Die im Brennraum von Feuerungsanlagen für biogene Festbrennstoffe vorherrschenden Bedingungen können die Bildung von umweltrelevanten Spurenschadstoffen begünstigen. Bei hohen Temperaturen verknüpfen sich die vielfältigen Spaltprodukte des Lignins u. a. durch Ringschluss, Kondensation und Dehydrierung in komplexen Nebenreaktionen zu aromatischen Ringsystemen.
Bei den nach der 1. BImSchV eingeordneten Kleinfeuerungsanlagen stammen nach Angaben des Umweltbundesamtes mehr als 90% der gesamten Emissionen von polyzyklischen aromatischen Kohlenwasserstoffen (PAK) aus Anlagen für Holz und biogene Reststoffe [1]. Effektive Maßnahmen zur Minderung oder Verhinderung der Entstehung lassen sich einleiten, wenn die spezifischen Reaktionsbedingungen und der Ort der Entstehung bekannt sowie die theoretischen Reaktionsmechanismen praktisch nachvollziehbar sind. Demnach sind der selektive, aber vor allem zeit- und ortsaufgelöste Nachweis und die Quantifizierung von aromatischen Spurenschadstoffen zwingend notwendig.
Bisherige Online-Verfahren zum Nachweis und Messung von Schadstoffen im Spurenbereich sind zumeist hinsichtlich der Zielsubstanzen oder des Auflösungsvermögens sehr begrenzt. Speziell Methoden zum Nachweis von aromatischen Kohlenwasserstoffen stützen sich auf indirekte Sorptions- und Anreicherungsverfahren in Verbindung mit klassischen Trenn- und Detektionsverfahren wie Gaschromatographie (GC) und Massenspektrometrie (MS). Solche Messungen lassen jedoch keine Aussage über den jeweiligen Ort der Entstehung und den zeitlichen Verlauf der Emissionen zu. Die bei klassischen Ionisationsverfahren (ESI, CI) notwendige chromatische Trennung der Analyten beschränkt zudem das zeitliche Auflösungsvermögen.
[1] Struschka M.; Kilgus D.; Springmann M.; Baumbach G. (2008): Effiziente Bereitstellung aktueller Emissionsdaten für die Luftreinhaltung, UBA-FB 001217, Bd. 44-08, Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit
Copyright: | © DGAW - Deutsche Gesellschaft für Abfallwirtschaft e.V. | |
Quelle: | 4. Wissenschaftskongress März 2014 - Münster (März 2014) | |
Seiten: | 4 | |
Preis inkl. MwSt.: | € 2,00 | |
Autor: | Andreas Seidler | |
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Use of a Fabric Filter for the Sorption – What Has to be Considered? – Experiences and Solutions –
© Thomé-Kozmiensky Verlag GmbH (9/2016)
In almost all flue gas cleaning systems installed at WtE-plants, the fabric filters are central components. A good example for this is the conditioned dry sorption process which is currently preferentially used in Europe. Within the filter not only the particles and the particulate heavy metals are separated from the gas flow, but also all reaction products resulting from the separation of gaseous pollutants such as HF, HCl, SOx, heavy metals and in this respect particularly Hg as well as PCDD/PCDF. In addition to this the fabric filter constitutes an excellent reaction chamber with high additive powder density in the filter cake.
Infrasound Solution for Fouled SCR and the Economizer in World’s Largest Waste-to-Energy Boiler
© Thomé-Kozmiensky Verlag GmbH (9/2016)
Infrafone, with headquarters in Stockholm, Sweden, is using infrasound as a soot cleaning method and has plenty of experiences from various fuels and applications. The technical development has resulted in a product with much higher acoustic power than any other similar products on the market and acoustic modelling software that is unique. Infrasound cleaning increases the efficiency, the availability and the lifetime of industrial and marine boilers. In this text we start by describing the properties of infrasound and the product, while finishing by looking deeper into a couple of recent results obtained on waste to energy boilers.
Significance of and Challenges for Flue Gas Treatment Systems in Waste Incineration
© Thomé-Kozmiensky Verlag GmbH (9/2016)
Flue gas cleaning downstream of waste incineration plants had its origins in the increased construction and deployment of such plants to counter rising air pollution in the nineteen-sixties. Back then, the ever-growing burden on the environment caused lawmakers to start enacting emission limits for air pollution control. An unceasing series of environmental scandals and increasingly better analytical methods and measuring instrumentation led to a constant reduction of the emission limits and, consequently, to ongoing adjustment and further development of the necessary process stages in flue gas cleaning. As a result, today minimum emissions can be reached even under the challenging condition of deployment of a very inhomogeneous fuel (waste) and, hence, waste incineration today is no longer a key contributor to air pollution. Today, the need for flue gas cleaning is not called into doubt anymore and has long become a matter of course in the industry and in society at large. Apart from ensuring efficient elimination of noxious gases, the focus of today’s further developments is on issues such as energy efficiency, minimization of input materials and recovery and recycling of by-products from flue gas cleaning as valuable raw materials. These issues are also deemed to be key challenges, especially when it comes to selecting sites for new plants in such a manner that potential synergies can be exploited. Such aspects will also have to be considered in the plans for the predicted mega-cities of the future.
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© Thomé-Kozmiensky Verlag GmbH (9/2016)
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CO2 Capture and Re-Use at a Waste Incinerator
© Thomé-Kozmiensky Verlag GmbH (9/2016)
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