DE2062933A1 - Cooling system for fluid-cooled nuclear reactors - Google Patents

Description

Patent attorneys

Dipl. Ing. G. Wallactt ο 1 ntn «,

Dipl. I-α. α Koeh / ^U & 970

Y ^{12 969J} * ^{H / r}

Dr. , .Yiaibach ^{12 969J} * · ^{H / r}

8 Εϊ: 'ί ·. "· -Ί'.; Βη2
Kaufingerstr. 8, Tel. 240278 2062933

1. British Nuclear Design * Construction Limited, Whetstone, Leicester, England, Great Britain

2. The English Electric Company

Bush House, Aldwych, LOEDON, WG2B 4QJ »'. Great Britain

Cooling system for fluid-cooled nuclear reactor

The invention relates to a cooling system for a mid-flow coolant Nuclear reactor with little or no capacity to absorb excess heat has a drop from an operating state with high external heat output.

Cooling systems are available for mid-flow cooled nuclear reactors proposed which a Waaser = intermediate cooling circuit for heat transfer from the reactor core coolant to another cooling circuit and from there to a heat sink such as the sea or the atmosphere. To the integrity of the reactor even in the event of a catastrophic failure To ensure the input power supply, emergency power generators of high capacity would have to be installed, which the performance required to maintain the necessary circulation of the coolant in the Zwiechenkühlkrelslauf and ensure the further cooling circuit for rapid heat dissipation from the reactor core coolant.

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The installation of such emergency energy supplies would be expensive and impractical; since the investment costs of such emergency energy supplies are closely related to to be able to stand, it was a great advantage » when the total energy needs of the noteaaergiiavea ^ supply fall below Emergency conditions are set at the feerafo.

The invention thus relates to & ± n cooling system for a fluid-cooled nuclear reactor with a water intermediate cooling circuit for heating from deia Re & ktoreore coolant to a world cooling circuit.

To solve the mentioned problem “d, h. ~ V @ rrlxäges? Ung of Gee.smtenergiebedas f3 of Kühlsysteras in Notsustand of the invention is provided according to that d T Kühlmittalkreis- = running with Ernest safety valve sum Äblas «j © n of fessar or Danspf & \ λ & the cooling circuit when the pressure in the Zwiachenkuhlkreislauf © in a given user path, as well as provided with a feed water supply device, by means of which the cooling circuit is provided under pressure to the board. for the security vaatil drained water "the drained Daupf is cycled"

Thus one karm at. the A-uablldiaii-g ^ according to the invention

or failure of the input air supply for the energy supply, the water cooling circuit, the water contained in it, due to the safety, to the load conitnöii "in" whereby 3.3 heat from the reactor coolant abiiarbiert. On Tues & 3e ¥ aise, the Not-Ene: rifieaggre | »iitan aufzubringend® power ^^ ² * ^diei Aufrechterhai processing of Wassasrumwriiaung in dam Zwischsnkühikreislauf proved - significantly verjfijag © r * be t>.?.

BATH ORIGINAL

.Λ 109827/1009

According to preferred embodiments of the invention it can be provided that the emergency feed water supply device is connected to the intermediate circuit at a point upstream of the heat exchanger assigned to the reactor core coolant, and that the safety valve is arranged downstream of this heat exchanger between the heat exchangers and the connection point with the emergency feed water supply device is, and that ± n the intermediate cooling circuit upstream of the connection of the emergency feedwater supply device but downstream of the safety valve, a check valve is provided.

Thus, the emergency water supply device is in use Essentially all of the intercooling circuit-J on supplied feed water through the reactor core coolant assigned heat exchanger flow and thus withdraw heat from the R & aktorcore coolant *

The following is an embodiment of the invention described with reference to the drawing} this shows a schematic partial representation of a cooling system according to the invention.

A water intermediate cooling circuit designated as a whole by 1 has a heat exchanger with a pre-heater 2 and an intermediate cooler, which mixes the heat transfer between the central cooling circuit and the core coolant in the gas-cooled nuclear reactor located at the sea - ^ cilt. The Vorküh.lei · 2 and d "" r intercooler 3 are arranged in a wall of the h JReaktcrdruckgefäQes and a (not shown) Diroktkroislauf gas turbine associated with "velche cooling gas tus deri reactor core as a turbine

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BATH ORIGINAL

working fluids used

Also in the Zwlschenkühlkx® islauf is © in another Heat exchanger 5 provided "which the heat transfer from Intermediate cooling circuit to another cooling circuit

produces, which is designated as a whole with 6 and sea water used as a heat sink and provided with a circulating pump (not shown) »B © ± an im Inland reactor facility kömat © this additional one Cooling circuit for example © inen or several cooling towers © |) ssur delivery of the warning © to the atmosphere instead of to the sea exhibit. To compensate for -aormal © small loss © Intermediate cooling is a supply of pre-treated a (i.e. demineralized) water over © im only in one Direction permeable or check valve 7 is provided. The cooling circuit also includes a circulating pump 8, at the pressure or discharge outlet © in the non-return valve 9 is provided.

