Luda 4-2

Location and Geographical Context

The Luda 4-2 Oil Field is located in the Bohai Sea, China. This is an offshore oil field, which presents unique operational and environmental challenges.

The field is currently operational, with production activities underway. CNOOC Ltd, the operator, has announced the start of oil production from this field.

Field Development: The project involves the development of offshore oil fields, which typically includes the installation of wellhead platforms, production and storage facilities, and a network of production wells. For similar fields in the region, such as Luda 27-2 and LD 32-2, there are two wellhead platforms, one production and storage platform, and multiple production wells (e.g., 34 production wells in the case of Luda 27-2 and LD 32-2).

Modes of Operation: The well operations at Luda 4-2 would likely include various modes such as producing (oil), possibly injecting (for enhanced oil recovery), and treating (for maintenance and stimulation activities like acidizing or fracturing). Each mode has distinct temperature-depth profiles that are crucial for designing the completion and selecting appropriate packers.

Shut-in Profile: When the well is shut in, the temperature profile will move towards the natural geothermal gradient, with temperature increasing with depth.
Producing Profile: During production, the wellhead temperature will be lower than the bottomhole temperature (BHT) due to factors like the flow rate, gas/liquid ratio, and thermal heat transfer rates.
Injecting/Treating Profile: For injection or treating operations, the temperature profile will be influenced by the temperature of the injected fluid and the flow rate, with minimal heat pickup by the fluid as it moves down the tubing.

Well Design and Completion: The design of the wells and the selection of packers must consider the anticipated temperature profiles for each operational mode to ensure the integrity and longevity of the tubing and packer system.
Pressure Profiles: The pressure profiles will also vary depending on the mode of operation, with different profiles for shut-in, producing, injecting, and treating operations. These profiles are important for understanding the well's behavior and managing pressures effectively.

Offshore operations in the Bohai Sea must comply with local and international environmental regulations. This includes measures to prevent oil spills, manage waste, and protect marine ecosystems.

The Luda 4-2 Oil Field is part of CNOOC Ltd's broader strategy to increase oil and gas production from offshore fields in China. The start of production at this field, along with other fields, is expected to contribute significantly to China's energy security and CNOOC's production targets.