Systems and methods for treating oilfield wastewater

Patent metadata

Field	Value
Publication number	US-10364173-B2
Application number	US-201514960939-A
Country	US
Kind code	B2
Filing date	Dec 7, 2015
Priority date	Dec 7, 2015
Publication date	Jul 30, 2019
Grant date	Jul 30, 2019

Abstract

A wastewater treatment system is disclosed that includes a desanding hydrocyclone, a deoiling hydrocyclone, an electrocoagulation apparatus that is adapted to receive a flow of treated wastewater from the desanding and deoiling hydrocyclones, a floc separator that is adapted to receive a flow of a first effluent from the electrocoagulation apparatus, and an ultrafiltration membrane apparatus that is adapted to receive at least a portion of a flow of a second effluent from the floc separator.

First claim

What is claimed:

1. A wastewater treatment system, comprising:
a desanding hydrocyclone;
a deoiling hydrocyclone;
an electrocoagulation apparatus that is adapted to receive a flow of treated wastewater from said desanding and deoiling hydrocyclones;
a floc separator that is adapted to receive a flow of a first effluent from said electrocoagulation apparatus; and
an ultrafiltration membrane apparatus that is adapted to receive at least a portion of a flow of a second effluent from said floc separator.

2. The wastewater treatment system of claim 1 , wherein said wastewater treatment system is a mobile wastewater treatment system that comprises at least one mobile trailer or at least one movable skid, wherein each of said desanding hydrocyclone, said deoiling hydrocyclone, said electrocoagulation apparatus, said floc separator, and said ultrafiltration membrane apparatus are mounted on said at least one mobile trailer or said at least one movable skid.

3. The wastewater treatment system of claim 1 , wherein said desanding hydrocyclone is adapted to receive a flow of wastewater, separate solids particles from said flow of wastewater, and direct a flow of a third effluent to said deoiling hydrocyclone, and wherein said deoiling hydrocyclone is adapted to separate hydrocarbons from said flow of said third effluent and discharge said flow of treated wastewater as a fourth effluent from said deoiling hydrocyclone.

4. The wastewater treatment system of claim 3 , wherein said desanding hydrocyclone is adapted to separate solids particles having particle sizes down to approximately 10 μm from said flow of wastewater.

5. The wastewater treatment system of claim 1 , wherein said deoiling hydrocyclone is adapted to receive a flow of wastewater, separate hydrocarbons from said flow of wastewater, and direct a flow of a third effluent to said desanding hydrocyclone, and wherein said desanding hydrocyclone is adapted to separate solids particles from said flow of said third effluent and discharge said flow of treated wastewater as a fourth effluent from said desanding hydrocyclone.

6. The wastewater treatment system of claim 1 , wherein said electrocoagulation apparatus is adapted to form agglomerated solids from at least one of suspended solids, bacterial agents, and heavy metals present in said flow of treated wastewater.

7. The wastewater treatment system of claim 6 , further comprising a chemical conditioning apparatus that is fluidly coupled to said electrocoagulation apparatus, said chemical conditioning apparatus being adapted to deliver a controlled dosage of at least one chemical binding agent to said first effluent flowing from said electrocoagulation apparatus so as to further facilitate said formation of said agglomerated solids.

8. The wastewater treatment system of claim 1 , wherein said floc separator is adapted to separate agglomerated solids from said flow of said first effluent.

9. The wastewater treatment system of claim 1 , wherein said ultrafiltration membrane apparatus is adapted to separate solids particles from said at least said portion of said flow of said second effluent.

10. The wastewater treatment system of claim 1 , further comprising a polishing filter apparatus that is adapted to receive said at least said portion of said flow of said second effluent from said floc separator, separate solids particles having particle sizes in a range of approximately 5-100 μm from said flow of said second effluent, and thereafter deliver said at least said portion of said flow of said second effluent to said ultrafiltration membrane apparatus.

11. The wastewater treatment system of claim 10 , wherein said polishing filter apparatus comprises at least one filter bag.

12. The wastewater treatment system of claim 1 , wherein said ultrafiltration membrane apparatus comprises one or more separation membranes.

13. The wastewater treatment system of claim 12 , wherein a material of said one or more separation membranes comprises silicon carbide.

