China Completes Its Longest Deepwater Oil Pipeline

China has completed installing its longest deepwater pipeline for oil and gas in a project led by China National Offshore Oil Corporation (CNOOC) Ltd, achieving a breakthrough in the country’s construction capacity for deepwater technology, according to a report from the China Global Television Network (CGTN).

The submarine pipeline is a crucial component of the phase 2 project of China’s first independently developed ultra-deepwater energy station, Shenhai-1, or Deep Sea-1, which became operational in June 2021, according to the report. The maximum operating depth in the area is nearly 3,280.8 feet (1,000 meters). Submarine pipelines serve as a “lifeline” in ensuring the smooth transportation of offshore oil and gas, as oil and gas extracted from the field have “complex components” and are subjected to high temperatures and pressures. Conventional sea pipes are unable to meet the production requirements, the report said.

CNOOC’s phase 2 project started construction in November 2022 and is located approximately 80/78 miles (130 kilometers) from Sanya City in south China’s Hainan Province between the Yacheng 13-1 gas field and the Shenhai-1 energy station. Once operational, the phase II project is expected to increase the peak annual output of the Shenhai-1 gas field from 105.9 billion cubic feet (three billion cubic meters) to 158.9 cubic feet (4.5 billion cubic meters).

CNOOC’s development model for the project includes a subsea production system, a shallow water jacket processing platform, and a remote-control system for a deepwater semi-submersible platform, according to Wu Hualin, deputy manager at the Hainan branch of CNOOC. The company is using a combined approach of 70.8 miles (114 kilometers) of deepwater large-diameter seamless steel pipe and 0.9 miles (1.5 kilometers) of deepwater bimetallic composite pipe in the deepwater environment to establish the “aorta” connecting the phase 2 project for oil and gas transmission, the report said.

According to the report, China has laid over 5,592.3 miles (9,000 kilometers) of offshore oil and gas pipelines to date.

In February 2023, CNOOC said that Shenhai-1, the first deep-sea gas field fully operated by a Chinese company, had produced over 35.3 billion cubic feet (one billion cubic meters) of natural gas, with a daily output of 353 million cubic feet (10 million cubic meters).

Shenhai-1 features the world’s first 100,000-metric ton semi-submersible oil production and storage platform and supplies 105.9 billion cubic feet (three billion cubic meters) of gas to south China’s Guangdong Province, Hong Kong and Hainan Province yearly, according to an earlier CGTN report.

Earlier in the month, CNOOC had commissioned the country’s first offshore carbon capture and storage (CCS) project. The CCS project is an auxiliary of the Enping 15-1 oilfields development, located in the Pearl River Mouth Basin, and can store over 1.5 million tons of carbon dioxide.

CNOOC reached a record high net production of 624 million barrels of oil equivalent (MMboe) in 2022, according to the company website. Its net production target for 2023 is 650 MMBoe to 660 MMboe.

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