JPS599879B2 - radioactive waste incinerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an incinerator suitable for incinerating solid or liquid combustible radioactive waste to reduce its volume by incinerating it into ash.

An object of the present invention is to provide a long-life incinerator that has a simple structure, has few breakdowns, is easy to handle and maintain, and can replace worn parts without fear of corrosion or leakage of radioactivity.

According to the invention, this purpose is achieved by providing a solid cylindrical furnace interior lined with a refractory material, which consists of a large-diameter inner chamber surrounded by a vertical furnace wall and a narrow-diameter inner chamber below the large-diameter inner chamber. The two inner chambers are connected by an inclined furnace wall, and the large diameter inner chamber is equipped with a waste input opening, a combustion gas outlet, and a first air introduction pipe that opens tangentially. A swingable bottom cover is provided at the ash discharge opening at the lower end, and a second air introduction pipe is installed opening toward the bottom cover, and the entire furnace can be divided into multiple pieces vertically. This is achieved by an incinerator characterized in that it does not have a grate inside the furnace.

A more detailed configuration of the present invention will be explained below based on FIG. 1 showing one specific example.

The incinerator 1 according to the present invention has a rigid cylindrical shape and is composed of a large-diameter inner chamber 2 surrounded by a vertical slope furnace wall and a narrow-diameter inner chamber 3 below the vertical furnace wall. They are connected by a wall 4 and the entire furnace is lined with refractory material.

The solid radioactive waste is usually packed into a plastic bag and then introduced into the incinerator through the waste input opening 6 by the input device 5 installed on the upper side of the incinerator 1. Natural incineration occurs in the lower part of the furnace, mainly below the inclined furnace wall.

The combustion gas generated in this case is exhausted through a combustion gas exhaust T provided at the upper part of the large-diameter inner chamber 2, and is purified through a combustion gas pipe 8 lined with a refractory material (not shown). It is sent to a device where the soot and dust are removed, mixed with room temperature air, cooled, and discharged into the atmosphere from a chimney by a blower.

If the radioactive waste is combustible liquid waste, it is continuously injected into the incinerator by an injection pump via an injection device 9, which has a double structure, for example, and is installed on the upper lid of the incinerator.

The injection device 9 is removably attached to the furnace to protect it from scale build-up or melting.

The opening after removing the injection device 9 is closed to prevent leakage of radioactivity.

Similarly, the monitoring window 1 installed on the top cover of the furnace is in an air-cooled state.
The combustion and ashing process of waste is monitored through 0.

On the other hand, a swingable bottom cover 11 is attached to the ash discharge opening at the lower end of the narrow inner chamber 3.

When the bottom cover 11 pivots downward, the bottom cover 11 opens the entire cross section of the ash discharge opening, and as a result, the ash is removed by an ash removal device 14 consisting of an intermediate holding chamber 12 and a glove box 13 for temporarily holding the ash. and falls through the coarse grid 15 into the storage container 16.

Then, a first air introduction pipe 1 is installed on the lower furnace wall of the large-diameter inner chamber 2.
7 is installed with an opening in the tangential direction, and a part of the air necessary for combustion of radioactive waste in the furnace is supplied.

In this case, since the introduction pipe 17 is opened tangentially to the inner chamber 2, the introduced air flows along the inner wall of the furnace, and the air is mixed uniformly.

Further, a second air introduction pipe 18 is installed in the furnace wall of the small diameter inner chamber 3 and is opened in the radial direction toward the bottom cover 11 as shown in the figure.

This cools the bottom lid 11 and prevents the bottom lid 11 from being blocked or stuck by ash.

In order to mix the air uniformly, it is preferable that the second air introduction pipe 18 is also opened tangentially to the small diameter inner chamber 3 and in the opposite direction to the first air introduction pipe 17.

An auxiliary air supply pipe 19 is installed above the large-diameter inner chamber 2 and is used as a cooling air supply port when the temperature inside the furnace becomes too high, or when the combustion air is insufficient. Sometimes used as an auxiliary combustion air supply port.

The amount of introduced air can be adjusted using valves 17a, 18a, 19a provided on each introduction pipe 17, 1B and auxiliary air supply pipe 19.
done by.

Furthermore, since the incinerator according to the present invention can be divided into a plurality of parts vertically, for example, the furnace can be divided into three parts 20, 21, and 22 each having a flange part as shown in the figure. If the lower end of the intermediate portion 21 attached to the furnace 24 protrudes below the pedestal 24, the worn portions of the upper portion 20 and lower portion 22 of the furnace can be removed for repair.

As described above, in the present invention, since the first air introduction pipe of the large diameter inner chamber is opened in the tangential direction, mixing with air can be uniform and complete combustion can be achieved. The second air introduction pipe installed in the inner chamber is installed with an opening toward the swingable bottom cover installed in the ash discharge opening at the lower end of the small diameter inner chamber, so it can be used completely even without a grate. It can be incinerated and also prevents the bottom cover from clogging with ash.

In addition, since the entire furnace can be divided into multiple parts vertically, for example, the worn parts on the upper and lower sides can be easily removed from the furnace body for repair, and this incinerator has many advantages. This incinerator can be used as an incinerator for radioactive waste generated in Japan, and is an extremely useful incinerator industrially.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a longitudinal section of an embodiment of an incinerator according to the present invention. 1: Incinerator, 2: Large-diameter inner chamber, 3: Narrow-diameter inner chamber, 4: Inclined furnace wall, 5: Solid waste input device, 6: Waste input opening, 7: Combustion gas outlet, 8: Combustion gas pipe, 9: Liquid waste injection device, 10: Monitoring window, 11: Bottom cover, 12: Intermediate holding chamber, 13: Glove box, 14: Ash removal device,
15: coarse grid, 16: storage container, 17: first air introduction pipe, 18: second air introduction pipe, 19: auxiliary air supply pipe,
17a, 18a, 19a: Throttle valve.

Claims (1)

[Claims] 1. The inside of the furnace is a solid cylindrical furnace lined with personnel reinforcement, and consists of a large-diameter inner chamber surrounded by a vertical furnace wall and a narrow-diameter inner chamber below the vertical furnace wall, and both inner chambers have an inclined furnace wall. A waste input opening, a combustion gas exhaust opening and a first air introduction pipe opening in a tangential direction are installed in the large diameter inner chamber;
A swingable bottom cover is provided at the ash discharge opening at the lower end of the narrow inner chamber, and a second air introduction pipe is installed opening toward the bottom cover, and the entire furnace can be moved up and down. A radioactive waste incinerator characterized by being able to be divided into multiple parts and having no grate inside the furnace.