Investigation on the Feasibility of the Use of Biosolid-Soil Mixtures for Zinc Retention in Waste Landfill Barriers

ABSTRACT

The stabilized sewage sludge, biosolid, has been widely investigated but despite numerous studies few ones have monitored the retention potential of metal ions of this material. This study aimed to investigate the zinc retention in biosolid-soil mixtures with different biosolid contents. The potential of zinc retention was evaluated using a physical model in a geotechnical centrifuge. The physical model was designed to represent a waste barrier of 3.75 m and to simulate a 1-year zinc percolation through the biosolid-soil layer. During the percolation, the zinc effluent was collected to monitoring its concentration over the time. Results show that the addition of 50% of biosolid in the soil, among other investigated proportions provided reductions up to 95% of the initial zinc concentration, considering a 300 days zinc percolation, while the natural soil, for the same period, provided reduction of 33%. The results clearly demonstrate that the incorporation of biosolid in the soil improved the zinc retention capacity. Chemical analysis suggested that the retention behavior of the biosolid is associated with the presence of organic matter and the pH value. The results are promising regarding the use of biosolid-soil mixtures in waste landfill barriers.

KEYWORDS:

• Sewage sludge
• biosolid
• heavy metal retention
• waste landfill barriers

Acknowledgments

The authors would like to acknowledge National Council for Scientific and Technological Development (CNPq) (grant number 422276/2018-9) for the financial support that made this research possible. Furthermore, the first author is thankful to Coordination for the Improvement of Higher Education Personnel (CAPES) for granting the scholarship that made the development of this research possible.

Data availability

The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research received a partial financial support from National Council for Scientific and Technological Development (CNPq) (grant number 422276/2018-9). Moreover, the first author received a scholarship from Coordination for the Improvement of Higher Education Personnel (CAPES)