Inactivation of Sewage Sludges with Calcium Oxide Prior to Agricultural Uses

Abstract

Owing to the presence of nutrient substances and microelements (N, P, K), sludges bear a similarity to that of the manure, and may therefore effectively improve the soil structure when applied in appropriate doses. It should be noted, however, that sewage sludge have the inherent disadvantage of containing toxic substances and pathogens which might penetrate soil and contaminate vegetation by persisting there for weeks, months and even years (1). Sludges that are to be used in agriculture. require adequate treatment methods enabling complete (or, at least, partial) kill of pathogens. One of these is inactivation with quicklime.