Fingerprint of odour creation potential of sludge treatment

Recent sludge regulations in Europe have driven to build many composting and drying sites over the last few years. Within the framework of the respect of sustainable development, one of the main challenges of design and operation of such sludge treatment facilities is the control of odour nuisance. In fact, odour emissions are characterized by high variations from one site to another depending on numerous factors, including sludge composition, process design, environmental conditions, etc. Within this context, a campaign of 16 field trials was launched on several Suez Environment composting and drying sites with the objective to built a new tool for evaluation of odour creation potential of wastewater sludge. Various types of sludges were treated on different types of industrial composting and drying reactors. In each case, the reactor was monitored throughout the sludge treatment and the following compounds analysed: sulphur compounds (H2S, mercaptans, sulfides), nitrogenous compounds (ammonia and amines), aldehydes, ketones, Volatile Fatty Acids, alcohols, VOCs and odours. This work has enabled to understand the mechanisms of odour emissions involved, which are essential for the creation of adequate tools for anticipating odorous nuisance from the very first stages of a project, as well as helping with the everyday operation.