Removal of sulfate from MEG streams using calcium chloride
AssigneeCameron International Corporation
InventorBrian Edward Messenger
Life of this patent
Estimating the term…
Abstract
A MEG recovery process is described, in which a MEG stream is processed by performing a divalent treatment to reduce dissolved divalent cations in the portion of the stream; performing a sulfate treatment to reduce dissolved sulfate ions in the stream, the sulfate treatment comprising adding an underdose of one or more calcium halides, one or more lower calcium carboxylates, or a mixture thereof to a treatment stream; and precipitating calcium sulfate from the treatment stream; performing a solids removal treatment to reduce solids in the stream; and returning the treated stream, depleted in divalent cations, sulfate ions, and solids, to the MEG recovery process.
Claims21
A method comprising:
- separating a monoethylene glycol (MEG) rich stream into a first effluent and a second effluent, the first effluent comprising MEG;
- reducing dissolved divalent cations in the first effluent or a stream derived from the first effluent via a divalent treatment comprising adding alkalinity to the first effluent or the stream derived from the first effluent to yield a divalent-treated stream;
- precipitating dissolved sulfate ions from the divalent-treated stream or a stream derived from the divalent-treated stream to yield a sulfate-treated stream, wherein the dissolved sulfate ions are precipitated via a sulfate treatment comprising adding an underdose of one or more calcium halides, one or more lower calcium carboxylates, or a mixture thereof, to the divalent-treated stream or the stream derived from the divalent-treated stream;
- and
- routing the sulfate-treated stream or a stream derived from the sulfate-treated stream to a MEG vaporization unit.
Dependencies are inferred from the claim text.