Western Sichuan Xujiahe Dense Gas Reservoir Fracturing The Transformation Of Key Technologies

Fracturing is a effective method to enhance the production of the low permeability and compact reservoir, and is widely used in the oil field. The permeability of the Xujiahe gas reservoir is low and the production is low, therefore, it will benefit after fracturing treatment. However, Xujiahe gas reservoir is a high temperature, high pressure, extra-deep, high fracturing pressure and extra-compact reservoir, which enables the fracturing fluids to have a great effect on the formation, and it is difficult to fracturing the formation, therefore there are new requirement for the fracturing materials, fracturing techniques and fracturing equipments. This paper researches the key technique of the fracturing treatment according to the problem of the Xujiahe gas reservoir and tries to form a fracturing technique suited for the Xujiahe gas reservoir.Firstly, we research the character of the gas reservoir and geology, and analysis the requirement and difficult of the fracturing and the key problem of the fracturing and come up with the solving method. Based on the research of the fracturing method of the Xujiahe gas reservoir, we conduct the propping agent optimization.To overcome the high fracturing pressure and the difficult of the formation, we develop a new pretreatment acid. This paper focuses on the system of the fracturing fluids, analyze and evaluate the sensitivity of the reservoir based on the room experiment, analyze the requirement of the reservoir sensitivity to the fracturing additive and pick out the good additive, evaluate the property of the fracturing fluids, including the mensuration of the fracuting fluids rheology, cracking, the compatibility of the fracturing fluids to the formation fluids and so on, and develop a fracturing fluid which has better restrain on the swelling of the clay and lower friction.The three different fluid systems (which contains pppant) and acid systems have been applied in oilfield, and the result is effective ,which illustrates that the three fluid systems(contains proppants) and acid systems be able to meet the demand of fracturing stimulation for Xujiahe gas pool.