The 5th Action program of EU had the aim to achieve the 90% reduction by 2005 for emissions from municipal and hospital waste incinerators and power plants. However, in 2004 the European Dioxin Emission Inventory Project showed that there was still a large number of hospital waste incinerators with variable emission factors, which could be considered significant local sources of PCDD/Fs . Due to the high content of chlorine, hospital waste incineration can lead to the formation of PCDD/Fs, which can be released both in air and in the ashes. As far as cemetery wastes are concerned, the wood used for coffins are typically treated with preservatives such as polyvinyl chloride, creosote (a mixture of polycyclic aromatic hydrocarbons) or insecticides in light organic solvents that may induce the formation of PCDD/F s [9]. In Italy PCDD/Fs atmospheric emission factors from hospital waste incineration have been reported as 0.8 ?g ITEQ t-1 of waste, but as yet very few emission data are available for this sector. With the aim to increase the database for PCDD/Fs emission inventory, an experimental campaign was carried out on a full-scale incineration plant where hospital and cemetery wastes were combusted. A second objective of this campaign was to check on a full scale plant the hypothesis of de novo synthesis reactions that may occur in the heat exchanger. This hypothesis was checked by performing the pollutant mass balance in the heat exchanger unit. The experimental campaign on hospital and cemetery wastes incineration showed that PCDD/Fs emission factors for air (2.3-44 ?g ITEQ t-1 of burned waste) were comparable with those provided by the Dioxin Toolkit for incineration plants of class 4 (continuous combustion with sophisticated APCS). On the other hand, the emission factors through solid residues (mainly fly ashes) spanned from 41 up to 3 700 ?g ITEQ t-1 of waste and can be broadly considered of the same order of magnitude of values given for class 3 (controlled, batch type combustion, with good APCS in place). In spite of the fact that the APCS included a bag filter and a scrubber, PCDD/Fs concentration at the stack was always higher than the limit of 0.1 ng Nm-3 set by the European Directive 2000/76. Similarly, PCDD/Fs concentrations in the fly ashes were generally higher than the limit of 10 ?g kg-1 (ITEQ) for disposal in hazardous waste landfill sites provided by the European Directive 99/31. The PCDD/Fs mass balance regarding the heat exchanger did not confirm the hypothesis of the de novo formation of PCDD/F occurring during the heat exchange process.
EMISSION OF DIOXINS AND FURANS FROM HOSPITAL AND CEMETERY WASTE INCINERATION
MARANI D;MININNI G;SBRILLI A;BRAGUGLIA CM;GUERRIERO E;ROTATORI M;LOTITO V
2007
Abstract
The 5th Action program of EU had the aim to achieve the 90% reduction by 2005 for emissions from municipal and hospital waste incinerators and power plants. However, in 2004 the European Dioxin Emission Inventory Project showed that there was still a large number of hospital waste incinerators with variable emission factors, which could be considered significant local sources of PCDD/Fs . Due to the high content of chlorine, hospital waste incineration can lead to the formation of PCDD/Fs, which can be released both in air and in the ashes. As far as cemetery wastes are concerned, the wood used for coffins are typically treated with preservatives such as polyvinyl chloride, creosote (a mixture of polycyclic aromatic hydrocarbons) or insecticides in light organic solvents that may induce the formation of PCDD/F s [9]. In Italy PCDD/Fs atmospheric emission factors from hospital waste incineration have been reported as 0.8 ?g ITEQ t-1 of waste, but as yet very few emission data are available for this sector. With the aim to increase the database for PCDD/Fs emission inventory, an experimental campaign was carried out on a full-scale incineration plant where hospital and cemetery wastes were combusted. A second objective of this campaign was to check on a full scale plant the hypothesis of de novo synthesis reactions that may occur in the heat exchanger. This hypothesis was checked by performing the pollutant mass balance in the heat exchanger unit. The experimental campaign on hospital and cemetery wastes incineration showed that PCDD/Fs emission factors for air (2.3-44 ?g ITEQ t-1 of burned waste) were comparable with those provided by the Dioxin Toolkit for incineration plants of class 4 (continuous combustion with sophisticated APCS). On the other hand, the emission factors through solid residues (mainly fly ashes) spanned from 41 up to 3 700 ?g ITEQ t-1 of waste and can be broadly considered of the same order of magnitude of values given for class 3 (controlled, batch type combustion, with good APCS in place). In spite of the fact that the APCS included a bag filter and a scrubber, PCDD/Fs concentration at the stack was always higher than the limit of 0.1 ng Nm-3 set by the European Directive 2000/76. Similarly, PCDD/Fs concentrations in the fly ashes were generally higher than the limit of 10 ?g kg-1 (ITEQ) for disposal in hazardous waste landfill sites provided by the European Directive 99/31. The PCDD/Fs mass balance regarding the heat exchanger did not confirm the hypothesis of the de novo formation of PCDD/F occurring during the heat exchange process.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.