Targeting emissions – an international, interdisciplinaryeffort

Caption: Innovative measuring techniques ensure that modern waste incinerator plants emit practically no pollutants. (Photo: Waste incinerator, Niederurnen)

One of the principal aims of environmental protection is avoiding harmful emissions (or reducing them as far as possible) in order to shield mankind from dangerous substances in the air, the soil and in natural waters. An essential tool in this process is the monitoring of gaseous emissions, showing where pollutants originate and how they are transported across the world. Critical to the monitoring activities is the ability to make measurements that are as accurate as possible, so as to be able to identify the smallest concentrations of harmful substances. One of the focal areas of this year’s conference was therefore the international standardization of measurement procedures, according to CEM 2007 organizer and Empa researcher Lukas Emmenegger. “The aim is to ensure that all over the world, measurements are made the same way to yield comparable results.”
Another topic covered during the meeting, and which gave rise to animated discussion, was the need to determine mass flow, and not limit the techniques to concentration measurements. Emmenegger concedes that these are necessary but by no means the last word on the subject. “We need to move onward from the concept of emission limits and start working out the flow rates and mass balances of individual pollutants,” maintains the Empa expert. Only then will reliable information on the total quantity of greenhouse gases or other pollutants emitted be available. Data, which is needed to take appropriate environmental protection measures and to fulfill the international treaties involving emission inventories.
Another question took center stage in the debate on climate change, namely how to differentiate between carbon dioxide emissions which affect the earth’s climate (such as those from fossil fuels) and those which are biogenic (i.e. climate neutral). In this context Empa scientist Joachim Mohn presented the latest results of his work using isotope analysis, a technique which measures the proportions of carbon atoms of different atomic weights, thereby giving researchers information on the origin of the emitted CO2. This enables scientists to determine whether the emissions in question contribute to the greenhouse effect.

 

Fine particles and nanoparticles also had their platform at the CEM 2007. In Lukas Emmenegger’s opinion it is no longer sufficient in this context to merely measure the total quantity of particulate matter. “The latest instruments provide data on the size distribution and chemical composition of the particles.”All (nano)particles, it must be remembered, are not created equal; the behavior of these tiny specks of matter – and therefore the effect they have on humans and the environment – varies radically depending on their size and composition.

Internationality paired with interdisciplinarity
With its three lectures and two poster presentations, Empa as organizer and host to the CEM 2007 made a significant contribution to the scientific content of the conference. The international and interdisciplinary make-up of the speakers and participants reflected the nature of the problems being tackled. “Environmental pollution, above all in the atmosphere, does not respect national boundaries. We can only solve these kinds of problems through global cooperation,” says Emmenegger.
Representatives from El Salvador, Kazakhstan and several «neo-EU countries» took part in the conference this year for the first time, some to learn more of the essential details of the problems being tackled. That this effort pays off is demonstrated by the example of Marta Escoto de Tejada from El Salvador, who has already been a guest of Empa several times, attending courses and undertaking research in the institution’s laboratories. Back in her home country she has already successfully been putting into practice the concepts she has learnt, heading the only emissions measurement laboratory in the country and training measuring technicians. She related her experiences at the conference.
The CEM 2007 was sponsored by, among other bodies, the Joint Research Centre of the European Commission, the Swiss Federal Office for the Environment (BAFU), the Luftunion (Swiss Society for Air Quality Measurement) and the Cercl’Air (Swiss Society of Air Quality Professionals).
 

Technical information
Dr. Lukas Emmenegger, Air Pollution / Environmental Technology Laboratory, Tel. +41 44 823 46 99,