Neutron Generator and Method of Use

• US 20130168542A1
• Filed: 01/31/2011
• Published: 07/04/2013
• Est. Priority Date: 01/31/2011
• Status: Active Grant

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: Navarro-Sorroche, Juan
• Granted Patent: US 8,759,748 B2
• Time in Patent Office: Days
• US Class Current: 250/256
• CPC Class Codes: G01V 5/10 using neutron sources neutron generating tubes H05H5/00; neutron sources using isotopes G21G4/00
• CPC Class Codes: H05H 3/06 Generating neutron beams targets for producing nuclear reactions H05H6/00; neutron sources G21G4/02

Abstract

A neutron generator comprises a cylindrical housing having a target rod concentrically located along a central axis of the cylindrical housing. An array of field ionization nanotips is positioned around an inner surface of the housing, where the array of nanotips extends toward the central axis. A method for logging a formation comprises deploying a logging tool having a neutron generator into a borehole. An array of nanotips is located around an inner cylindrical surface of a cylindrical housing in the neutron generator are energized. An ionizable gas proximate the array of nanotips is ionized. The ions are accelerated radially inward to bombard a titanium layer on an outer diameter of a target rod concentrically located along a central axis of the cylindrical housing to generate neutrons.

Claims

1. A neutron generator comprising:

a cylindrical housing;

a target rod concentrically located along a central axis of the cylindrical housing; and

an array of field ionization nanotips positioned around an inner surface of the housing, said array of nanotips extended toward the central axis.

2. The neutron generator of claim 1 further comprising a titanium layer deposited on an outer diameter surface of the target rod.

3. The neutron generator of claim 2 wherein the titanium layer is loaded with predominately monatomic deuterium and tritium atoms.

4. The neutron generator of claim 2 wherein the titanium layer comprises a thickness of about 5000 to about 15000 angstroms.

5. The neutron generator of claim 1 further comprising an ionizable gas proximate the plurality of nanotips.

6. The neutron generator of claim 5 wherein the ionizable gas comprises at least one of:

a deuterium gas, a tritium gas, and a combination thereof.

7. The neutron generator of claim 1 wherein the nanotips comprise at least one of:

a tungsten material, a carbon material, and a combination thereof.

8. The neutron generator of claim 6 wherein the turn-on/turn-off time is no greater than about 1 microsecond.

9. A method for generating neutrons comprising:

concentrically locating a target rod along a central axis inside a cylindrical housing; and

positioning an array of field ionization nanotips around an inner surface of the housing such that the array of nanotips extend toward the central axis.

10. The method of claim 9 further comprising depositing a titanium layer on an outer diameter of the target rod.

11. The method of claim 10 further comprising loading the titanium layer with predominately monatomic deuterium and tritium atoms.

12. The method of claim 11 further comprising energizing the array of nanotips to ionize an ionizable gas proximate the array of nanotips, and accelerating the ions to bombard the titanium layer thereby generating neutrons.

13. The method of claim 12 wherein the ionizable gas comprises at least one of:

a deuterium gas, a tritium gas, and a combination thereof.

14. The method of claim 9 further comprising forming the nanotip array from at least one of:

a tungsten material, a carbon material, and a combination thereof.

15. A method for logging a formation comprising:

deploying a logging tool having a neutron generator into a borehole;

energizing an array of nanotips located around an inner cylindrical surface of a cylindrical housing in the neutron generator;

ionizing an ionizable gas proximate the array of nanotips; and

accelerating the ions radially inward to bombard a titanium layer on an outer diameter of a target rod concentrically located along a central axis of the cylindrical housing to generate neutrons.

16. The method of claim 15 further comprising loading the titanium layer with predominately monatomic deuterium and tritium atoms.

17. The method of claim 15 wherein the ionizable gas comprises at least one of:

a deuterium gas, a tritium gas, and a combination thereof.

18. The method of claim 15 further comprising forming the nanotip array from at least one of:

a tungsten material, a carbon material, and a combination thereof.