Impact of Storage Duration on the Gaseous Emissions during Convective Drying of Urban Residual Sludges

Drying has become an important step within the context of sludge management. Sometimes, sludges from several wastewater treatment plants are centralized in order to dry them at an acceptable cost. Depending on sludge supply, there can be a delay between delivery and feeding into the dryer. The impact of sludge storage duration on the drying kinetics and on the exhaust emissions of volatile organic compounds (VOCs), and ammonia is investigated. Results show that, after 20 days of storage, the drying time is multiplied by 1.5, and the emissions of VOCs and NH3 are multiplied by 5 and 40, respectively.