14. The wastewater treatment system of claim 12 , further comprising a clean-in-place apparatus that is fluidly coupled to said ultrafiltration membrane apparatus, wherein said clean-in-place apparatus is adapted to periodically perform a clean-in-place process so as to clean said one or more separation membranes.

15. The wastewater treatment system of claim 14 , further comprising a chemical conditioning apparatus that is fluidly coupled to said clean-in-place apparatus, said chemical conditioning apparatus being adapted to deliver a controlled amount of at least one chemical to said clean-in-place apparatus during said clean-in-place process.

16. A mobile wastewater treatment system, comprising:
at least one mobile trailer or movable skid;
a desanding hydrocyclone and a deoiling hydrocyclone mounted on said at least one mobile trailer or movable skid, wherein said desanding hydrocyclone and said deoiling hydrocyclone are adapted to receive a flow of wastewater;
an electrocoagulation apparatus and a floc separator mounted on said at least one mobile trailer or movable skid, wherein said electrocoagulation apparatus is adapted to receive a flow of a substantially desanded and deoiled effluent exiting one of said desanding hydrocyclone and said deoiling hydrocyclone, and wherein said floc separator is adapted to remove agglomerated solids from a flow of an effluent exiting said electrocoagulation apparatus; and
an ultrafiltration membrane apparatus mounted on said at least one mobile trailer or movable skid, wherein said ultrafiltration membrane apparatus is adapted to remove solids particles from at least a portion of a flow of an effluent exiting said floc separator.

17. The wastewater treatment system of claim 16 , wherein said deoiling hydrocyclone is adapted to receive a flow of an effluent exiting said desanding hydrocyclone and said electrocoagulation apparatus is adapted to receive a flow of an effluent exiting said deoiling hydrocyclone.

18. The wastewater treatment system of claim 16 , wherein said desanding hydrocyclone is adapted to receive a flow of an effluent exiting said deoiling hydrocyclone and said electrocoagulation apparatus is adapted to receive a flow of an effluent exiting said desanding hydrocyclone.

19. The wastewater treatment system of claim 16 , wherein at least one of said deoiling hydrocyclone and said desanding hydrocyclone is an inline hydrocyclone.

20. The wastewater treatment system of claim 16 , wherein said floc separator comprises a compact floatation unit.

21. A method of treating wastewater with a wastewater treatment system, the method comprising:
directing a flow of wastewater to said wastewater treatment system;
separating hydrocarbons and first solids particles from said flow of wastewater with first and second hydrocyclones of said wastewater treatment system;
treating a flow of a first effluent exiting one of said first and second hydrocyclones in an electrocoagulation apparatus of said wastewater treatment system so as to form agglomerated solids from waste material present in said flow of said first effluent;
removing said agglomerated solids from a flow of a second effluent exiting said electrocoagulation apparatus with a floc separator of said wastewater treatment system; and
separating second solids particles from at least a portion of a flow of a third effluent exiting said floc separator in an ultrafiltration membrane apparatus of said wastewater treatment system.

22. The method of claim 2

Assignees

• Fmc Tech Inc

Inventors

• Seth Kushal
• Candia Eduardo
• Verbeek Paulus Henricus Joannes
• Kruijtzer Govert Lammert
• Todd Clint G
• Arreola Jr Sergio
• Ciprick Kelly P
• Hajra Suman Kalyan
• Krebs Thomas

Classifications

• C02F9/20

  Portable or detachable small-scale multistage treatment devices, e.g. point of use or laboratory water purification systems · CPC title

• C02F9/00

  Multistage treatment of water, waste water or sewage · CPC title

• C02F1/001

  Processes for the treatment of water whereby the filtration technique is of importance (C02F1/44 takes precedence; construction of filters in general B01D24/00 - B01D41/00) · CPC title

• C02F1/40

  Devices for separating or removing fatty or oily substances or similar floating material (cleaning or keeping clear the surface of open water from oil or like materials E02B15/04; devices in sewers for separating liquid or solid substances from sewage E03F5/14, e.g. for use in drains leading to the sewer E03F5/16) · CPC title

• E21B43/34

  Arrangements for separating materials produced by the well · CPC title