GB908925A - Nuclear power plants - Google Patents

Abstract

908,925. Nuclear power plant. SULZER FRERES S.A. Aug. 4, 1961 [Sept. 21, 1960], No. 28464/61. Class 39 (4). The core of a nuclear reactor is cooled by a vaporous or gaseous medium, e.g. steam, which is divided into two streams, one stream being supplied to a prime mover, expanded therein, condensed, pressurized by a pump and then passed through a heat exchanger as a secondary medium, while the other stream is passed as the primary medium through the heat exchanger and is then circulated by a blower before joining the first stream downstream of the blower. The object of the invention is to reduce the blower power. In Fig. 2, the reactor 1 supplies steam to the distributing valve 2 which divides the coolant into a first stream which operates the turbine 4 before being condensed in the condenser 5, pressurized by a pump 6 and partially vaporized in the heat exchanger 7. The second stream passes through the heat exchanger 7 and is circulated by the blowers 9a and 9b and joins the first stream in the pipe 12. As the central part of the core is hotter than the periphery then the use of the two blowers ensures that the coolant flows faster through this central part than through the periphery which is fed only from the blower 9a via the pipe 11. Fig. 1 (not shown) differs from Fig. 2 in that it has only one blower and no pipe 11. In Fig. 3, the steam is divided from the junctions 13 so that steam from the periphery of the core, which is hotter than the steam from the central part, drives the turbine. Fig. 4 (not shown) combines the features of Fig. 2 and 3. In Fig. 6, the turbine feed steam is taken from the junction 2. Fig. 5 (not shown) differs from Fig. 6 in that the steam is divided just before entering the reactor. Similarly in Fig. 7 (not shown), the steam is divided upstream of the heat exchanger. In Fig. 8, a two-stage turbine is used with intermediate reheating of the turbine steam in the reactor. The cooling of the turbine steam may be varied by injecting a small proportion of the feedwater at a point 16. In Fig. 9, the whole quantity of steam passes through the core in two serially connected passages. The steam can be cooled in an extra heat exchanger 7a after the first passage; alternatively, as in Fig. 10 (not shown), the steam can pass through the first time without cooling.