基于Fluent的煤焦油悬浮床加氢反应器数值模拟与温度控制研究OACSTPCD

The coal tar slurry bed hydrogenation reactor is the core equipment of coal tar slurry bed hydrogenation technology.However,a significant challenge in its practical application lies in the temperature surge observed in the upper and middle sections of the reactor.To address this issue,computational fluid dynamics and Fluent software were used to simulating tempera-ture variations within the hydrogenation reactor and investigates various temperature control strategies.The results show that the temperature within the coal tar slurry bed hydrogenation re-actor rapidly increases at a height of 3.0 m.After the implementation of a cold hydrogen tube at the specific location where the temperature surge occurs,the introduction of cold hydrogen not only effectively regulates the temperature in the upper part of the reactor,resolving the tempera-ture surge issue,but also led to a more uniform distribution of temperature both axially and ra-dially throughout the reactor.The suitable temperature range of cold hydrogen is 41℃-43℃,while the optimum temperature is 43℃.Furthermore,the alterations of the flow field within the reactor,both prior to and subsequent to the introduction of cold hydrogen were studied.Based on the simulation results of flow velocity patterns and the nephograms of temperature distribution,it can be inferred that without the introduction of cold hydrogen,local coking phenomenon occurs at the height of 3.5 m within the reactor.When the height reaches 5.0 m,local blockage caused by coking starts to appear in the reactor,and at a height of 5.5 m,serious blockages occur due to extensive coking.The introduction of 43℃ cold hydrogen not only resolves the temperature surge issues,but also inhibites the axial flow within the reactor,thereby promoting the radial flow and mixing of the reaction materials.This results in a more uniform distribution of velocity and gas holdup,which is beneficial to the mass transfer and coal tar hydrogenation within the re-actor.