Neutron emission from grounded target at generator end with detection
in a compensated probe configuration using near & far detectors
Description
Mount Sopris Instrument Company, together with Starfire Industries LLC, are developing a new neutron probe that eliminates the use of radioactive materials for neutron production. This innovative solution will provide a welcome addition for well loggers and geophysicists who are restricted from using Am-Be or Deuterium-Tritium (D-T) sources.
Using a 4 Curie equivalent Deuterium-Deuterium (D-D) fusion neutron generator, the QL40-nGEN will provide radiation on/off capability, increasing safety for operators and avoiding the regulatory burden associated with radioactive sources.
Starfire Industries’ patented nGen™ technology allows for neutron generation from a grounded target located at the end of the accelerator head. This end-mounted target allows very close coupling with detectors for innovative near/far detector combinations to maximize detector sensitivity and fidelity of measurements in and around the borehole to take advantage of the 2.5 MeV monoenergetic neutron’s increased sensitivity. The high-pressure housing is sized for small diameter logging and all components are designed to withstand high ambient temperatures.
The QL40-nGEN downhole logging tool will be stackable within the Quick Link (QL) product line or it can be run as a standalone tool. It can be run in any borehole environment using the MATRIX or SCOUT data acquisition consoles. A preliminary rendering of the integrated neutron probe is shown below.
Rendering of MSI/Starfire neutron probe features
New neutron probe approximate dimensions
Applications
- Quantitative In-situ Porosity
- Petrophysical Properties
- Aquifer Quality and Delineation
- Moisture Content of Unsaturated Media
- Used with other logs, can detect gas zones and identify gas-liquid contacts
Operating Conditions
Borehole Fluid
[X] Water
[X] Mud
[X] Dry
Casing
[X] Uncased
[X] PVC Borehole
[X] Steel
Centralization
[_] Required
[X] Not Necessary
Features & Benefits
- Avoids radioactive material with safe D-D fusion
- No specialized storage required
- Ease of transport
- Simple permit for handler
- Neutron emission at end of generator allows much closer near and far placement of detectors
- Generator remains off until switched on
- Neutron generator integrated in the tool
- HV supply & RF generator integrated in neutron generator
- Onboard microcontroller with serial communications
Compare this to a Conventional Neutron Probe…
- Obtain your own radioactive source
- Purchase costly, secure storage of source
- Procure safe transport of source
- Professional license required for handling
- Neutron emission remains far from detectors
- Insurance
- Risk of lost source in the well
- Difficult for water and environmental use
Specifications – Metric/Imperial
- Base Yield: 107 n/s
- Neutron Energy: 2.5 MeV DD
- Ion Source Type: Electrodeless RF
- Lifetime: 500 hours operational warranty or 12 months on shelf
- Input Voltage: 18V, 100V DC regulated
- Input Power: 100W base, 250W option
- Operating Voltage: 120-140 kV
- Operating Temperature: 85˚C base (125˚C shallow well)
- Operating Pressure: 2900 psi (200 bar)
- Outer Diameter, Housing: 1-11/16” (43 mm)
- Inner Diameter, Components: 1.30” (33 mm)
- Length: ~ 78” (198 cm)
- Weight: ~ 25 lbs (11.34 kg)
QL Stack Possibilities
- QL40nGEN + QL40GR (Gamma) + QL40DEV (Deviation): Exploration, Borehole Deviation
- QL40nGEN + QL40GR (Gamma): Exploration, Petrophysical Properties
- QL40nGEN + QL4SGR (Spectral Gamma) + QL40ELOG (Resistivity): Groundwater Suite tools, Quantitative Analysis, Lithology, Porosity Estimates
To learn more about our classic nuclear tools:
- QL40-DEN – Dual Density + Caliper
- QL40-NEU – Neutron Thermal Neutron
- 32DEN 4-Pi – Gamma-Gamma Density
To learn more about the Starfire 100B:
The anticipated product release of the QL40-nGEN is late 2020.
