Application for laser for measurement of atmospheric pollutants
Answers
Answered by
2
National Laser Centre (NLC) is making good progress with the development and testing of its Las-R-Map system, which uses differential absorption lidar (Dial) laser technology for the remote measurement of atmospheric pollution. NLC laser physicist Francois Germishuizen tells Mining Weekly that the system, which is currently undergoing final calibration, is capable of measuring and displaying concentration profiles and movement of atmospheric pollutants that cannot be achieved with conventional point monitoring techniques.
Although the system was designed originally for use in the industrial sector, Germishuizen believes that the mining industry, particularly companies that employ minerals-processing and beneficiating plants that are prone to causing air pollution, can also benefit from this equipment.
He explains that, by employing the Las-R-Map system, a company can quickly and accurately determine the exact nature and extent of the pollution caused by its operations.
The availability of this information, in turn, assists it to monitor the discharge of pollutants, and take swift action when legal limits are exceeded.
This makes the system a valuable tool to monitor atmospheric pollution, particularly as the introduction of new environmental legislation will increase the strictness by which laws are enforced.
According to Germishuizen, the Las-R-Map system can be customised to meet the customer’s specific requirements. It can range in size from a fully-featured mobile system, installed in a van, and capable of mapping a large variety of pollutants at a range of up to ten kilometres in distance, to a portable self-contained system, aimed at concentration mapping of single pollutants at short ranges.
“A motorised scanning mirror with an integrated visual channel can provide pointing and tracking.
“Real-time results are provided on-screen by high-speed integrated digital signal processing,” Germishuizen adds.
He explains that the system achieves its efficiency by employing the Dial technique, which uses tunable laser pulses that are transmitted towards the measurement region.
“A small fraction of the light is scattered by atmospheric particles and aerosols.
“The reflected light is collected by a large receiver telescope onto a sensitive detector.
“The transmitted laser wavelengths used in the Dial approach are chosen to coincide with the absorption features of the pollutant gas under investigation.” He adds that the concentration of the gas is derived from the differential absorption of the backscattered signals at the selected wavelengths.
The system can accurately identify to as low as parts-per-billion quantities of pollutants such as sulphur dioxide, nitrogen dioxide, ozone, benzene, and butadiene, as well as secondary pollutants and particulate-matter distribution.
If all goes according to plan, the NLC will finish pilot studies of the Las-R-Map system in a year’s time.
As the system’s expensive price tag puts it out of reach of most potential users, the NLC plans to start a measurement service, whereby it will rent its equipment and expertise to local companies.
Although the system was designed originally for use in the industrial sector, Germishuizen believes that the mining industry, particularly companies that employ minerals-processing and beneficiating plants that are prone to causing air pollution, can also benefit from this equipment.
He explains that, by employing the Las-R-Map system, a company can quickly and accurately determine the exact nature and extent of the pollution caused by its operations.
The availability of this information, in turn, assists it to monitor the discharge of pollutants, and take swift action when legal limits are exceeded.
This makes the system a valuable tool to monitor atmospheric pollution, particularly as the introduction of new environmental legislation will increase the strictness by which laws are enforced.
According to Germishuizen, the Las-R-Map system can be customised to meet the customer’s specific requirements. It can range in size from a fully-featured mobile system, installed in a van, and capable of mapping a large variety of pollutants at a range of up to ten kilometres in distance, to a portable self-contained system, aimed at concentration mapping of single pollutants at short ranges.
“A motorised scanning mirror with an integrated visual channel can provide pointing and tracking.
“Real-time results are provided on-screen by high-speed integrated digital signal processing,” Germishuizen adds.
He explains that the system achieves its efficiency by employing the Dial technique, which uses tunable laser pulses that are transmitted towards the measurement region.
“A small fraction of the light is scattered by atmospheric particles and aerosols.
“The reflected light is collected by a large receiver telescope onto a sensitive detector.
“The transmitted laser wavelengths used in the Dial approach are chosen to coincide with the absorption features of the pollutant gas under investigation.” He adds that the concentration of the gas is derived from the differential absorption of the backscattered signals at the selected wavelengths.
The system can accurately identify to as low as parts-per-billion quantities of pollutants such as sulphur dioxide, nitrogen dioxide, ozone, benzene, and butadiene, as well as secondary pollutants and particulate-matter distribution.
If all goes according to plan, the NLC will finish pilot studies of the Las-R-Map system in a year’s time.
As the system’s expensive price tag puts it out of reach of most potential users, the NLC plans to start a measurement service, whereby it will rent its equipment and expertise to local companies.
Similar questions