Municipal Sludge Composting Technology Evaluation

Five full-scale municipal sludge composting facilities (three static pile, one conventional windrow, and one aerated windrow) were studied to assess design, construction, operation and cost features of static pile and windrow technologies and to compare these features for municipal sludge composting applications. One static pile facility composts anaerobically digested sludge, one composts limed raw sludge, and the third composts unlimed raw sludge. Both windrow facilities compost anaerobically digested sludge. Key findings related to unit operating areas, moisture control, flexibility, process operations, odor control, and capital and operating costs are presented.