Assessment of air pollutant emissions from healthcare waste incinerators of different design features

Abstract

The aim of this paper was to e valuate the levels of gaseous emissions from four different healthcare wastes incinerators in three regional hospitals and one national hospital in Dar es Salaam, Tanzania. The incinerators studied differ in terms of capacity (kg/h) and design features. Five gaseous air pollutants (CO, CO2, NOx, and SO2) were analyzed in the sampled flue gases using a portable desktop combustion gas analyzer (model KANE900 Plus). About 29, 30, 34 and 40 consecutive runs were conducted for each incinerator at Amana, Temeke, Mwananyamala, and Muhimbili National Hospital (MNH), respectively. Other properties of the flue gas analyzed include temperature (FT), combustion efficiency (CE), percent excess air, and CO/CO2 ratio. Results showed lower CE range (lowest at Ilala regional hospital (51.4%) and highest at MNH (60.0%). The highest flue temperature was detected at MNH (911°C). The CE and pollutants concentration increased with FT and decreased with percent excess air. Results indicated poor performance of the incinerators, due to higher gaseous emissions above US-EPA standards, putting communities around these hospitals at occupational and public health risks. Installation of various air pollution control devices (APCDs) as well as monitoring and inspection programs is strongly recommended. Key words: Incinerator, combustion efficiency, healthcare waste, flue gas, acidic gaseous emissions, excess air, flue gas temperature.