Jarosite is an inorganic byproduct waste produced during the purification and refining of zinc in the industry. Recycling such waste as a filler in biocomposites could be a sustainable solution to manage it. To create jute-jarosite-soy biocomposites, varying weight percentages of jarosite are combined with soy resin and applied to woven jute cloth. The impact of jarosite on the mechanical characteristics, hardness, fire retardant, thermal stability, hydrophobicity, and degrading nature of jute-soy composites was investigated, and it was discovered that its presence by a part of 3 weight percentage enhanced tensile strength by 37.2% and flexural strength by 34.7%, respectively. The hardness and thermal stability of jute-jarosite-soy composites are enhanced by 17.5% and 35.8%, respectively, over jute-soy composites. After 60 days, soil burial analyses of these composites revealed more than 70% weight loss. Due to its moderate strength and entirely biodegradable nature, manufactured jute-jarosite-soy composite can be used to replace non-degradable thermoplastic usage in several sectors.

The iron and steelmaking industry is undergoing significant transformation to meet the rising demand for steel and its components. Generally, the production of steel is a continuous process carried out by using various furnaces, including blast furnaces (BF), basic oxygen furnaces (BOF), integrated furnaces (BF and BOF), and electric arc furnaces (EAF), with distinct operating conditions. Among these, the EAF has emerged as a sustainable solution for steel production due to its utilization of recycled steel scraps and alloys. However, the processing of steel using EAF generates waste industrial slag that requires appropriate reuse to prevent environmental contamination. The EAF slag contains heavy toxic metals such as zinc (Zn), manganese (Mn), nickel (Ni), cadmium (Cd), chromium (Cr), aluminium (Al), posing risks to water and soil if disposed of in landfills, while incineration is both energy-intensive and costly. Therefore, a sustainable and cost-effective solution is imperative. Geopolymer concrete, made from waste materials, offers numerous advantages in terms of strength and durability. Despite this, there is a lack of literature on the effects of EAF slag on geopolymer concrete. The EAF slag has the potential to be utilized as aggregates or as a pozzolanic material in geopolymer composites. Recycling EAF slag in geopolymer composites not only promotes environmental sustainability but also reduces greenhouse gas emissions. This comprehensive review explores the application of EAF slag in geopolymer composites, examining its synergistic effects on the mineralogical composition, morphological characteristics, environmental consequences, and management, as well as its impact on the hardened properties of geopolymer composites.

The escalating global crisis of plastic waste necessitates innovative and sustainable approaches to its management. This study explores a novel method; the transformation of discarded plastic materials into high quality 3D printing filaments, offering a promising solution to this pervasive environmental challenge. This review paper delves into the prospects of leveraging plastic waste recycling for the production of 3D printing filaments, thereby advancing the cause of sustainable additive manufacturing. The investigation encompasses a comprehensive examination of the recycling process, encompassing waste collection, sorting, and filament extrusion. The outcomes of this study underscore the substantial potential of recycling plastic waste for 3D printing filaments as a sustainable alternative to conventional manufacturing. This review also delves into the polymer degradation phenomenon, assessment of properties of recycled polymers, and environmental impact assessment, conducting a comparative analysis with traditional filament production methods. This paper advances the application of recycling plastic waste for 3D printing filaments, offering a tangible and immediate response to the global plastic waste crisis.

A large quantity of waste slurry (WS) is produced during the process of drilled grouting piles, which is mainly composed of bentonite, clay, and metal ions. Improper disposal of WS will bring about serious environmental problems. In this study, flocculation technology and solidification technology were combined to treat WS using three types of flocculant solution, and waste slurry geopolymer concrete (WS-GPC) was prepared using treated WS, slag powder (SP), fly ash (FA) and alkali activator. The results showed 100 mL WS treated with 25 mL APAM flocculant solution with a concentration of 0.1 % had the lowest filtrate turbidity and the lowest mud moisture content (50.30 %). The bone-glue ratio, sand rate and water-to-cement ratio of the concrete samples was 3.0, 0.4 and 0.42, respectively. Taking into account the 7-day compressive strength of WS-GPC and the maximum application rate of WS, the optimal slurry cake content was 35 %. At this time, the total amount of slag powder and fly ash used was 65 %. The effects of slag powder dosage (SPD), alkali activator dosage (AAD), and alkali activator modulus (AAM) on the compressive, flexural, and splitting properties of WS-GPC were discussed. And X-ray diffraction (XRD), scanning electron microscope (SEM), and mercury intrusion porosimetry (MIP) tests were also taken to analyze the phase composition, microstructure, and pore structure of WS-GPC. There was a positive correlation between the mechanical strength of WS-GPC and SPD. While when the AAD or AAM increased, the mechanical strength of WS-GPC first increased followed by a decrease. The mechanical properties of WS-GPC with 60 % SSD, 29 % AAD and AAM being 1.3 were optimal due to more hydration products, smoother and denser microstructure, lower porosity and smaller average pore diameter of the WS-GPC. This study is expected to create a new way of green treatment of WS and provide a theoretical basis for the application of WS-GPC.

Underground infrastructure projects pose significant environmental risks due to resource consumption, ground stability issues, and potential ecological damage. This review explores sustainable practices for mitigating these impacts throughout the lifecycle of underground construction projects, focusing on recycling and reusing excavated tunnel materials. This review systematically analyzed a wide array of sustainable practices, including on-site reuse of excavated tunnel material as backfill, grouting, soil conditioning, and concrete production. Off-site reuses explored are road bases, refilling works, value-added materials, like aggregates and construction products, vegetation reclamation, and landscaping. Opportunities to recover and repurpose tunnel components like temporary support structures, known as false linings, are also reviewed. Furthermore, the potential for utilizing industrial and construction wastes in underground works are explored, such as for thermal insulation, fire protection, grouting, and tunnel lining. Incorporating green materials and energy-efficient methods in areas like grouting, lighting, and lining are also discussed. Through comprehensive analysis of numerous case studies, this review demonstrates that with optimized planning, treatment techniques, and end-use selection informed by material characterization, sustainable practices can significantly reduce the environmental footprint of underground infrastructure. However, certain approaches require further refinement and standardization, particularly in areas like the consistent assessment of recycled material properties and the development of standardized guidelines for their use in various applications. These practices contribute to broader sustainability goals by reducing resource consumption, minimizing waste generation, and promoting the use of recycled and green materials. Achieving coordinated multi-stakeholder adoption, including collaboration between contractors, suppliers, regulatory bodies, and research institutions, is crucial for maximizing the impact of these practices and accelerating the transition towards a more sustainable underground construction industry.

The conservation of the environment and the protection of natural resources are urgent and current challenges. The objective of this experimental investigation was to evaluate the potential use of aggregates derived from recycled glass waste, blast furnace slag, recycled brick waste aggregates and recycled electronic waste aggregates (textolite) as replacements for natural aggregates in cement -based composites. The experimental tests aimed to investigate how the replacement of natural aggregates with recycled waste aggregates affects various physico-mechanical parameters, including density, compressive strength, flexural strength, abrasion resistance and capillary water absorption. This investigation also included detailed microstructural analysis using optical microscopy, SEM, EDX and XRD techniques. The aim of the research was to explore the potential for soil conservation by reducing the amount of waste to be disposed of, and at the same time to conserve natural resources by identifying alternatives using recycled materials, thereby contributing to the implementation of the circular economy concept. The results of the research confirmed this potential; however, depending on the nature of the recycled aggregates, there are influences on the physico-mechanical performance of the cement composite that can be seen at the microstructural level.