Qu Longtao, a competent worker in the Shengli Oilfield, used to inject high-temperature steam underground, but with the operation of the carbon capture, utilization, and storage project, or CCUS project, he now injects carbon dioxide instead.

"Injecting high-temperature steam into underground is a common oil displacement technology. It can reduce the viscosity of crude and enhance oil recovery," Qu said, adding that now injecting carbon dioxide can also achieve the same effect.

Carbon dioxide has become a powerful tool for oil displacement in the Shengli Oilfield.

The Shengli Oilfield, a major producer of crude oil and natural gas in Dongying, East China's Shandong province is a practitioner of the China's megaton carbon capture project.

The project will play a key role in cutting carbon dioxide emissions by capturing carbon dioxide from production activities and then either reusing or storing it. It is expected to become the country's largest CCUS whole industry chain demonstration base.

The project can reduce carbon dioxide emissions by 1 million tons per year, which is equivalent to planting nearly 9 million trees. Besides, the project will help China to honor its pledge to peak carbon emissions by 2030 and achieve carbon neutrality by 2060.

"The use of carbon dioxide for oil extraction is the latest technology application in the field of 'carbon neutrality' in Shengli," said Yang Yong, director of the Exploration and Development Research Institute of Shengli Oilfield. The carbon dioxide can be stored underground by the underground mineralization, displacement and dissolution of carbon dioxide.

By October 2021, Shengli has injected 420,000 tons of carbon dioxide into its seven oilfields, of which 390,000 tons were stored, which was equivalent to the annual emissions of 250,000 cars.

The Sinopec Key Laboratory of Carbon Capture, Utilization and Storage was established at the Shengli Oilfield in July 2021.

The laboratory will build five professional laboratories for carbon capture, carbon capture engineering, oil displacement, storage and carbon footprint to create a whole chain CCUS technology innovation team.

The Shengli Oilfield has implemented new energy initiatives in each of its eight oil production management regions to encourage the widespread use of renewable energy sources such as wind and solar energy.

These projects include wind power, photovoltaic and wind power combinations, and photovoltaic, sewage waste heat, and carbon dioxide combinations. The projects will minimize carbon emissions by more than 200,000 tons per year once completed.

Since the 13th Five-Year Plan (2016-20), the Shengli Oilfield has built and put into operation 72 new energy projects, saving more than 40 million yuan ($6.31 million) in annual costs and lowering carbon emissions.

A carbon dioxide injection system at Lai-113 block in the Shengli Oilfield, Dongying [Photo/Iqilu News]

A worker injects carbon dioxide underground at Lai-113 block in Shengli Oilfield. [Photo/Iqilu News]