METAL CAPTURE DURING FLUIDIZED-BED INCINERATION OF WASTES CONTAMINATED WITH LEAD CHLORIDE

The emission of toxic metals during the incineration of solid wastes containing metals presents potential environmental and health hazards. Some of the metals in the effluent gases are of submicron size which conventional air pollution control devices may not always effectively collect. One of the alternative control technologies for heavy metal emissions is to use sorbents to capture metals through various mechanisms during incineration. Of the available incineration systems, the fluidized bed incinerator appears to be suitable for this purpose. The objective of this work was to experimentally study the characteristics of metal capture by various bed sorbents during fluidized bed incineration of wastes containing lead chloride. Experiments were carried out in a 76.2 mm ID fluidized bed of sand, limestone and aluminum oxide. Combustible test materials contaminated with lead chlorides were incinerated in the bed with different sorbents under different incineration conditions. The observed results indicated that the metal capture process is highly promising. Capture efficiency was observed to range from 4.9% to 94.5% depending on sorbent type and incinerator operating conditions.