In order to ensure the safety production of offshore heavy oil thermal recovery platform and establish the mathematical model of thermal recovery blowoff diffusion of offshore platform, ANSYS Fluent software was used to simulate the gas diffusion in the process of steam huff and puff thermal recovery, quantify the impact of thermal recovery blowoff process on the platform, and provide guidance for platform general layout. Taking LvDa 21⁃2 oil field as an example, due to the increase of methane content in the later stage of blowout, the slow diffusion rate caused by the decrease of blowoff volume, blowoff was easy to accumulate in the steam boiler and other higher equipment, thus causing potential safety hazards. By optimizing parameters of cold vent system and equipment layout, the impact of blowout on safe operation was lowered to the utmost and platform area was cut down by 5.9%. The study could provide reference for safety design of offshore thermal discovery platform.

In order to more fully rational use of Oman crude oil, the comprehensive evaluation of its properties was carried out. The results show that the freezing point of crude oil is low, as lower than -35 ℃, 20 ℃ density of 0.866 0 g/cm3, API° 31.11, the sulfur content of 1.41%, belong to the sulfur intermediate base crude oil. lower than 360 ℃ fraction yield was 4456%, lower than 520 ℃ fraction total 67.03%. The crude oil, light oil yield, total is higher, metal nickel and vanadium content is higher. This article carries on the comprehensive evaluation and analysis on the nature of each fraction, and is suitable for processing scheme was put forward.