Chemical and Microbial Aspects of Sludge Composting and Land Application

摘要

A series of six studies was conducted to evaluate selected microbial and chemical aspects of composting and sludge spreading. Ammonia (NH3 was shown to be viricidal at pH 7 to 9). Enzymatic activity was not inhibited when well stabilized or composted sludge containing high concentrations of metals and chlorinated hydrocarbons was added to soils. Nitrogen and phosphorus moved down the soil profile where plots were treated with 100 Mg/ha once or 20 Mg/ha five times. Laboratory studies of composting showed that controlled aeration to maintain temperatures between 50 and 55C allowed thermophilic decomposition to remain constant, produced more drying and CO2 than constant aeration composting. Aspergillus fumigatus and thermophilic actinomycetes, low in non-agricultural sites, are common around composting and crop residues.