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, the method comprising contacting the crude oil with a composition comprising an asphaltene dispersant and/or asphaltene inhibitor, and a linear sophorolipid having 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
wherein the composition does not comprise any lactonic sophorolipid.
2. 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.
3. The method of claim 1 , wherein the composition is injected into a crude oil storage tank.
4. The method of claim 1 , used to prevent or reduce blockage of tubing, pipes, and formation rock pores due to asphaltene deposition.
5. The method of claim 1 , wherein the crude oil is heavy crude oil having an API gravity of 20° or less.
6. The method of claim 1 , wherein the viscosity of the crude oil is reduced.
7. The method of claim 1 , further comprising applying one or more additives in addition to the linear sophorolipid, 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.
8. The method of claim 1 , wherein the one or more linear sophorolipids have a purity of at least 90%.