Height of the conversion catalyst

Domestic manufacturers generally rely on empirical data when determining the amount of catalyst to be used. Initially, they fill it according to the requirements specified by the design institute; for imported catalysts, the filling requirements are provided by the foreign suppliers. There is a significant difference between the results of theoretical calculations and the actual amount of catalyst used. I remember doing such calculations when I first started working at the factory.

What does it mean that the theoretical calculation results differ significantly from the actual loading amount? Was it a miscalculation or intentional deception?

This post was last edited by That makes sense on 2012-1-8 at 22:56. If you want to ask Mr. Xiang Dehui from the catalyst factory of Nanhua Company, refer to Issue S2 of 1980 of the journal \"Sulfuric Acid Industry\", titled \"Discussion on the Process Design Calculations for Reactors in the Sulfur Dioxide Oxidation Industry – Analysis of the Optimal Conditions for the Catalytic Process of Sulfur Dioxide over Vanadium Catalysts\". The theoretical calculations are based on his equations; however, the kinetic equations and related parameters applicable to the use of such catalysts in industrial reactions may be \"distorted\" as a result. While deciding on a specific model of vanadium catalyst to use, it is also necessary to calculate an appropriate loading rate based on factors such as the dimensions of the vanadium catalyst, the raw materials used for acid production, the acid production process, the capacity of the plant, and the operating conditions. This allows for the determination of the total amount of vanadium catalyst required for that sulfuric acid production facility. There are certain differences among various sulfuric acid manufacturers and design firms when determining the loading quotas. The loading rate for vanadium catalysts in our country is generally set at 220–250 L/(tH2SO4·d). In cases where operating conditions are particularly harsh, or under special circumstances such as very high gas concentrations and extremely low oxygen-sulfur ratios, it is necessary to consider increasing this loading rate accordingly; in some highly specialized acid production facilities, the loading rate may even need to be increased several times. Foreign low-temperature catalysts and large-particle, low-resistance catalysts: 195 liters of catalyst are required to produce 1 ton of acid per day.

The loading factor merely reflects the amount of catalyst required to produce one ton of acid per day; although this parameter is not usually mentioned for imported catalysts, it can still be used to assess the general level of catalyst loading. Since there are many actual conditions associated with each set of equipment, such as the atmospheric pressure at the site, gas concentration, the inner diameter of the converter, and so on. Therefore, it is highly unscientific to use only the loading factor to roughly estimate the actual loading. If the inner diameter of the converter differs, for devices of the same size and under the same loading factor, the filling height will vary, which in turn results in different specific pressure drops and gas distributions in each section. The loading height of a catalyst should generally be above 60 cm; if it is too low, the low pressure drop and uneven gas distribution may affect the conversion rate. Therefore, the converter should ideally be designed to be slim and tall.