Xinjiang Oilfield Pioneered Domestic SAGD Underground Electric Heating Technology

Xinjiang Oilfield Pioneered Domestic SAGD Underground Electric Heating Technology

As of January 11, the FHW3120 well group in Chong18 well area of Fengcheng Oilfield, Xinjiang, after adopting SAGD downhole high-power electric heating start-up technology, the stage oil-vapor ratio has increased by 20 times, the energy consumption has decreased by 90%, and the input-output ratio has reached 1:2.6, marking a new breakthrough in "replacing steam with electricity" in heavy oil exploitation.

Heavy oil, also known as heavy oil, is also known as "immobile oil fields" and accounts for more than 70% of the world's oil reserves. Among them, super heavy oil is like condensed bitumen, which is a world-class problem. Fengcheng Oilfield is rich in super heavy oil reservoir resources, but the development of SAGD development technology has been plagued for a long time by the problems of high energy consumption and uneven horizontal section utilization. Since 2017, Xinjiang Oilfield has joined forces with petrochina Research Institute of Exploration and Development to form a research team led by Sun Xinge, chief technical expert of Xinjiang Oilfield, to research and develop SAGD downhole high-power electric heating start-up technology. In June 2023, the research team installed a high-power electric heater in the FHW3120 well group of Fengcheng Oilfield to carry out the start-up test of full-well balanced SAGD electric heating without pressure between Wells.

This well group is the first in China to use SAGD downhole high-power electric heating start-up technology to produce heavy oil. This technology is a kind of heavy oil in situ electric heating mining technology. Heavy oil in-situ electric heating mining technology is an organic combination of heavy oil development and new energy green electricity application, ensuring stable production and increase of heavy oil at the same time, greatly reducing carbon dioxide emissions, is a green, low-carbon and efficient exploitation of heavy oil new technology. He Wanjun, a member of the SAGD underground high-power electric heating start-up technology research team of Xinjiang Oilfield, introduced that this technology uses the SAGD method of double horizontal Wells, parallel deployment of a pair of steam injection Wells and production Wells at the bottom of the reservoir, and the horizontal section of the two Wells are placed with high-power electric heaters, through the underground electric heating method, so that the crude oil can flow smoothly between the two Wells. It has the characteristics of low cost and high recovery rate.

As of January 11, a total of 2,150 tons of heavy oil had been produced in four rounds of tests. Compared with the traditional SAGD technology, SAGD downhole high-power electric heating start-up technology can shorten the preheating time by 40%, reduce carbon emissions by 95%, save 36,000 tons of steam and more than 2.4 million cubic meters of natural gas per well group, and save about 150,000 yuan of sewage treatment costs. More importantly, this technology takes advantage of the intermittent heating characteristics of heavy oil development, so that the electricity generated by wind and solar energy can be absorbed on the spot.