Atucha-2 reactor

The production costs of a MZFR type fuel element which also apply to the fuel of the Atucha reactor amount at the present to approximately 55 of the total costs, with the balance of 4-5 for uranium and Zlrcaloy. It is thought that a significant reduction In future production costs is possible by rationalized manufacturing methods and standardized test procedures which go hand in hand with Increased production capacities. The uranium costs may be assumed to remain constant in the period under review. In the long run it is therefore advisable to choose that fuel element design which will benefit most by the expected production cost reduction. 

HWRs of the pressure vessel type have been designed and constructed in Sweden, Germany, and Argentina. The main references of this line are the Agesta reactor in Sweden (shutdown), the MZFR reactor in Germany, and the Atucha-1 and Atucha-2 reactors in Argentina. 

The 57-MWe MZFR reactor was built by Siemens-KWU at the Karlsruhe Research Center for limited electricity supply and district heating. It was the prototype for the Atucha-1 and Atucha-2 reactors built in Argentina. The principal features are similar to those incorporated in Atucha-1. 

The HTS consists of the reactor vessel, two steam generators, two primary pumps, and the pressurizer that keeps pressure at approximately 11.65 MPa. The system has two loops, and for Atucha-1 the exit temperature from fhe pressure vessel is 300°C and the inlet temperature of the return coolant into the pressure vessel is 265°C. 

Atucha-2 is a larger version of Atucha-1 with more charmels. Construction of the reactor was delayed for a number of years because of limitations in funding, but is now nearing completion and reached full power early in 2015. 

Use of well-proven special heavy-water equipment and systems from the heavy-water reactor power plants MZFR (multi-purpose-research reactor, Karlsruhe, FRG, 58 MW) and Atucha I (Argentina, 367 MW(e)). 

KWU PHWR plants have accumulated 30 reactor years of experience. MZFR (PHWR) has accumulated load factor of 62.6% until the end of 1983. ATUCHA-I is connected to the grid since 1974-06. It has accumulated 9 years of reactor years with a cumulative load factor of 78.4% until the end of 1983. 

Several procedures have been developed to assure quality of the reliability data of NPPs. The utility have been recording reliability data on many areas of reactor plant from more than ten years, in particular on Atucha I PHWR NPP, with more than 20 years of operating experience and unique design. Such data retrieval was increased with the development of the PSA taking into account the scope and the applications of such assessment. Realistic input data for PSA models were necessary, in particular to include common cause failures (CCF) data due to its dominant risk factor on PSA s. The basis and the clear justification of safety related component data is a regulatory requirement. 

The experience gained with the MZFR and the most remarkable success of H2O pressurized water reactors provided a strong Inducement to develop the MZFR concept of a natural uranium fuelled D2O-PWR up to an economic size. This had been achieved when we tendered for the 320 MW Atucha unit in the Argentine last year. 

The core dimensions characteristic of natural uranium reactors require pressure vessels of large diameter. Six years ago, when the design of the MZFR vessel was established, Its parameters corresponded to the production capabilities at that time. Those limitations have meanwhile been transgressed and are no longer valid. The Steel vessel for the Atucha power plant corresponds to an electrical output of... 

---