Numerical Study of the Effect of Furnace Geometry on the Catalyst Tube Lifetime of a Steam Methane Reformer

The catalyst tube lifetime of a practical steam methane reformer is analyzed numerically in this paper. The effect of reformer geometry on the flow development, chemical reaction, and catalyst tube lifetime is discussed. The results of this study reveal that the catalyst tubes in the downstream areas of the reformer have longer lifetimes while those in the upstream areas have shorter lifetimes. In most areas of the reformer, as the shifted height of the reformer roof increases, the temperatures and pressures reduce while the catalyst tube lifetime increases. However, near the sidewalls, as the shifted height of the reformer roof increases, the temperatures and pressures may increase while the catalyst tube lifetime may reduce. Nevertheless, from an overall view, raising the reformer roof reduces the temperatures and pressures and increases the catalyst tube lifetime. Finally, the shift of the reformer roof has a minor effect on the hydrogen yields at the catalyst tube outlets, although a careful observation reveals a similar trend to the temperature distributions.