The study of metals characteristic in ashes of a municipal solid waste incinerator

• Main Authors: Ming-Chun Tsai, 蔡明忠
• Other Authors: Chiu-Jung Liao
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/24290613085550071239

碩士 === 國立屏東科技大學 === 環境工程與科學系所 === 97 === This study determined heavy metal from different unites ash in a municipal solid waste incinerator (MSWI). The heavy metals including Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn were analyzed by sequential extraction. The ash samples collected from super heater (SH), economizer (EC), semi-dryer absorber (SDA), and fabric filter (FF), fly ash pit (FAP), and bottom residue (BR) in a municipal solid waste incinerator from South of Taiwan Experimental results showed that principal metals in the incinerator ash were Al and Fe. On average, these two metals accounted for 94.76％, 78.67％, 87.27％, 58.01％, 67.78％, 78.58％ of the total metals in SH, EC, SDA, FF and BR ash, respectively. Cd, Pb and Zn contents in ash samples from the FF were 146.2, 5403.0, 23216.1 mg/kg, respectively. Cr, Cu and Ni contents in ash samples from the BR were 1109.0, 23425.8, 338.4 mg/kg. According to this result, the ashs from SH, EC, SDA, FF, an FAP have to be solidification or stabilization before landfill. In this research, the major types of Al, Cd, Cr, Fe, Mn and Ni from sequential extraction result are Ⅵ type. Because that Cu has higher affinity with organic matters than other metals, the Ⅴ type of Cu contents 61.59%~21.37%. The Zn and Pb in ashs, which content more than 50% Ⅳ type, are easier to become Ⅳ type and conversion into oxide. The concentration of Ⅰ type and Ⅱ type in different unites ash are lower than detection limit, so moveable and bio-available type from metals are not easy to release to the environment. In statistical results, there are two groups from total content of metals and different unites ash in this study. The first group of metals is Zn, Pb, and Cd, which are semi-volatilization metals and the constant of correlation is over 0.824. The second group of metals is Ni, Cr, Mn, and Fe, which are low- volatilization metals and the constant of correlation is over 0.799.