TY - JOUR
T1 - The effects of temperature and oxygen content on the PCDD/PCDFs formation in MSW fly ash
AU - Chang, Moo Been
AU - Huang, Tsai Fei
N1 - Funding Information:
Financial support by the National Science Council of the Republic of China under grant No. NSC-87-2211-E-008-018 and NSC-88-EPA-008-002 is greatly acknowledged.
PY - 2000/1
Y1 - 2000/1
N2 - In this study, the effects of the temperature, oxygen content in the gas stream and carbon content in ash particles on PCDD/Fs formation on the fly ash surface were investigated. The optimum temperatures for dioxin formation were found at 350°C for boiler ash, 300°C for cyclone ash and 250°C for ESP ash, respectively. Preliminary results indicate that the optimum temperature will decrease as the particle size decreases. When the O2 concentration is varied between 0% and 100%, the optimum oxygen content for PCDD/Fs formation is found to beat 7.5% for cyclone ash, and the PCDD/PCDF ratio increases with the increase of oxygen content. Dioxin formation is observed even for the gas containing no oxygen passed through the fly ash. Hence, other reacted routes that do not need O2 for dioxin formation take place on fly ash. The carbon content in fly ash is varied between 0% and 20% in this study, and the results have indicated that the maximum dioxin formation is to be found at 5%. The precursors are not injected into the fly ash or gas stream in all formation experiments, however, dioxin is still formed in fly ash. Consequently, other chlorinated routes besides Deacon reactions may take place on the fly ash surface.
AB - In this study, the effects of the temperature, oxygen content in the gas stream and carbon content in ash particles on PCDD/Fs formation on the fly ash surface were investigated. The optimum temperatures for dioxin formation were found at 350°C for boiler ash, 300°C for cyclone ash and 250°C for ESP ash, respectively. Preliminary results indicate that the optimum temperature will decrease as the particle size decreases. When the O2 concentration is varied between 0% and 100%, the optimum oxygen content for PCDD/Fs formation is found to beat 7.5% for cyclone ash, and the PCDD/PCDF ratio increases with the increase of oxygen content. Dioxin formation is observed even for the gas containing no oxygen passed through the fly ash. Hence, other reacted routes that do not need O2 for dioxin formation take place on fly ash. The carbon content in fly ash is varied between 0% and 20% in this study, and the results have indicated that the maximum dioxin formation is to be found at 5%. The precursors are not injected into the fly ash or gas stream in all formation experiments, however, dioxin is still formed in fly ash. Consequently, other chlorinated routes besides Deacon reactions may take place on the fly ash surface.
KW - Dioxin formation
KW - Municipal waste incinerators (MW1)
KW - Oxygen content
KW - Temperature
UR - http://www.scopus.com/inward/record.url?scp=0343819750&partnerID=8YFLogxK
U2 - 10.1016/S0045-6535(99)00227-1
DO - 10.1016/S0045-6535(99)00227-1
M3 - 期刊論文
C2 - 10665428
AN - SCOPUS:0343819750
SN - 0045-6535
VL - 40
SP - 159
EP - 164
JO - Chemosphere
JF - Chemosphere
IS - 2
ER -
