水力空化改质对减压渣油性质的影响

Effects of Hydrodynamic Cavitation Upgrading on the Properties of Vacuum Residue

利用水力空化过程产生局部的高温、高压、高射流以及强大的剪切力等极端化学物理条件改质处理减压渣油,改质处理后减压渣油的密度、黏度、残炭等理化性能均得到改善。通过APPI FT-IR、沥青质粒径分布技术和多重光散射技术进一步研究了减压渣油水力空化改质机理。结果表明:水力空化改质后减压渣油相对分子质量分布、芳烃类化合物缔合作用变小;沥青质对低DBE化合物吸附性能降低,沥青质分子相互团聚作用力减弱;沥青质胶束粒度分布降低,当水力空化压力为8 MPa、处理1次时,减压渣油改质效果最佳,其20℃时密度、40℃时黏度、残炭、沥青质质量分数分别由0.9802 g/cm^(3)、660.5 mm^(2)/s、15.31%、3.3%降低至0.9711 g/cm^(3)、569.4 mm^(2)/s、14.76%、2.6%;经过水力空化处理后,减压渣油延迟焦化的焦炭产率降低2.12百分点,液体产率和气体产率分别增加1.86和0.26百分点。

The hydrodynamic cavitation process could produce extreme physical conditions such as local high temperature,high pressure,high jet flow and strong shear force.A hydrodynamic cavitation device was proposed to treat the vacuum residue(VR).The effects of hydrodynamic cavitation pressure and treatment times on the properties of the vacuum residue were investigated.APPI FT-IR MS and DLS were used to analyze the molecular composition and asphaltene aggregates particle size distribution,respectively,to understand the effects of upgrading by hydrodynamic cavitation from the perspective of asphaltene structural characteristics.The results show that the molecular weight distribution of VR and the force of the self-associated in aromatic hydrocarbons class species became smaller;aromatic hydrocarbons class species in asphaltene has lower adsorption performance for low double bonds equivalent compounds;agglomeration force of asphaltene molecules is weakened;particle size distribution of asphaltene aggregates is reduced.The effect of the cavitation pressure of 8 MPa is the best when treated for 1 time.The density,viscosity,residual carbon and asphaltene mass fraction of the vacuum residue are reduced from 0.9802 g/cm^(3),660.5 mm^(2)/s,15.31%and 3.3%to 0.9711 g/cm^(3),569.4 mm^(2)/s,14.76%and 2.6%,respectively.At the same time,the delayed coking property of vacuum residue was also investigated.The results show that the coke yield is decreased by 2.12 percentage points,the yields of liquid and gas are increased by 1.86 percentage points and 0.26 percentage points,respectively.