Breakthrough in underground high-power electric heating steam generation technology in Liaohe Oilfield, China

The 3-megawatt downhole high-power electric heating steam generator independently developed by PetroChina Liaohe Oilfield completed a 33 day continuous test in the Du84 Xing H106 well, producing saturated steam with a dryness of over 70%, marking a key step in the engineering application of 3-megawatt downhole high-power electric heating steam generation technology.

This technology has promoted the breakthrough of steam production replacing gas with electricity, opened up a new path for green transformation in heavy oil development, and can also assist in the development of shale oil, coalbed methane, and deep and ultra deep heavy oil SAGD (steam assisted gravity drainage technology).

In the past, heavy oil thermal recovery relied on surface boilers to burn natural gas to generate steam. This technology achieved a breakthrough of 'above ground water injection and underground steam production' through a 3-megawatt underground high-power electric heating steam generator, eliminating heat loss along the way, not only improving the dryness of underground steam and development efficiency, but also reducing natural gas consumption, "said Zhang Fuxing, an enterprise technical expert at the Liaohe Oilfield Oil Production Technology Research Institute of China Petroleum.

For a long time, Liaohe Oilfield has been committed to tackling green and low-carbon development technologies for heavy oil. After developing 400 kW and 1 MW underground high-power electric heating technologies, it has also successfully developed a 3 MW underground high-power electric heating steam generation technology. During 33 days of continuous operation, the device withstood pressure tests ranging from 2 megapascals to 7 megapascals, fully verifying the feasibility of the structure and principle of the electric heating steam generation system. The project research team has successfully overcome the challenges of extreme prefabrication technology for steam generators in small underground spaces, insufficient power density in existing processes, and formed processes such as high-power density efficient heat exchange, continuous well entry, heavy-duty suspension, multi-channel sealed well construction, as well as key technologies such as underground monitoring, water injection, and power supply joint steady-state control. Eight invention patents have been applied for.