Cla-Web® stabilizing additives

Clay stabilization for low-permeability formations

In addition to temporary clay stabilization during the treatment, the Cla-Web additive provides long-lasting clay stabilization in low-permeability formations. The Cla-Web agent molecule is very small and can enter the matrix of low-permeability formations like tight sand and shale. The molecule is ion-exchange resistant, rendering treated clay minerals insensitive to water, further preventing clay swelling and dispersion.

Like the proven performance of our Cla-Sta family of compound additives, which are optimized for moderate-to-high permeability formations, Cla-Web additives work by adsorbing onto formation surfaces, altering clay particles to reduce their interaction with flowing fluids, even at high flow rates.

Using Halliburton’s proprietary RockPerm® clay control service, we can customize the design of your Cla-Web treatment to your reservoir. This process involves identifying the types of clay minerals and their relative concentrations in the formation.

Superior performance at lower concentrations

In low permeability formations, Cla-Web additives provide several performance improvements compared to current, widely used potassium chloride (KCl) substitutes:

• Superior performance at a lower concentration, compared to competitive KCl substitutes
• Improved environmental characteristics (not classified as a hazardous material under 49 CFR Part 173 – subpart D or under the United Nations recommendations)
• Renders water swelling clays insensitive to changes in water salinity, resulting in excellent sustained permeabilities
• Can be batch-mixed or metered on the fly as a liquid additive to eliminate the time required in dry mixing
• Applicable over bottomhole temperature range from 50 to 500°F (10 to 250°C)

Compatibility and treatment optimization

The performance of the Cla-Web additive is demonstrated using capillary suction time (CST) testing, commonly used to compare KCl substitutes used for temporary clay control. This test provides insight into relative performance among additives and can be used to help optimize treatment concentrations. Core and sand pack testing demonstrate that the Cla-Web agent is an effective clay stabilizer through its ability to render water-sensitive clay insensitive.

This means that variation in the ionic content of water will not cause clay swelling or dispersion. This reduces concern over matching fracturing treatment water to formation water and concerns around mixing different waters produced from various parts of the formation.

Capillary suction time (CST) and mechanical stability tests (MST) are also part of the RockPerm^® clay control service. Both provide rapid and inexpensive methods to help optimize a treatment for low to moderate water sensitivity. They require a small amount of formation material, such as drill cuttings or core sample fragments. These methods allow for relative comparisons of several competitive products.

Core testing is an additional service that provides the most authoritative data to base recommendations. These tests require that enough core samples are available to represent the formation statistically.

We use these results to provide recommendations on the optimal Cla-Web additive design and application method to maximize clay protection and productivity from the well.