海上平台冷放空可燃气扩散积聚规律研究

RESEARCH ON THE DIFFUSION AND ACCUMULATION RULE OF COLD VENT COMBUSTIBLE GAS AT OFFSHORE PLATFORM

为研究海上平台冷放空可燃气体扩散分布规律,以某平台为对象建立数值仿真模型及气体扩散模型,模拟火炬冷放空可燃气体扩散积聚行为。结果表明:冷放空可燃气在来风作用下可扩散至钻台区域,对钻台区域构成威胁;风速较小时,可燃气主要向上部空间发展,风速5.1 m/s时,1.25%体积浓度的可燃气最大扩散距离为85.9 m,聚集在井架上方,发生燃爆后将造成井架顶部设备失效;风速越大,天然气受稀释作用越强,可燃气越容易消散;不同来风风向下,可燃气分布体积和扩散距离基本一致。

In order to research on the diffusion and distribution rule of cold vent flammable gas at offshore platform,this paper takes certain platform as research object to establish the numerical simulation model and gas diffusion model and simulate the diffusion and accumulation behaviors of cold vent flammable gas of flare. The simulation results indicate that cold vent gas may spread to drill floor area under the action of the wind,which is a threat to drill floor area; the gas mainly spreads to upward space under low wind speed; when the wind speed is 5. 1 m/s,combustible gas with 1. 25% volume concentration may spread to the maximum diffusion distance of 85. 9 m and concentrates on the derrick area. And this will directly result in derrick equipment failure when explosion occurs because of combustion; the higher the wind speed becomes,the stronger the combustible gas dilutes and the easier the combustible gas diffuses; with wind coming from different directions,the distribution volume and diffusion distance of combustible gas are basically the same.