Reducing slurry emulsion and foaming in oxidation-reduction sulfur removal processes
A surfactant composition in aqueous phase includes 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate. The non-ionic alkyl ethoxylate is a fast wetting agent. The block copolymer, which is characterized by a longer wetting time than the non-ionic alkyl ethoxylate, disrupts the emulsion and allows the now-coated sulfur particles to escape the existing emulsion. The composition may also include an alkyl alcohol and/or glycol ether. The alkyl alcohol augments the emulsion-breaking capabilities of the diblock copolymer by providing additional surface tension reduction to the system, as well as emulsion inhibition at the aqueous-gaseous interface. The glycol ether acts as a mutual solvent, which also augments the emulsion breaking capabilities of the diblock copolymer by providing additional surface tension reduction to the system, as well as emulsion inhibition at the aqueous-gaseous interface.
1. A method for converting sulfur species that are present in a sour gas stream into at least one of solid sulfur or solid sulfur species, comprising the steps of:
introducing a surfactant to the sour gas stream, comprising introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate;
introducing a reagent to the sour gas stream; and
introducing an oxidizer to the sour gas stream.
2. The method of claim 1 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate with greater than 0% and up to 50% by weight of a glycol ether.
3. The method of claim 1 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate with greater than 0% and up to 50% by weight of an alkyl alcohol.
4. The method of claim 1 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein the alkoxylated block copolymer comprises a structure: R1-[R2]n-R3, wherein R1 is an alkyl group arranged in a chain, R2 is a block copolymer, n is a number, and R3 is an end cap.
5. The method of claim 4 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate comprising an alkyl group arranged in a chain comprising at least seven carbon atoms.
6. The method of claim 4 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein at least one block of the alkoxylated block copolymer comprises polyethylene glycol, with a number of blocks between three and ten units.
7. The method of claim 6 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein at least one block of the alkoxylated block copolymer is a more hydrophobic unit than the polyethylene gylcol, and comprising at least one of: polypropylene glycol, polylactone, polycaprolactone, and/or polybutadiene.
8. The method of claim 4 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein the end cap comprises at least one of: a hydroxyl group and a short-chained alcohol of less than five carbon atoms.
9. The method of claim 1 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein the alkoxylated block copolymer comprises a Hydrophobic-Lipophilic Balance between 0 and 10.
10. The method of claim 1 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein the alcohol ethoxylate comprises a structure: R4-O—(CH2)x-OH, where R4 is an alkyl group arranged in a chain.
11. The method of claim 10 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein the alkyl group comprises at least seven carbon atoms.
12. The method of claim 1 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein the alcohol ethoxylate comprises a Hydrophobic-Lipophilic Balance between 5 and 15.
13. The method of claim 1 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein wetting time of the alcohol ethoxylate is less than half than that of the alkoxylated block copolymer.
14. The method of claim 1 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein concentration of the block copolymer is between 2- and 10-times concentration by weight of the alcohol ethoxylate.
15. The method of claim 2 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein the glycol ether comprises a structure: R5-(O—CH2)x-OH, where R5 is an alkyl group arranged in a chain and x is a number between 2 and 4.
16. The method of claim 15 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein the short-chained alkyl group comprises less than six carbon atoms.
17. The method of claim 3 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein the alkyl alcohol comprises between 2 and 8 carbon units selected from the group consisting of: ethanol, propanol, isopropanol, n-butanol, isobutanol, n-pentanol, isopentanol, hexanol, heptanol and/or octanol isomers.
18. The method of claim 2 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein the glycol ether comprises a structure R6-R7 wherein R6 is an alkyl or aryl group, and R7 is a short-chained glycol group.
19. The method of claim 15 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein the group comprises one of: methyl, ethyl, propyl, isopropyl, butyl, n-butyl, tert-butyl, phenyl, and benzyl groups.
20. The method of claim 2 wherein introducing the surfactant comprises introducing an aqueous surfactant composition comprising 0.5% to 15% by weight of an alkoxylated block copolymer and 0.5% to 15% by weight of an alcohol ethoxylate, wherein the glycol ether comprises one of: ethylene glycol (—O—CH2-CH2-OH), propylene glycol (—O—CH2-CH2-CH2-OH), and diethylene gylcol (—OCH2-CH2-O—CH2-CH2-OH).