Increasing Productivity of Tight-Gas Wells by More Than 30% with Integrated Approach to Well Construction and Stimulation: Case Study

Abstract

E&P operating companies starting develop deeper production intervals with poorer formation properties due to depletion of the upper productive layers. This is a global trend worldwide. In connection with this it is very critical to optimize well construction and at the same time increase productivity of wells.Purpose to this work was to increase the productivity of six deviated gas condensate wells drilled for the achimov tight-gas deposits of the Urengoy gas condensate field. Integrated approach to well construction, completion and two-stage stimulation as well as the other technologies were used In order to achieve high production objectives.Because of the complex geological conditions of the achimov formation associated with the presence of abnormal pressure, narrow driling window, construction and completion of wells was associated with the risk of complications and emergencies.The paper describes an integrated project approach to planning, construction and the stimulation of the six wells in low permeable gas-condensate formation.The following technologies had been used during the wells construction: improved design of well completion (retrievable packer, the use of "floating" of the sealing arrangement, the use of the landing nipple below the packer to be able to cut off the producing formation, the use of premium gastight connections). Expanded set of logging (standard logging, NMR (Nuclear Magnetic Resonance), crossdipole acoustic measurements), a special thee component cement slurry, fracturing technology with high conductive channels, coil tubing service and drilling pipes make up.Due to integrated approach and new technology involved in well construction and completion of the six-deviated wells, construction time reduced and wells productivity increased by 30%. Urengoyskoe gas condensate fieldUrengoyskoe gas condensate field is supergiant gas field, third in the world by reserves, which is achieving 10 trillion of cubic meters (10 13 m 3 ). This field located in Yamalo-Nenetskiy area of Tyumen region of Russia, slightly to the south from polar Ural. Please see Fig. 1 Urengoyskoe gas field started developing at 1966 and it is more than 45 years in production. The length from south to north is 220 km and area of gas field 6 000 square kilometers.