Journal
SCIENCE OF THE TOTAL ENVIRONMENT
Volume 616, Issue -, Pages 572-582Publisher
ELSEVIER
DOI: 10.1016/j.scitotenv.2017.10.310
Keywords
Soil amendment; Soil washing; Metal immobilization; Bioaccessibility; Sewage sludge; Biodegradable chelant
Categories
Funding
- National Research Foundation (Republic of Korea) [NRF-2015R1D1A1A09060537]
- Hong Kong Research Grants Council [PolyU 15222115, 15223517]
Ask authors/readers for more resources
In this study, soil washing and stabilization as a two-step soil remediation strategy was performed to remediate Pb- and Cu-contaminated soils from shooting range and railway sites. Ferric nitrate (Fe(NO3)(3)) and [S,S]-ethylenediamine disuccinate (EDDS) were used as washing agents, whereas three types of sludge-derived biochars and phosphogypsum were employed as soil stabilizers. While Fe(NO3)(3) extracted larger amounts of metals compared to EDDS (84% Pb and 64% Cu from shooting range soil; 30% Pb and 40% Cu from railway site soil), it caused severe soil acidification. Both Fe(NO3)(3) and EDDS washing enhanced the mobility of residual metals in the two soils, which inmost cases could be mitigated by subsequent 2-month stabilization by sludge-derived biochars or phosphogypsum. By contrast, the metal bioaccessibility could only be reduced by soil washing. Nutrient-rich sludge-derived biochar replenished available P and K in both soils, whereas Fe(NO3)(3) washing provided available nitrogen (N). Soil amendment enhanced acid phosphatase activity but marginally improved soil dehydrogenase and urease activity in the treated soils, possibly due to the influence of residual metals. This study supported the integration of soil washing (by Fe(NO3)(3) or EDDS) with soil stabilization (by sludge-derived biochars or phosphogypsum) for accomplishing the reduction of metal mobility and bioaccessibility, while restoring the environmental quality of the treated soils. (c) 2017 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available