Study of retarded agent performance in acid fracturing technique

Abstract

Acid fracturing is a well stimulation technique mainly applied to carbonate formations. It is employed to bypass existing formation damage or stimulate an undamaged formation in low permeability reservoirs. During the injection of the acid, it reacts immediately with the formation and for this reason using OPR technology to retard the reaction of the acid with the formation to ensure a long penetration of the acid and gives better results and a best recuperation of the hydrocarbons. In this study a comparison between HCl and retarded agent will be studied including laboratory experiments. The results obtained from these experiences prove that the retarded agent retards the rate of reaction of the acid, after one hour the solubility of carbonate in OPR is 45% and the solubility of the carbonate in HCl is 67%.