The length of time between regenerations is approximately 1.76 years.
To calculate the length of time between regenerations in a reformer operating under the given conditions, several parameters and factors need consideration. The Liquid Hourly Space Velocity (LHSV) is a crucial parameter representing the flow rate of liquid feed per hour per unit volume of catalyst. In this case, LHSV is given as 3.0 v/hr/v.
The feed rate, specified as 5000 barrels per stream day (BPSD), is essential in understanding the volume of feed processed. The feed gravity, indicated as 55.0° API, provides information about the density of the feedstock.
The catalyst bulk density, denoted as 50 lb/ft³ (802 kg/m³), is the mass of catalyst per unit volume. Additionally, the hydrogen-to-feed ratio of 8000 scf/bbl (1424 Nm³/m³) influences the overall reaction dynamics. The deactivation criterion specifies that the catalyst deactivates after processing 90 barrels of feed per pound of catalyst. Considering the catalyst bed's depth of 6 ft in each of the three reactors, the total volume of catalyst can be determined.
To calculate the time between regenerations, the total volume of processed feed per unit time is divided by the volume of catalyst deactivated per unit time. This calculation involves converting units appropriately and considering the number of reactors. The resulting time, approximately 1.76 years, represents the duration between regeneration cycles, ensuring the catalyst's optimal performance in the reformer under the specified operational conditions.