What is optical gas imaging?
The timely detection of gas leaks is of great importance to a company. Gas leaks can cause for unsafe situations for employees, for improductivity in a business process and for damage to the environment. To solve this there have been developed cameras which can visualize gas leaks rapidly, easily and from a safe distance. For the optical gas imaging, spectrally filtered thermal cameras can be used to visualize a significant part of the gasses that are normally invisible.
How does a gas detection camera work?
A gas detection camera measures the infrared radiation which passes through a determined gas volume. Every gas has its own spectral absorption characteristics. That means that the most gas connections absorb a part of the infrared energy, but only within a narrow range of wavelengths. Within these wavelengths a gas detection camera is able to visualize the location of a gas plume, which often looks like a smoke cloud. This beccomes possible because the infrared energy is prevented to reach the IR-detector (built into the camera). The cloud is thus the location where the energy in the specific wave length will be absorbed by the gas.
Which gasses can be visualized?
Only the gasses that absorb the infrared radiation in a filtered range (μm) can thus be detected. Helium, oxygen and nitrogen for example can not be directly observed with a gas detection camera because they can not absorb infrared radiation in a filtered range. The most hydrocarbons, such as benzene, butane and methane absorb infrared energy close to a wave length of 3.3 μm (micrometers) and a chemical such as sulfur hexafluoride (SF6) absorbs the energy close to 10.6 μm. The most FLIR cameras can visualize specific gasses near one wave length, but they are not able to visualize gasses which absorb that energy in a different wave length. In the table below, it is stated for a couple of gasses which gas detection camera matches the most.
Cooled vs Uncooled gas detection cameras
In the table can also be made a distinction between a cooled and an uncooled camera. The gas detection cameras are historically developed with a built-in cooled IR detector. These cooled cameras from FLIR use a cryocooler for an increased sensitivity and an improved image quality. This is usable for the optical gas imaging of small or low-concentrated gas leaks. Because of the increased sensitivity, a user is able to visualize gas leaks sharper and more effectively. These cooled cameras can for example be purchased to meet the environmental requirements. However the cooled camera are an expensive investment which may not be necessary in every situation.
There are also application in which the gas leaks are bigger and less complex. In this situation, an uncooled camera might be a lighter and more cost-effective solution. The uncooled camera is cheaper to produce and has moreover less maintenance costs, because no cryocooler has been processed in the camera. These cameras can for example be used for 24/7 monitoring operations.
Sensor Partners' wide range of gas detection cameras for the optical gas imaging
Sensor Partners offers a wide range of gas detection cameras for several optical optical gas imaging applications. The cameras are applicable in many different industries. Below a couple of gas detection cameras are featured and in which industry or application these cameras are deployed in.
FLIR GF309 for monitoring furnaces, stoves and boilers
Furnaces, stoves and boilers in for example the chemical,- petrochemical and utility industry can be monitored with the FLIR GF309. This cooled camera is able to rapidly measure temperatures and prevent interruptions from a safe distance while seeing through the flames. The possibility for a heat shield offers extra protection for the camera and inspector.
FLIR GFx320 for gas leaks in hazardous environments
The FLIR GFx320 is the first handheld FLIR thermal imaging camera with the Ex certification and can be used for the detection and visualization of gas leaks in and around hazardous environments (ATEX). This cooled camera due to the extreme sensitivity is capable to visualize even the smallest possible gas leaks in real-time. This camera is moreover suited to accurately monitor temperatures in these environments.
FLIR GF304 for refrigerent gas leaks in for example the food and beverages industry
Refrigerent gasses are very toxic, are bad for the environment and are heavily regulated. When refrigerent gas lekas are not tracked down this can have big consequences for the safety of employees and the public relations and financial position of a company. The FLIR GF304 is a cooled gas detection camera suited for the in real-time detection and visualisation of refrigerent gas leaks in for example the food and beverages industry, pharmacy, automotive and airconditioning.
FLIR GF77 uncooled camera for gas detection and temperature monitoring in several industries.
The FLIR GF77 is a compact uncooled gas detection camera suited for the detection and visualization of gasses such as methane, sulfur hexafluoride (SF6), ethylene, ammonia, etc. Because of the easily interchangeable lenses (Low range & High range) this camera can be ideal to use for 24/7 gas and thermal inspection operations in many different industries such as energy corporations, oil- and gas facilities, the agriculture, etc.
For more information about optical gas imaging or which gas detection camera is suited for your application you can contact with one of our experts!