Upstream of the further heat exchanger 5 is provided for a purpose described below © in safety valve 10, to which a (not shown) ventilation vent to the atmosphere is assigned; further are a * © Not "Speisewass®rzufuhrvorrichtung with an emergency feedwater tank 11, an emergency feed water pump 12 and a check valve 13, in series with each other, provided in the intermediate cooling circuit upstream of the precooler. 2

The circulation pump stops during normal operation of the cooling system 8 the wa.sarairculation in the intermediate cooling circuit 1 upright, and accordingly the circulation becomes

D ORIGINAL

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in the cooling circuit 6 of the heat sink through the corresponding Maintain circulation pump (not shown). In the event of a decrease or failure of the energy supply, however, energy would normally have to be used for the pumps from (not emergency units such as batteries or diesel-powered generators can be supplied. at such a drop or failure of the normal input power supply would affect the reactor from the example switched back to full reactor output power, and im In view of the thermal inertia of the reactor core (not shown) and the inability of the gas turbine to generate excessive Absorbing heat would be quick in such a case Cooling of the reactor core coolant is of particular importance.

In the system according to the invention, the circulation pumps in the intermediate circuit 1 and in the heat sink circuit 6 are throttled under emergency conditions and the circulation in the two circuits slows down. This increases the water temperature in the pre-cooler 2 and the intercooler 3, and the water begins to boil. Once dor pressure Ln the Zwlschenktthlkreislauf exceeds a predetermined value "the safety valve opens and allows water and vapor from the intermediate cooling circuit escape carry the Wiirme thereby to the atmosphere. At the same time, the emergency feed water pump 12, which has only a relatively low energy requirement, is switched on and the loss of the water or steam exiting via the safety valve 10 due to feed water supply from the emergency water tank 11 is eliminated. In the typical case, this container can hold enough water for 45

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Minutes of continuous cooling; contains @n "

In this way it is possible to extract the phenomenon of latent heat of vaporization from the core coolant and to considerably reduce the flow rate, for example, throughput in the intermediate coolant typiseherwaisa v> .m ® & m = n factor ensures the check valve 9 ;, which represents Wässerzufluß from the emergency tank 11 via the Yorküblsrr 2 and Ae n Zwisehönkühler 3 runs and therefore the · erzsagte steam ± n Rieh- tung gedrück- to the safety valve 10, fc is _a Dear · Zirkulierpusffiipia S is fed kaine Eaerg'i © & ns a & m Noteiaörgiöaggre "gat and the WasserstrSairaKAg by d @ n Wäraietauscher 5 stops o> d @ r is yet strong redusisi'iis Thus, the Wasseratröiaung 'lsi a & m Värmeaenkenkühlkreislauf δ come to a standstill, because k © iia © Wäraie von dom ¥ ärEie> Tausofeer 5 meiir needs to be dissipated, and also the energy requirement * of the pump © in the heat set coolant cooling circuit 6 therefore needs, just as little as the Eaiergji © be the Fump may © 8 _e dureii dae Notenergieaggr ^ IGAT applied zn werdesra.

It can be seen that the invention enables a considerable reduction in the design to be installed in the cooling system under emergency conditions with the help of a wall-mounted system for maintenance

Godparents icaasprUche %

109827/1009 ^BAD original

Claims (1)

Claims TΛ J Kühleyetem for a fluid-cooled core- ^ - ^ reactor mi + - a water-Zwischenktihlkreislauf for heat transfer from the Reaktorcore-Kühlmitiel to a further cooling circuit _f thereby geke η η ζ β i η e 1 that the coolant circuit (i) with o.a safety valve (1O) for draining water or steam from the cooling circuit (1) when the pressure in the intermediate cooling circuit (1) exceeds a predetermined range, and is provided with an emergency feed water supply device (11, 12, 13) , by means of which feed water is fed under pressure into the cooling circuit (i) Cumulative replacement for water or steam drained off through the safety valve (1O). 2 "Cooling system according to claim 1, characterized in that that the emergency feed water supply device (11 - 13) rait the secondary cooling circuit (i) at one point upstream the heat exchanger (2, 3) assigned to the reactor core cooling means is connected, and that the safety valve (10) downstream of this heat exchanger (2, 3) between the heat exchangers and the junction arranged with the emergency feed water supply device is. 3 «Cooling system according to claim 2, characterized in that in the intermediate cooling circuit (i) upstream of the connection the emergency feed water supply device (11 to 109827/1009 13) however stroiaalrrJäris «less safety valve (I ¹ () en. is· 10 9 8 2 7/1009