Page 293 - Petroleum and Gas Field Processing

Figure 11 Sulfinol process.

absorber. Part of the cooling may be by heat exchange with the rich
solvent for partial recovery of heat energy. In some applications where
there is a large amount of hydrogen sulfide in the feed, the overall
Sulfinol/Claus plant has a balance that permits the omission of the heat
exchanger. The gas flashed from the rich solvent after partial depressuring
is shown in Figure 11 as fuel gas. In some cases, it is desirable to treat this
gas stream with Sulfinol solvent to control the acid gas content of the
plant fuel supply.
The Sulfinol solvent reclaimer is used in a small ancillary facility for
recovering solvent components from higher boiling products of
alkanolamine degradation or from other high-boiling or solid impurities.
A Sulfinol reclaimer is similar to a conventional MEA reclaimer, but it is
much smaller than that in an MEA plant of comparable gas treating
capacity. Usually, the Sulfinol reclaimer need not be started up until
several months after the treating plant is started up.

Comparison of Physical Solvents
Purisol has the highest capacity for absorption of acid gases and it is the
most selective; however, it is the most volatile. Selexol is more selective
than Fluor solvent, but it dissolves propane. All solvents exhibit significant
affinity for heavy paraffins, aromatics, and water. Water absorption make
them good dessicants.
The loading capacity of physical solvent is much higher than amines.
If we consider Figure 12, we see that at a partial pressure of H 2 Sof

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