Research And Application Of Acidizing Plugging Removal Technique In Qian’an Oilfield

Qian’an oilfield is a kind of oil deposit has the character of low porosity, low permeability and non homogeneity. During the mining process, the formation is easy to block, so it is difficult to process. Using various acidizing system remove formation plugging, plugging technology to improve recovery efficiency, slow decline rate, is one of the important means of Jilin oilfield stable yield.This paper do the research to the plugging mechanism of the formation of Jilin oilfield, through make choice to the kinds of acidification system and evaluate the performance, we select four kind common, safety and environment kindly acidification system to make field research and valuate the effect. Aimed at the sandstone formation, blockage characteristics, it is better to use QCG-T compound acid-soil system; aim at the indication of oil and gas show well but formation testing poor, the same layer adjacent well has high output but the well has poor output, we should use TCAH-1 chelating acid system to deep acidification; aim at the low permeability tight sandstone reservoir blockage of lower permeability, we should use KTAH-1 biological chelating acid system; aim at the oil well of mining layer section and the layer has huge permeability difference, we should use SRZ foamed acid system to acidate the formation.The research shows that the QCG-T compound acid soil system is effective to oil well plugging has character of sandstone formation; the TCAH-1 chelating acid system and the KTAH-1 biological chelating acid system is effective to get rid of the deep plugging of formation; the SRZ foam acid system generated by the bubbles have temporary plugging effect, with more than mining zone, interlayer permeability difference big oil Wells can not only to solution plugging of high permeable zone,also can enter the low permeable formation, broken down on low permeable formation.