Injection and production project of pilot test on steam huff-puff in oilfield LD27-2, Bohai Sea

Based on the domestic and foreign exploration experience of steam huff-puff technology, a research was carried out for comprehensive analysis in combination with field practices from several aspects such as geology-reservoir engineering scheme, injection and production scheme and surface(platform) scheme. As a result, reservoir development scheme and steam-injection parameters were determined; ground-miniaturized and skid-mounted steam generators were developed, as well as the supported seawater desalination system and high-purity nitrogen system; oil-tubing steam injection technology, tubing-casing annulus high-purity nitrogen injection technology, steam-injection technology with deoxidizer and shaft corrosion preventions were designed. Electric submersible pump(application temperature of 250℃) was first used for offshore heavy-oil thermal recovery artificial lift to monitor the temperatures and pressures of high-temperature wells. Heavy-oil pilot test was first performed in oilfield LD27-2, Bohai Sea, and obtained favorable pilot results, providing a basis for the next large-scale development of heavy oil fields in Bohai Sea.