초록 ▼

The present invention relates to a method and apparatus for detection of hydrogen sulfide in downhole operations. A downhole tool is provided with a coupon adapted to react at varying degrees to exposure to concentrations of hydrogen sulfide. The downhole tool is positioned in the wellbore with the

The present invention relates to a method and apparatus for detection of hydrogen sulfide in downhole operations. A downhole tool is provided with a coupon adapted to react at varying degrees to exposure to concentrations of hydrogen sulfide. The downhole tool is positioned in the wellbore with the coupon(s) exposed to downhole fluids. A reaction to a change in the coupon, such as coloration, is used to determine the presence and concentration of hydrogen sulfide.

대표청구항 ▼

What is claimed is: 1. A method of identifying the presence of hydrogen sulfide in a wellbore penetrating a subterranean formation, comprising: lowering a formation evaluation tool comprising at least one coupon operatively connected thereto into the wellbore such that the coupon is exposed to flui

What is claimed is: 1. A method of identifying the presence of hydrogen sulfide in a wellbore penetrating a subterranean formation, comprising: lowering a formation evaluation tool comprising at least one coupon operatively connected thereto into the wellbore such that the coupon is exposed to fluid in the wellbore, the at least one coupon being optically reactive to the presence of hydrogen sulfide; drawing formation fluid samples from the subterranean formation into the formation evaluation tool; determining whether an optical reaction has occurred to the at least one coupon. 2. The method of claim 1, further comprising: inspecting the at least one coupon at the surface for an optical reaction. 3. The method of claim 1, further comprising: inspecting the optical reaction of the at least one coupon to estimate the quantity of hydrogen sulfide contained in the fluid. 4. The method of claim 1, further comprising: retrieving the tool from the wellbore. 5. The method of claim 1, further comprising: taking temperature readings of the reservoir fluid. 6. The method of claim 1, further comprising: taking temperature readings of the reservoir fluid; inspecting the at least one coupon for exposure to hydrogen sulfide; and estimating the hydrogen sulfide content of the reservoir fluid based upon the inspection of the optical reaction of the at least one coupon and the temperature readings of the reservoir fluid. 7. The method of claim 1, wherein the at least one coupon is selected from a group comprising chromium, nickel and steel alloys. 8. The method of claim 1, further comprising: detecting an optical reaction of the at least one coupon with a sensor. 9. The method of claim 8, further comprising: transmitting a signal indicating an optical reaction of the at least one coupon. 10. A method for identifying the presence of hydrogen sulfide in a subsurface formation penetrated by a wellbore, comprising: lowering a formation evaluation tool into the wellbore, the tool comprising a housing, at least one coupon with a surface that is optically reactive to the presence of hydrogen sulfide, and at least one passage for conducting formation fluid to coupon drawing formation fluid samples from the subterranean formation into the formation evaluation tool; delivering formation fluid to coupon via the passage; retrieving the formation evaluation tool from the wellbore; and inspecting the coupon for an optical reaction. 11. The method of claim 10, wherein the at least one coupon is selected from a group comprising chromium, nickel and steel alloys. 12. The method of claim 10, wherein the tool comprises a plurality of of at least one coupons, the coupon capable of different optical reactions in response to varying hydrogen sulfide concentrations. 13. The method of claim 10, further comprising: taking temperature readings of the formation fluid; inspecting the optical reaction of the at least one coupon to determine if hydrogen sulfide is present; and estimating the hydrogen sulfide content of the fluid utilizing the optical reaction on the surface of the at least one coupon and the temperature readings of the formation fluid. 14. The method of claim 10, further comprising: transporting formation fluid through the formation evaluation tool; and collecting formation fluid samples within the formation evaluation tool. 15. A method for identifying the presence of hydrogen sulfide in a subsurface formations penetrated by a wellbore, comprising the steps of: lowering a formation evaluation tool into the wellbore, the tool including a housing having at least one coupon that is reactive to the presence of hydrogen sulfide and a passage for conducting formation fluid to coupon drawing formation fluid samples from the subterranean formation into the formation evaluation tool delivering formation fluid to coupon via the passages; retrieving the formation evaluation tool from the wellbore; and inspecting coupon for an optical reaction. 