DE1214333B - Pool core reactor - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

G21c

German class: 21g-21/20

Number: 1214 333

File number: C 34265 VIII c / 21 g

Filing date: October 30, 1964

Opening day: April 14, 1966

The invention relates to a swimming pool core reactor with one of vertical, in the lower part an open top water-filled Chamber arranged and cooled by an upwardly directed water circuit fuel elements formed core, with facilities to water through at least one in a low Distance above the upper level of the core arranged opening of the chamber and discharge it to cool and partially decontaminate, and with facilities to keep most of this water at lower end of the core and the other part in the upper area of the chamber above the lateral Reintroduce openings.

As is known, one of the main advantages of this type of reactor is the easy accessibility of the active one Core area. Various procedural measures can be taken through the body of water lying above the core undertake, such as the use of fuel elements and the insertion of specimens to be irradiated. However, that is one of these Reactors performance to be achieved because of the heating of the water in the vicinity of the core and the resulting boiling phenomena.

In order to achieve a higher output without the occurrence of these boiling phenomena, the water must be used pressurize in the neighborhood of the core. So one uses one that surrounds the core sealed chamber, but loses the main advantage of the pool core reactors mentioned above, because the core is no longer accessible.

The invention aims to increase the possibilities for increasing the performance of a swimming pool core reactor while maintaining easy access to the core.

According to the invention, this is achieved in the aforementioned swimming pool core reactor in that at least some of the fuel elements carry a deflector at their upper end to deflect the There escaping water to direct the side openings.

The following is with reference to Figs a particular embodiment of the invention described without thereby limiting it.

F i g. Figure 1 shows an elevation of a pool core reactor according to the invention;

F i g. Figure 2 shows a top view of the same pool core reactor;

F i g. 3 shows further details of the structure of a fuel element.

The pool core reactor shown in FIG. 1

Applicant:

Commissariat a l'Energie Atomique, Paris

Representative:

Dr. H. U. May, patent attorney,

Munich 2, Ottostr. la

Named as inventor:

Paul Ageron, Grenoble, Isere;

Guy Denielou,

Aix-en-Provence, Bouches-du-Rhone

(France)

Claimed priority:

France of October 30, 1963 (952 336)

tor consists of a concrete container 1, which is filled with water up to a height 2, and the core 3 contains. This consists of fuel elements arranged next to one another, each of which has one Arrangement 4 comprised of parallel plates of fissile material. Each arrangement rests on one metallic holder 5 which terminates in a foot 6 which is arranged on a base of the container 1 Grate 7 is supported.

A cylindrically shaped metal chamber 8 separates the zone adjacent to the core from the rest of the Swimming pool. This chamber 8 is equipped with a safety dam device 8 a for the introduction of experiments close to the core. During the operation of the reactor, the chamber 8 prevents the Mixing of the water in the vicinity of the core with the water of the rest of the swimming pool. It rests on the bottom of the container 1 and is essentially halfway up by an annular, on the walls of the container 1 attached transverse plate 25 held. This plate serves at the same time in addition, the ring-shaped water mass located outside the chamber in two layers one above the other Zones to divide, the lower zone being a deactivation chamber 24.

The chamber 8 has in its lower part on the inside a horizontal stage (9, 10 in Fig. 1), which in

609 558/334

Claims (1)

