Oil Drilling

Innovative Applications of Polyaspartic Acid and Its Derivatives in Oil Exploration

As oil exploration and development advance into deeper and more complex formations, higher demands are placed on drilling fluids and oilfield chemicals. Polyaspartic acid (PASP), polysuccinimide (PSI), and polyepoxysuccinic acid (PESA), as environmentally friendly green chemicals, demonstrate unique application value in the oil exploration field. This article systematically introduces the application mechanisms and effects of these three materials in drilling fluids and enhanced oil recovery (EOR).

Product Characteristics

1. Polyaspartic Acid (PASP)

• Molecular Structure: Linear polymer with abundant carboxyl and amide groups

• Thermal Stability: Withstands temperatures above 150 ℃

• Biodegradability: >90% degradation rate within 28 days

• Inhibitory Performance: Excellent shale inhibition properties

2. Polysuccinimide (PSI)

• Structural Features: Precursor of PASP with reactive imide groups

• Reactivity: Easily modified through chemical reactions

• Thermal Stability: Excellent high-temperature resistance

3. Polyepoxysuccinic Acid (PESA)

• Molecular Features: Contains ether bonds and carboxyl groups

• Scale Inhibition: Outstanding performance against CaCO₃ and BaSO₄ scaling

• Environmental Friendliness: Non-toxic and readily biodegradable

Applications in Drilling Fluids

1. Shale Inhibitor
PASP inhibits shale hydration through the following mechanisms:

• Adsorbs onto shale surfaces to form a protective film

• Prevents water intrusion into shale bedding planes

• Suppresses ion exchange reactions
  At concentrations of 0.1–0.5%, shale recovery rates improve by 40–60%.

2. Fluid Loss Reducer
PSI reduces fluid loss by:

• Forming dense filter cakes

• Sealing micro-fractures in formations

• Adjusting mud cake permeability
  At dosages of 0.3–0.8%, API fluid loss decreases by 50–70%.

3. High-Temperature Stabilizer
PESA maintains drilling fluid performance in high-temperature environments by:

• Preserving molecular structural stability

• Retaining drilling fluid properties

• Preventing thermal degradation

Applications in Enhanced Oil Recovery (EOR)

1. Oil Displacement Agent
PASP functions as a surfactant to:

• Reduce oil–water interfacial tension

• Alter rock wettability

• Improve oil-washing efficiency
  At concentrations of 0.2–0.5%, recovery rates increase by 8–15%.

2. Scale Inhibitor
PESA provides excellent scale inhibition by:

• Suppressing inorganic salt deposition

• Preventing wellbore and pipeline scaling

• Maintaining smooth operation of water injection systems

3. Profile Control and Water Plugging Agent
Crosslinked products of PSI:

• Selectively block high-permeability zones

• Adjust injection profiles

• Improve sweep efficiency

Advantages of Application

1. Environmental Friendliness

• Excellent biodegradability

• Low ecological toxicity

• Compliance with environmental regulations

2. Superior Performance

• High tolerance to temperature and salinity

• Good compatibility with other additives

• Long-lasting and stable effects

3. Economic Efficiency

• Low dosage requirements

• High overall efficiency

• Reduced treatment costs

Conclusion

Polyaspartic acid and its derivatives, with excellent environmental compatibility and superior performance, hold broad application prospects in oil exploration. As technology continues to evolve, these green chemicals will not only ensure the effectiveness of oil exploration and development but also minimize environmental impacts, providing critical technical support for the sustainable development of the petroleum industry. Future efforts should focus on strengthening fundamental research and driving technological innovation to expand the applications of these materials into wider fields.