Research On The Internal Flow Characteristics Of Fixed Bed Methanation Reactor With Double Catalyst Layers And Analyze The Structural Strength

In the paper,we focus on a fixed bed methanation reactor of Topsoe process which includes three fixed bed methanation reactors. The methanation reaction mainly occurs in the first methanation reactor, therefore, the simulation study is based on the first methanation reactor.SNG methanation reactor internal field distributions were obtained by researching the fixed bed methanation reactor. A methanation reactor referred to herein means the first methanation reactor.First, for determining the simulation model, the ANSYS-CFX software was used in establishment of the methanation reactor fluid model. In order to validate the simulation model, the simulation results with the design values were compared. If the results comparison was less than 5%, that simulation model was suitable. After the physical model and the simulation model are determined, the vectorgraph of temperature distribution, velocity distribution and component distribution were extracted. On the one hand, the distribution of the various parameters in the bed could be clearly defined; On the other hand, the results were analyzed to make the defect of the bed layer clear, then, the measures were put forward for the existing problems.Secondly, aiming to solve the problem of the reactor, the bed structure was changed. The relationship between the structure of the bed and the yield of methane was obtained. It is further determined that the structure of the bed can be better for the distribution of the temperature and the yield of methane. Thirdly, the reactor inlet parameters were researched, the ranges of parameters were proposed when the other parameters were within the design parameters. These parameters include the inlet temperature, the inlet pressure and the space velocity.Finally, the temperature profile and the pressure profile alone with the inner wall were acquired. The matched curve was obtained by the way to match curve. It was loaded into the equipment of the methanation reactor to be analyzed by thermal analysis. The result of thermal analysis, adding the mechanical load, were transferred the reactor. The thermal-stress coupling analysis of the methane reactor was carried out to ensure the safe and stable operation of the reactor.