Studying the influence of operation parameters on heavy and alkali metals partitioning in flue gases.
In order to study the distribution and partitioning of heavy and alkali metals in the flue gases of a sewage sludge incinerator, an experiment was carried out in a pilot scale combustor. The results indicated that it was feasible to separate part of metals from flue gases by collecting fly ash at different temperatures. On the basis of their separation temperature, heavy and alkali metals could be divided into three groups: group A included Zn, K and P, which converted from gaseous phase to liquid or solid when temperature was above 600 degrees C. Pb and Cu were the metals of group B, with optimum transformation temperature of 400 degrees C. Na and As belonged to group C, with conversion temperatures of 300 degrees C. Moreover, the effect of temperature gradient on heavy and alkali metal gas-solid transformation was also experimentally investigated. It was observed that the temperature gradient could promote the gas-solid conversion of heavy and alkali metals. However, too high a temperature gradient would suppress the formation of fine particles. The peak of conversion rate for K, Pb and Na occurred at 434 degrees C s(-1), while that of P and Cu was 487 degrees C s(-1).
Han
Jun
J
Hubei Key Laboratory of Coal Conversion and New Materials, Wuhan University of Science and Technology, Wuhan, P.R. China. hanjun77@gmail.com
He
Xuanming
X
Wang
Guanghui
G
Furuuchi
Masami
M
Hata
Mitsuhiko
M
D000393:Air Pollutants / Q000032:analysis*; D005591:Chemical Fractionation; D005374:Filtration / Q000379:methods*; D005740:Gases / Q000032:analysis*; D017745:Incineration / Q000295:instrumentation / Q000379:methods*; D008672:Metals, Alkali / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification*; D019216:Metals, Heavy / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification*; D044367:Phase Transition; D013696:Temperature
D000393:Air Pollutants; D005740:Gases; D008672:Metals, Alkali; D019216:Metals, Heavy