Simulation And Analysis: Oxidative Dehydrogenation Of Propane To Propene

Petroleum resources are increasingly depleted,and the proportion of non-petroleum-based propene production routes is expected to gradually increase.Oxidative dehydrogenation of propane can reduce unit energy consumption by 45% compared to direct dehydrogenation.The unit has been put into production overseas,but there is no industrial application in China due to technological monopoly.Therefore,the research on the oxidative dehydrogenation of propane has important economic and social benefits.Existing research based on thermodynamics believes that the addition of water vapor or oxygen to the reaction system is not conducive to improving the reaction conversion rate,but is contrary to the phenomenon of engineering practice.Therefore,it is necessary to further simulate the analysis and reasonably optimize the reaction conditions so that the oxidative dehydrogenation conversion of propane reaches a better level.In this paper,R1 fixed-bed reactor and R2 oxidative dehydrogenation reactor models are established respectively.In the dimensions of reaction thermodynamics,kinetics,catalyst,and reactor,etc.,factors such as reactor structure,operating conditions,bed and catalyst parameters are analyzed.The effects of propane conversion,propene selectivity and degree of mixing were proposed,and an optimal design scheme was proposed.In the reaction thermodynamics analysis part,the Aspen software is used to establish a Gibbs reactor model,which confirms the experimental results of adding water vapor or oxygen to reduce the propene yield in the reaction system;the simulation analysis part of the reaction process combines existing experimental data and kinetic equation,establish a steady-state tandem reactor model,obtain a reference group that is consistent with industrial installations(propene yield 44.9%),and analyze the equipment conditions of reactor length and diameter,and temperature,pressure,space-time,water vapor,and The influence of operating conditions such as oxygen flow rate on propene yield,and appropriate amounts of oxygen and water vapor are helpful to improve yield.Optimization of parameters such as space-time,water vapor,and oxygen flow rates increased the propene yield to 52.0%,48.5%,and 45.0%,respectively.The multi-field simulation part of the reactor uses Comsol software to couple the velocity field,the concentration field and the temperature field.The reactor structure is innovatively designed,and the reaction-transfer model of the R1 reactor bed and catalyst particles is established,and the R2 reactor Oxygen mixing model.In the R1 reactor,increasing the catalyst porosity,reducing the equivalent particle size,and reducing the particle temperature are conducive to increasing the effective factor of internal diffusion.The inlet propane feed volume or bed porosity increases,and the conversion rate decreases.The external diffusion effect has a limited degree of influence on the reaction;in the R2 reactor,through qualitative and quantitative analysis,conditions such as the radius and number of oxygen gas inlet devices,as well as the speed and concentration of the gas inlet,affect the rapid gas-gas mixing efficiency,which in turn affects the actual conversion of the reaction.Within a certain range,the smaller the diameter and the larger the number of nozzles,the higher the mixing effect and the degree of conversion.