WRRCSR No.8:22:90 Municipal Incinerator Ash Disposal Applicable for Pacific Island Communities

Abstract

The disposal of municipal solid waste is a universal societal problem. Land disposal is the most common disposal method for these wastes. This method of disposal is becoming less attractive due to sparse availability and lack of new site locations. Incineration is an alternative treatment and disposal technology. However, this technology can produce ash containing leachable hazardous substances. A study was conducted to determine the leachability of lead, cadmium, two representatives from the polycyclic aromatic hydrocarbon (PAH) group, and one member of the dioxin group from two ash fractions and an ash-basalt solidified melt. Ash from the Waipahu, Hawai'i, incinerator was classified into three fractions. One fraction was a medium-sized ash particle, predominantly bottom ash. Another fraction was a small diameter ash particle fraction, primarily fly ash. In addition, a crushed ash-basalt melt was studied. Deionized water and reconstituted seawater were used as leaching solutions. Batch and continuous-flow leaching studies revealed that lead and cadmium can be leached from the two ash fractions; however, the targeted organic compounds were not extracted. Reconstituted seawater leached less metals from the ash than deionized water. The solidified ash-basalt melt did not release metals and targeted organics into the leaching solution.