Product

Multi-Factor Collaborative Heavy Oil Thermal Recovery Upgrading and Production Enhancement Technology

Core Production Challenges

Shallow heavy oil reservoirs have loose rock cementation, leading to sand production that blocks flow channels and causes tool wear. With crude viscosity exceeding 5,000 mPa·s, cold production is extremely difficult due to high seepage resistance.

Limitations of Traditional Technologies

Most conventional methods use a single displacement agent or viscosity reduction technique, failing to balance viscosity reduction with energy enhancement. They also suffer from low thermal efficiency, limited sweep range, high water consumption, and poor adaptability to sensitive formations.

Significance of Technology Development

This innovation overcomes the limitations of single-approach technologies by establishing a "thermal–chemical–gas–sand control" collaborative system, integrating viscosity reduction, energy enhancement, plugging removal, and sand control, thereby filling a technological gap in the efficient development of complex heavy oil reservoirs.

Sand Control Barrier Construction

High-temperature coated sand technology creates a high-permeability sand control barrier in the near-wellbore area, maintaining open flow channels.

Deep Heating Core

Injecting nitrogen at 300–350°C creates a deep thermal field that reduces heavy oil viscosity.

Energy Replenishment Assurance

Leveraging nitrogen expansion to recharge formation energy, prevent bottom water coning, and improve sand control barrier stability.

Plug Removal and Drainage Assistance

The dual percolation action of heat and nitrogen removes wax, scale, and blockages, minimizing formation damage.

Micro-scale effects

Thermal-Gas Synergistic Viscosity Reduction: Each 50°C temperature rise reduces viscosity several-fold; miscible blending enhances interfacial tension by >40%.
Thermal Cracking: At >300°C, heavy oil macromolecules crack into light hydrocarbons; nitrogen inhibits oxidation and coking.
Pore Unblocking: Heat melts organics, nitrogen flushes out plugs, eliminating water locks and emulsion locks.

Macro-scale effects

Multi-Drive Synergy: Combining thermal expansion, elastic gas drive, and gravity drainage improves vertical sweep efficiency by ≥30%.
Mobility Control: Suppresses gas channeling and fingering, extending areal sweep coverage by 60–150 m.

Cyclic Enhancement Mechanism

Injection Phase (3–5 days): Quickly reduces viscosity and replenishes energy, creating a thermal-gas-pressure coupling system.
Soaking Phase (3–5 days): Heat diffuses and nitrogen separates, ensuring uniform reaction.
Production Phase: Multiple energy sources are released, boosting oil production rate by 5–8 times.