CN101789276A - A method and system for heating surface pool water of a pool reactor - Google Patents

Abstract

The invention discloses a method and system for heating surface pool water in a pool reactor. The method includes taking surface water, pressurizing it, and heating it. After the surface water is taken and is pressurized, impurity filtration, water quality purification, monitoring and sampling are performed, and the surface water is heated and then injected. Surface pool water. The system that implements the heating method includes a circulation pump (1) and a heating device (5). The system also includes a mechanical filter (2), an ion exchanger (3), a resin trap (4), and a monitoring sampling device; the circulation pump (1), mechanical filter (2), ion exchanger (3), resin trap (4), monitoring sampling device, and heating device (5) are connected in sequence through pipelines. The invention provides a method and system for heating surface pool water in a pool reactor that can filter impurities, purify water quality, monitor online, and adjust power.

Description

A method and system for heating surface pool water of a pool reactor

technical field

The invention relates to the technical field of nuclear reactor engineering, in particular to a method and system for heating surface pool water of a pool reactor.

Background technique

In a pool reactor, the core is immersed in the reactor pool. Due to the heating of the core, the highly radioactive water in the lower part of the reactor pool reaches the surface of the pool water through convection, resulting in a higher radioactive dose in the reactor hall. For this problem, the general processing method is to cover the cover plate on the pool water. With the development trend of advanced research reactors, it not only protects the operating environment, but also prevents the highly radioactive pool water from reaching the surface of the reactor pool, reduces the dose in the hall, and limits the exposure dose of operators. The more advanced technology in the prior art is to use the reactor The surface water of the pool is subjected to circulating heating treatment, so that the temperature of the surface water is higher than that of the lower part of the pool with higher radioactivity, and then the density of the surface water is lower than that of the water below. During the operation of the reactor, the water with higher radioactivity in the lower part cannot reach the surface of the pool water through convection, thus playing a shielding role.

At present, the HANARO research reactor in Daejeon, South Korea adopts this advanced technology. This technology has been operating in the HANARO reactor in Daejeon, South Korea for many years. The power of the HANARO research reactor is 30MW, the depth of the pool is 12.2m, the diameter of the pool is 4m, and the distance between the center of the active area and the surface of the pool water is 9.4m. It is designed that 90% of the coolant flow passes through the core, and the remaining 10% of the coolant bypasses into the pool and is sucked back to the core by the suction of the main pump, and part of it reaches the surface of the pool through natural convection, which increases the radioactivity on the surface of the pool. Therefore, a hot water layer circulation system is set up to form a hot water layer with a thickness of 1.6m and a temperature difference of 10°C on the surface of the pool water. However, there are deficiencies in the hot water layer formed by the technology used by the HANARO reactor. First, the technology lacks filtration, purification, and water quality monitoring of the hot water layer. Second, its heating power is constant and cannot be adjusted.

Contents of the invention

The invention overcomes the deficiencies of the prior art, and provides a method and system for heating surface pool water of a pool reactor capable of filtering impurities, purifying water quality, on-line monitoring, and adjusting power.

In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

A method for heating the surface pool water of a pool reactor, comprising the steps of supercharging and heating the surface water.

The system used in this method includes a circulating pump and a heating device. The key point is that the system also includes a mechanical filter, an ion exchanger, a resin trap, and a monitoring sampling device; the circulating pump, a mechanical filter, an ion exchanger, and a resin trap The detector, monitoring sampling device, and heating device are connected in sequence through pipelines.

Compared with the prior art, the beneficial effects of the present invention are: the present invention prevents radioactive leakage by setting mechanical filters, ion exchangers, resin traps, monitoring and sampling devices, and through steps such as impurity filtration and water purification. It plays a shielding role, ensuring that the radioactive dose in the reactor hall is maintained at a low level, and at the same time, online monitoring ensures that the water quality index of the surface pool meets the water quality requirements of the reactor.

