroyed and exposed to form an amalgam is arranged.

[0014]

[Function] A mercury adsorbent (amalgam-forming substance) that shields the mercury remaining in the glass bulb of a fluorescent lamp that has become unnecessary when it has reached the end of its life.
It is adsorbed by exposing the glass to amalgamate most of the mercury in the glass bulb to facilitate its recovery and reduce the amount of mercury recovery in the final treatment by the washing method and the cultivation method.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows one end of a straight tube type fluorescent lamp of the first embodiment. In the figure, 1 is a glass bulb having a phosphor layer 2 formed on the inner surface, and 3 is sealed at the end of the bulb 1. Flare stems, 4A and 4B are lead wires crushed and sealed in the stem 3, 5 is a coiled filament carrying an emitter which constitutes a discharge electrode connected between the lead wires 4A and 4B, and 6 is a base. Lead wire 4 extending from stem 3
It has pins 7A and 7B connected to A and 4B, respectively. Further, 11 is a mercury adsorbent in which a metal plate held by a support 12 planted in the stem 3 is plated with indium, 13 is a spherical glass container that hermetically surrounds the mercury adsorbent 11, and 14 is this glass. It is a metal wire wound around the outer circumference of the ball 13.

Further, as usual, about 20 mg of mercury and about 3 torr of argon gas are enclosed in the bulb 1.

When the fluorescent lamp having such a structure is lit up and reaches the end of its life, a high frequency wave is applied to the metal wire 14 provided on the outer circumference of the glass bulb 13 of the stem 3 of the lamp to electromagnetically heat the metal wire. Heat 14 When the metal wire 14 is heated, the glass container 13 is locally heated, that is, the glass container 13 is locally distorted and the glass container 13 is cracked, and the mercury adsorbent 11 plated with indium is placed in the discharge space. Exposed, and the adsorption of mercury in the bulb 1 begins. Indium easily forms an amalgam with mercury, and if the amount of indium and the surface area are properly selected, almost all the mercury remaining in the bulb 1 will be adsorbed by indium.

After that, the glass bulb 1 is broken and the mercury adsorbent 11 (amalgam) having a high mercury concentration by adsorbing mercury is replaced with a glass part having a low mercury concentration, an electrode part, a base part, etc. Collect separately. Then, mercury is separately collected from the mercury adsorbent 11 (amalgam) having a high mercury concentration, and the members having a low mercury concentration are treated by the conventional cleaning method and culture method, respectively. to recover.

FIG. 2 shows a second embodiment of the present invention,
The same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. The second embodiment has a button stem 3A.
The mercury adsorbent 11 made of an indium plate having a heater 15 and a glass coating 13 around the lower support 12A that airtightly penetrates substantially the center of the stem and an upper support 12B that extends from the lead 4A. Are connected in series. In the figure, 4C indicates the lead 4A and the stem 3A.
External pins 8 extending outward are terminals provided on the outer surface of the stem 3A and are electrically connected to the lower support 12A.

When the fluorescent lamp having such a structure is turned on and the life is reached, the heater 15 generates heat by passing a current between the external pin 4C and the terminal 8 of the lamp. Due to the heat generated by the heater 15, the indium plate, which is the mercury adsorbent 11 near the heater 15, thermally expands and the glass coating 13 is distorted and destroyed. Then, the indium plate is exposed in the glass bulb 1, so that the mercury in the glass bulb 1 is adsorbed as in the first embodiment.
After that, the processing and operational effects after destroying the lamp are the same as those in the first embodiment, so the description thereof is omitted.

The present invention is not limited to the above embodiment. For example, the lamp is not limited to the hot-cathode type fluorescent lamp, but may be a cold-cathode type fluorescent lamp, and the lamp can be applied to a lamp in which mercury is enclosed such as an ultraviolet lamp or a high-pressure mercury lamp. Further, although the above describes the mercury recovery of the lamp which has been lit up and has reached the end of its life, it is needless to say that it is of course applicable to the disposal of a defective lamp that has occurred in the manufacturing process of the lamp that constitutes the present invention or a lamp that is discarded such as a lamp recovered by regular replacement. The present invention can be applied.

Further, the amalgam forming the mercury adsorbent is not limited to indium, but may be one of bismuth, tin, lead, zinc, or an alloy containing them, and the location of the amalgam is not limited to the location of the embodiment. In other words, as long as it has an amount and surface area capable of adsorbing the mercury remaining in the glass bulb.

[0023]

As described above in detail, according to the present invention, the glass is shielded by the glass while the lamp is lit and in use, and when the lamp is discarded after it has reached the end of its life, the glass is destroyed and the mercury adsorbent ( The amalgam forming substance is exposed to adsorb the residual mercury in the glass bulb. If this mercury adsorbent with a high concentration of mercury is collected separately, most of the mercury in the bulb can be taken out. ，
After that, the portion with a low concentration of mercury may be separately collected for each member such as the glass portion, the metal portion, the plastic portion, the mercury, and the phosphor by a cleaning method or a cultivation method.

Therefore, most of the mercury is amalgamated and recovered with a simple structure, and only the member having a low concentration of mercury is treated in the secondary treatment stage. Can be reduced, which can contribute to the improvement of work safety and the environment.

[Brief description of drawings]

FIG. 1 is a partially sectional front view showing a main part of a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional front view showing a main part of a second embodiment of the present invention.

[Explanation of symbols]

 1 Glass bulb 5 Discharge electrode 11 Mercury adsorbent (amalgam forming substance) 13 Glass container, glass coating

Claims (3)

[Claims] 1. A lamp with a discharge electrode and mercury sealed in a bulb, wherein a mercury adsorbent that forms an amalgam at the end of the lamp life is placed in the bulb. .. 2. The mercury-filled lamp according to claim 1, wherein the mercury adsorbent is sealed in a glass container and the container is broken at the life of the lamp to form an amalgam. 3. The mercury-filled lamp according to claim 1, wherein the mercury adsorbent is glass-coated and the coating is broken during the life of the lamp to form an amalgam.