16. The method of claim 15, wherein the coupon is a metal. 17. The method of claim 16, wherein the metal is selected from a group comprising copper and nickel alloys. 18. The method of claim 15 wherein the coupon reacts to hydrogen sulfide by changing color. 19. A method of reservoir analysis, comprising: lowering a formation evaluation tool into a wellbore that penetrates a reservoir, the formation evaluation tool comprising at least one coupon that is optically reactive to the presence of hydrogen sulfide; flowing formation fluid through the formation evaluation tool; exposing the at least one coupon to formation fluid upon the formation fluid entry into the wellbore; taking temperature readings of the formation fluid; collecting formation fluid samples within the formation evaluation tool; retrieving the formation evaluation tool from the wellbore; inspecting the at least one coupon for an optical reaction; and estimating the hydrogen sulfide content of the formation fluid within the reservoir utilizing the inspection of the optical reaction of the at least one coupon and the temperature readings of the formation fluid. 20. A formation evaluation tool for drawing fluid from a subterranean formation therein, comprising: a housing; and at least one coupon operatively connected to the housing, the at least one coupon being optically reactive to the presence of hydrogen sulfide positioned in the housing; wherein the at least one coupon is adapted to be exposed to reservoir fluid upon the reservoir fluid entry into the apparatus. 21. The formation evaluation tool of claim 20, wherein the coupon is a metal. 22. The formation evaluation tool of claim 21, wherein the metal is selected from a group comprising comprising chromium, nickel and steel alloys. 23. The formation evaluation tool of claim 20, wherein the coupon reacts to hydrogen sulfide by changing color. 24. The formation evaluation tool of claim 20, further comprising a temperature sensor. 25. The formation evaluation tool of claim 20, further comprising a pressure sensor. 26. The formation evaluation tool of claim 20, wherein the at least one coupon comprises removable coupons having different reactive responses to hydrogen sulfide. 27. The formation evaluation tool of claim 20, wherein the housing further comprises a coupon holder that is resistant to hydrogen sulfide, the housing capable of retaining the at least one coupon. 28. The formation evaluation tool of claim 20, wherein the apparatus comprises at least three hydrogen sulfide detection coupons. 29. The formation evaluation tool of claim 20, wherein the apparatus further comprises a sensor capable of detecting a an optical reaction in the at least one coupon. 30. The formation evaluation tool of claim 29, wherein the sensor is capable of transmitting a signal indicating an optical reaction in the at least one coupon. 31. A formation evaluation tool for drawing fluid from a subterranean formation therein, comprising: a plurality of coupons that are optically reactive to the presence of hydrogen sulfide; a housing capable of retaining the coupons and having a passage for communicating formation fluids between a wellbore and the coupons; a temperature sensor; a probe capable of flowing formation fluids into the formation evaluation tool; wherein when the formation fluids are pumped through the formation evaluation tool the coupons are exposed to the formation fluid upon the formation fluid entry into the formation evaluation tool; and wherein the surface of the plurality of coupons are capable of changing color upon contact with hydrogen sulfide and can be interpreted to determine the hydrogen sulfide content in the formation fluids. 32. The formation evaluation tool of claim 31, wherein the formation evaluation tool further comprises a sensor capable of detecting an optically reaction in the at least one coupon as a result of detecting hydrogen sulfide. 33. The formation evaluation tool of claim 32, wherein the sensor is capable of transmitting a signal indicating an optically reaction in the at least one coupon as a result of detecting hydrogen sulfide. 34. An apparatus for identifying the presence of hydrogen sulfide in a wellbore penetrating a subsurface formation, comprising: a formation evaluation tool capable of drawing fluid from the subsurface formation therein including a housing having at least one coupon that is reactive to the presence of hydrogen sulfide, the housing having a passage for conducting formation fluid to the coupon when the formation evaluation tool is lowered into the wellbore. 35. The apparatus of claim 34, wherein the coupon is a metal. 36. The apparatus of claim 35, wherein the metal is selected from a group comprising copper and nickel alloys. 37. The apparatus of claim 34 wherein the coupon reacts to hydrogen sulfide by changing color.