Wastewater disposal sludge, composed of a wide variety of substances, is effectively recycled as fertilizer. However, such recycling requires prior quality confirmation testing of the main constituents as well as the harmful constituents to ensure the safety of the resultant sludge fertilizer. In the case of fertilizer classified as 'ordinary fertilizer,' the Japan's Fertilizer Control Law specifies an official standard regarding the maximum allowable amounts of harmful substances, and minimum amounts of the necessary principle constituents that should be contained in the fertilizer.
ICP-AES (ICP Atomic Emission Spectrometry) simultaneous multi-element analysis is currently being used in a wide range of applications, and there are expectations for its greater use in fertilizer analysis. Here we introduce an analysis of fertilizer we conducted using the Shimadzu ICPE-9000 Multitype Inductively Coupled Plasma Emission Spectrometer. ICP-AES features a wide dynamic range and high sensitivity, in addition to its applicability to simultaneous multi-element analysis. It is an extremely efficient analytical method, especially when there are many target elements present in a wide concentration range, from the principle constituents to trace level substances.