Abstract:

This paper compares and analyzes several existing VOCs(volatile organic compounds) waste gas treatment technologies in petrochemical industry, and introduces the industrial application of low-temperature heavy aromatics absorption-adsorption-catalytic oxidation process in aromatics storage tank and ship exhaust treatment technology in a petrochemical enterprise. The operating conditions of the exhaust gas treatment device are as follows: the liquid-gas ratio of low-temperature heavy aromatics absorption is 40～60 L/m³, the absorption temperature is 5～15 ℃, the operating pressure of the absorption tower and the adsorption tank is 0.18 MPa, the adsorption time is 30 min, the desorption pressure of the adsorption tank is-0.095 MPa, the mass fraction of total hydrocarbon of waste gas entering the catalytic oxidation reactor is 3～6 g/m³, the temperature of catalytic oxidation reaction is 350～410 ℃, and the reactor space velocity is 5 000～20 000 h^-1. After treatment, the mass fraction of total non-methane hydrocarbon in the purification gas at the treatment device is less than 10 mg/m³, and the concentration of benzene, toluene and xylene are all less than the minimum detection limit of the instrument. The pollutant emission concentration of the purified gas meets the requirements of environmental protection emission standards and the emission index of grade A enterprises.

Key words: aromatic hydrocarbon tank, ship-loading, exhaust, VOCs, low-temperature absorption, adsorption, catalytic oxidation

摘要：

对比分析了现有石化VOCs(挥发性有机物)废气治理方面的几种技术，介绍了低温重芳烃吸收-吸附-催化氧化工艺在某石化企业芳烃储罐及装船排气治理技术工业应用情况。废气治理装置的操作条件：低温重芳烃吸收液气比40～60 L/m³,吸收温度5～15℃,吸收塔和吸附罐操作压力0.18 MPa,吸附时间30 min,吸附罐解吸压力-0.095 MPa,废气进入催化氧化反应器的总烃的质量浓度为3 000～6 000 mg/m³,催化氧化反应温度350～410℃,反应器体积空速5 000～20 000 h^-1。治理装置的净化气中非甲烷总烃的质量浓度均小于10 mg/m³,苯、甲苯、二甲苯浓度小于仪器最低检出限。净化气污染物排放浓度满足环保排放标准和企业相关排放指标要求。

关键词: 芳烃储罐, 装船, 排气, VOCs, 低温吸收, 吸附, 催化氧化