摘要：
随着世界范围内原油不断趋于重质化和劣质化,重油的高效加工利用成为关注的焦点,国内外学者研究表明,超声空化作用可以有效促进渣油的裂解.为进一步搞清超声作用对渣油物化学性质的影响以及沥青质裂化获得的焦炭形貌,在反应时间为2h、反应温度为400～440°C、超声波的功率为2000W、频率为20 kHz的条件下,对比研究了常压渣油在超声波热裂化与传统热裂化条件下反应得到的气体产物组成、液体收率、反应生焦率和焦炭的形貌分析结果.结果表明,加载超声波对于热裂化反应气体产物分布基本没有影响,其能够促进烷烃侧链断裂、环烷烃开环反应和稠环芳烃的裂解,使得液体收率有所升高.使用超声波代替搅拌釜中的搅拌杆,生焦率大幅降低,焦炭结构有显著变化:颗粒减小,由块状变为互相黏连的小球状,表面光滑,吸附物较少,层片排列更规则,分散性更好,同时超声波作用可以显著减少器壁结焦.%With world-wide heavier and poorer quality of crude oil,heavy oil processing and utilization of efficient processing of heavy oil has become a major challenge.A large number of scholars in China and abroad have shown that ultrasonic cavitation can effectively promote the cracking of residual oil.Thermal cracking reaction results of atmospheric residue were studied in order to realize the differences of ultrasonic thermal cracking and traditional thermal cracking.The gas product composition,liquid yield,coke yield and morphology analysis of the coke were compared.The reaction time was 2 h,the reaction temperature was 400-440°C,the ultrasonic power was 2000 W and the frequency was 20 kHz.The result showed that there was no difference between the compositions of gas products of the two reactions.Ultrasound can promote the cracking of alkane side chains,the ring-opening of naphthenes and the cleavage of PAHs,which leads to the increase of liquid yield.With the use of ultrasonic device instead of agitator stirring rod,the coke rate significantly reduced,coke structure has significant changes:reduced sizes for the particles,shape change from the block into a mutual adhesion of small spherical,smoother surface,less adsorbate,more regularly arranged layers,and better dispersion.The role of ultrasound could significantly reduce the wall coke.
