Recovering base oil from contaminated invert emulsion fluid for making new oil-/synthetic-based fluids

Patent metadata

Field	Value
Publication number	US-2016376509-A1
Application number	US-201615189665-A
Country	US
Kind code	A1
Filing date	Jun 22, 2016
Priority date	Jun 25, 2015
Publication date	Dec 29, 2016
Grant date	—

Abstract

Base oil can be recovered from contaminated O/SBF by combining a chemical process with a mechanical process. The chemical treatment includes adding a demulsifier, an anionic surfactant, a non-ionic surfactant and/or a mutual solvent to the contaminated O/SBF in an amount effective to separate the base oil from the contaminated O/SBF fluid followed by mechanical separation of oil from water, and optionally from any solids present. The recovered base oil (i.e. conventional drilling fluid, conductive drilling fluid and constant rheology drilling fluid, etc.) may then be reformulated to make a new OBM of the same type from which the base oil was recovered, or as a fuel for engines.

First claim

What is claimed is:

1 . A method of recovering base oil from a contaminated O/SBF comprising solids, and base oil and water in a water and oil emulsion, the method comprising in this sequence:
mixing at least one chemical with the contaminated O/SBF, where the at least one chemical is selected from the group consisting of demulsifiers, anionic surfactants, non-ionic surfactants, mutual solvents, microemulsions, and combinations thereof, and where the chemical is mixed in an amount effective to break the water and oil emulsion; and mechanically separating the base oil from the water and solids using a mechanical separator giving recovered base oil.

2 . The method of claim 1 further comprising:
reusing the recovered base oil in an application selected from the group of applications consisting of:
formulating a new O/SBF of the same type that the recovered base oil was separated from; and
combusting the recovered base oil in an engine and using it as a fuel source.

3 . The method of claim 1 where:
when more than one chemical is present, the total chemical concentration ranges from about 0.5 to about 8.0 vol %; and
when a single chemical is present, the total chemical concentration ranges from about 1.0 to about 5.0 vol %.

4 . The method of claim 1 where the base oil in the contaminated O/SBF fluid is selected from the group consisting of diesel, mineral oil, a synthetic base oil, esters, olefins, paraffins, and combinations thereof.

5 . The method of claim 1 where:
when the chemical is an anionic surfactant, it is an anionic surfactant having a head group selected from the group consisting of sulfate, sulfonate, phosphate, carboxylate, and combinations thereof;
when the chemical is a non-ionic surfactant, it is selected from the group consisting of alkoxylated linear alcohols, fatty acid esters, alkylpolyglucosides, alkoxylated alkyl phenols, and combinations thereof;
when the chemical is a microemulsion, the microemulsion comprises a surfactant selected from a group of anionic surfactants, non-ionic surfactants, cationic surfactants, and combinations thereof; and
when the chemical is a mutual solvent, it is selected from the group consisting of glycol ethers, alcohols, and combinations thereof.

6 . The method of claim 1 where the mechanically separating is by centrifuging.

7 . The method of claim 1 where the recovered base oil has an oil/water volume ratio of 95/5 or greater and less than 2 vol % low gravity solids.

8 . The method of claim 1 where:
the method has a feed rate of about 13 to about 15 gallons per minute (about 49 to about 57 liters per minute);
the method has a recovered base oil rate of from about 10 to about 12 gallons per minute (about 38 to about 45 liters per minute);
the recovered base oil has less than 5 vol % low gravity solids; and
the mechanically separated solids are solids remaining in the recovered oil phase having an average particle size between about 3 and about 98 microns.

9 . A method of recovering base oil from a contaminated O/SBF comprising solids, and a base oil and water in a water and oil emulsion, the method comprising in this sequence:
mixing at least one chemical with the contaminated O/SBF, where the at least one chemical is selected from the group consisting of demulsifiers, anionic surfactants, non-ionic surfactants, mutual solvents, microemulsions, and combinations thereof, and:
when more than one chemical is present, the total chemical concentration ranges from about 0.5 to about 8.0 vol %; and
when a single chemical is present, the total chemical concentration ranges from about 1.0 to about 5.0 vol %
mechanically separating the base oil from the water and solids using a three-phase centrifuge to give recovered base oil; and reusing the recovered base oil in an application selected from the group of applications consisting of:
formulating a new O/SBF of the same type that the recovered base oil was separated from; and
combusting the recovered base oil as a fuel source.

