Electrodialysis device for the desalination of water for oil and gas applications

Patent metadata

Field	Value
Publication number	US-2021069646-A1
Application number	US-201817046283-A
Country	US
Kind code	A1
Filing date	Apr 13, 2018
Priority date	Apr 13, 2018
Publication date	Mar 11, 2021
Grant date	—

Abstract

The invention relates to an electrodialysis device for the desalination of water for oil and gas applications comprising: a membrane stack comprising alternating cation- and anion-exchange membranes (2.1, 2.3) and; a plurality of spacers (2.2, 2.4), each spacer being arranged between two successive membranes; wherein at least one of the spacers (2.2, 2.4) comprises a recessed area (3.2) and a non-recessed area (3.3), the non-recessed area (3.3) surrounding the recessed area (3.2), and wherein: the spacer (2.2, 2.4) comprises a central opening (3.1) within the recessed area (3.2); the spacer (2.2, 2.4) is provided with at least four orifices (3.4, 3.5) within the non-recessed area (3.3); the spacer (2.2, 2.4) is provided with respective channels (3.6) which connect at least two of the orifices (3.4) with the central opening (3.1); and one cation-exchange or anion-exchange membrane (2.1, 2.3) is accommodated in the recessed area (3.2). The invention also relates to a water desalination process using the electrodialysis device mentioned above, a process for extracting hydrocarbons from a subterranean formation, as well as a process for the desalination of water performed at a temperature from 35 to 80° C.

First claim

1 .- 47 . (canceled)

48 . An electrodialysis device for desalination of water in an oil and gas environment, the electrodialysis device comprising:
a membrane stack comprising alternating cation- and anion-exchange membranes; and a plurality of spacers, each spacer being arranged between two successive membranes; wherein at least one of the spacers comprises a recessed area and a non-recessed area, the non-recessed area surrounding the recessed area, and wherein: the spacer comprises a central opening within the recessed area; the spacer is provided with at least four orifices within the non-recessed area; the spacer is provided with respective channels which connect at least two of the orifices with the central opening; and a cation-exchange or anion-exchange membrane is accommodated in the recessed area.

49 . The device of claim 48 , wherein a spacer net is arranged in the central opening of the spacer and wherein the spacer net has an average thickness from 55 to 95% of the recessed area of the spacer at a temperature of 20° C.

50 . The device of claim 50 , wherein the average thickness of the spacer net is less than the average thickness of the recessed area of the spacer by 0.00 to 0.05 mm, at a temperature of 70° C.

51 . The device of claim 48 , wherein the spacer is substantially rectangular- or square-shaped and has a width and a height, and wherein the spacer has a height-to-width ratio from 1:1 to 4:1.

52 . The device of claim 48 , wherein the recessed area of the spacer has a width around the central opening which is lower than 30 mm, and/or wherein the recessed area has a depth relative to the non-recessed area which is equal to or up to 50 μm lower than the average thickness of the membrane accommodated in the recessed area, at temperature of 20° C., and/or wherein the recessed area of the spacer has a width around the central opening and the distance between each orifice and the membrane is at least equal to the width of the recessed area.

53 . The device of claim 48 , wherein the spacer comprises a single part or wherein the spacer comprises two or more stacked parts.

54 . The device of claim 48 , wherein the spacer comprises a spacer core having a central opening, stacked with at least one membrane frame having a central opening larger than the central opening of the spacer core.

55 . The device of claim 54 , wherein the spacer further comprises a cover sheet stacked between the spacer core and the membrane frame.

56 . The device of claim 55 , wherein the spacer further comprises an additional cover sheet, the spacer core being stacked between the cover sheet and the additional cover sheet.

57 . The device of claim 55 , wherein the cover sheet has a central opening which is smaller than the central opening of the membrane frame.

58 . The device of claim 48 , wherein the membrane stack comprises two adjacent cation-exchange membranes at one end of the membrane stack, or wherein the membrane stack comprises two adjacent cation-exchange membranes at each end of the membrane stack.

59 . A water desalination process for oil and gas applications comprising:
feeding an input stream to the electrodialysis device of claim 1 ; and collecting a diluate and a concentrate.

60 . The process of claim 59 , wherein the input stream is produced water or sea water or aquifer water or waste water.

61 . The process of claim 59 , wherein the input stream contains a polymer.

62 . The process of claim 59 , wherein the diluate is reinjected into a subterranean formation, or wherein the diluate is used for irrigation or wherein the diluate is used as a cooling tower make-up.

63 . The process of claim 59 , wherein the input stream has a salinity not higher than 60 g/L, and/or wherein the diluate has a salinity from 0.2 to 10 g/L.

64 . The process of claim 59 , which is performed at a temperature from 35 to 80° C.

65 . A process for extracting hydrocarbons from a subterranean formation, comprising:
injecting a water-based composition into the subterranean formation; collecting a production stream comprising hydrocarbons and produced water from at least one hydrocarbon well; and separating the production stream into at least one or more hydrocarbon streams as well as a stream of produced water; and purifying the stream of produced water according to the water desalination process of claim 59 , the stream of produced water being the input stream in said water desalination process.

66 . The process of claim 65 , wherein the stream of produced water contains a polymer.

67 . The process of claim 66 , wherein the diluate contains polymer recovered from the stream of produced water.

Assignees

• Total Se
• Mega A S
• Membrain S R O

Inventors

• Goldszal Alexandre
• Jacob Matthieu
• Tvrzník David
• Novák Lubos

Classifications

• Y02A20/124

  Water desalination · CPC title

• B01D2313/025

  Specific membrane holders · CPC title

• B01D63/0822

  Plate-and-frame devices · CPC title

• B01D61/464

  comprising the membrane sequence CC · CPC title

• B01D2313/04

  Specific sealing means · CPC title