Simple sample digestion of sewage and sludge for multi-element analysis

Abstract A simple digestion method of sewage, sludge, and other materials in sealed ampuls for multi‐element determination is reported. The sealed samples are digested in an autoclave at 125°C and 1.2 atmosphere pressure for one hour. In a single digestion both volatile and non‐volatile elements are recovered. Comparison of this method with conventional hot plate digestion using NBS reference materials, sewage, and sludge, shows equal or better recoveries of the metals in sealed ampuls. The method is not prone to metal contamination and can be used for large numbers of samples.