Re-Fracturing Technique Using Forced Fracture Re-Orientation of Low Production Oil and Gas Wells

To improve the productivity of low production gas and oil wells and to delay or mitigate the post-fracturing production decline rate,a re-fracturing technique using forced fracture re-orientation to enlarge the stimulated volume was proposed based on the analysis of the principle of the re-fracturing technique and the existing problems.By first calculating the maximum pressure for re-orientation,the newly-constituted water soluble diverting agent was applied to build the pressure in original fractures until the pressure was high enough to create a new fracture,thereby accomplishing the objective to forcibly divert fractures and enlarge fractured volume.This technique has been put into practice in three wells of the DJ Gasfield,resulting in the average wellhead pressure increasing up to 12.8 MPa and the average single-well gas production increasing by 3 000 m3/d after the adding the diverting agent.The research and application results indicated that this re-fracturing technique using forced fracture re-orientation has the technical advantages such as achieving a high success rate of re-orientation operation,reducing the amount of diverting agent used,being suitable for extensive applications,with an obvious production increase.Thus the re-fracture technique using forced fracture re-orientation provides a new technical method in restimulation of low production wells.