High Porosity And Permeability Sandstone Reservoirs In The Deep Of The Fluoroborate Acidification Technology Research And Field Applications

According to the characters of the formation with higher porosity and permeability, this paper presents the research of the mechanism of stimulation, optimizing the acid fluid system, deep acidizing technology of fluoboric acid(HBF4), acid fluid diverting, optimizing the design and stimulation, and have fully understanding about acidizing mechanism and the damage factor. The research accomplishment of acid fluid system, acidizing technology and mathematical simulation not only formed acidizing technology and technique of nonhomogeneous sandstone reservoirs with high porosity and high permeability, but also provided some experiences for the similar conditions in the whole world. The application of research accomplishments had gained a remarkable economic beneficial result. There is the groundwork that the thesis finishes:Ⅰ Research the mechanism of stimulation of nonhomogeneous sandstone reservoirs with high porosity and high permeability. According to the reservoir characters and the mechanism of damage, the acid fluid system has been selected, which adapted to nonhomogeneous sandstone reservoirs with high porosity and high permeability.Ⅱ The deep acidizing technology of HBF4 had been researched in detail. The hydrolysis of HBF4, the dissolubility and reaction rate of HBF4 with clay, the effect on clay swelling and stabilization of fine particle migration of HBF4 and the operational procedure for deep penetration of HBF4 have been studied in detail.Ⅲ Based on the character of reservoir permeability and pore throat distribution, the diverting technique which main consist of the chemical particle diverting technique and the diverting material which satisfy the physical chemistry property had been sieved. The diverting laboratory experiment, effect evaluation and diverting dynamic simulation have been studied.Ⅳ In consideration of temperature in well bore and formation, multiplayer, multicomponent mineral and formation damage, simultaneously, continually hydrolyzing of HBF4, a new mathematical model and a numerical model of sandstone HBF4 acidizing are developed in this paper. A calculation program on optimizing design for HBF4 diverting acidizing of nonhomogeneous sandstone reservoirs with high porosity and high permeability. The result of many calculations showed this program was reliable and thee result was reasonable. This program can be used as sandstone acidizing design and simulating acidizing process and forecasting productivity and diverting dynamic simulation and optimizing the treatment parameter.