阅读说明：本技术 基于特征参数分析的后处理厂应急状态分级确定方法 (Post-processing plant emergency state grading determination method based on characteristic parameter analysis ) 是由 王任泽 张建岗 杨亚鹏 冯宗洋 梁博宁 贾林胜 王宁 李国强 庄大杰 徐潇潇 于 2020-12-01 设计创作，主要内容包括：本发明涉及一种基于特征参数分析的后处理厂应急状态分级确定方法,所述方法包括如下步骤：步骤1、描述后处理厂的主要设施；步骤2、分析后处理厂主要设施的典型事故；步骤3、确定后处理厂主要设施的典型事故涉及的特征参数,对特征参数进行分析；步骤4、确定后处理厂应急状态分级。本发明提供的后处理厂应急状态分级确定方法将后处理厂内潜在的事故类型、严重程度与事故过程中的各种特征参数及其指示相联系,从而制定出与实际相符的应急行动水平。(The invention relates to a method for determining the emergency state of a post-processing plant based on characteristic parameter analysis in a grading manner, which comprises the following steps: step 1, describing main facilities of a post-treatment plant; step 2, analyzing typical accidents of main facilities of the post-processing plant; step 3, determining characteristic parameters related to typical accidents of main facilities of the post-processing plant, and analyzing the characteristic parameters; and 4, determining the emergency state classification of the post-treatment plant. The method for determining the emergency state of the post-processing plant in the grading manner provided by the invention relates the potential accident type and severity in the post-processing plant with various characteristic parameters and indications thereof in the accident process, thereby making an emergency action level which is consistent with the actual situation.)

1. A grading determination method for an emergency state of a post-processing plant based on characteristic parameter analysis is characterized by comprising the following steps:

step 1, describing main facilities of a post-treatment plant;

step 2, analyzing typical accidents of main facilities of the post-processing plant;

step 3, determining characteristic parameters related to typical accidents of main facilities of the post-processing plant, and analyzing the characteristic parameters;

and 4, determining the emergency state classification of the post-treatment plant.

2. The method according to claim 1, wherein the main facilities of the post-treatment plant include a spent fuel receiving and storing facility, a post-treatment process facility, and a high level waste liquid treatment facility.

3. A risk assessment method for an after-treatment plant according to claim 1, wherein the typical accident scenario of the spent fuel receiving and storing facility includes a spent fuel storage pool cooling system failure, an abnormal drop in water level.

4. A method for risk assessment in an after-treatment plant according to claim 1, wherein typical accidents of the after-treatment process facility include critical accidents, red oil explosion accidents, organic phase combustion accidents.

5. A risk assessment method in an after-treatment plant according to claim 1, wherein typical accident scenarios of the high level wastewater treatment facility include storage tank hydrogen explosion accident, storage tank leakage accident.

6. A method for risk assessment at a post-processing plant according to claim 4, wherein the characteristic parameters of the critical event include critical control quality or control concentration, ambient dose equivalent rate, gamma dose rate, radioactive aerosol concentration; the characteristic parameters of the organic phase fire accident comprise solvent leakage, aerosol, temperature, light intensity, gamma dose rate and radioactive aerosol concentration; the characteristic parameters of the red oil explosion accident comprise liquid level in the evaporator, temperature, pressure, density, sump liquid level, radioactive aerosol concentration and environment gamma dose rate.

7. A hazard assessment method for a post-processing plant according to claim 5, wherein the characteristic parameters of a hydrogen explosion accident of the storage tank include liquid level in the storage tank, temperature, pressure, density, hydrogen concentration, sump level, gamma dose rate, radioactive aerosol concentration; the characteristic parameters of the storage tank leakage accident comprise liquid level of a liquid level sump in the storage tank, gamma dose rate, radioactive aerosol concentration and environment gamma dose rate.

8. The method for risk assessment of an aftertreatment plant according to claim 3, wherein the characteristic parameters of the spent fuel storage pool cooling system failure include pool water temperature, gamma dose rate; the characteristic parameters of the abnormal reduction of the water level of the spent fuel storage pool comprise the liquid level of the pool, the temperature of the pool water and gamma dose rate.

