Factors determining the element behavior in municipal solid waste incinerators. 1. Field studies

This paper investigates the factors determining element behavior in municip al solid waste incinerators. The method is based primarily on field measure ments in full-scale incinerators. Material flow analyses are carried out in an incinerator. The main focus is placed on the processes in the furnace. The following master variables determine element transfer behavior to the r aw gas in the furnace: (i) occurrence and distribution of the elements in t he input waste; (ii) temperature, redox conditions, and content of chlorine and of reaction partners other than oxygen and chlorine in the furnace bed , and (iii) residence time and mixing conditions in the furnace bed. Twenty -nine elements are divided into two groups with respect to their transfer b ehavior to the raw gas and to the bottom ash in the furnace. The results in dicate that the elements Si, Fe, Co, Cr, Mn, Ni, P, Al, Ca, Mg, Na, Be, Li, Ti, and K are transferred mainly to the raw gas by entrainment. Occurrence and distribution of these elements in the input waste determine primarily their transfer coefficients. Evaporation is the main transfer process for t he remaining investigated elements to the raw gas. In addition to the occur rence and distribution of the elements in the input waste, physical and che mical conditions as well as kinetics are the main factors responsible for t he different transfer behaviors between the elements F, Cu, Mo, Pb, Sn, Zn, Br, Sb, C, S, Cl, As, Cd, and Hg.