Microbial Surfactants to Prevent and/or Remove Asphaltene Deposits
The subject invention provides compositions and methods for improving oil and/or gas production efficiency. In some embodiments, the compositions and methods utilize microbial surfactants, namely, glycolipids, to prevent the flocculation, precipitation and/or deposition of asphaltenes present in crude oil.
1 . A method for preventing or reducing flocculation, precipitation, and/or deposition onto surfaces of asphaltene molecules present in crude oil of subterranean formations, oil wells, wellbores, equipment associated therewith, the method comprising contacting the crude oil, the asphaltene molecules, and/or the surfaces with a composition comprising a glycolipid biosurfactant.
2 . The method of claim 1 , wherein the glycolipid biosurfactant is a linear sophorolipid.
3 . The method of claim 2 , wherein the linear sophorolipid has the following structure:
where R 1 and/or R 2 is a hydrogen group or an acetyl group, and R 3 is selected from the group consisting of
4 . The method of claim 1 , wherein the glycolipid biosurfactant is a lactonic sophorolipid.
5 . The method of claim 4 , wherein the lactonic sophorolipid has the following structure:
where R 1 and/or R 2 is a hydrogen group or an acetyl group, and R 3 is a saturated aliphatic hydrocarbon chain, or an unsaturated aliphatic hydrocarbon chain having at least one double bond.
6 . The method of claim 1 , wherein the composition is injected into an oil well as a formation squeeze, a batch injection or a continuous injection.
7 . The method of claim 1 , wherein the composition is injected into a crude oil storage tank.
8 . The method of claim 1 , used to prevent or reduce corrosion of equipment due to asphaltene deposits.
9 . The method of claim 1 , used to prevent or reduce blockage of tubing, pipes, and formation rock pores due to asphaltene deposition.
10 . The method of claim 1 , wherein the crude oil is heavy crude oil having an API gravity of 20° or less.
11 . The method of claim 1 , wherein the viscosity of the crude oil is reduced.
12 . The method of claim 1 , further comprising applying one or more additives in addition to the glycolipid, wherein the one or more additives are selected from: solvents, enzymes, non-biological surfactants, polymers, chelating agents, emulsifying agents, demulsifiers, lubricants, buffering agents, solubility controlling agents, pH adjusting agents, preservatives and stabilizers.
13 . The method of claim 1 , wherein the glycolipid has a purity of at least 90%.
14 . The method of claim 1 , wherein the glycolipid is in a crude form.