Camera replaces 'sniffers' at Borealis polymer plant
25 May 2012
Stenungsund, Sweden – Borealis is using an optical gas imaging camera to detect potentially dangerous gas leaks at its low-density polyethylene (LDPE) plant in Stenungsund.
In the company’s LDPE production process highly flammable ethylene is converted into polyethylene in a high-pressure polymerisation reaction.
Borealis previously used gas ‘sniffers’– devices that measure the concentration of a certain gas in one single location and generate a concentration reading in parts per million.
The company switched to using an optical gas imaging camera, a FLIR GF306 device from FLIR Systems, in part because it allows operators to detect gases in real-time visually.
“Whereas sniffers just give you a number, an optical gas imaging camera allows you to detect gas leakage anywhere within the field of view of the camera,” a operator at Borealis explained. This speeds up the inspections considerably”.
The optical gas imaging camera has enabled Borealis to do a quick scan at every start-up: process operators are able to scan approximately 80% of the entire plant in about 30 minutes.
According to FLIR Systems, to do the same task with gas sniffers would need a team of ten people working for 48 hours.
The technology has also enhanced the safety within the Swedish plant and reduced the environmental impact of its LDPE production process, Borealis has noted. (Watch video)
The FLIR GF306 optical gas imaging camera contains a cooled Quantum Well Infrared Photodetector (QWIP) that produces thermal images with a resolution of 320 x 240 pixels at a thermal sensitivity of 25 mK (0.025 °C).
The gas visualisation functionality of the FLIR GF optical gas imaging cameras is based on infrared absorption. Gases absorb electromagnetic radiation in certain parts of the spectrum. The cameras contain a spectral filter, a focal plane array and optics that are specifically tuned to such a part of the spectral range.
Since the gas absorbs infrared radiation it blocks radiation from objects behind the gas, causing gas leaks to show up as either a black or a white plume in the thermal image, depending on whether the user opted for the ‘white hot’ or the ‘black hot’ settings.
