DE1132260B - Gamma irradiation system and radiation body for such a system - Google Patents

Description

GERMAN

PATENT OFFICE

D 33542 Vnic / 21g

REGISTRATION DATE: JUNE 11, 1960

NOTICE
THE REGISTRATION
AND ISSUE OF
EDITORIAL: JUNE 28, 1962

The invention relates to a gamma irradiation system, consisting of an irradiation chamber with solid artificial radioactive isotopes, a reactor core, in which these isotopes are continuously activated, and a closed cycle for the Isotope that connects the irradiation chamber to the reactor core.

The invention is based on the object of a simple, continuous or intermittent construction and operation to create working gamma irradiation system with a possibility to adjust each desired radiation intensity and each radiation spectrum.

In research reactors it is known to activate material samples in any aggregate state to be brought into or removed from a reactor by irradiation. Serve for activation continuously operating gamma irradiation systems, mostly with a liquid between the reactor and the irradiation chamber is circulated, which a neutron radiation in the reactor absorbs and then serves as an activating gamma source in the irradiation chamber. For such Systems are different liquids, such as. B. water, liquid metals or chemical compounds used. However, this usually results in great operational difficulties because the liquids often lead to severe corrosion. In addition, these must be kept under overpressure and also tend to decompose under the influence of radiation.

To avoid these disadvantages and difficulties in the operation of irradiation chambers in A connection with liquid gamma sources has already been proposed, instead of the one used as a radiation source, to use solid substances circulated between the reactor and the irradiation chamber, the z. B. come in the form of an endless belt, which is activated in the reactor and then releases the absorbed energy to the material to be irradiated as it passes through the chamber. In the however, practical implementations of this solid-state process are also occurring significant difficulties. One of these problems is e.g. B. the question of material, as an endless belt Very few fabrics are suitable for such a purpose, because the tape is constantly deformed and the high radiation exposure, which is known to cause embrittlement in many materials leads, must not lose its elasticity. Besides, it's just a lot with this run difficult possible the actual radiant substance gamma irradiation system

and radiation body

for such a plant

Applicant:

German Babcock & Wilcox Steam Boiler -

Works Aktien-Gesellschaft,

Oberhausen (RhId.)

Dipl.-Phys. Horst Borgwaldt,

Neureut via Karlsruhe,
Arno Müller and Dipl.-Phys. Roland Schneider,

Oberhausen (RhId.),
have been named as inventors

to protect with a non-radiant or very little radiant, abrasion-resistant layer. Another disadvantage This endless band consists in the fact that it always has the same composition over its entire length must have, so that a certain energy of the emitted radiation is assigned to each strip material and a change is only possible by replacing the entire belt.

In order to avoid these disadvantages, in one with solid artificially radioactive isotopes in one Circuit of the type mentioned continuously or intermittently operating gamma irradiation system according to the invention in the reactor core activated isotopes used, which in a manner known per se from consist of a large number of radiation bodies. These can, for example, have a spherical shape and circulate in a closed circuit between the reactor and the irradiation chamber.

The use of such irradiated balls or pearls, which to achieve a certain Irradiation dose strung on strings is already known in medicine, in irradiation systems however, of the type described above, the use of such balls has not yet been proposed been.

Due to the use of this spherical shape known from medical radiation technology or otherwise designed solid radiation body in

209 617/32 »

Such irradiation systems are compared to those with circulated liquids or with endless circulating Gamma radiation chambers working with bands achieved significant improvements. Next to the avoidance of the disadvantages of such systems already mentioned, the possibility is also created the transport of the radiation body for the implementation of a closed circuit by mechanical means Conveyors can be carried out continuously or intermittently along guide channels allow. A vertically arranged screw conveyor is used for this purpose, which enables certain Move the radiation body a fixed distance at intervals. By voting the aktorkem, can be added. This makes it possible to use the transfer channel 4 of radiation bodies to keep free and to transfer the freshly activated radiation body very quickly from the reactor to the radiation chamber.

The device according to the invention can also be used advantageously in research reactors. In this case, the channel 2 is expediently led laterally past the reactor core.

In order to dissipate the heat generated in the radiation bodies during the radiation in the reactor, a coolant is also fed through channel 2. The normal reactor coolant can often do this be used. In this case the

The irradiation with the body 15 ^to transport "and discharge of the coolant through two materials Öff-

The port speed of this screw can be any desired radiation intensity and any desired Generate radiation spectrum in the irradiation chamber.

According to a further embodiment of the invention, a radiation body through the guide channels is guided coolant flow provided in order to dissipate the heat generated in the radiation body.

It is also particularly advantageous to use the radiation body used according to the invention to provide an abrasion-resistant, tight cover, which consists of steel, zirconium or aluminum and prevent is intended to ensure that activated substances are deposited in the conveying lines and the screw conveyor. Such coatings for spherical or pearl-shaped radiation bodies are also known per se.

As a filler for the radiation body are suitable e.g. indium, sodium, manganese, lanthanum or gallium in pure form or as a chemical compound or alloy with other materials.

The irradiation system according to the invention is simplified in the drawing in one embodiment shown.

The spherical radiation bodies 1 run in a channel 2 through the reactor core 3 and from there in a transfer channel 4 to the irradiation chamber S. With a return mechanism, for example is shown as a vertically arranged screw conveyor 6, which is in a cylindrical, shaft provided with a longitudinal groove? is running, the radiation bodies are then via the supply line 8 returned to the reactor 3 again. The groove in the shaft 7 prevents the radiation bodies Roll back on the screw conveyor 6.

As a return mechanism can of course any other construction can also be used. The system can also be detachable by additional Lock in the lines of the radiation body, for example by a lock 9 under the Renungen 10 and 11 in channel 2.

Claims (5)

PATENT CLAIMS: 1. Gamma irradiation system, consisting of an irradiation chamber with solid artificial radioactive isotopes, a reactor core in which these isotopes are continuously activated, and a closed circuit for the isotopes, which connects the irradiation chamber with the reactor core, characterized in that in the reactor core (3) activated isotopes consist of a large number of radiation bodies (1) in a manner known per se (figure). 2. Gamma irradiation system according to claim 1, characterized in that the transport of the Irradiation body (1) for carrying out a closed circuit it through mechanical conveying devices takes place continuously or intermittently along guide channels (2, 4, 7, 8) (Figure). 3. Gamma irradiation system according to claims 1 and 2, characterized in that a coolant flow guided through the guide channels of the radiation body is provided. 4. irradiation body for a gamma irradiation system according to claims 1 to 3, characterized characterized in that this is enclosed by an abrasion-resistant, tight cover. 5. Irradiation body according to claim 4, characterized in that it is made of indium, Manganese, sodium, lanthanum or gallium in its pure form, a chemical compound or a Alloy of these substances is made. Considered publications: German Auslegeschriften No. 1023155, 1076837;
U.S. Patents Nos. 2,743,226, 2,751,505, 2781309. For this purpose, 1 sheet of drawings © 209 617/329 6.