The key aspects of a caustic treating system pertain to the degree of contact between
the caustic and hydrocarbon to facilitate the mass transfer. Increasing the specific
surface area of contact in a two phase system necessarily creates a tight emulsion.
The product hydrocarbon often contains entrained caustic, which is not easily recovered
by a simple water wash followed by a separator drum. The spent caustic is often
regenerated with sour-naphtha stream that is used to extract the disulfide oils
into the hydrocarbon phase. The regenerated caustic often carries sour naphtha with
it, and the sour naphtha carries caustic with the disulfide oils to the hydrotreater
where the caustic will form a crust and reduce reactor life.
- Reduce caustic carryover from the Caustic Treater
- Reduce caustic carryover in the treated hydrocarbon stream
- Reduce caustic carryover in the naphtha used for regeneration
- Reduce hydrocarbon and disulfide oil carryover in the regenerated caustic