Regenerator operating pressures

The quantity of stripping vapor required depends upon the solution purity needed to achieve the required product gas purity, the stripping column height, the nature of the solution, the ratio of CO2/H2S in the rich amine solution, and the regenerator operating pressure. 

Figure 2>88. Effect of temperature on degree of stripping obtainable for monoetbanolamine sotuUons. Temperature increased for aqueous MEA solution by increasing regenerator operating pressure, Reheard HHood, 1941 19471...

Under normal operations, the existing differential pressure governor is switehed to manual and the double slide valve is wide open. This valve must be suffieiently opened so that, even in the event of an emergeney expander trip, the entire flue gas flow ean pass through the double slide valve without the regenerator diseharge pressure inereasing to nonpermissible levels. 

The software in the Turbolog DSP eontroller ineludes a eontrol algorithm ealled SHEDCON, whieh eontrols the regenerator differential pressure under all operating eonditions. This software was designed in 1984 speeifieally for ECC applieations and was improved for the refinery projeet deseribed here. 

If, however, the FCC unit should be operated at a different duty point, whether this is due to a different flue gas flowrate or a different regenerator pressure, the bypass valves would either open too wide or not wide enough. The result is fluetuation in the regenerator outlet pressure. 

The regenerator pressure fell by 28 mbar. This value was within the eontraetually agreed limits. Nevertheless, two further tests were performed with modified parameters. Five hours after beginning the optimization proeess, a test was performed in whieh the regenerator pressure dropped by just 8 mbar. This value is within the normal operating spread of the regenerator output pressure. 

Figures 9 and 10 illustrate changes in two dependent variables dynamic N2 adsorption capacities and CH4/N2 separation factors. Independent variables are column temperature, operating pressure, and time allowed for vacuum regeneration. This experimental series used a constant feed rate of 6.0 1/min over a time of 1.00 min into a 1" dia. x 24" long adsorber filled with 180g of zeolite. Column depressurization took place for 1.00 min. and this was followed by a variable length vacuum regeneration.

Gas Feed Rate Feed gas composition Adsorber Temperature Operating Pressure Adsorber Granule Size Column Regeneration... 

It is probable that catalysts of this type have also been used for the desulfurization of Diesel fuels and crude oils (36). Operating pressures of 50 atm. with 0.2 cbm H2/kg. of feed and throughput of 2 kg./(liter catalyst) (hr.) are reported with catalyst-regeneration cycles of up to 150 hr. Table XIII shows the reported results temperature and yield were not given. 

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