title: Mechanisms of hydrogen sulfide removal by ground granulated blast furnace slag amended soil.
abstract: Ground granulated blast furnace slag (GGBS) amended soil has been found able to remove gaseous hydrogen sulfide (H2S). However, how H2S is removed by GGBS amended soil and why GGBS amended soil can be regenerated to remove H2S are not fully understood. In this study, laboratory column tests together with chemical analysis were conducted to investigate and reveal the mechanisms of H2S removal process in GGBS amended soil. Sulfur products formed on the surface of soil particle and in pore water were quantified. The test results reveal that the reaction between H2S and GGBS amended soil was a combined process of oxidation and acid-base reaction. The principal mechanism to remove H2S in GGBS amended soil was through the formation of acid volatile sulfide (AVS), elemental sulfur and thiosulfate. Soil pH value decreased gradually during regeneration and reuse cycles. It is found that the AVS plays a significant role in H2S removal during regeneration and reuse cycles. Adding GGBS increased the production of AVS and at the same time suppressed the formation of elemental sulfur. This mechanism is found to be more prominent when the soil water content is higher, leading to increased removal capacity.
authors.affiliation: Department of Civil and Environmental Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong. Electronic address: mxieac@connect.ust.hk.
authors.forename: Mengyao
authors.initials: M
authors.lastname: Xie
authors.affiliation: Division of Civil Engineering, University of Dundee, DD1 4HN, United Kingdom. Electronic address: a.leung@dundee.ac.uk.
authors.forename: Anthony Kwan
authors.initials: AK
authors.lastname: Leung
authors.affiliation: Department of Civil and Environmental Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong. Electronic address: cecwwng@ust.hk.
authors.forename: Charles Wang Wai
authors.initials: CWW
authors.lastname: Ng
mesh_terms: D003252:Construction Materials / Q000032:analysis; D006862:Hydrogen Sulfide / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D010084:Oxidation-Reduction; D012987:Soil / Q000737:chemistry* / Q000592:standards; D012989:Soil Pollutants / Q000032:analysis*; D013440:Sulfides / Q000032:analysis; D013455:Sulfur / Q000032:analysis; D013885:Thiosulfates / Q000032:analysis; D014867:Water / Q000032:analysis
chemical_list: D012987:Soil; D012989:Soil Pollutants; D013440:Sulfides; D013885:Thiosulfates; D014867:Water; D013455:Sulfur; D006862:Hydrogen Sulfide
keywords: AVS; GGBS; H(2)S; Regeneration; Sulfur