9. The method for risk assessment of an aftertreatment plant according to claim 6, wherein the specific method for determining the emergency status rating of the aftertreatment plant in step 4 is as follows:

(1) when two parameters of critical control quality or control concentration exceed the normal process operation limit value, the risk of a potential critical accident is indicated, and emergency standby is carried out at the moment;

(2) when the equivalent rate of peripheral dose monitored by a critical accident alarm instrument and the gamma dose rate monitored by a fixed gamma monitor exceed a certain limit value for a certain time, entering a factory for emergency;

(3) when the gamma dose rate monitored by a fixed gamma monitor and the radioactive aerosol concentration monitored by an iCAM aerosol continuous measurement instrument exceed a certain limit value for a certain time, entering a field area for emergency;

(4) when the gamma dose rate monitored by the fixed gamma monitor and the radioactive aerosol concentration monitored by the iCAM aerosol continuous measurement instrument exceed a higher limit value for a certain time, the system enters an off-site emergency.

Technical Field

The invention belongs to the technical field of nuclear industry, and relates to a method for determining emergency states of a post-processing plant in a grading manner based on characteristic parameter analysis.

Background

The nuclear fuel circulation facility divides the emergency state into four levels according to the severity of the radiation consequences of possible events and accidents and the emergency response action to be taken, and the emergency state is emergency standby, factory emergency, field emergency and off-site emergency. Each emergency condition has its basic characteristics and corresponding qualitative or quantitative criteria.

The emergency state of the nuclear fuel circulation facility may include two stages (emergency standby, plant emergency), three stages (emergency standby, plant emergency, and site emergency), and even four stages (emergency standby, plant emergency, site emergency, and off-site emergency), depending on the type, characteristics, and the like of the nuclear fuel circulation facility. The level of emergency situations that can occur in a nuclear fuel recycling installation can therefore be determined analytically by the type of nuclear accident that has occurred and its installation consequences etc. For most nuclear fuel circulation facilities in China, off-site emergency is generally not considered, but facilities with higher potential risks may need to be implemented. It must be ensured that the established emergency grading system can cover all emergency situations that may occur in its facility.

For a nuclear fuel cycle plant, the classification criteria for the four contingencies are not entirely quantitative criteria, and even quantitative criteria, only the radiation consequences are generally taken into account. For possible emergency situations, a link to the radiation consequences needs to be established by the characteristic parameters.

So far, the characteristic parameters of typical accident scenarios of an after-treatment plant, and the connection of the typical accident scenarios to emergency situations are not all clear.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a method for determining the emergency state of the post-processing plant in a grading manner based on characteristic parameter analysis, so as to establish the relation between the typical accident situation of the post-processing plant and the emergency state and grasp the type and severity of the potential accident in the post-processing plant.

In order to achieve the above purposes, the invention adopts the technical scheme that:

the method for determining the emergency state of the post-processing plant based on the characteristic parameter analysis in a grading manner is provided, and comprises the following steps:

step 1, describing main facilities of a post-treatment plant;

step 2, analyzing typical accidents of main facilities of the post-processing plant;

step 3, determining characteristic parameters related to typical accidents of main facilities of the post-processing plant, and analyzing the characteristic parameters;

and 4, determining the emergency state classification of the post-treatment plant.

Further, the main facilities of the post-treatment plant comprise a spent fuel receiving and storing facility, a post-treatment process facility and a high-level radioactive liquid waste treatment facility.

Further, typical accident scenarios of the spent fuel receiving and storing facility include a spent fuel storage pool cooling system failure, and an abnormal drop in water level.

Further, typical accidents of the post-treatment process facility include critical accidents, red oil explosion accidents, organic phase combustion accidents.

Further, typical accident scenarios of the high-level radioactive liquid waste treatment facility include a storage tank hydrogen explosion accident and a storage tank leakage accident.

Further, the characteristic parameters of the critical accident include critical control quality or control concentration, peripheral dose equivalent rate, gamma dose rate, and radioactive aerosol concentration; the characteristic parameters of the organic phase fire accident comprise solvent leakage, aerosol, temperature, light intensity, gamma dose rate and radioactive aerosol concentration; the characteristic parameters of the red oil explosion accident comprise liquid level in the evaporator, temperature, pressure, density, sump liquid level, radioactive aerosol concentration and environment gamma dose rate.