3 4 the middle carries a grate 11. This with further order an ascent of the activated water to Details in Fig. 2 stage shown comprises surface 2 of the swimming pool, where the with four metal plates 9, 10, 12 and 13, which were used for the experiments on the reactor 8 are firmly connected and to which the find, to avoid, is in the upper part of the Grate 11 is attached. 5 swimming pool one level from top to bottom The dimensions of the grids 7 and 11 correspond to the provided water flow. This water will each other; the grate 7 carries the fuel elements, the cooling circuit of the core after the deactivation and the grate 11 holds it in a vertical position. approximately chamber 24 removed. It can be partial or However, a certain number of holes has to be completely cleaned before it gets to the top of the Do not rust open fuel elements. This freely ge ίο chamber 8 is introduced through a line 28, Allow holes in the vicinity of the core in a with deflection devices, not shown various experimental arrangements, such as a distribution system 29 provided with a measuring loop, opens. The water fen, which on the supports 5 · of the fuel elements returns to the cooling water circuit 23 at the level of the appropriate carriers are attached. Suction openings 22, 23 back. In Fig. 1 at 15 and 16 two of these measuring loops are 15 In Fig. 3 is the structure with further details to see fen. In which neither of fuel elements of a fuel element is shown. In this figure holes still occupied by test arrangements, the reference symbols have the same meaning as elements corresponding to the carriers 5 are shown in FIG. 1. It can be seen that the fuel element with sets, which at its upper part is a square, which is provided with a transverse plate 30, which by means of a Plate 17 covering holes in the grate 11. 2 ° structure 31 allowing cooling water to pass through That is solidified by the not shown Wärmeaus-. This plate on which the water is perpendicular Cooling water discharged from exchangers is pushed from top to bottom by pumps and is used to About two in the middle area of the carrier 5 of the soft of the element under the pressure of the through Lines 18 and 19 opening into fuel elements, lines 18 and 19 of introduced cooling water initiated again. This water occurs to prevent ascending 25. the sense through the fuel assemblies 4 to the natural convection currents in the upper through and then spreads in the pool. Decreasing the pool area is one In order to force the cooling water, the whole active manifold 32 is provided, which there is a hot water mass to traverse before it is maintained in the upper layer and so the ascent of At the height of the core distributed in the pool, 30 activated water can reach the pool surface one should prevent a (not shown) around the core. surrounding the fuel elements, but their The advantages of the described swimming pool upper ends leaving the box with straight core reactors mainly result from the Arrange side walls. You can also use any system for increasing the pressure in the reactor core, the one Fuel element with a power increase that is open on both sides and without the occurrence of boiling entire length of the arrangement of the panels from appearances and at the same time easy access Fissile material surrounding sleeve with straight to the core area through the remaining open upper Side walls provided. Under these conditions part of the swimming pool allows. This If the mean pressure in the core is equal to the sum of the pool core reactor is therefore to the Durchdes hydrostatic pressure corresponding to the height 40 execution of experiments particularly suitable and offers of the swimming pool above the core and also great adaptability to different that of the pressure loss in the fuel elements. Uses. This increase in pressure in the core enables cooling after an increase in output of the reactor while maintaining the reactor in a very simple manner without the advantages of the usual swimming pool core 45 required for an emergency power source reactors. will. The circulation-maintaining pumps To the direct ascent of the by the Corezone pen are provided with flywheels, which during coming water of the swimming pool for the first seconds after stopping the reaction To prevent area 2, the upper part of the burner or a reduction in output is sufficient Provide fabric elements with deflection devices 20, ensure 5 ° pump output. When the water which the water at an angle of 45 ° with respect to the pressure of the core circuit essentially the deflect the vertical. That reaches out of the core from pool pressure, one opens on emerging water (in FIG. 1 by the arrows 21 the lines 18 and 19 upstream of the core indicates) is of .einem in the middle area of the outside of the chamber 8 arranged flap valve cylindrical chamber 8 arranged system of 55 and establishes the connection between core and Intake openings 22 and 23 added. These pools. The cooling then takes place Intake openings are available with the deactivation by natural convection. This is supported by the chamber 24 in connection, which is improved from that of the height of the chamber 8. This device Container 1, the cylindrical chamber 8 and works even if the pumps fail,
60 contributing to keeping the chamber 8 vertical Ring plate 25 limited lower zone of the swimming claims: pelvis is formed. The through the suction 1. Swimming pool core reactor with one off gen 22 and 23 withdrawn from the swimming pool vertical, in the lower part of an open top Water lingers in the deactivation chamber 24 arranged and through the water-filled chamber and an upwardly directed water circuit is then created through lines 26 and 27 from 65 Derived from the reactor to the outside and formed in front of the cooled fuel elements with the core Recirculating various treatments under- facilities to water through at least one threw. ; . at a small distance above the upper one Level of the core arranged lateral opening of the chamber to drain and to cool and partially to decontaminate, and with facilities to keep most of this water on lower end of the core and the other part 5 in the upper area of the chamber above the to re-introduce lateral openings, characterized in that at least some of the fuel elements (4) carry a deflector (20) at their upper end in order to to direct the exiting water towards the lateral openings (22). 2. Swimming pool core reactor according to claim 1, characterized in that the chamber (8) inside a body of water divided into two compartments by a transverse partition (25) is arranged, wherein the lower compartment (24) is one discharged from the chamber (8) Water absorbing deactivation chamber forms. 3. Swimming pool core reactor according to claim 2, characterized in that the devices to return the main part of the water to the end of the core at least one through the deactivation chamber (24) include line (18) with a flap valve is provided to allow water from the chamber (24) to enter the line (18) when the pressures prevailing on both sides become the same. 4. Swimming pool core reactor according to claim 1, 2 or 3, characterized in that the devices for returning the main part of the water to the lower end of the core (2) comprise a line (18) which opens into a manifold through which the carrier (5) are guided, the the fuel elements (11) extend and placed on one at the bottom of the swimming pool Grate (7) rest and are provided with a transverse plate (30) on which the water is one downward pressure that counteracts the buoyancy of the elements. Considered publications:
"Directory of Nuclear Reactors", Vol. III, 1960, p. 12. 1 sheet of drawings 609 558/334 4. 66 © Bundesdruckerei Berlin