Secondary extraction of petroleum

SECONDARY EXTRACTION OF PETROLEUM (EN: secondary oil production; DE: Sekundarerdolforderung; FR: production secondaire du petrole; ES: explotacion secundaria de petroleo; RU: вторичная добыча нефти) is the development of the energetically depleted petroleum layers, using the injection of the water or gas into these layers. The difference of the secondary extraction of petroleum versus the development with the maintenance of the layer pressure is the introduction of the energy into the layer after the depletion of its own energy. The physical essence of the displacement of the petroleum from the layer is the same in the both cases. Within the USSR, they used the secondary extraction of petroleum since the 1947 at the energetically depleted petroleum fields within the old petroleum-extracting regions, mainly within the Azerbaijan SSR. In association with the wide distribution of the methods for the maintenance of the layer pressure (85% of the total extraction of petroleum), the term "secondary extraction of petroleum" has lost its significance within the USSR.

Within the USA, there is also understood as the secondary extraction of petroleum the corresponding development of both the depleted and non-depleted layers, which is following at once after the period of the primary extraction at any of its stages.