KR910003578B1 - Filter of radio-active waste matter - Google Patents

Abstract

The apparatus having a centrifugal dust-collector and a ceramic filter, performs secondary combustion of unburnt inflammable elements in hot exhaust gas which is generated from incineration of nuclear solid wastes, and trapping of the particulate. The apparatus comprises the process piping being coated with fire-proof cement (1) for passing hot exhaust gas (2); burner (3) for reburning; centrifugal dust collector (4) with lower rotary valve (5) and ash tray (6); porous ceramic filter (7) including filter body (8) penetrated with the compressed-air inlet pipe.

Description

Combined post-combustion high temperature filter for radioactive waste incineration process

1 is a cross-sectional structure diagram of a post-combustion high temperature filtration apparatus of the present invention.

The present invention relates to a centrifugal dust type ceramic filter for hot gas for trapping the secondary combustion of unburned combustible components and solids in the hot exhaust gas generated during incineration of radioactive solid waste.

The hot exhaust gases generated during incineration of waste contaminated with radioactivity, microorganisms or hazardous chemicals contain suspended solid particles which should not be released into the atmosphere, and in order to prevent the exhaust gas treatment equipment from being contaminated or blocked by solids. Exhaust gases should be treated immediately after discharge from the incinerator.

However, it is difficult to come up with high dust removal efficiency, long time operation and easy regeneration filtration device under the temperature of about 700-1000 ℃ of gas discharged from the incinerator, and treatment by cooling the hot exhaust gas by heat exchange or air dilution method In this case, there is a problem that the apparatus becomes complicated and excessive load is applied to the exhaust gas treatment system.

In addition, a large amount of unburned combustible components in the exhaust gas due to incomplete combustion during waste incineration requires a secondary combustion chamber in order to completely burn unburned dust.

In order to solve such a problem, the present invention is a device for completely burning the unburnt in the high-temperature exhaust gas generated during incineration of radioactive waste and at the same time as a device for filtering and removing solid matter at high temperature in the pipeline. Secondary combustion of unburned fine powder by re-ignition increases the complete combustion rate, eliminating the risk of fire in the exhaust gas treatment system by unburned powder, and directly connects centrifugal dust collector and ceramic filter to increase dust removal efficiency, install refractory inside the process, and use it at high temperature The use of a ceramic filter makes it possible to operate for a long time and to be easily regenerated without the risk of radioactive cover of the driver by attaching an automatic backwash device.

In addition, by using a centrifugal dust collector and a ceramic filter as a post-combustion chamber for the complete combustion of high-temperature exhaust gas, heat loss is reduced, the exhaust gas treating device is simplified, and the load of the apparatus is reduced.

Hereinafter, the gist of the present invention will be described in detail with reference to the incineration process implementation and structural drawings.

This device is composed of centrifugal dust collector with unburned secondary combustion and vibration damping function and porous ceramic filter which can be used at high temperature, and it is constructed of refractory brick or refractory cement (1) inside each unit, To prevent damage to the material due to thermal shocks such as expansion or contraction of the material, and the hot exhaust gas (2) generated in the incinerator flows to the post-combustion and high temperature filter by the exhaust fan installed at the end of the incineration process. It is ignited by the burner 3 installed in the inside and flows into the centrifugal dust collector 4 while secondary combustion.

The hot exhaust gas 2 introduced in the tangential direction of the centrifugal dust collector 4 is dropped below the centrifugal dust collector 4 by tangential and radial flows, and finally, the airtight rotary valve attached to the bottom of the centrifugal dust collector 4 ( 5) The hot exhaust gas 2, which is removed by the recollection box 6 and first purified by the centrifugal dust collector 4, is introduced into the porous ceramic filter 7 installed on the centrifugal dust collector 4.

The ceramic filter material 8 is a long cylinder type that can be used and regenerated at a high temperature. The hot exhaust gas 2 escapes from the outside of the cylinder to the inside of the ceramic filter material 8 and collides with the ceramic filter material 8, Blocking and diffusion remove solids.

The hot exhaust gas (2) passing through the ceramic filter (7) is processed in a secondary dust collector or discharged to the atmosphere through a stack, and a differential pressure gauge is installed on the upper and lower flow sides of the ceramic filter (7). When the pressure loss through the material 8 is greater than or equal to the prescribed value, the pressure of the ceramic filter material 8 is pulsated by supplying the compressed air of water pressure through the reverse compressed air inlet 9 attached to the upper portion of the ceramic filter 7. The ceramic filter material 8 is regenerated by removing the solids attached to the outer wall.

The upper part of the ceramic filter material (8) has a flange type, and the main component of the material is silicon oxide, which is easily broken by vibration. Prevents damage due to contact and maintains airtightness.

The upper part of the ceramic filter is preferably manufactured to be easily disassembled and assembled so that the filter material can be easily replaced when the filter material reaches the end of its useful life or the material is damaged.

If the flow rate of the exhaust gas is greater than that of one ceramic filter material, it is impossible to install multiple ceramic filter materials within the diameter of the centrifugal dust collector outlet. Therefore, the inlet to the ceramic filter material is inclined upward from the centrifugal dust collector outlet pipe. After widening the diameter, it is carried out by attaching as many porous ceramic filter materials as the desired aeration amount.

The present invention as described above has a shielding function to prevent the damage of the material due to thermal shock, such as expansion or contraction of the metal material due to the high temperature and at the same time can expect the effect of preventing the worker's coating by radiation. There is a double effect as a post-combustion and filter to remove suspended solid particles.

Claims (3)

The high-temperature exhaust gas (2) generated during incineration of radioactive solid waste is condensed into a refractory cement (1) instead of a separate post-combustion chamber and connected in a process pipe equipped with a burner (3), which is connected to a centrifugal dust collector (4), Install the rotary valve (5) and the recollecting box (6) and the upper end forms a porous ceramic filter (7) and the ceramic filter material (8) through which the compressed air inlet (9) is cylindrically penetrated. A post-combustion high temperature filtration device for the radioactive waste incineration process, the outlet of which is connected with a stack. 2. The post-combustion for radioactive waste incineration process according to claim 1, wherein the centrifugal dust collector (4) and the outlet of the centrifugal dust collector (4) are directly used as the inlets of the porous ceramic filter (7) without separately installing the centrifugal dust collector (4) and the porous ceramic filter (7). And high temperature filtration equipment. The radioactive waste incineration process according to claim 1 or 2, wherein when using at least one ceramic filter material (8), the diameter of the outlet of the centrifugal dust collector (4) is expanded immediately at the outlet and used as an exhaust gas inlet to the ceramic filter (7). Combustion and high temperature filter.

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