CN102338651A

CN102338651A - Reactor core liquid level measuring method for medical isotope production reactor

Info

Publication number: CN102338651A
Application number: CN 201010230082
Authority: CN
Inventors: 吴英华
Original assignee: Nuclear Power Institute of China
Current assignee: Nuclear Power Institute of China
Priority date: 2010-07-19
Filing date: 2010-07-19
Publication date: 2012-02-01

Abstract

The invention belongs to a reactor core liquid level measuring method for a nuclear reactor and particularly relates to a reactor core liquid level measuring method for a medical isotope production reactor. In the method disclosed by the invention, a plurality of small holes are formed on the same horizontal plane of the lower part of a liquid level measuring tube; then the liquid level measuring tube is arranged in a restraint tank; and the reactor core liquid level of the medical isotope production reactor is measured by a gas differential pressure method. In the method, gas is taken from a gas cavity at the upper part of the restraint tank, is pressurized by a gas entraining pump and is supplied to the liquid level measuring tube; solution in the liquid level measuring tube is pressurized; the solution flows out of the measuring tube from the small holes at the bottom of the liquid level measuring tube; and a gas pressure difference of a gas pressure in the liquid level measuring tube and a gas pressure in the gas cavity at the upper part of the restraint tank is measured by a gas differential pressure gauge, so that the reactor core liquid level is given.

Description

Medical-isotope production heap core level measuring method

Technical field

The invention belongs to a kind of nuclear reactor level measuring method, be specifically related to the level measuring method of medical-isotope production heap.

Background technology

Medical-isotope production heap belongs to a kind of " homogeneous solution-type reactor " type nuclear reactor, owing to adopt the uranium salt WS to make fuel, fission fragment bombardment water makes hydrone be decomposed into hydrogen and oxygen.Hydrogen or oxygen gas accumulates to a certain degree back formation air pocket in solution, from solution, rising escapes into air cavity.The heap container of medical-isotope production heap sealing is placed in the heap pond, and is very high to the insulation request in heap container and pond, must monitor the liquid level in the heap container.

Medical-isotope production heap level gauging generally adopts measuring tube; If measuring tube is placed in the heap container; Solution in the measuring tube receives the irradiation of persistent erection, and the uranium in the solution can be fissioned, its fission fragment bombardment water; Make hydrone be decomposed into hydrogen or oxygen gas, the accumulation of hydrogen or oxygen gas in measuring tube is unfavorable to the safety of medical-isotope production heap; If measuring tube is placed on outside the heap container, the thin fracture easily of measuring tube is unfavorable to the isolation in heap container and pond.

Core level to nuclear reactor is measured, and existing probe-type and two kinds of measuring methods of ultrasonic type because two kinds of measuring methods have following defective, all are not suitable for the level gauging of medical-isotope production heap.

The probe-type measuring method: owing to there being great amount of bubbles effusion liquid level to cause level fluctuation in the reactor core solution, in addition because solution thickness relatively has drop or solid adhesion on the probe, thereby the measurement meeting provides the liquid level glitch owing to the fluctuation of liquid level.

Ultrasonic wave measuring method: because hyperacoustic orientation, measurement needs the content gauge area bigger, and the liquid level signal of obtaining also can distortion.

Summary of the invention

The objective of the invention is to: a kind of core level measuring method that is applicable to medical-isotope production heap is provided.

Technical scheme of the present invention is following:

A kind of medical-isotope production heap core level measuring method, step is following:

Step 1: on the same surface level in level gauging pipe bottom, open some apertures;

Step 2: the level gauging pipe that will have some apertures is installed in the heap container;

Step 3: air cavity is got gas from heap container top, after adding the air pump pressurization, to level gauging pipe air feed, the solution in the level gauging pipe is pressurizeed;

Step 4: the gas differential pressure with in the gas differential pressure instrumentation amount level gauging pipe and heap container top air cavity provides core level.

Its supplementary features are:

Pressure to solution pressurization in the level gauging pipe in the said step 3 is 0.035～0.050MPa.

Effect of the present invention is: compare with existing measuring method, method of the present invention has been avoided the problem of measuring-signal distortion.Even this method is not owing to there is solution to have a spot of hydrogen can be along with the solution of gas from aperture is gone to measuring tube outside that flows basically in the level gauging pipe, and do not have the accumulation of hydrogen yet, guaranteed the safety that medical-isotope production is piled; Level gauging pipe bottom aperture can be realized the damping of level fluctuation, the solution of gas outside aperture is gone to measuring tube, has increased mixing of solution, helps the heat transfer of cooling tube.

Description of drawings

Fig. 1 is the level gauging synoptic diagram of measuring method of the present invention.

Among the figure: 1. fuel solution; 2. heap container; 3. air cavity; 4. add air pump; 5. level gauging pipe; 6. level gauging pipe bottom aperture; 7. gas differential pressure meter

Embodiment

Method of the present invention is that the level gauging pipe that radially has some apertures on the same surface level in bottom is installed in the heap container, adopts the gas differential pressure method to measure the core level of medical-isotope production heap.Concrete measuring method is following:

Step 3: air cavity is got gas from heap container top, through adding air pump pressurization back to level gauging pipe air feed, to the 0.035～0.050MPa that pressurizes of the solution in the level gauging pipe;

With 200kW medical-isotope production heap is example, and the level gauging signal is as shown in Figure 1:

The high about 30cm of liquid level is piled in the production of 200kW medical-isotope, adds the lift 35cm water column of air pump 4,0.5～5 liter/minute of flow.

On the same surface level in level gauging pipe bottom, open some apertures, the level gauging pipe 5 that has some apertures is installed in the heap container 2; The bottom is that fuel solution 1, top are air cavity 3 in heap container 2; Get gas from the top air cavity 3 of heap container 2; To level gauging pipe 5 air feed, to the pressurization of the solution in the level gauging pipe 5 0.035～0.050MPa, solution flows out liquid level measuring tube 5 from the bottom aperture 6 of level gauging pipe 5 after adding air pump 4 pressurizations; Make level gauging pipe 5 bottom apertures with the whole gassies in top, and have the solution of little of gas outside aperture is gone to level gauging pipe 5.With in the gas differential pressure meter 7 measuring liquid level measuring tubes 5 with the gas differential pressure of heap container 2 top air cavitys 3, can provide liquid level of solution.

Claims

1. the core level measuring method is piled in a medical-isotope production, and step is following:

2. according to the described medical-isotope production heap of claim 1 core level measuring method, it is characterized in that: the pressure to solution pressurization in the level gauging pipe in the said step 3 is 0.035～0.050MPa.