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As carbonate reservoir stimulation becomes increasingly complex, operators are looking for acid systems that not only improve stimulation efficiency but also minimize formation damage and equipment corrosion. Among the available technologies, VES (Viscoelastic Surfactant) Diverting Acid has become one of the most effective solutions for improving acid placement in heterogeneous formations.

However, many engineers focus primarily on the diverting performance of the VES system while overlooking another equally important factor—corrosion protection.

An effective VES acid treatment is not simply a combination of hydrochloric acid and viscoelastic surfactants. It also requires a corrosion inhibitor specifically designed to remain fully compatible with the VES system throughout the stimulation process.

Why Conventional Corrosion Inhibitors Often Fail in VES Acid Systems

Traditional acidizing corrosion inhibitors were originally developed for conventional hydrochloric acid systems. Many of these formulations contain solvents, surfactants, or film-forming agents that may interfere with the rheological behavior of viscoelastic surfactants.

When an incompatible corrosion inhibitor is added to a VES diverting acid system, operators may experience:

• Reduced diverting efficiency
• Lower fluid viscosity
• Premature viscosity loss at elevated temperatures
• Poor compatibility during acid spending
• Reduced stimulation effectiveness

For this reason, selecting a corrosion inhibitor solely based on corrosion performance is no longer sufficient. Compatibility with the VES system has become an equally important evaluation criterion.

The Importance of a Compatible Corrosion Inhibitor

A corrosion inhibitor developed specifically for VES acid systems should perform two critical functions simultaneously:

First, it must effectively protect tubing, casing, coiled tubing, pumps, and other downhole equipment from aggressive acid corrosion.

Second, it must preserve the rheological properties of the VES diverting acid, allowing the fluid to maintain its viscosity and diversion capability throughout the treatment.

Only when these two objectives are achieved can operators obtain maximum stimulation efficiency while protecting valuable production equipment.

The All-Chem Integrated VES Acid Solution

Sichuan All-Chem Chemical Co., Ltd. supplies an integrated solution for VES acidizing applications consisting of:

AC-VES21 – Viscoelastic Surfactant Diverting Agent

and

AC-CIV3 – Corrosion Inhibitor Compatible with AC-VES21

Unlike conventional corrosion inhibitors designed for general acidizing operations, AC-CIV3 has been formulated specifically for compatibility with AC-VES21, allowing both products to work together without negatively affecting fluid performance.

Learn more about our AC-VES21 Viscoelastic Surfactant Diverting Agent:

To achieve the best acidizing performance, a VES diverting agent should always be paired with a corrosion inhibitor specifically formulated for VES acid systems. An incompatible corrosion inhibitor may reduce fluid viscosity, affect diverting efficiency, or even shorten the effective treatment time. Therefore, selecting a corrosion inhibitor that offers both excellent corrosion protection and full compatibility with the VES system is essential for successful acidizing operations.

For this purpose, Sichuan All-Chem has developed AC-CIV3 Corrosion Inhibitor , a dedicated corrosion inhibitor engineered to work seamlessly with AC-VES21. The product provides outstanding corrosion protection while maintaining the rheological stability and diverting performance of the VES acid system.

Learn more about our AC-CIV3 Corrosion Inhibitor.

Advantages of the Combined System

Using AC-VES21 together with AC-CIV3 provides several important operational advantages:

• Excellent compatibility between the diverting agent and corrosion inhibitor
• Stable viscosity during acidizing operations
• Reliable corrosion protection for tubing and downhole equipment
• Effective acid diversion into low-permeability zones
• Reduced risk of premature fluid degradation
• Suitable for a wide range of carbonate acidizing applications

By optimizing both diversion performance and corrosion protection, the integrated system helps improve stimulation efficiency while reducing operational risks.

Selecting a Corrosion Inhibitor for VES Acidizing

When evaluating corrosion inhibitors for VES acid systems, operators should consider more than corrosion rate alone.

Important evaluation criteria include:

• Compatibility with viscoelastic surfactants
• Thermal stability under reservoir conditions
• Acid compatibility
• Corrosion protection efficiency
• Fluid viscosity retention
• Emulsion tendency after acid spending
• Environmental performance

A well-designed corrosion inhibitor should support—not interfere with—the performance of the entire acidizing system.

Technical Support and Customized Formulations

Reservoir temperature, acid concentration, completion materials, and stimulation design vary significantly from one oilfield to another.

To meet these different operating conditions, Sichuan All-Chem provides customized formulations of both VES diverting agents and compatible corrosion inhibitors. Product formulations can be optimized according to:

• Acid concentration
• Reservoir temperature
• Contact time
• Tubular metallurgy
• Operational requirements
• Customer laboratory evaluation results

Our technical team works closely with customers throughout laboratory testing and field evaluation to ensure reliable performance under actual operating conditions.

Partner with Sichuan All-Chem

Successful acid stimulation depends on the compatibility of every chemical in the system—not simply the performance of individual additives.

By combining AC-VES21 Viscoelastic Surfactant Diverting Agent with the specially developed AC-CIV3 Corrosion Inhibitor, Sichuan All-Chem provides an integrated solution that enhances diversion efficiency while delivering dependable corrosion protection.

If you are seeking a reliable supplier of VES diverting acid additives or corrosion inhibitors compatible with VES systems, contact our technical team to discuss your application requirements and customized solutions.