Early fire detection
EVERYONE knows about serious risk fire poses for mining operations – especially when there is a risk of rapid-fire propagation or even explosion.
Thermal imaging systems can be successfully used for early detection of fire risk, often even before the fire starts.
The principle is based on non-contact temperature measurement.
Thermal cameras measure the surface temperature of the region of interest (ROI) and, based on a gradual rise in temperature are able (using appropriate software) to assess the risk that may arise before any further manifestation occurs.
This evaluation occurs automatically and continuously which is why the Applied Infrared Sensing recommends the SAFETIS system for mining operations.
The SAFETIS thermal imaging system is an excellent improvement of traditional fire detection systems in all three phases of fire:
- PHASE 1 – Gradual heating
Flames and even smoke have not started yet. There is only the risk of gradual warming.
Even though the smoke detectors do not respond, the SAFETIS system records small changes in warming and can respond ahead of fire.
- PHASE 2 – Smoke generation
Smoke detectors respond in this phase, i.e. at the time when the smoke is generated.
However, this is a risky phase where rapid escalation of destructive fire can occur.
The SAFETIS system could respond well before the occurrence of this event.
- PHASE 3 – Flare-up
In this phase, flames are visible and smoke is generated. Special CCTV cameras and the smoke detectors usually respond well to this.
However, at this stage required response is much greater and loss of property or even life can occur.
Mineral exploration
Thermal Hyperspectral Imaging is unique application of thermal imaging cameras, breaking the spectrum into a large number of bands and analysing them to detect particular materials, minerals or gases.
Traditionally, several remote sensing technologies have been used for mineral exploration – both visible-near infrared (VNIR, 0.4-1.4 ?m) and shortwave infrared (SWIR, 1.4-3.0 ?m) are well established techniques in this field.
However, the reflectance spectral features measured in the VNIR and SWIR spectral ranges are generally overtones and combination bands from fundamental absorption bands at longer wavelengths, such as in the Longwave Infrared (LWIR, 8–13.5 ?m).
The single absorption bands in the VNIR and SWIR spectral ranges are often very closely spaced so that the reflectance features measured by common spectrometers in this spectral region are typically broad and/or suffer from strong overlapping, which raises selectivity issues for mineral identification in some cases.
Since the spectral features associated with fundamental vibrations are stronger and sharper than their overtones, LWIR technologies may bring substantial selectivity improvement in certain situations.
In addition, the overtone signals of many minerals such as silicate, feldspar and olivine are too weak to give appreciable spectral features in the VNIR and SWIR.
Telops (Canada) is developing innovative solutions for mineral exploration based on Longwave Infrared (LWIR) Thermal Infrared (TIR) hyperspectral sensor technology with high spectral, spatial and temporal resolutions for cost-efficient mineralogy mapping of large cliff sections.
The instrument, named Hyper-Cam, is a lightweight and compact passive thermal infrared hyperspectral sensor for field measurements allowing surveys in various weather (cloudy, partly cloudy or clear sky) and illumination (day or night) conditions.
About 100 units have been deployed, proving this type of portable hyperspectral instruments as a tool of choice for routine field applications, such as mining exploration.
More Information:
Applied Infrared Sensing
1300 557 205
