Coating carbon steel tubing with iron sulfide

Patent metadata

Field	Value
Publication number	US-2018265992-A1
Application number	US-201815919900-A
Country	US
Kind code	A1
Filing date	Mar 13, 2018
Priority date	Mar 14, 2017
Publication date	Sep 20, 2018
Grant date	—

Abstract

Treating carbon steel tubing includes contacting the carbon steel tubing with a first treatment solution including a salt; corroding the carbon steel tubing with the salt to yield a corroded surface on the carbon steel tubing; contacting the corroded surface on the carbon steel tubing with a second treatment solution comprising sulfide ions; and forming an iron sulfide layer on the corroded surface of the carbon steel tubing by chemically bonding the sulfide ions in the second treatment solution with iron in the carbon steel tubing. In some cases, the first treatment solution also includes sulfide ions, and the iron sulfide layer is formed by contacting the carbon steel tubing with the first treatment solution.

First claim

1 - 45 . (canceled)

46 . A method of treating carbon steel tubing, the method comprising:
contacting the carbon steel tubing with a first treatment solution comprising a salt; corroding the carbon steel tubing with the salt to yield a corroded surface on the carbon steel tubing; contacting the corroded surface on the carbon steel tubing with a second treatment solution comprising sulfide ions; and forming an iron sulfide layer on the corroded surface of the carbon steel tubing by chemically bonding the sulfide ions in the second treatment solution with iron in the carbon steel tubing.

47 . The method of claim 46 , wherein iron sulfide layer forms a hydrophobic coating on the carbon steel tubing.

48 . The method of claim 46 , wherein:
a temperature of the first treatment solution is at least 100° F.; the method comprises contacting the carbon steel tubing with the first treatment solution for at least five hours; a concentration of the salt in the first treatment solution is at least 100,000 ppm by weight; and a concentration of the sulfide ions in the second treatment solution is at least 50 ppm by weight.

49 . The method of claim 46 , wherein:
a temperature of the first treatment solution is at least 150° F.; the method comprises contacting the carbon steel tubing with the first treatment solution for at least ten hours; a concentration of the salt in the first treatment solution is at least 150,000 ppm by weight; and a concentration of the sulfide ions in the second treatment solution is at least 100 ppm by weight.

50 . The method claim 46 , wherein salt includes at least one of sodium, magnesium, potassium, ammonium, and calcium; and at least one of chloride, phosphate, carbonate, and bicarbonate.

51 . The method claim 48 , wherein salt includes at least one of sodium, magnesium, potassium, ammonium, and calcium; and at least one of chloride, phosphate, carbonate, and bicarbonate.

52 . The method claim 46 , wherein a thickness of the iron sulfide layer on the carbon steel tubing is at least 10 μm.

53 . The method claim 48 , wherein a thickness of the iron sulfide layer on the carbon steel tubing is at least 10 μm.

54 . The method of claim 46 , wherein a pH of the first treatment solution is in a range of 2 to 10; and a pH of the second treatment solution is in a range of 3 to 8.

55 . The method of claim 48 , wherein a pH of the first treatment solution is in a range of 2 to 10; and a pH of the second treatment solution is in a range of 3 to 8.

56 . A method of treating carbon steel tubing, the method comprising:
contacting the carbon steel tubing with a treatment solution comprising sulfide ions and a salt; corroding the carbon steel tubing with the salt to yield a corroded surface on the carbon steel tubing; and forming an iron sulfide layer on the corroded surface of the carbon steel tubing by chemically bonding the sulfide ions with iron in the carbon steel tubing.

57 . The method of claim 56 , wherein the iron sulfide layer forms a hydrophobic coating on the carbon steel tubing.

58 . The method of claim 56 , wherein:
a temperature of the treatment solution is at least 100° F.; the method comprises contacting the carbon steel tubing with the treatment solution for at least five hours; a concentration of the salt in the treatment solution is at least 100,000 ppm by weight; and a concentration of the sulfide ions in the treatment solution is at least 50 ppm by weight.

59 . The method of claim 56 , wherein:
a temperature of the treatment solution is at least 150° F.; the method comprises contacting the carbon steel tubing with the treatment solution for at least ten hours; a concentration of the salt in the treatment solution is at least 150,000 ppm by weight; and a concentration of the sulfide ions in the treatment solution is at least 100 ppm by weight.

60 . The method of claim 56 , wherein salt includes at least one of sodium, magnesium, potassium, ammonium, and calcium; and at least one of chloride, phosphate, carbonate, and bicarbonate.

61 . The method of claim 58 , wherein salt includes at least one of sodium, magnesium, potassium, ammonium, and calcium; and at least one of chloride, phosphate, carbonate, and bicarbonate.

62 . The method of claim 56 , wherein a thickness of the iron sulfide layer on the carbon steel tubing is at least 10 μm.

63 . The method of claim 58 , wherein a thickness of the iron sulfide layer on the carbon steel tubing is at least 10 μm.

64 . The method of claim 56 , wherein a pH of the treatment solution is in a range of 2 to 10.

65 . The method of claim 58 , wherein a pH of the treatment solution is in a range of 2 to 10.

Assignees

• Saudi Arabian Oil Co

Inventors

• Chang Fakuen Frank
• Chen Tao
• Wang Qiwei

Classifications

• C23F11/182 Primary

  Sulfur, boron or silicon containing compounds · CPC title

• C09K8/54

  Compositions for in situ inhibition of corrosion in boreholes or wells · CPC title

• C09K2208/32

  Anticorrosion additives · CPC title

• C23C22/50

  Treatment of iron or alloys based thereon · CPC title

• C23C22/62

  Treatment of iron or alloys based thereon · CPC title