JPH0124640Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the structure of the off-gas outlet of a glass melting furnace (melter) used in the vitrification process of high-level radioactive waste liquid.

Glass melting furnaces contain glass materials and high-level waste liquid and heat and melt them, but at this time high-level radioactive off-gas is generated. For this reason, this off-gas is taken out from the glass melting furnace by suction and introduced into an off-gas treatment facility for treatment.

However, the atmospheric temperature in the upper space of the glass melting furnace is 200 to 400°C during heating operation, but because the operation is a batch operation, during standby it reaches 800°C, which exceeds the softening point of glass (approximately 500°C). It is heated from front to back. For this reason, the dust containing glass particles in the furnace atmosphere softens and adheres to the inner circumferential surface of the off-gas nozzle at the off-gas outlet.
It solidifies by reaching a steady operating temperature of 300℃,
It is expected that if these actions are repeated, dust will accumulate and the off-gas nozzle will become clogged. Such a blockage situation must be avoided at all costs, since it will become impossible to treat the high level of off-gas in the glass melting furnace.

The present invention was developed in view of these circumstances, and by providing an off-gas nozzle with a tapered opening and a cooling device on its outer periphery at the off-gas outlet of a glass melting furnace, the off-gas nozzle is The purpose is to prevent the adhesion and adhesion of dust to prevent clogging of off-gas nozzles.

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows an example of the present invention, in which 1 represents a glass melting furnace, and the glass melting furnace 1 is connected to a second glass melting furnace.
As shown in the figure, it is composed of an outer wall 2 and a fireproof lens 3 provided on the inner surface thereof, a heating electrode 4 is provided on the outer periphery of the lower part, and an inlet 5 for glass material and high-level waste liquid is provided on the upper part. An outlet 7 for taking out the melting furnace 6 is provided at the bottom. Furthermore, an off-gas nozzle 8 is provided on the upper outer periphery of the glass melting furnace 1, and the off-gas nozzle 8 is connected via a dust scrubber 9 to a suction fan 10 provided at the rear.

The shape of the outlet of the glass melting furnace 1 of the off-gas nozzle 8 in the above is made to have a curved or linear tapered shape T as shown in FIG. A cooling coil 11 or a cooling jacket 12 as shown in FIG. 3 is provided, and the off-gas nozzle 8 is cooled by supplying water 13.

According to the above configuration, by forming the opening of the off-gas nozzle 8 into a tapered shape T, it is possible to prevent the off-gas from contracting, thereby smoothing the flow of the off-gas and reducing the adhesion of dust.

Furthermore, the off-gas nozzle 8 is provided with a cooling coil 1.
Since a cooling device such as 1 or a cooling jacket 12 is provided, the temperature of the off-gas nozzle 8 is set below the softening point of glass (approximately 500°C) (preferably at an annealing temperature of 350°C or below), thereby reducing glass particles. The contained dust becomes difficult to adhere to and is prevented from sticking, and the dust is guided to the dust scrubber 9 and removed by the suction force of the suction fan 10.

Note that the present invention is not limited to the above-mentioned embodiments, and various changes may be made without departing from the gist of the present invention.

As described above, according to the off-gas nozzle for the glass melting furnace of the present invention, by having the tapered opening, it is possible to prevent the off-gas from condensing and make it difficult for dust to adhere, and also to cool the glass melting furnace. By providing this device, it is possible to prevent dust from softening and solidifying, thereby achieving an excellent effect of eliminating the risk of clogging the off-gas nozzle and improving the safety of the device.

[Brief explanation of the drawing]

Figure 1 is an overall explanatory diagram of the device to which the present invention is applied;
FIG. 2 is an enlarged detailed view of the off-gas nozzle section in FIG. 1, and FIG. 3 is an explanatory diagram showing a different embodiment of the present invention from FIG. 2. 1 is a glass melting furnace, 8 is an off-gas nozzle, 11
12 is a cooling coil, 12 is a cooling jacket, and T is a tapered shape.

Claims (1)

[Scope of utility model registration request] An off-gas nozzle for a glass melting furnace, characterized in that a nozzle having a tapered opening is provided at the off-gas outlet of the glass melting furnace in a vitrification process of high-level waste liquid, and a cooling device is provided around the outer periphery of the nozzle.