5T kL fL JLT dTj i 5q J

dz i>cvt[r dr dr2J Pcvz

T ; temperature z ; length along axis k ; heat conductivity

P ; density of gas c ; specific heat at constant pressure

By solving this differential equation, temperature distribution is calculated.

Figure 3 shows the results of the simulation of temperature and CO concentration distributions. The vertical axis shows the direction of gas flow. The horizontal axis shows the radius of the reactor. At the entry section of the reactor, temperature rises by the reaction heat and thereafter temperature decreases gradually by cooling. Temperature at center is highest as regards distribution of radius direction. On the other hand temperature near cooling coil are low. The CO concentration decreases greatly at the entry section and thereafter decreases slowly.

To verify the simulation, detailed data were obtained from actual plants. Figure 4 shows the result of simulation and a part of detailed data from an actual plant. The temperature profile of simulation almost coincides with the actual data. The CO concentration at the outlet of the actual plant was 0.90%, and was nearly equal to the calculated value obtained 0.95%. Hence, it is proved that the calculated result by simulation agreed with the actual data, and that the performance of CO shift process can be predicted by using this reactor simulation.

Since sintering level at the targetted operation hours could be evaluated, it is now possible to evaluate the process performance by making simulation calculation using the reaction rate constant of the catalyst at that sintering level.

I Cell

Temperature CC)

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