Mechanisms of hydrogen sulfide removal by ground granulated blast furnace slag amended soil. (May 2017)

• Record Type: Journal Article
• Authors: Xie, Mengyao; Leung, Anthony Kwan; Ng, Charles Wang Wai
• Is Part Of: Chemosphere. Volume 175(2017)
• Page Start: 425
• Page End: 430
• Publication Date: 2017-05
• Subjects: H2S -- GGBS -- Sulfur -- AVS -- Regeneration; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2017.02.016
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Ground granulated blast furnace slag (GGBS) amended soil has been found able to remove gaseous hydrogen sulfide (H2 S). However, how H2 S is removed by GGBS amended soil and why GGBS amended soil can be regenerated to remove H2 S are not fully understood. In this study, laboratory column tests together with chemical analysis were conducted to investigate and reveal the mechanisms of H2 S 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 H2 S and GGBS amended soil was a combined process of oxidation and acid-base reaction. The principal mechanism to remove H2 S 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 H2 S 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. Highlights: GGBS amended soil removes H2 S through oxidation and acid-base reaction. Major products of H2 S-GGBS amended soil reaction were AVS, S(0) and thiosulfate. AVS plays a significant role in H2 S removal during regeneration and reuse cycles. Higher soil water content results in increased removal capacity.