China's first deepwater oil field redevelopment project has been fully commissioned, and our company's hydrocyclones have been deployed in it！

On December 14, China National Offshore Oil Corporation (CNOOC) announced the full production commencement of China's first deepwater oilfield secondary development project—the Liuhua 11-1/4-1 Oilfield Secondary Development Project. Since the first development well began operation, the oilfield has cumulatively produced over 900,000 tonnes of crude oil.

The Liuhua 11-1/4-1 Oilfield Secondary Development Project is located in the Pearl River Mouth Basin of China. It comprises the Liuhua 11-1 and Liuhua 4-1 oilfields, with a total of 32 production wells designed. The main production facilities include one deepwater jacket platform named "Hai Ji Er Hao," one cylindrical FPSO (Floating Production Storage and Offloading unit) named "Hai Kui Yi Hao," and one subsea production system.

"Hai Ji Er Hao" jacket platform

"Hai Kui Yi Hao" FPSO

As of now, all 32 production wells of this project have been fully put into production. The daily crude oil production has steadily increased to 3,900 tonnes, setting a new production record.

Reef limestone oilfields are among the most challenging reservoir types to develop. Their internal reservoir structure is highly complex, comprising cavities of varying sizes, sponge-like pores, and intricate networks of fractures. These reservoirs often sit atop massive "water cushions," meaning that once extraction begins, the underlying water can rapidly advance through the most permeable channels, causing uncontrolled water breakthrough. This often leads to wells being quickly flooded, leaving significant amounts of crude oil difficult to recover.

The Liuhua 11-1 oilfield is China's first deepwater oilfield and remains the largest proven reef limestone oilfield offshore China to date. Since its initial production in 1996, it has cumulatively produced over 20 million tonnes of crude oil. However, an estimated 140 million tonnes of crude oil reserves still remain trapped deep within the submarine formations.

During the initial development phase of the Liuhua 11-1 oilfield, the water cut of most production wells increased significantly within a year of operation. Controlling water production, stabilizing oil output, and enhancing oil recovery thus became critical to the efficient development of the field. After a decade of focused research and development on enhanced oil recovery technologies for reef limestone oilfields, China National Offshore Oil Corporation (CNOOC) initiated a comprehensive adjustment project for the secondary development of the oilfield.

Through precise control of oil column height, scientific avoidance of hidden faults, and systematic improvement in water control effectiveness, researchers have innovatively introduced multiple new extraction technologies and construction methods. They have explored and established a comprehensive oil-stabilization and water-control technology system tailored to offshore geological conditions. This has effectively enhanced both the crude oil recovery rate and extraction efficiency of the reef limestone oilfield, extending the operational life of this offshore field by 30 years.

Production data over the past year show that the comprehensive water cut of production wells in the Liuhua oilfield secondary development project is significantly lower than designed.

In this landmark project, our company's hydrocyclone, leveraging its advanced separation technology, has been successfully deployed in this critical undertaking. Its exceptional performance and reliability have provided robust support for the project's smooth operation.

Hydrocyclones are commonly used oil-water separation equipment in oilfields. By generating strong centrifugal force through pressure drop, the device creates a high-speed vortex effect inside the cyclone tube. Due to the difference in fluid densities, lighter oil particles are forced toward the center, while heavier components are pushed toward the inner.

The hydrocyclone adopts a pressure vessel design, incorporating specially engineered hydrocyclone tubes (MF-20 Model). It utilizes centrifugal force generated by a swirling vortex to separate free oil droplets from liquids such as produced water. This product features a compact size, simple structure, and easy operation, making it suitable for various operational scenarios. It can be used as a standalone unit or integrated with other equipment (such as flotation units, coalescing separators, degassing tanks, and ultra-fine solid separators) to form a complete produced water treatment and reinjection system. Key advantages include high throughput capacity per unit volume with a small footprint, high classification efficiency (up to 80%–98%), operational flexibility with turndown ratios of 1:100 or higher, low operational costs, and a long service life.

Proven in major global fields operated by CNOOC, CNPC, Petronas, and others across Southeast Asia, SAGA hydrocyclones are deployed on wellhead and production platforms. They provide reliable solids removal from gas, well fluids, and condensate, and are critical for seawater purification, production stream protection, and water injection/flooding programs.

Beyond hydrocyclones, SAGA offers a portfolio of acclaimed separation technologies. Our product line includes membrane systems for natural gas CO₂ removal, high-performance compact flotation units (CFUs), High quality Cyclone Desander and multi-chamber hydrocyclones, delivering comprehensive solutions for the industry's toughest challenges.