MERCURY OUTPUT FROM GARBAGE INCINERATION*

Domestic garbage normally contains 3-4 g Hg tonne-1. Slag and filter dust from garbage incineration contain only small quantities of mercury, which are difficult to leach. About 80-90 % of the mercury in the flue gas can be bound in the washings at condensation temperatures of 60-70 °C from a wet scrubber operated at pH 0.5-1.0 in the presence of surplus chloride. In the following neutralization of the flue gas washings with lime c. 30-40 % of the mercury can be bound as oxide; the degree of Hg precipitation can be increased to 99 % or more by adding small quantities of the precipitating agent trimercapto-s-triazine—TMT 15. The Bamberg Model for controlled depositation of residual materials containing concentrated pollutants consists of mixing the filter dust with neutralization sludge to produce a solid and only slightly permeable product. The usual concentrations of mercury in garbage incineration plants do not present a danger for the operating personnel. The mercury concentration in the residual material and emission is clearly dependent upon the percentage of used batteries, which can account for over 50 % of the total mercury. Key Words—Mercury limits in Germany, waste water, sewage sludge, workplace, emission, incineration, flue gas purification mercury emission, mercur