Description of drawings

Figure 1 Schematic diagram of the system structure

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment the present invention is described in further detail:

The system includes circulation pump 1, mechanical filter 2, ion exchanger 3, resin trap 4, monitoring sampling device, heating device 5; circulation pump 1, mechanical filter 2, ion exchanger 3, resin trap 4 , the monitoring sampling device, and the heating device 5 are sequentially connected through pipelines. The monitoring sampling device includes an online conductivity meter 6 and a sampling box 7 . The circulation pump 1 provides power for the present invention, and the flow rate and head of the pump can be determined according to specific requirements and equipment structure. The mechanical filter 2 filters the insoluble suspended impurity particles in the water, and the ion exchanger 3 purifies the water quality, removes ionic state corrosion products, harmful impurities and fission products in the pool water, and also has the ability to filter solid suspended matter. The purpose of the resin trap 4 is to prevent the broken resin flowing out with water from the ion exchange column from entering the pool. The online conductance 6 is mainly used to monitor the water quality index, and the sampling box 7 is to facilitate sampling at any time. The purpose of the heating device 5 is to heat the purified return water on the surface and establish a hot water shielding layer. The heating power of the heating device 5 depends on the heat dissipation of the pool water, the heat preservation of the system and other factors, which can be adjusted as required.

The heating method using this system includes surface water intake and pressurization, heating, impurity filtration, water quality purification, monitoring and sampling after surface water intake and pressurization, and injecting surface pool water after heating and heating. The method can establish the density difference between the upper and lower pool water, preventing the highly radioactive pool water with lower temperature from reaching the surface of the pool water through convection. At the same time, the water quality of the surface pool is guaranteed to meet the requirements through filtration, purification and online monitoring.

This embodiment adopts a circulating pump 1, a mechanical filter 2, two ion exchangers 3 that can be connected in series or combined, a resin trap 4, and is composed of an online conductivity meter 6 and a sampling box 7 Monitoring sampling device, electric heating device 5 (120KW, 4 groups in total, each group 30KW), the system flow control is 15m ³ /h. The reactor was put into operation 24 hours before the reactor was opened. The system relies on the circulating pump to absorb water from the lower part of the reactor pool water surface, and obtains power after passing through the circulating pump. The mixed ion exchanger 3 in series is used for water purification, and the purified pool water meets the water quality index of the reactor pool, and the broken resin is filtered through the resin trap 4, and the temperature is raised by the heating device 5 installed on the pipeline, and the heated high-temperature water It reaches the top of the pool water surface, forming a cycle. Water quality monitoring can be carried out through the online conductivity meter 6 at any time during the circulation process, and sampling monitoring can also be carried out in the sampling box 7 at any time. Stop running after 24 hours after shutdown. Through this invention, the average temperature difference between the hot water shielding layer and the water in the lower pool can be established to be about 5 degrees, and the average thickness of the hot water shielding layer is 3 meters, so that the highly radioactive water in the lower part of the pool cannot reach the surface of the pool during the operation of the stack, which plays a very good role. shielding effect.

The invention can greatly reduce the operating dose rate of the reactor hall, which can be reduced by an order of magnitude. It can well meet the requirements of reactor operation.

Claims (3)

1. the heating means of a surface pool water of pool type reactor comprise the surface water taking supercharging, and heating is characterized in that, carry out contaminant filter, purification of water quality, monitoring sampling after the described surface water taking supercharging, through injecting top layer Chi Shui behind the heat temperature raising.

2. the employed system of the heating means of a kind of surface pool water of pool type reactor according to claim 1, comprise ebullator (1), heating arrangement (5), it is characterized in that system also comprises mechanical filter (2), ion-exchanger (3), resin catcher (4), monitoring sampler; Ebullator (1), mechanical filter (2), ion-exchanger (3), resin catcher (4), monitoring sampler, heating arrangement (5) connect successively by pipeline.

3. system according to claim 2 is characterized in that, described monitoring sampler comprises online conductivity meter (6) and sampling cabinet (7).

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