
Dioxin Emission Factors for the Incineration of Different Medical Waste Types
Previous research works showed that to protect public health, hospital incinerators should be provided with equipment to reduce atmospheric emissions. Most hospital incinerators do not possess such equipment, so efficient methodologies should be developed to evaluate the safety of incineration procedures. Emission factors can be used for an easy estimation of the parameters defined in legislation. Nevertheless, the actual knowledge is very scarce, mainly because previously published emission factors do not include enough information about the incinerated waste types and the respective proportion in incinerated mixture. The existence of different waste classifications also reduces the usefulness of previously published results. This study reports the first dioxin emission factors estimated for the incineration of medical waste, segregated in different types according to the classification of the Portuguese legislation. The main purpose was to evaluate the influence of waste type on emission factors, assessing how useful they are if not associated to the composition of the incinerated mixture. The study also allowed analyzing the correspondence between different waste classifications that are being used, comparing the estimated emission factors with the sole results previously published for specific waste types but segregated according to a different classification. The influence of the incinerated waste type and segregation practices on the concentration and amount of emitted dioxin was assessed, as well as the influence of segregation practices on the amount of wastes that must be incinerated. To estimate eventual hazards for human health, dioxin concentrations in combustion gas flow were compared with the respective legal limits.
Removal of products of incomplete combustion with carbon
Carbon injection and carbon beds have been used in Europe for the control of incinerator polychlorinated dibenzo-p-dioxin (dioxin) and polychlorinated dibenzofuran (furan) emissions since the 1980s. In the April 1996 proposed Hazardous Waste Combustor Maximum Achievable Control Technology standards, the US Environmental Protection Agency identified carbon injection as Beyond-the-Floor control technology for dioxin emissions from hazardous waste incinerators. In addition to dioxins and furans, data from hazardous and municipal waste incinerators have shown that carbon injection or carbon bed control will also reduce emissions of other products of incomplete combustion (PICs). This paper will qualitatively discuss the theoretical aspects of the carbon adsorption of PICs at baghouse and electrostatic precipitator temperatures and flue gas concentrations of parts per million to billion or lower. A summary of data on PIC removal with carbon from hazardous and municipal waste incinerators is also presented. Most of the carbon-PIC data described is for non-dioxin PICs. The emphasis in this paper is on non-dioxin PICs.
Survey of control technologies for low concentration organic vapor gas streams
The document presents the results of a series of studies conducted to identify commercially available control technologies suitable for application to low organic concentration gas streams at high flow rates. For this report, low concentration means 100 ppm or below, and high flows are assumed to be those above 100,000 cfm.