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Green Oilfield in Bohai Bay

Chenghai Block at Dagang Oilfield is located in Huanghua Shoals of the Bohai Bay. To minimize the environmental impact caused by drilling and oil production on the surrounding waters, three artificial islands were built. Economic and intensive use of land is realized by an “onshore production of offshore oil” approach that uses wellhead-slot batch drilling, cluster well drilling with a modular rig, and extended-reach horizontal well drilling and waterflood. Meanwhile, all wells are equipped with safety valves and automatic protection devices, as well as offshore firefighting equipment and an oil spill emergency response system, to ensure safe drilling and production.

The artificial islands feature well-designed oil pollution treatment facilities and sewage treatment systems operating in a closed-loop. Wellhead-slot wastewater and summer rainwater are collected and recycled. Reusable drilling fluid is used in place of oil-based mud and concrete pits are available to contain workover wastes. All industrial and domestic waste is collected for centralized processing. Since becoming operational in 2007, offshore oil production has been carried out in a green way, and has been free of any man-made environmental accidents.