Case Study: Beyond Acid: Advancing Unconventional Reservoir Recovery with Chemical Restimulation

_ As unconventional reservoirs mature, operators are increasingly looking for innovative methods to enhance production from existing wells. Traditional stimulation techniques, such as acid treatments, have been borrowed from conventional reservoirs, but their effectiveness in tight shale formations is often limited. An alternative approach gaining traction is chemical restimulation, which aims to improve well productivity by addressing near-wellbore damage, restoring fracture conductivity, and optimizing fluid flow through targeted chemical treatments. Unlike acid jobs, which primarily rely on wellbore scale dissolution, chemical restimulation can be tailored to the specific conditions of a reservoir, making it a more versatile and scalable solution. By utilizing low dose rates of chemistry, larger volumes can economically be injected allowing for contact of the fractures and facture-matrix interface. This article explores the advantages of chemical restimulation over acid treatments, highlighting how it can improve production economics and extend the productive life of unconventional wells. Chemical Restimulation vs. Acid Jobs As operators manage their well inventory development more carefully, the industry seeks innovative methods to increase production from existing wells. This has led some well operators to borrow methods from conventional reservoirs and attempt to use acid treatments to stimulate production on existing wells. Acid, particularly hydrochloric acid (HCl), has an extensive history of being used for stimulation of conventional carbonate reservoirs and to dissolve acid-soluble scales in the wellbore. Translating the use of acid to stimulate horizontal, multistage fractured wells in tight formations presents numerous challenges.