Abstract:

In this paper, it is introduced volatile organic compounds(VOCs) calculation method about the crude oil external floating roof storage tanks. Taking the petroleum depot composed of 12 sets of 100 dam³ of crude oil external floating roof storage tanks with an annual turnover of 10 million tons as the research object, the influence of the VOCs emissions of the parameters such as different seal forms, shell clingage and deck fittings are compared and discussed, and the main influence factors are summarized and analyzed. The results show that the VOCs emission can be reduced by 70% after adding the secondary seal; The VOCs emission under the heavy rust condition is nearly 100 times that under the light rust condition; The VOCs emission of the deck fittings with seals can also be reduced by 36.5% compared with the deck fittings without seals; The withdrawal loss is the largest source of VOCs emission, through the comparative analysis of the two combined conditions. In combination with the current national management requirements and technical and economic conditions, the selection and management suggestions for reducing VOCs emissions of external floating roof storage tanks are put forward, such as primary high-efficiency sealing and secondary sealing, sealing of deck fittings, and increasing tank cleaning frequency.

Key words: external floating roof storage tanks, VOCs, emission, rim seal loss, withdrawal loss, deck fittings loss, pollution control requirements

摘要：

对原油外浮顶储罐的挥发性有机物(VOCs)计算方法进行了介绍。以由12台100 dam³外浮顶原油储罐组成，年周转量10 Mt的原油储备库为研究对象，对比介绍了储罐密封形式、储罐内壁状态及浮盘附件等对于VOCs排放量的影响，并对主要影响因素进行汇总分析。结果表明：增加二次密封VOCs排放量可减少70%;重锈工况下VOCs排放量是轻锈工况下的近100倍；有密封件的附件比不安装密封件的附件，VOCs排放量可减少36.5%;通过对比分析，发现挂壁损耗是VOCs排放量的最大来源。结合国家现行的管理要求及技术、经济条件，提出减少外浮顶储罐VOCs排放量应采取一次高效密封+二次密封、对浮盘附件进行密封、增加清罐频率等选型及管理建议。

关键词: 外浮顶储罐, VOCs, 排放量, 边缘密封损失, 挂壁损耗, 浮盘附件损耗, 污染控制要求