Patent ID: 10822937

Abstract:
The present invention relates to a fracturing method for providing fractures in a formation downhole for optimising hydro-carbon production, such as gas or shale gas production, in a well having a well tubular metal structure comprising several self-closing flow assemblies, each self-closing flow assembly comprising a sleeve which is movable along a longitudinal axis of the well tubular metal structure for opening or closing a port in the well tubular metal structure. The method comprises providing fracturing fluid derived from in situ hydro-carbons; submerging an activation device into the well tubular metal structure; pressurising the well tubular metal structure by means of the fracturing fluid derived from in situ hydro-carbons for moving the activation device towards a first self-closing flow assembly; engaging the sleeve of the first self-closing flow assembly by means of the activation device; further pressurising the well tubular metal structure by means of the fracturing fluid derived from in situ hydro-carbons for moving the sleeve of the first self-closing flow assembly and thereby opening the port; injecting the fracturing fluid derived from in situ hydr-carbons through the port of the first self-closing flow assembly for providing fractures in the formation; decreasing a pressure of the fracturing fluid by 0.5-20% for releasing the activation device from the first self-closing flow assembly, thereby closing the port; and moving the activation device by means of pressurised fracturing fluid for engaging a second self-closing flow assembly.