In order to establish a comprehensive database, we are looking for as many different types of digesters as possible. This includes digesters with and without pretreatment, as well as mesophilic and thermophilic digesters. We want to include digesters with different technologies (e.g. continuous stirred tank reactors, one- or two stage digesters, complete-mix digesters or fixed-film digesters) handling a range of substrate compositions (our primary focus is wastewater sludge (primary and waste activated sludge), but we also welcome digesters fed with manure, industrial waste, food waste or systems with co-digestion).
For all included digesters we require two independent samples to be taken from the reactor. Samples should be kept cold, as detailed in Appendix A. We recommend that the samples are send directly from the anaerobic digester to country coordinator (day-to-day delivery). After receiving the samples, a small amount of sample should be transferred to individual tubes containing a preservative (non-toxic RNAlater™). We will provide the equipment necessary to transfer sample materials and labelled tubes containing preserving agents.