Abstract: 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.

Key words: Offshore platform, Thermal recovery, Blowout, Cold vent, Numerical simulation

摘要： 为确保海洋稠油热采平台的安全生产，建立海上平台热采放喷气扩散数学模型，利用ANSYS Fluent软件对蒸汽吞吐热力开采过程中气体的扩散进行模拟计算，量化热采放喷过程对平台的影响，从而指导平台设备设施总体布置。以旅大21⁃2油田为例进行分析，由于放喷后期甲烷含量升高，且放喷气量减小造成扩散速度慢，放喷气容易在蒸汽锅炉等较高的设备间富集造成安全隐患。通过优化放空系统参数和设备布置方案，最大限度降低了热采放喷和冷放空对安全操作的影响，并减小平台面积5.9%。建立的模型考虑了平台主要设备结构、气体组分、风速、湍流脉动等因素的影响，满足工程精度要求，研究结果为热采平台的安全设计提供可靠依据。

关键词: 海上平台, 　热采, 　放喷, 　冷防空, 　数值模拟