10 . The method of claim 9 where the base oil in the contaminated O/SBF is selected from the group consisting of diesel, mineral oil, a synthetic base oil, esters, olefins, paraffins and combinations thereof.

11 . The method of claim 9 where:
when the chemical is an ionic surfactant, it is an anionic surfactant having a head group selected from the group consisting of sulfate, sulfonate, phosphate, carboxylate, and combinations thereof;
when the chemical is a non-ionic surfactant, it is selected from the group consisting of alkoxylated linear alcohols, fatty acid esters, alkylpolyglucosides, alkoxylated alkyl phenols, and combinations thereof;
when the chemical is a microemulsion, the microemulsion comprises a surfactant selected from a group of anionic surfactants, nonionic surfactants, cationic surfactants, and combinations thereof; and
when the chemical is a mutual solvent, it is selected from the group consisting of glycol ethers, alcohols, and combinations thereof.

12 . The method of claim 9 where the recovered base oil has an oil/water volume ratio of 95/5 or greater and less than 2 vol % low gravity solids.

13 . The method of claim 9 where:
the method has a feed rate of about 13 to about 15 gallons per minute (about 49 to about 57 liters per minute);
the method has a recovered base oil rate of from about 10 to about 12 gallons per minute (about 38 to about 45 liters per minute);
the recovered base oil has less than 5 vol % low gravity solids; and
the mechanically separated solids are solids remaining in the recovered oil phase having an average particle size between about 3 and about 98 microns.

14 . A method of recovering base oil from a contaminated O/SBF comprising solids, and a base oil and water in a water and oil emulsion, the method comprising in this sequence:
mixing at least one chemical with the contaminated O/SBF, where the at least one chemical is selected from the group consisting of demulsifiers, anionic surfactants, non-ionic surfactants, mutual solvents, microemulsions, and combinations thereof, and:
when more than one chemical is present, the total chemical concentration ranges from about 0.5 to about 8.0 vol %; and
when a single chemical is present, the total chemical concentration ranges from about 1.0 to about 5.0 vol %
mechanically separating the base oil from the water and solids using a three-phase centrifuge to give recovered base oil; and reusing the recovered base oil in an application selected from the group of applications consisting of:
formulating a new O/SBF of the same type that the recovered base oil was separated from; and
combusting the recovered base oil as a fuel source.

where:
when the chemical is an ionic surfactant, it is an anionic surfactant having a head group selected from the group consisting of sulfate, sulfonate, phosphate, carboxylate, and combinations thereof;
when the chemical is a non-ionic surfactant, it is selected from the group consisting of alkoxylated linear alcohols, fatty acid esters, alkylpolyglucosides, alkoxylated alkyl phenols, and combinations thereof;
when the chemical is a microemulsion, the microemulsion comprises a surfactant selected from a group of anionic surfactants, nonionic surfactants, cationic surfactants, and combinations thereof; and
when the chemical is a mutual solvent, it is selected from the group consisting of glycol ethers, alcohols, and combinations thereof; and

where:
the method has a feed rate of about 13 to about 15 gallons per minute (about 49 to about 57 liters per minute);
the method has a recovered base oil rate

Assignees

• Baker Hughes Inc

Inventors

• Darugar Qusai A
• Dye Billy M
• Hussain Ibraheem T
• Mccray Melissa V

Classifications

• C09K8/36

  Water-in-oil emulsions · CPC title

• E21B21/068

  using chemical treatment · CPC title

• E21B21/065

  Separating solids from drilling fluids · CPC title

• C10G29/22 Primary

  containing oxygen as the only hetero atom · CPC title

• C10G2300/208

  Sediments, e.g. bottom sediment and water or BSW · CPC title