Steam assisted gravity drainage (SAGD) is a thermal oil recovery technology that uses gravity to drive the flow of crude oil by injecting steam into the reservoir to heat heavy oil. The typical application method is to drill two parallel horizontal wells inside the oil reservoir. Usually, a horizontal production well is drilled at the bottom of the oil reservoir, and a horizontal steam injection well is arranged in parallel above, which is combined with the use of Highland Company’s Rotaflex pumping unit to form an injection production well group.
Since 2006, the Liaohe Oilfield has carried out SAGD pilot tests, which have achieved a recovery rate of 60% for ultra heavy oil through the theory of flooding and release composite development and dynamic control technology. 18 SAGD 100 ton wells have been cultivated, among which the Du 84 Guanping H61 well has achieved a daily oil production of 110 tons for 17 consecutive days, with a cumulative oil production of 1287300 tons [2] [12]. In 2024, Xinjiang Oilfield will adopt downhole high-power electric heating start-up technology in the FHW3120 well group, reducing preheating time by 40%, reducing carbon emissions by 95%, and saving 36000 tons of steam and over 2.4 million cubic meters of natural gas. In 2025, the Fengcheng Oilfield in Xinjiang will launch the world’s first tower type solar thermal replacement project for ultra heavy oil extraction. Through 23700 solar mirrors, the project will achieve a solar thermal conversion efficiency of 53%, supply 52000 tons of steam annually, replace 3.92 million cubic meters of natural gas, and reduce carbon emissions by 8500 tons.
The first well group in China to use underground high-power electric heating SAGD start-up technology (i.e. in-situ electric heating for heavy oil production technology, hereinafter referred to as “electric heating SAGD preheating technology”) to extract heavy oil – the FHW3120 well group in the Heavy 18 well area of Fengcheng Oilfield has already extracted 2220 tons of heavy oil. As the first production well in China to use electric heating SAGD preheating technology for SAGD oil recovery in dual horizontal wells, in June 2023, technicians installed high-power electric heaters in the steam injection well and production well of the well group, and used electricity instead of steam to extract heavy oil. After six months, the well group saved 15000 tons of steam and millions of cubic meters of natural gas.
By utilizing this technology, Xinjiang Oilfield Company has built the largest industrial production base for SAGD dual horizontal wells in China, and this technology has become the main development technology for the stable production of 4 million tons of heavy oil in Xinjiang. At the same time, SAGD technology from Xinjiang Oilfield Company has also gone abroad to serve ultra heavy oil and oil sands projects in North America.
