BEHAVIOR AND CONTROL OF METALS IN A HAZARDOUS-WASTE INCINERATOR

In conjunction with a performance test series used to develop trial burn test conditions, supplementary sampling and analysis were performed to study the behavior of metals in an incinerator's combustion system and the control of metals in the incinerator's air pollution control equipment (APCE) train. The test incinerator was a Nichols Monohearth primary chamber with an afterburner; APCE consisted of a spray dryer, a cooler/condenser, a venturi scrubber, a baffle-absorber, and a mist eliminator. Multiple metals stack sampling was performed at the inlet to the APCE system, concurrent with incinerator feed and stack sampling. Analysis of these additional samples allowed evaluation of metals partitioning in the combustion system as well as APCE removal efficiencies as a function of chlorine feed concentration and venturi differential pressure. X-Ray diffractometry was applied to selected samples to speciate any crystalline phases present, and scanning electron microscopy with energy dispersive X-ray spectroscopy was used to study the morphology, size, and composition of particles captured via conventional sampling techniques. Arsenic, beryllium, cadmium, chromium, and lead compounds were spiked at known rates, and additionally, several nontoxic metals natively present in the feeds were evaluated as potential surrogates, including copper, iron, titanium, and zinc.