不同补氮程度油品罐通过呼吸阀排放油气危险性研究

Study on the hazard of oil and gas emissions from oils tank with different nitrogen supplement levels through breathing valves

在大型油品贮罐建设量增加的趋势下,针对内浮顶罐在不同补氮程度下形成的不同浓度的气相空间油气,通过呼吸阀排放时形成的爆炸性危险的研究尚显不足。采用Fluent模拟研究不同补氮程度下形成的气相空间油气,在不同风速下通过呼吸阀排放时的爆炸危险性。结果表明,在罐底安装针对呼吸阀排放危险性的监测设备无法进行有效监测;外界风速在罐顶形成旋涡,在呼吸阀附近挤压作用明显,对呼吸阀排放出的油气起到加速扩散和稀释作用;在有无外界风干扰时,距离罐顶中心0.1 m处安装监测设备,均可以快速监测到气相空间内浓度为5%~100%的油气经过呼吸阀排放的爆炸危险性;罐内、外监测设备监测到危险性浓度后,应采取预防气相空间内形成危险性油气浓度、预防气相空间内形成可排放压力、防止危险性浓度的油气排放等措施,以进行综合治理。

With the increasing construction volume of large oil storage tanks,there is still insufficient research on the explosive hazards caused by the gas phase oil and gas concentration formed by internal floating roof tanks under different nitrogen replenishment levels and the discharge through breathing valves.The oil and gas concentration in the gas-phase space formed under different nitrogen supplementation levels was studied using Fluent simulation,and the explosion hazard of breathing valve emissions at different wind speeds was studied.The results show that installing monitoring equipment for breathing valve emissions at the bottom of the tank cannot effectively monitor the hazard;The external wind speed forms a vortex at the roof of the tank,and the squeezing effect is obvious near the breathing valve,which accelerates the diffusion and dilution of the oil and gas discharged from the breathing valve;When there is no external wind interference,the monitoring equipment can be installed 0.1 m away from the center of the tank roof to quickly monitor the explosion hazard of oil and gas concentration of 5%~100%in the gas phase space discharged through the breathing valve;After the monitoring equipment outside and inside the tank detects hazardous concentrations,comprehensive measures should be taken to prevent the formation of hazardous oil and gas concentrations in the gasphase space,prevent the formation of discharge pressure in the gas-phase space,and prevent the discharge of oil and gas of hazardous concentrations.