The effect of developing nationsʹ municipal waste composition on PCDD/PCDF emissions from open burning

Open burning tests of municipal waste from two countries, Mexico and China, showed composition-related differences in emissions of polychlorinated dibenzodioxins and dibenzofurans (PCDDs/PCDFs). Twenty-six burn tests were conducted, comparing results from two laboratory combustion facilities. Waste was shredded to isolate composition-specific effects from those due to random waste orientation. Emissions ranged from 5 to 780 ng toxic equivalent/kg carbon burned (ng TEQ (kg Cb)−1) with an average of 140 ng TEQ (kg Cb)−1 (stdev = 170). The waste from Mexico (17 ng TEQ (kg Cb)−1) had a statistically lower average emission factor than waste from China (240 ng TEQ (kg Cb)−1. This difference was attributed primarily to waste composition differences, although one time-integrated combustion quality measure, ΔCO/ΔCO2, showed statistical significance between laboratories. However, waste composition differences were far more determinant than which laboratory conducted the tests, illustrated using both statistical techniques and comparison of cross-over samples (wastes tested at both facilities). Comparison of emissions from previous waste combustion tests in Sweden and the U.S.A, showed emission factors within the range of those determined for Mexico and China waste. For laboratory-scale combustion, existing emission factors and test methodologies are generally applicable to both developed and developing countries.