US 12,487,145 B2
Autonomous fiber optic system for direct detection of CO2 leakage in carbon storage wells
Tiziana C. Bond, Livermore, CA (US); and Allan Shih-Ping Chang, San Ramon, CA (US)
Assigned to Lawrence Livermore National Security, LLC, Livermore, CA (US)
Filed by LAWRENCE LIVERMORE NATIONAL SECURITY, LLC, Livermore, CA (US)
Filed on Aug. 30, 2021, as Appl. No. 17/461,309.
Prior Publication US 2023/0069606 A1, Mar. 2, 2023
Int. Cl. G01M 3/04 (2006.01); G01N 33/00 (2006.01); G01N 33/24 (2006.01); G01M 3/22 (2006.01); G01M 3/38 (2006.01)
CPC G01M 3/047 (2013.01) [G01N 33/004 (2013.01); G01N 33/246 (2013.01); G01M 3/226 (2013.01); G01M 3/38 (2013.01); Y02C 20/40 (2020.08)] 35 Claims
OG exemplary drawing
 
1. An apparatus for detection of carbon dioxide gas leakage in a carbon storage well, comprising:
optical fiber adapted to be positioned in the carbon storage well,
a detection unit operatively connected to the optical fiber, and
a plurality of leak sensor sections incorporated in the optical fiber, said optical fiber comprising solid core portions and hollow core portions, a first of said leak sensor sections comprising a first of said hollow core portions and a first grating in said optical fiber and a second of said leak sensor sections comprising a second of said hollow core portions and a second grating in said optical fiber, wherein the first of said leak sensor sections includes at least one opening in the first of said hollow core portions or in a first junction between the first of said hollow core portions and a first of the solid core portions,
wherein said first and second gratings are configured to provide back reflection in a reverse direction along said optical fiber toward the detection unit, said first and second gratings reflecting wavelengths of light that interact with carbon dioxide gas to provide measurable absorption or Raman spectroscopy signals sensitive to the presence of said gas, the concentration of said gas or both the presence and the concentration of said gas.