Sulfur dioxide emissions can be detected and analyzed with satellite technology. The satellites that are best suited for this measure sunlight scattered from the ground and atmosphere.
Outotec’s sulfuric acid solutions help companies improve their sustainability by eliminating sulfur dioxide emissions (SO2) into the air. Outotec sulfuric acid plants recover the SO2 gas created in the pyro-metallurgical process and convert it into sulfuric acid via an absorption process.
SO2 emissions can be detected and analyzed with satellite technology. The satellites that are best suited for this measure sunlight scattered from the ground and atmosphere. Gases in the atmosphere absorb some of the sun’s radiation, with each gas absorbing a different part of the spectrum. This allows scientists to identify them using their individual “fingerprints” when the scattered light returns to the satellite.
Emission tracking verifies impressive results
The origin of SO2 emissions is often easier to pinpoint than that of, for example, nitrogen dioxide, which is produced by both traffic and industrial operations.
“We can measure SO2 levels through this technology from areas that are geographically or politically hard to reach, and even track the emissions of individual smelters,” says Johanna Tamminen, Research Professor, Head of Earth Observation Research Unit, Finnish Meteorological Institute (FMI). ”We have done so with two copper smelters that have invested in an Outotec sulfuric acid plant, and the results have been very clear. SO2 emissions have decreased considerably after the implementation of the sulfuric acid plants – despite increased metal production.”
One smelter in Tsumeb, Namibia, invested in a sulfuric acid plant that was completed in 2015. It is easy to see the impact of the plant by comparing satellite data from 2014 with that from 2016. Emissions have been reduced as much as 80 per cent. Another smelter, in Serbia, has produced similar results. SO2 emissions have been reduced drastically by the introduction of a new Flash Smelting line.
Computational comparison helps develop the methodology
The scientists at the FMI also compare the results from the satellite data analyses with values based on the operating parameters provided by the Wood Mackenzie Copper Smelter database for Outotec.
“The computational figures and the satellite data give similar results and follow the same curves, showing that the measuring methodology is sound. When changes occur in, for example, production volume or the ratio of sulfur and copper in the ore, we see similar changes reflected in the reported values and the satellite data. This point of comparison allows us to further develop the analytic process and our own calculations,” Tamminen says.
A new advanced satellite that can measure SO2 emissions was deployed in the fall of 2017, allowing for even more accurate measurements in the future.