减少大型低温乙烯球罐预冷过程中VOC_(S)排放

REDUCE VOCS EMISSIONS DURIN G PRE-COOLING OF LARGE LOW-TEMPERATURE ETHYLENE STORAGE TANKS

对某石化企业乙烯罐区3000m^(3)低温乙烯球罐预冷过程的工艺操作进行了简要介绍,针对乙烯球罐需要预冷至-30℃以下才能接料投用的苛刻工艺条件及预冷操作的技术难题和安全环保风险,在理论分析可行的基础上,提出将预冷方式由“插底管进液”改为“顶部喷洒液滴”。实践证明,顶部喷洒液滴的预冷方式将球罐预冷时间由56h缩短至12h,减少了乙烯等挥发性有机物(VOC_(S))向火炬排放约30t,实现了碳减排和清洁生产目的。同时,也消除了因罐顶与罐底温差大导致球罐材质发生脆裂泄漏而引发的安全环保风险。

In view of the harsh process conditions of ethylene spherical tank that needs to be precooled to below-30℃before receiving materials and the safety and environmental protection risks of the pre-cooling operation,on the basis of theoretical analysis and feasibility,it is proposed to change the precooling method from“bottom tube inlet”to“top spraying droplets”in view of the harsh process conditions of ethylene spherical tank that need to be precooled to below-30℃before receiving materials and putting them into use.It has been proved in practice that the precooling method of spraying droplets on the top shortens the precooling time of the spherical tank from 56 hours to 12 hours,reduces the emission of volatile organic compounds(VOCs)such as ethylene to the flare by about 30 tons,and achieves the purpose of carbon emission reduction and cleaner production.At the same time,it also eliminates the safety and environmental protection risks caused by the brittle leakage of spherical tank material.caused by the large temperature difference between the top and bottom of the tank.