The increasing importance of biomass-based energy production as a critical component of sustainable energy resources and effective waste management necessitates a comprehensive understanding of the fundamental properties of biomass feedstocks. This review critically evaluates the physicochemical and fuel characteristics of seven widely available biomass sources in India (sugarcane bagasse, sugarcane tops, rice husk, rice straw, maize stalks, maize cobs, and empty palm oil fruit bunches), with a particular focus on the impact of torrefaction. Despite the well-documented benefits of torrefaction in improving biomass properties, limited studies have compared the specific effects of this thermal pretreatment process across diverse biomass sources. This review addresses this gap by critically analyzing the impact of torrefaction on key biomass properties, including hemicellulose, cellulose, lignin, elemental composition (carbon, hydrogen, nitrogen, and sulphur), moisture content, volatile matter, and high heating value, providing a comparative analysis to determine the optimal biomass for energy applications. Moreover, the review critically analyzes the impact of torrefaction on key biomass properties, including hemicellulose, cellulose, lignin, elemental composition (carbon, hydrogen, nitrogen, and sulphur), moisture content, volatile matter, and high heating value. Furthermore, the review synthesizes recent findings to identify optimum torrefaction conditions that enhances the properties of each corresponding biomass. By providing a comprehensive analysis of the complex relationships between biomass characteristics and their practical applications, this review contributes to the advancement of sustainable energy production by optimising biomass-based energy systems and promoting waste-to-energy strategies

The rapid growth of urbanization and the construction industry has led to increased consumption of natural resources, resulting in significant environmental impacts. This study explores the use of three locally available waste materials to develop sodium- and potassium-based alkali-activated binders. Granite dust was employed as an alternative to river sand, with replacement levels ranging from 0 to 50%, and optimized for performance. Additionally, palm oil fuel ash (POFA) was utilized as a source material, replacing slag at levels of 10% to 30% in a control mix, activated using NaOH & Na?SiO? and KOH & K?SiO? under both heat curing at 65 °C and ambient curing conditions. The mechanical and durability properties like compressive strength, water absorption, sorptivity and resistance to acids with influence of the activator, and microstructural characteristics of the binders were thoroughly analyzed. The temperatures effects of specimens were clearly analyzed and the heat cured specimens gives the 25% of lesser strength than the ambient cured AAB irrespective of activator. In both sodium and potassium based alkali activated binders. K-Nearest Neighbors and artificial neural networks were used to forecast the alkali-activated mortar’s compressive strength. Metrics used for performance evaluation, such as the coefficient of determination R2 and RMSE, showed that the ANN model produced better predictions. For sodium-based activators, ANN produced an RMSE of 0.174 and an R2 value of 0.96 under ambient curing conditions, while KNN produced an RMSE of 0.154 and an R2 value of 0.158. The findings highlight the potential use of waste materials, such as POFA, granite dust and slag in the creation of eco-friendly and high-performance alkali-activated binders

The utilization of river sand in the construction industry increases the demand and forms a several environmental impacts by degradation of river beds. It is very crucial to find the alternative materials for the sustainable development. Granite dust, M-sand, and palm oil fuel ash (POFA) are three of the most abundantly produced industrial by-products, yet their potential use as precursors and alternative fine aggregates has not been fully explored. This study comprehensively investigates the effects of incorporating varying proportions (0–50%) of granite dust into M-sand within both heat and ambient-cured alkali-activated binders (AABs) based on sodium (NaOH+Na?SiO?) and potassium (KOH+K?SiO?). POFA is utilized as a source material, replacing slag at levels of 10%, 20%, and 30% for the optimized granite dust composition. Extensive laboratory tests were performed to evaluate the physio-mechanical and durability performance of the resulting AABs, including compressive strength, water absorption, sorptivity, acid resistance, and microstructural characterization of the POFA-based alkali-activated samples using advanced analytical techniques. The results indicate that, irrespective of curing temperature, M-sand-based AABs exhibited enhanced setting behavior, compressive strength, water absorption, and porosity properties with up to 30% granite dust substitution. This improvement is attributed to the development of C-A-S-H, N-A-S-H, and K-A-S-H gel phases. In POFA-based AABs, the dense packing of POFA resulted in reduced water absorption and sorptivity compared to control specimens. Overall, the findings suggest that POFA, as a pozzolanic material, significantly improved the properties of granite dust-based AABs, offering a sustainable solution for mitigating the environmental impact and disposal challenges of industrial waste

The increased use of sugarcane bagasse in electricity production has led to a significant rise in the dumping of sugarcane bagasse ash (SCBA). To study the efficiency of SCBA as a supplementary material in the production of alkali-activated binders (AABs), which consist of quarry dust and crushed sand as fine aggregates, the present study investigates the influence of different activators, namely NaOH-NaSiO and KOH-KSiO, and the effect of curing type (ambient and heat curing) on the mechanical and durability properties of quarry dust-SCBA incorporated AAB. Various tests, including compressive strength, water absorption, sorptivity, and sulphate resistance, along with X-ray diffraction and scanning electron microscopy were conducted for AAB characterization. The results revealed that the addition of 20% quarry dust as an alternative to crushed sand in AAB is found to be optimum. The ambient-cured SCBA-blended AAB specimens demonstrated superior performance compared to their heat-cured counterparts. The Na-based SCBA blended AABs outperformed K-based AABs in resisting compressive strength reduction. The compressive strength of 28 days ambient cured Na-based and K-based AABs were found to be 47.8 and 32.4 MPa, respectively. Microstructural analysis revealed that the main hydration products in Na-based AAB are C-A-S-H, C-S-H, and N-A-S-H, while in K-based AAB, the main hydration products were found to be C-A-S-H, C-S-H, and K-A-S-H, respectively. The AAB mixtures consisting 10% SCBA found with superior performance compared to other SCBA blended AABs. However, excessive SCBA usage weakened the microstructure in both Na-based and K-based AABs. The findings demonstrate the potential for utilizing waste materials, such as SCBA and quarry dust, in the development of eco-friendly and high-performance alkali-activated binders, contributing to the reduction of environmental impact caused by the construction industry.