Novel Mercury Control Technology for Solid Waste Incineration: Sodium Tetrasulfide (STS) as Mercury Capturing Agent
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- 作者：Yangsheng Liu ; Shaodong Xie ; Yaqiong Li ; Yushan Liu
- 刊名：Environmental Science & Technology
- 出版年：2007
- 出版时间：March 1, 2007
- 年：2007
- 卷：41
- 期：5
- 页码：1735 - 1739
- 全文大小：164K
- 年卷期：v.41,no.5(March 1, 2007)
- ISSN：1520-5851
文摘
Traditional pollution control technologies are able tocapture oxidized forms of mercury to some extent; however,they show low efficiency for the control of elementalmercury emissions. This study developed a novel mercuryremoval technology: injection of sodium tetrasulfide(Na2S4) dissolved in the sodium hydroxide (NaOH) solutionin the spray-dryer system. The effects of flue gastemperature and Na2S4 level in flue gas on the mercuryremoval efficiency were investigated. Na2S4 was decomposedinto Na2S (S2-) and elemental S (S0), which reacted withHgCl2 and elemental Hg (Hg0), and HgS was then formed.Under the optimized operation parameters, this technologycan simultaneously remove over 88% of HgCl2 andmore than 90% of Hg0 from a flue gas stream containingabout 400 
g m-3 Hg0 and 1200 g m-3 HgCl2. The increasedflue gas temperature (>170 
C) and the decreased Na2S4-to-Hg mass ratio (S-Hg-R) (<2.0) had negative effectson the reactions of gaseous mercury (HgCl2 + Hg0) with ionicsulfur (S2-) and S0. All the experiments were conductedin a full scale hospital-waste incinerator with a capabilityof 20 tons per day (TPD).
g m-3 Hg0 and 1200 g m-3 HgCl2. The increasedflue gas temperature (>170 C) and the decreased Na2S4-to-Hg mass ratio (S-Hg-R) (<2.0) had negative effectson the reactions of gaseous mercury (HgCl2 + Hg0) with ionicsulfur (S2-) and S0. All the experiments were conductedin a full scale hospital-waste incinerator with a capabilityof 20 tons per day (TPD).