Chemical Engineering Transactions (Sep 2012)
Combined Flue Gas Cleaning from Persistent Organic Compounds and Nitrogen Oxides in the Multifunction Filter
Abstract
Production of new products is associated with the generation of waste that must be processed in some way. Besides recycling, as another opportunity to processing waste, there is the possibility of energetic utilization. Combustion of waste creates many pollutants that are hazardous for the environment. Pollutants, mainly nitrogen oxides (NOx), persistent organic compounds and acidic gases (SOx, HF, HCl) produced during combustion can be removed using various methods, generally comprising multiple individual devices. The 4D filtration technology can reduce the above mentioned pollutants in one device, respectively in the filter, containing catalytically active fabric bags or ceramic candles. Observations focused on reducing NOx were carried out in the industrial wastes incineration plant that was implemented by EVECO Brno, s.r.o. The filter is equipped with ceramic tubes of Clear Edge Filtration® using a multi-filtration technology, called 4D filtration. The results of operational tests focused on reducing the NOx concentration by adding aqueous ammonia solution into the flue gas stream in front of the ceramic filter will be presented. The paper presents also the results of an operation test performed on municipal solid waste incineration plant (MSWI) where cleaning of gaseous combustion products from persistent organic pollutants is achieved by the technology of catalytic filtration REMEDIATM D/F. During this operation test which was performed with the W.L.GORE, GmbH, there were carried out measurement in two regimes, differing in size of dosage of ammonia aqueous solution into the flue gas stream in order to achieve non-catalytic reduction of nitrogen oxides (SNCR). In the test was monitored the content of particular toxic polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDD/F), certain polyaromatic carbohydrons (PAH) and polychlorinated phenols (PCB), in total called persistent organic pollutants (POPs), in flue gas on the catalytic filter outlet and inlet. The efficiency of removing monitored harmful substances was slightly lower in the regime with higher ammonia dosage.