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LAPSE:2023.1665

Mechanical Strength, Water Seepage and Microstructure of a Novel Landfill Solidified Sludge Liner Material

Yajun Liu, Haijun Lu, Chaofeng Wang, Ye Liu, Jiayu Ma, Mengyi Liu

February 21, 2023

Abstract
In order to prepare a novel landfill liner material, we used industrial calcium-containing waste (slag, fly ash, and desulfurized gypsum) to solidify municipal sludge. The mechanical and permeability properties of the solidified sludge material (SSM) were evaluated using straight shear, uniaxial compression, and permeability tests. The hydration products, microscopic morphology, and elemental composition of the SSM after the wet and dry cycles were analyzed using a combination of scanning electron microscopy (SEM + EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). The SSM has high strength and low hydraulic conductivity. The values of cohesion c and internal friction angle φ reached 0.45−3.31 MPa and 6.52−36.28°. The SSM exhibited a compressive strength of 0.93−11.67 MPa and hydraulic conductivity of 4.80 × 10−9−1.34 × 10−7 cm/s. Analysis shows that SiO2, Al2O3, and CaO in industrial calcium-containing solid wastes and sludges produce dense bulk and agglomerated C-S-H and C-A-S-H gels under alkali excitation. The optimum ratio of sludge, desulfurized gypsum, fly ash, and slag in the solidified sludge was 1:0.61:0.62:0.54, whereas the optimum exciter was Ca(OH)2. The SSM may be used as a good barrier material to prevent water seepage in landfills.

Record ID

LAPSE:2023.1665

Keywords

industrial solid waste, landfill liner, microstructure, solidified sludge, water seepage

Subject

Materials

Suggested Citation

Liu Y, Lu H, Wang C, Liu Y, Ma J, Liu M. Mechanical Strength, Water Seepage and Microstructure of a Novel Landfill Solidified Sludge Liner Material. (2023). LAPSE:2023.1665

Author Affiliations

Liu Y: School of Civil Engineering and Architecture, Wuhan Polytechnic University, Wuhan 430023, China; State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China
Lu H: School of Civil Engineering and Architecture, Wuhan Polytechnic University, Wuhan 430023, China; State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China
Wang C: School of Civil Engineering and Architecture, Wuhan Polytechnic University, Wuhan 430023, China
Liu Y: School of Civil Engineering and Architecture, Wuhan Polytechnic University, Wuhan 430023, China; State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China
Ma J: School of Civil Engineering and Architecture, Wuhan Polytechnic University, Wuhan 430023, China; State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China
Liu M: School of Civil Engineering and Architecture, Wuhan Polytechnic University, Wuhan 430023, China; State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China

Journal Name

Processes

Volume

Issue

First Page

1641

Year

2022

Publication Date

2022-08-18

DOI:

https://doi.org/10.3390/pr10081641