Moisture content is a critical criterion to determine the acceptability of treated sewage sludge.

Starting with fresh sludge, the moisture content should be around 70%-80%. Dried sludge (cake) needs less than 10% of moisture. The sludge is ashed at 550°C to determine the volatile solid. Volatile solids are a substance that can easily transform from its solid phase to its vapor phase without going through a liquid phase – domestic waste water volatile solids are about 50% organic. For local sewage stations with only a few samples per day the XM66 would be a perfect alternative to determine the moisture content, continuing to manually ash in a muffle.

In this application note, we determine the moisture content in sewage sludge using Precisa’s prepASH Thermogravimetric Analyser.