Mechanical and Chemical Behaviour of Water Treatment Sludge and Soft Soil Mixtures for Liner Production

Background: Clay-based and geosynthetic liners are generally used as hydraulic barriers in solid waste disposal facilities, mining tailing ponds, soil-based wastewater treatment technologies, avoiding the leaching of hazardous compounds into subsoil groundwater. Water sludge (WTS) is a water plant (WTP) residue which due to properties seems decrease permeability WTS:soil mixtures may become an alternative material produce sustainable waste-based liners. Objectives: This research aims characterize analyse physical, chemical mechanical parameters WTS, soft soil four following 05:95%, 10:90%, 15:85%, 20:80% ratios, Thereby, evaluating best ratio for producing civil engineering applications. Methods: The geotechnical characterization was performed particle size distribution, specific surface, gravity, Atterberg limits, Normal Proctor compaction; composition oxides analyses through X-ray fluorescence (XRF), mineralogical description by diffraction (XRD) scanning electron microscope (SEM) with energy dispersive spectrometer (EDS) coupled imaging; behavior performing - –oedometric consolidation, consolidated undrained (CU) triaxial, falling head permeability. Tests were conducted all mixtures, soil, pointed-out exceptions. Results Discussion: results showed that fine-grained WTS filled voids but rearranged particles, thus, compacted dry unit weight decreased addition, probably its high amounts aluminium silica. compressibility did not differ significantly compared while shear strength analysis demonstrated reduction cohesion increase effective internal friction angle proportional addition. Hydraulic conductivity increased until 10% introduction, 15%, continued 20%, reaching optimum at 15%. Conclusion: incorporation can improve or just interfere soil’s be liner wastes storage ponds technologies. Furthermore, 15% (15:85% mixture) provided meeting requirement materials, i.e. , equal, lower than 10 -9 m/s. reuse this purpose would allow new added-value scope circular economy.