RIASSUNTO
ABSTRACT
The importance of natural gas in the European Countries has grown significantly since the first years of Millennium 2000. The increasing popularity of this fuel source is mainly related to relevant low emissions to the environment and its flexibility in energy production. In order to meet this demand, the most efficient transport system is recognised to be high capacity pipelines, importing natural gas from the big gas reserves in Russia. As part of this scenario, a dedicated large diameter offshore pipeline system called Nord Stream Project (NSP), has been designed and installed in the Baltic Sea. The NSP export system is defined as the two 48"" pipelines which will export gas from Portovaya Bay, near Vyborg, North of St. Petersburg (in Russia), crossing the Gulf of Finland and the Baltic Sea, up to a landfall area at Greifswald in Germany. A dedicated Company, the Nord Stream AG, has been established for the planning, construction and subsequent operation of the NSP pipelines, which is an international joint venture of OAO Gazprom, BASF/Wintershall Holding AG, E.ON Ruhrgas, GDF SUEZ S.A. and N.V. Nederlandse Gasunie. The two pipelines run almost parallel along the Baltic Sea, where the offshore section has a total length of approximately 1222 km each. The following two dry parts of the offshore pipeline system are also included, approximately 0.5km in Germany, up to the Greifswald pig receiving facilities, and approximately 1.5km in Russia, up to the pig launching facilities down stream the Portovaya Bay compression station. In addition to Russia and Germany, the pipeline route crosses three European countries Territorial Waters (TW) and/or as Exclusive Economic Zones (EEZ) which include Finland, Sweden and Denmark. The total capacity of the two pipelines will be 55 BCM/year at reference conditions of 20°C and 1atm. The technical concept is by means of a Segmented Pressure system, with design pressures of 220/200/177 barg (three pressure segments).