JPS6041320B2 - Processing method for waste ion exchange resin in heavy water-moderated nuclear reactors - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a waste ion exchange treatment method used in a heavy water-moderated nuclear reactor. The aim is to sterilize the resin and make it convenient for storage.

In heavy water-moderated nuclear reactors, ion exchange resins are used to purify heavy water by removing metals that have been lacquered in the heavy water, but the ability of ion exchange resins to remove metals is affected by contact with heavy water. As a result, in heavy water purification equipment of nuclear reactors, waste ion exchange resin (hereinafter abbreviated as waste resin) whose metal removal ability has declined is replaced with new ion exchange resin (hereinafter abbreviated as new resin). It has been replaced and the waste resin has been disposed of. By the way, when disposing of waste resin, conventionally, the heavy water held by the waste resin is replaced with light water to make the waste resin lighter water, and then this is discharged outside the system along with the resin transfer water, and the waste resin is left as it is as it is. A method of storing it in a tank is adopted.

However, this method not only has a problem in that the tritium contained in the waste resin and resin transfer water after lightening is released outside the system, but also because the waste resin is stored in its original form, which makes it bulky. I also don't like it because it makes it tense. The present invention proposes a new method for treating waste resin that eliminates all the drawbacks of the conventional methods described above by incinerating the waste resin, and this method is used in heavy water purification equipment for heavy water-moderated nuclear reactors. Add light water to the waste ionized fat,
The tritium-containing heavy water held by the resin is replaced with light water to make the resin lighter, and the degraded heavy water is recovered. After separating this degraded heavy water into tritium-containing heavy water and light water using heavy water purification equipment, the tritium-containing heavy water is purified as described above. The resin is circulated through the equipment and the lightened resin is incinerated to produce gaseous waste and solid waste, which is molded into any shape and stored. This is sent to a condenser to condense the water vapor in the gaseous waste, and the resulting condensed water is used as part of the light water for converting waste resin into water and/or as part of the waste resin transfer water. It consists of passing non-condensable gas discharged from the condenser through a filter and then releasing it outside the system.

Hereinafter, the method of the present invention will be explained in more detail with reference to the attached drawings. In the heavy water purification equipment 1 of a nuclear reactor, light water is poured into waste resin used for purification of heavy water, and the heavy water held by the waste resin is removed. Water-lightening of pseudo-resin is carried out by replacing it with light water.

At this time, degraded heavy water is obtained, which is a mixture of heavy water and light water.
As in the conventional method, this degraded heavy water is sent to the heavy water purification facility 5 via line 7, and after being separated into tritium-containing heavy water and light water by means such as fractional distillation, the tritium-containing heavy water is sent via line 8 to the heavy water purification facility 1. The light water can be discharged out of the system through line 9. Heavy water purification equipment 1
The waste resin that has been reduced to light water is sent to the incineration facility 2 through a line 10 together with resin transfer water (light water).

During this time, new resin is supplied to the heavy water purification equipment 1 from the line 16, and it goes without saying that the new resin is converted into heavy water by replacing the light water held by the new resin with heavy water. Incidentally, when converting new resin into heavy water, degraded heavy water is produced as in the case where waste resin is converted into light water, but this degraded heavy water can be treated in exactly the same manner as described above. The waste resin supplied to the incineration facility 2 is incinerated here to generate gaseous waste and solid waste.

The solid waste consists of incineration residue such as ash, which is sent to the solidification facility 3 via the line 11, where it is formed into an arbitrary shape and then stored in a storage facility or the like. on the other hand,
The gaseous waste taken out from the competition equipment 2 to the line 12 is led to the condenser 4, where the water vapor containing tritium is condensed, and then returned to the heavy water purification equipment 1 via the line 13, where the waste resin is It is reused as water for lightweighting and/or resin transfer water. Non-condensable gases that are not condensed in the condenser 4 are sent to the filter 6 through a line 14, where impurities are separated, and then discharged to the outside of the system through a line 15.
As described above, according to the method of the present invention, it is possible to reduce the number of customers by incinerating the waste resin, so that the capacity of the tank for storing the waste resin can be significantly reduced.

In addition, the moisture in the waste resin and the resin transfer water are evaporated when the pseudo-resin is accepted and then recovered into the system by condensation of the gaseous waste, so the tritium entrained in these is collected in the system. The danger of release to the outside can be avoided.

[Brief explanation of drawings]

The drawing is a block diagram showing one embodiment of the invention. 1; Tarumi purification equipment, 2; Incineration equipment, 3: Solidification equipment, 4
; Condenser; 5; Heavy water purification equipment; 6; Filter.

Claims (1)

[Claims] 1 Light water is added to the waste ion exchange resin used in the heavy water purification equipment of a heavy water-moderated nuclear reactor, and the tritium-containing heavy water held in the resin is replaced with light water, making the resin lighter and recovering the degraded heavy water. After heavy water is separated into tritium-containing heavy water and light water using heavy water purification equipment, the tritium-containing heavy water is circulated through the heavy water purification equipment, and the light water resin is incinerated to produce gaseous waste and solid waste. The waste is molded into any shape and stored, while the gaseous waste is sent to a condenser to condense the water vapor in the gaseous waste, and the resulting condensed water is poured into waste ion exchange resin. The non-condensable gas discharged from the condenser is passed through a filter and then released outside the system. A method for treating waste ion exchange resin in a heavy water-moderated nuclear reactor.