Toward mechanistic understanding the effect of an external MF on the HCl solutions: Experimental study and modelling using RSM

Hydrochloric acid has been used as the main acidizing fluid in petroleum and gas industry. Rapid spending of the acid with carbonates avoids deeper penetration of the acid into the formations. The present work investigates the influences of magnetic field on reaction rate of hydrochloric acid in order to improve acidizing performance. The effects of an external variable magnetic field (MF) on ۵, ۱۰ and ۱۵ wt.% (۱.۵, ۳ and ۴.۵ M) HCl solutions behaviour are studied at different conditions. The changed rules of the pH of magnetized HCl compared to that of normal HCl were measured. Response surface methodology (RSM) design of experiment (DoE) has been used to study and model the effects of MF intensity and concentration of acid as well as the effect of elapsed time. The experimental results show that the MF decreases [H+] concentration of HCl after magnetization up to ۴۲%. Growing MF intensity and concentration of acid increase the effect of magnetic treatment. The results also demonstrated that acid preserves its magnetic memory during time. Due to reduction of HCl reactions rate under magnetization process, it can be proposed that magnetized HCl is a cost effective and reliable alternative of retarder acids in matrix acidizing of hydrocarbon (petroleum and gas) wells.

Keywords:

Magnetic Field , Hydrochloric Acid , pH , Reaction Rate , Design of Experiments , Response Surface Methodology.