Water-based fracturing fluid used for continental face shale gas fracturing and preparation method thereof

Abstract

The invention relates to a water-based fracturing fluid used for continental face shale gas fracturing and a preparation method thereof. The fracturing fluid comprises 0.02-0.1% of macromolecule polymer, 2-3% of clay stabilizer, 0.3-0.5% of discharge aiding agent, 0.1-0.3% of bactericide and the balance of water in mass percent. The preparation method of the fracturing fluid comprises the following steps of: 1) getting water in proportion in the formula of the fracturing fluid; 2) adding 0.02-0.1% of macromolecule polymer in mass percent, and stirring for 40 minutes; and 3) adding 2-3% of clay stabilizer in mass percent, and stirring for 10-15 minutes; and sequentially adding 0.1-0.3% of bactericide and 0.3-0.5% of discharge aiding agent in mass percent under a stirring condition, stirring for 15 minutes, and fully dissolving. The fracturing liquid provided by the invention can greatly reduce fracturing construction pump pressure and has the characteristics of low surface tension, good discharge aiding agent, strong clay stabilizing capability, strong sterilization capability and no precipitation or flocculate.

Description

technical field [0001] The invention relates to a water-based fracturing fluid for continental shale gas fracturing and a preparation method thereof. Background technique [0002] Shale gas is a kind of natural gas that occurs in interlayers of dark mudstone, high-carbon mudstone, shale and silty rocks. The reservoir lithology is tight, the permeability is extremely low, the gas saturation is low, and there is no natural productivity. Large-scale fracture network fracturing is required to obtain industrial gas flow, and shale gas development is in the exploratory stage in my country. [0003] According to the experience of developing marine shale gas in the United States, water-based gel fracturing fluid and foam fracturing fluid were initially used for large-scale fracturing stimulation, and good stimulation effects were obtained, but the final economic benefits were not good due to high costs , until 1997, the implementation of large-scale fracturing operations of this typ...

AI Technical Summary

Problems solved by technology

[0003] According to the experience of developing marine shale gas in the United States, water-based gel fracturing fluid and foam fracturing fluid were initially used for large-scale fracturing stimulation, and good stimulation effects were obtained, but the final economic benefits were not good due to high costs , until 1997, the implementation of large-scale fracturing operations of this type of fracturing fluid system was stopped; after 1998, large-scale fracturing operations using slick water (also known as drag-reducing water) fracturing fluids were successfully carried out. Compared with large-scale gel fracturing The cost of slick water fracturing has dropped by more than 30%, making the exploitation of shale gas profitable. So far, slick water fracturing fluid has become the most commonly used fracturing fluid system for shale gas development in the United States