Further, the characteristic parameters of the hydrogen explosion accident of the storage tank comprise liquid level, temperature, pressure, density, hydrogen concentration, sump liquid level, gamma dose rate and radioactive aerosol concentration in the storage tank; the characteristic parameters of the storage tank leakage accident comprise liquid level of a liquid level sump in the storage tank, gamma dose rate, radioactive aerosol concentration and environment gamma dose rate.

Further, the characteristic parameters of the faults of the spent fuel storage pool cooling system comprise pool water temperature and gamma dose rate; the characteristic parameters of the abnormal reduction of the water level of the spent fuel storage pool comprise the liquid level of the pool, the temperature of the pool water and gamma dose rate.

Further, the specific method for determining the emergency state classification of the post-processing plant in the step 4 is as follows:

(1) when two parameters of critical control quality or control concentration exceed the normal process operation limit value, the risk of a potential critical accident is indicated, and emergency standby is carried out at the moment;

(2) when the equivalent rate of peripheral dose monitored by a critical accident alarm instrument and the gamma dose rate monitored by a fixed gamma monitor exceed a certain limit value for a certain time, entering a factory for emergency;

(3) when the gamma dose rate monitored by a fixed gamma monitor and the radioactive aerosol concentration monitored by an iCAM aerosol continuous measurement instrument exceed a certain limit value for a certain time, entering a field area for emergency;

(4) when the gamma dose rate monitored by the fixed gamma monitor and the radioactive aerosol concentration monitored by the iCAM aerosol continuous measurement instrument exceed a higher limit value for a certain time, the system enters an off-site emergency.

The invention has the beneficial technical effects that: the method for determining the emergency state of the post-processing plant based on the characteristic parameter analysis quantifies the accident/event and the consequence thereof, can master the potential accident type and the severity degree in the post-processing plant through the process, and can work out the emergency action level which is consistent with the reality through being associated with various characteristic parameters and indications thereof in the accident process.

Drawings

FIG. 1 is a step diagram of a method for grading and determining an emergency state of an aftertreatment plant based on characteristic parameter analysis according to the present invention.

Detailed Description

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

As shown in fig. 1, the present invention provides a method for hierarchically determining an emergency state of an aftertreatment plant based on characteristic parameter analysis, the method comprising the steps of:

step 1, describing main facilities of a post-treatment plant; the main facilities of the post-treatment plant comprise a spent fuel receiving and storing facility, a post-treatment process facility and a high-level radioactive waste liquid treatment facility.

Step 2, analyzing typical accidents of main facilities of the post-processing plant; typical accident scenarios of the spent fuel receiving and storing facility include a spent fuel storage pool cooling system failure, and an abnormal drop in water level. Typical accidents of the post-treatment process facility include critical accidents, red oil explosion accidents, and organic phase combustion accidents. Typical accident situations of the high-level radioactive liquid waste treatment facility comprise a hydrogen explosion accident of a storage tank and a leakage accident of the storage tank.

And 3, determining characteristic parameters related to typical accidents of main facilities of the post-processing plant, and analyzing the characteristic parameters. The characteristic parameters of the emergency state grading corresponding to the typical accident are shown in the table 1.

TABLE 1

And 4, determining the emergency state classification of the post-treatment plant. Taking the case of dealing with the critical accident of the main process facility later, the specific determination method is as follows:

(1) when two parameters of critical control quality or control concentration exceed the normal process operation limit value, the risk of a potential critical accident is indicated, and emergency standby can be carried out at the moment;

(2) when the equivalent rate of peripheral dose monitored by a critical accident alarm instrument and the gamma dose rate monitored by a fixed gamma monitor exceed a certain limit value for a certain time, entering a factory for emergency;

(3) when the gamma dose rate monitored by a fixed gamma monitor and the radioactive aerosol concentration monitored by an iCAM aerosol continuous measurement instrument exceed a certain limit value for a certain time, entering a field area for emergency;

(4) when the gamma dose rate monitored by the fixed gamma monitor and the radioactive aerosol concentration monitored by the iCAM aerosol continuous measurement instrument exceed a higher limit value for a certain time, the system enters an off-site emergency.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include such modifications and variations. The foregoing examples or embodiments are merely illustrative of the present invention, which may be embodied in other specific forms or in other specific forms without departing from the spirit or essential characteristics thereof. The described embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. The scope of the invention should be indicated by the appended claims, and any changes that are equivalent to the intent and scope of the claims should be construed to be included therein.