Akiko Kida, Yukio Noma and Kenzo Kounobe

(Hiroshima Prefectural Research Center for Environmental Science)

Abstract

The elemental contents of bottom ash and fly ash are closely related the behavior of elements in municipal incinerators. In this study, the total contents of 36 elements in ash are analyzed and the results are investigated using statistical methods. The logarithmic average of many elemental contents vary, with standard deviations of two to one half. By means of Principal Component Analysis (PCA), three principal components (PC) are selected as characteristic factors. The first PC classifies them into non-volatile (Si, Ti, etc.) and volatile (Na, K, etc.) elements. The second PC picks up metal (non-volatile or volatile) elements. The third PC is contributed by the elements which belong to groups II or III. From another point of view, ash is collected at many (6-12) points in four incinerators. The results of the correlation between Si and the other elements are argely similar to those in PCA. It is furthermore revealed that the elements such as B, Ga, Ag, etc. are correlated with the presence of Si.

Key words: chemical composition, bottom ash, fly ash, elemental correlation, municipal refuse incinerator