Acidizing Design for Sandstone and Carbonate Formation

• Main Author: Muhammad Prasandha, Fateh
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/42407
• Institution: Institut Teknologi Bandung

Improving or restoring permeability of formation near wellbore is the intent of acidizing by enlarging the pore throats or removing damage in formation. In the early days, acidizing was very successful to enhance production in carbonate formation. Attention of matrix acidizing then shifted to sandstone formation with use of hydrofluoric acid (McLeod, 1984). Today, acid that commonly being used for acidizing include Hydrochloric Acid (HCl), Hydrochloric/Hydrofluoric Acid (HCl-HF), Formic Acid, Acetic Acid, and inorganic-organic acids (Coulter, 1999). Implementation of acidizing for both sandstone formation and carbonate formation requires different acid system because of different objective that wanted to be achieved, but the same practices can be applied (McLeod, 1984). The intent of acidizing in sandstone formation is to reduce the near-wellbore damage that caused by drilling and completion activity, while acidizing in carbonate formation is to create wormhole so that hydrocarbon can flow through wormhole (Guo, 2006). Economides (Economides, 2000) has already develop the flowchart to determine and design the acid needs for both carbonate and sandstone formation, including the selection of diversion. Recommended procedure for acidizing already developed by McLeod (McLeod, 1984). Both flowchart and procedure will become reference in designing the acidizing program for this study. This study will discuss about acidizing design for both sandstone and carbonate formation using calculation software that will be developed at the same time. Based on Mcleod procedure (McLeod, 1984), safe injection pressure and safe injection rate will be calculated to ensure the safe operation, then using fluid selection flowchart by Economides (Economides, 2000), fluid stage will be determined including concentration and volume required. The outcomes from this study will be Safe injection pressure, safe injection rate, fluid stage, volume required for each stage and acid concentration.