In-Situ Burning - One Method of Effective Oil Spill Response in the South China Sea

Abstract

Abstract Phillips Petroleum International Corporation Asia (PPICA) is the operator of the twin Xijiang Oilfields in the South China Sea. The very special characteristics of the Xijiang crude demanded that innovative means of cleanup be employed in the event of a major oil spill. The Xijiang crude has a very high wax content and high pour point. The crude must be heated to flow. In the event of a major oil spill, clean up would require non-traditional means of response. During the laboratory analysis it was discovered that if a specific thickness of crude could be contained on the surface of the water that it could be ignited and burned. The potential effectiveness of the burn was ascertained to be 95-98%. A decision was made in 1992 during the design engineering phase to utilize in-situ burning as the primary means of response in the event of a major oil spill. During April 1995 the first ever demonstration of in-situ burning was conducted in Shekou, Shenzhen, People's Republic of China by Phillips Petroleum International Corporation Asia. This exercise clearly demonstrated the effectiveness of in-situ burning on the Xijiang crude. Introduction Phillips Petroleum International Corporation Asia (PPICA) along with its co-venturers the China National Offshore Oil Corporation (CNOOC)and Pecten Orient Company have worked as an integrated team in the development of the Xijiang Oilfields in the Pearl River Mouth Basin of the South China Sea. PPICA is the operator of the twin Xijiang Oilfields. Environmental stewardship is a primary objective in all Company operations. The very special characteristics of the Xijiang crude demanded that innovative means of cleanup be employed in the event of a major oil spill. The Xijiang crude has a very high wax content and high pour point. The crude must be heated to flow. In the event of a major oil spill, clean up would require non-traditional means of response. As a result of laboratory testing it was determined that the Xijiang crude would turn into "globules" if a spill occurred. These "globules" would float. However, dispersants were ineffective on the crude and traditional containment and skimming operations were not effective. During the laboratory analysis it was discovered that if a specific thickness of crude could be contained on the surface of the water that it could be ignited and burned. The potential effectiveness of the burn was ascertained to be 95-98%. A decision was made in 1992 during the design engineering phase to utilize in-situ burning as the primary means of response in the event of a major oil spill. The use of in-situ burning is new to Asia. The special high temperature, ceramic fiber composite containment boom used by PPICA is new technology to the Asian offshore industry. During April 1995 the first ever demonstration of in-situ burning was conducted in Shekou, Shenzhen of the People's Republic of China by Phillips Petroleum International Corporation Asia. This exercise clearly demonstrated the effectiveness of in-situ burning on the Xijiang crude. Xijiang Production The two Xijiang Oilfields are currently producing in excess of 100,000 BOPD The two Xijiang platform wells are equipped with ESP's (electric submersible pumps). First stage of separation occurs on the platform with the production stream being pumped into 10 inch insulated pipelines from each platform through a PLEM (pipeline end manifold) up through the BTM (buoy turret mooring) system via flexible risers to the second stage separation processing system on the Nanhai Kai Tuo FPSO (floating production storage offloading) vessel. The FPSO is a 150,000 dwt (deadweight ton) one million barrel capacity vessel. P. 113