绥中36-1油田酸化解堵技术研究

RESEARCH ON THE ACIDIZING PLUG-REMOVAL TECHNIQUES USED FOR SUIZHONG 36-1 OIL FIELD

绥中 36 - 1油田的多口井在钻井完井过程中遭受了较严重的伤害 ,为了了解储层在钻井完井过程中受到了哪些污染 ,以及受到污染的程度 ,我们开展了绥中 36 - 1油田酸化技术研究 ,力求解除储层受到的伤害 ,改善近井地带渗流环境。文章从室内实验研究出发 ,探讨了储层受到污染的原因 ,找出了不同污染类型及其伤害程度 ,而后应用土酸体系和我们研制的PEFA酸液体系进行了酸化解堵实验 (实验在从美国CoreLab公司进口的RP TA - 12 0实验仪上完成 ) ,实验表明PEFA酸液体系是一种低伤害酸液体系 ,解堵效率高 ,与岩石反应后生成的残酸对储层伤害小 (与常规土酸比较 )。经过现场两口井的实验 ,证明该酸液体系能有效解除储层在钻井完井过程中的伤害 。

A relative serious damage occurred in the processes of drilling and completion of many wells in Suizhong 36-1 oil field.In order to remove reservoir's being damaged and to improve the percolation conditions near the borehole wells,a research on the acidizing techniques used for Suizhong 36-1 oil field was carried out on the basis of examining what pollutants making the reservoir be contaminated and its contaminated degree.According to the experimental research results,the reasons of reservoir's being contaminated are discussed and the various pollution typs and the degrees polluted by them are revealed in the paper.All acidizing plug removal experiments of clay acid system and PEFA acid system developed by the authors were carried out and accomplished by use of the RPTA-120 equipment imported from the Core Lab Company in USA.Through experimenting,it is indicated that the PEFA acid system is of these advantages such as low damage and high plug removal effectiveness.The degree of reservoir's being damaged by the residual acid generated after the reaction of PEFA acid to rocks was less than that by the conventional clay acid.Through the on site experiments in two wells,it was proved that the reservoir damage caused in the processes of drilling and completion can be effectively released by the PEFA acid system,thus recovering and raising oil well productivity.