Study On Technical Limits And Crack Parameters Optimization Of Increasing Production Measures In Tight Sandstone Gas Reservoirs

There is a huge amount of tight sandstone gas resources in western Sichuan, the tight gas reservoirs with characteristics of low porosity and permeability. Production on the face of difficulties, the traditional method of fracturing stimulation can’t greatly increase the production capacity and maintain the production cycle of the horizontal wells. For reservoir characteristics of tight sandstone gas reservoirs with low porosity and low permeability, it is necessary to form a stimulation method for producing a suitable technique such gas reservoirs.At present the shale gas stimulation (SRV) can greatly improve the productivity of extremely low permeability shale gas reservoirs. The fracturing treatment is based on the Segmentation and multi-cluster perforation, which form a map cracking near the wellbore to improve the level of economic of the shale gas wells. In theory, the same technology can also be used in wells transformation of low permeability tight gas (sandstone) reservoir. By a similar fracturing technology, not only can improve the situation of tight gas production wells, but also helps to understand the production characteristics of such tight gas reservoir. For the main problems belong to Optimization of the fracture parameters in tight gas reservoir, as an example, this thesis takes the Western Sichuan Xinma-Shifang gas Field of Penglaizheng formation, Employing numerical simulation method, the effect of permeability of tight sandstone gas reservoir (1mD-1nD).the number of fractures(40、20、10、5), and the fracture conductivity on the production of tight gas reservoirs are discussed. Based on the above factors to the limit of the reservoir permeability gas reservoir stimulation is divided into three areas:"typical shale stimulation zone","Tight gas shale-like stimulation zone" and "typical tight stimulation zone". Hence the technology limits of applying shale gas reservoir stimulation to ultra low permeability of tight sandstone gas reservoirs are detenrrined by the above factors. It is applicable to permeability range in shale gas reservoir stimulation, thus guiding the optimum of tight gas reservoir fracturing stimulation more reasonably.Referring to the reservoir permeability limits on this basis to optimize horizontal well volume stimulation parameters within the "Tight gas shale-like stimulation zone". Take the Western Sichuan Xinma-Shifang gas Field of Xinma-Shifang formation as an example, with the initial production and20years of recovery percent as the evaluation index of the horizontal well. By using numerical simulation software to optimize the fracture parameters (horizontal length, perforating number, hole spacing, number of clusters, cluster spacing, the number of segments, fracture half-length), which carry out the suitable fracture parameters in Xinma-Shifang gas Field of Penglaizheng reservoir. This greatly improving the production capacity and stable production period of the low permeability sandstone gas reservoir for the development of such gas reservoirs proposed a reasonable and practical technique.