An accurate and complete geometric model was constructed to simulate the combustion, flow and temperature environment in the radiant section of the steam cracking furnace. Simulation of flow and radiation status has u...An accurate and complete geometric model was constructed to simulate the combustion, flow and temperature environment in the radiant section of the steam cracking furnace. Simulation of flow and radiation status has utilized the standard k-ε model and P1 model. The finite-rate/eddy-dissipation (finite-rate/ED) combustion model and non-premixed combustion model were both used to simulate accurately the combustion and the operation status of the steam cracking furnace. Three different surfaces of the steam cracking furnace were obtained from the simulation, namely:the flue gas temperature field of the entrance surface in long flame burners, the central surface location of tubes, and the crossover section surface. Detailed information on the flue gas temperature and the mass concentration fraction of these different surfaces in the steam cracking furnace can also be obtained by the simulation. This paper analyzed and compared the simulation results with the two combustion models, estimated the operation status of the steam cracking furnace, and reported that the finite-rate/ED model is appropriate to simulate the steam cracking furnace by comparing key simulation data with actual test data. This work has also provided a theoretical basis for simulating and operating the steam cracking furnace.展开更多
A coupled system simulating both firebox and reactor is established to study the naphtha pyrolysis in an industrial tubular furnace.The firebox model is based on zone method including combustion,radiation,and convecti...A coupled system simulating both firebox and reactor is established to study the naphtha pyrolysis in an industrial tubular furnace.The firebox model is based on zone method including combustion,radiation,and convection to simulate heat transfer in the furnace.A two-dimensional recirculation model is proposed to estimate the flow field in furnace.The reactor model integrates the feedstock reconstruction model,an auto-generator of detail kinetic schemes,and the reactor simulation model to simulate the reaction process in the tubular coil.The coupled simulation result is compared with industrial process and shows agreement within short computation time.展开更多
The analysis on the feedstock pyrolysis characteristic and the impacts of process parameters on pyrolysis outcomes can assist in the designing,operating and optimizing pyrolysis processes.This work aims to utilize bot...The analysis on the feedstock pyrolysis characteristic and the impacts of process parameters on pyrolysis outcomes can assist in the designing,operating and optimizing pyrolysis processes.This work aims to utilize both experimental and modelling approaches to perform the analysis on three biomass feedstocks—wood sawdust,bamboo shred and Jatropha Curcas seed cake residue,and to provide insights for the design and operation of pyrolysis processes.For the experimental part,the study investigated the effect of heating rate,final pyrolysis temperature and sample size on pyrolysis using common thermal analysis techniques.For the modelling part,a transient mathematical model that integrates the feedstock characteristic from the experimental study was used to simulate the pyrolysis progress of selected biomass feedstock particles for reactor scenarios.The model composes of several sub-models that describe pyrolysis kinetic and heat flow,particle heat transfer,particle shrinking and reactor operation.With better understanding of the effects of process conditions and feedstock characteristics on pyrolysis through both experimental and modelling studies,this work discusses on the considerations of and interrelation between feedstock size,pyrolysis energy usage,processing time and product quality for the design and operation of pyrolysis processes.展开更多
The kinetics of complex reaction systems were studied on molecular level with the combined method of Monte Carlo simulation and Structural Oriented Lumping by focusing on deep catalytic cracking （DCC） process, the m...The kinetics of complex reaction systems were studied on molecular level with the combined method of Monte Carlo simulation and Structural Oriented Lumping by focusing on deep catalytic cracking （DCC） process, the model parameters were optimized by means of routine analytic data of a DCC unit. A model was established to transform the feedstock of the complex reaction systems such as DCC to 1000-10000 pseudo-molecules with the Monte Carlo simulation and every molecule was expressed by 19 attributes. The results of model simulation showed that these pseudo-molecules reflected the characteristics of feedstock very well and their average properties gave a good agreement with the plant data.展开更多
基金supported by the technology development fund of China Petroleum & Chemical Corporation (Sinopec 409045)
文摘An accurate and complete geometric model was constructed to simulate the combustion, flow and temperature environment in the radiant section of the steam cracking furnace. Simulation of flow and radiation status has utilized the standard k-ε model and P1 model. The finite-rate/eddy-dissipation (finite-rate/ED) combustion model and non-premixed combustion model were both used to simulate accurately the combustion and the operation status of the steam cracking furnace. Three different surfaces of the steam cracking furnace were obtained from the simulation, namely:the flue gas temperature field of the entrance surface in long flame burners, the central surface location of tubes, and the crossover section surface. Detailed information on the flue gas temperature and the mass concentration fraction of these different surfaces in the steam cracking furnace can also be obtained by the simulation. This paper analyzed and compared the simulation results with the two combustion models, estimated the operation status of the steam cracking furnace, and reported that the finite-rate/ED model is appropriate to simulate the steam cracking furnace by comparing key simulation data with actual test data. This work has also provided a theoretical basis for simulating and operating the steam cracking furnace.
基金Supported by the National Natural Science Foundation of China(U1462206)
文摘A coupled system simulating both firebox and reactor is established to study the naphtha pyrolysis in an industrial tubular furnace.The firebox model is based on zone method including combustion,radiation,and convection to simulate heat transfer in the furnace.A two-dimensional recirculation model is proposed to estimate the flow field in furnace.The reactor model integrates the feedstock reconstruction model,an auto-generator of detail kinetic schemes,and the reactor simulation model to simulate the reaction process in the tubular coil.The coupled simulation result is compared with industrial process and shows agreement within short computation time.
基金Supported by Hong Kong RGC research grant(613808,614307)Hong Kong PhD Fellowship Scheme for Oyedun Adetoyese Olajire(PF09-05997)the Global Power and Energy Company Limited
文摘The analysis on the feedstock pyrolysis characteristic and the impacts of process parameters on pyrolysis outcomes can assist in the designing,operating and optimizing pyrolysis processes.This work aims to utilize both experimental and modelling approaches to perform the analysis on three biomass feedstocks—wood sawdust,bamboo shred and Jatropha Curcas seed cake residue,and to provide insights for the design and operation of pyrolysis processes.For the experimental part,the study investigated the effect of heating rate,final pyrolysis temperature and sample size on pyrolysis using common thermal analysis techniques.For the modelling part,a transient mathematical model that integrates the feedstock characteristic from the experimental study was used to simulate the pyrolysis progress of selected biomass feedstock particles for reactor scenarios.The model composes of several sub-models that describe pyrolysis kinetic and heat flow,particle heat transfer,particle shrinking and reactor operation.With better understanding of the effects of process conditions and feedstock characteristics on pyrolysis through both experimental and modelling studies,this work discusses on the considerations of and interrelation between feedstock size,pyrolysis energy usage,processing time and product quality for the design and operation of pyrolysis processes.
基金supported by the National Natural Science Foundation of China(ID No. 20476030)
文摘The kinetics of complex reaction systems were studied on molecular level with the combined method of Monte Carlo simulation and Structural Oriented Lumping by focusing on deep catalytic cracking （DCC） process, the model parameters were optimized by means of routine analytic data of a DCC unit. A model was established to transform the feedstock of the complex reaction systems such as DCC to 1000-10000 pseudo-molecules with the Monte Carlo simulation and every molecule was expressed by 19 attributes. The results of model simulation showed that these pseudo-molecules reflected the characteristics of feedstock very well and their average properties gave a good agreement with the plant data.
