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Solid waste generation and its sustainable disposal are big concerns in the present decade. Mine tailings and incinerated bottom ash are among the greatest solid waste contributors to the environment. To promote sustainable development, material reuse and recycling are important. In the present study, a feasibility study was conducted by utilizing such tailings and bottom ash for the production of controlled low-strength material (CLSM). The amount of cement was utilized less, and by controlling the design mix with a targeted flow, low-strength material was produced. Three different cement contents (60, 80, and 100 kg/m3) and 100% mine tailings or incinerated bottom ash were used as fine aggregate material. Fresh properties of different CLSM mixes, mechanical performance, and leaching behavior were conducted to confirm the final product. It was observed that both the mine tailings and bottom ashes are suitable as an aggregate material for CLSM mixes. The compressive strength values of different CLSM mixes at 28 days were observed between 0.13 and 1.88 MPa for various aggregate materials (mine tailings and bottom ash) and cement content. Moreover, there is an influence in the reactivity of cement hydration by the aggregate (tailings and ash), which was confirmed by the calorimetry study. The selected mine tailings and bottom ashes are not inert (like natural aggregate) within the CLSM mixes, and the chemical composition of the raw materials affects their fresh and hardened properties. The leaching test further shows that the final product could leach different heavy metals beyond the limit for inert materials, but within the nonhazardous limits by international standards. The present work deals with CLSM mixes with locally available industrial side streams; some important properties such as hardening time, penetration resistance, shrinkage, excavatability, and other durability properties (i.e., acid attack, freezing and thawing resistance) were not considered in the study and can be studied further. [ABSTRACT FROM AUTHOR]

Different property enhancement techniques have already been established to support upcycling of construction and demolition waste as aggregate in concrete. However, the most suitable and sustainable method is still unknown. Quality improvement of recycled coarse aggregate (RCA) after any treatment method and its environmental impact is estimated using life cycle analysis (LCA). This article compares the environmental impacts of such treatment methods on RCA and aims to find out the most suitable method with minimum impacts. The functional unit of this study is considered the preparation of 1 tonne of treated aggregate (recycled), considering reduction in water absorption after the treatment. An LCA is carried out using the SimaPro software (https://simapro.com/) followed by ISO 14040/44 guidelines. Based on the LCA environmental profiles, thermal treatment is the highest emission contributing removal method followed by mechanical grinding. In strengthening of attached mortar methods, accelerated carbonation process is the major emission contributing method followed by a specific microbial treatment. Moreover, a sensitivity analysis was performed by varying the energy mix with a focus on renewable-based energy mix. The sensitivity analysis shows a shift on selection for the suitable treatment method and other possibilities considering renewable-based energy mix. A preliminary assessment and probable impact prediction could be conceptualized before the adoption of any treatment method on RCA for a particular location. [ABSTRACT FROM AUTHOR]