Study On Fast Pyrolysis Characteristics And Kinetics Of Inferior Heavy Oil

The world’s oil resources are becoming more and more scarce,and the tendency of poor quality is becoming more and more serious.The efficient conversion and utilization of residue has always been a research hotspot,but there are many problems in technology at home and abroad.Therefore,the research and development of new residue processing technology has become a key problem in dealing with low-quality heavy oil.In this study,the common field coupling technology of inferior heavy oil pyrolysis and coke gasification is proposed.By coupling the cracking section and gasification section of the reaction process,high-quality oil and gas can be obtained,coke generation can be effectively reduced and residue conversion can be improved.This study makes some basic research on the characteristics of the process.The main research contents and results of this paper are as follows.The pyrolysis characteristics of Liaohe atmospheric residue on FCC catalyst as heat carrier before and after deactivation were studied.The pyrolysis characteristics of Liaohe atmospheric residue on FCC catalyst before and after high temperature hydrothermal deactivation were studied by using a self-designed small fixed fluidized bed and changing the three operating variables of reaction temperature,catalyst-to-oil ratio and space velocity.The results show that when the reaction temperature is taken as the investigation variable,the gas and coke increase with the increase of temperature under the two catalysts,and the catalyst can produce higher liquid phase yield after deactivation,ranging from 78.97 to 81.06 wt%,but the yield of C₅～350℃fraction in the liquid phase product is about 7 wt%lower than that under FCC catalyst;When the catalyst-to-oil ratio is taken as the investigation variable,the gas and coke increase with the increase of the catalyst-to-oil ratio under the two catalysts.When the catalyst-to-oil ratio is low,the growth rate of coke is faster than that of gas.When the catalyst-to-oil ratio is larger and larger,the gap between the yield of light oil obtained with the deactivated catalyst as the carrier and that before deactivation is also larger and larger;When the space velocity is taken as the investigation variable,under the condition of FCC catalyst,the yield of gas and coke increases with the increase of space velocity.Under the condition of inactivated FCC catalyst,the yield of gas and coke decreases first and then increases.Study on pyrolysis characteristics of Liaohe atmospheric residue under hydrogen supply.The effect of hydrogen supply conditions on the fluidization heat conversion of residue was investigated and compared with the data without hydrogen supply.When the reaction temperature was taken as the variable,the product trend was basically the same as that before adding hydrogen donor.The yield of gas and coke decreased slightly,and the yield of C₅～350℃distillate increased;When the catalyst-to-oil ratio is the investigation variable,the yield of gas and coke increases with the increase of catalyst-to-oil ratio.Both gas and coke are reduced.In terms of gasoline yield,when the catalyst activity is high,the gasoline yield will be higher under the condition of hydrogen supply,and the gasoline yield will not be significantly improved under the condition of deactivating the catalyst.When the space velocity is the investigation variable,tetrahydronaphthalene only affects the pyrolysis of residue in the physical layer.The yields of gas and coke increase with the increase of space velocity.Under the condition of two catalysts as carriers,the yield of gas and coke decreased by about 0.5wt%.By analyzing the pyrolysis characteristics of Liaohe atmospheric residue,five lumped kinetic model were established.By simplifying the five lumped kinetic equation,the reaction rate constant,pre exponential factor and activation energy were solved,and the parameters of the reaction rate equation were predicted.