Modeling,simulation And Optimization Of Thermal Cracking Reactor

Myrcene is an important chemical products and raw materials in the fine chemicals and pharmaceutical chemicals,which is obtained mainly by β-pinene thermal cracking(thermal isomerization)in industry at present.In the current work,modeling,simulation and optimization analysis for the core equipment of the process of β-pinene thermal cracking were carried out,and the control systems integration scheme of the high temperature thermal cracking tubular reactor was proposed.The results of this study could provide reference for process control and optimizing the operating conditions of the actual technology.The primary research contents are as follows:(1)A comprehensive summary and review was introduced which contains the common methods and typical applications of the process simulation,the application and progress of simulation technology of pyrolysis process,commonly methods of process modeling as well.It was referred to established technical route and method for this paper.(2)The reaction mechanism of production of myrcene by β-pinene pyrolysis was analyzed systematically.According to the thermal reaction network and mechanism proposed by A.Stolle,some reasonable hypotheses were presented and the steady-state mathematic model of thermal cracking reaction process was established on the basis of heat balance and mass balance calculation.In order to reduce the difficulty of parameter estimation,the activation energy of each reaction was fixed and four pre-exponential factors were gained by using SQP algorithm and Gear algorithm combined with data collected from industry field.Subsequently,the model was verified,by which the mean relative error and the average absolute error between model predicted value and measured value are 0.367%and 0.279 respectively.Results showed the constructed mathematic model has a good predict ability,so it could be used in industrial off-line analysis(3)Simulation of the distribution of the main product(myrcene)and the reaction temperature profile in the axis of the tubular reactor were performed by the developed mathematic model in detail.Then the impact of changing the feed flow rate and heating temperature outside reactor on the myrcene concentration was analyzed.At last,some heating projects were proposed for thermal cracking tubular reactor under the condiction of same average temperatures.And the three-stage heating program was preferably selected to heat the tubular reactor by comparing the myrcene concentration of reactor outlet(4)System integration and design of automatic control scheme for producing myrcene were proceeded.In which the process control schemes were designed and equipments were selected for the production of myrcene according the results of process simulation.A platform for process controlling and data acquiring in form of IPC+PLC was constructed which established a good foundation for process controlling and optimization in later.