S. Srinivasa senthil, K. Vijayakumar^*

Energy Engineering, Vol.122, No.12, pp. 5149-5173, 2025, DOI:10.32604/ee.2025.070889 - 27 November 2025

Abstract Heating, ventilation, and air conditioning (HVAC) systems contribute substantially to global energy consumption, while rejecting significant amounts of low-grade heat into the environment. This paper presents a non-intrusive spiral-coil heat exchanger designed to recover waste heat from the outdoor condenser of a split-type air conditioner. The system operates externally without altering the existing HVAC configuration, thereby rendering it suitable for retrofitting. Water was circulated as the working fluid at flow rates of 0.028–0.052 kg/s to assess thermal performance. Performance indicators, including the outlet water temperature, heat transfer rate, convective coefficient, and efficiency, were systematically evaluated.… More >

Ilze Irbe^1,*, Laura Andze¹, Inese Filipova^1,2

Journal of Renewable Materials, Vol.13, No.11, pp. 2139-2154, 2025, DOI:10.32604/jrm.2025.02025-0107 - 24 November 2025

Abstract Growing environmental concerns and the need for sustainable alternatives to synthetic materials have led to increased interest in bio-based composites. This study investigates the development and characterization of sustainable egg packaging waste (EPW) biocomposites derived from recycled wood fibers and fungal mycelium filaments as a natural binder. Three formulations were prepared using EPW as the primary substrate, with and without the addition of hemp shives and sawdust as co-substrates. The composites were evaluated for granulometry, density, mechanical strength, hygroscopic behavior, thermal conductivity, and fire performance using cone calorimetry. Biocomposites, composed exclusively of egg packaging waste,… More >

Ahmad Faldo¹, Labanta Marbun¹, Hezekiah Lemuel Putra Zebua¹, Fateha Fateha², Rossy Choerun Nissa², Yurin Karunia Apsha Albaina Iasya³, Riri Uswatun Annifah³, Amrul Amrul¹, Yeyen Nurhamiyah^2,*

Journal of Polymer Materials, Vol.42, No.3, pp. 743-755, 2025, DOI:10.32604/jpm.2025.069981 - 30 September 2025

Abstract Conventional bioplastic production from seaweed often relies on extraction processes that are costly, time-consuming, and yield limited product. This study presents a direct fabrication method using Gracilaria sp., a red seaweed rich in polysaccharides, to produce bioplastic films without the need for extraction. Sorbitol was incorporated as a plasticizer at concentrations of 0%–10% (w/w) to modify film characteristics. Thermal analysis revealed improved stability at moderate sorbitol levels (5%–7%), while excessive plasticizer slightly reduced thermal resistance. Mechanical testing showed that sorbitol increased film flexibility and elongation at break, though tensile strength and stiffness declined. Tear strength followed More >

Jhony César Muñoz Zambrano, Douglas Alexander Bermúdez Parrales, María Antonieta Riera^*

Journal of Polymer Materials, Vol.42, No.3, pp. 837-851, 2025, DOI:10.32604/jpm.2025.067277 - 30 September 2025

Abstract Agricultural waste is a potentially interesting resource due to the compounds present. In this study, cellulose was extracted from corn stalks (Zea mays) and subsequently converted into cellulose acetate (CA). Before the extraction process, the waste sample was characterized by pH, moisture, ash, protein content, total reducing sugars (TRS), carbohydrates, cellulose, hemicellulose, and lignin. Acid and alkaline hydrolysis were performed with different reagents, concentrations, and extraction times. Sulfuric acid (H₂SO₄) and acetic acid (CH₃COOH) were used in the acid hydrolysis, while sodium hydroxide (NaOH) was used in the alkaline hydrolysis. Three concentrations (0.62, 1.25, 2.5)% and two… More >

Sarah Augustina¹, Ananda Suci Bazhafah², Jajang Sutiawan¹, Sudarmanto¹, Eko Setio Wibowo¹, Nissa Nurfajrin Solihat¹, Alvin Muhammad Savero¹, Ismadi Ismadi¹, Jayadi Jayadi³, Agus Sukarto Wismogroho⁴, Nuniek Ina Ratnaningtyas², Sukma Surya Kusumah^1,*

Journal of Renewable Materials, Vol.13, No.9, pp. 1765-1781, 2025, DOI:10.32604/jrm.2025.02025-0014 - 22 September 2025

Abstract The increasing demand for renewable energy sources has driven the exploration of innovative materials for biofuel production. This study investigates bio-pellet characteristics derived from several oyster mushroom baglog wastes with varying concentrations of molasses as an adhesive. The process began with sun-drying the baglog waste for three days, followed by oven drying at 80°C for 24 h. Bio-pellets were produced by blending baglog waste with molasses at concentrations of 5% and 10% (w/v), then subsequently fed into a pellet mill. The bio-pellets were left to rest for one hour before analysis. The quality of bio-pellets… More > Graphic Abstract

Bunyamin Bunyamin^1,2, Taufiq Saidi³, Sugiarto Sugiarto^3,4, Muttaqin Hasan^3,*

Structural Durability & Health Monitoring, Vol.19, No.5, pp. 1089-1109, 2025, DOI:10.32604/sdhm.2025.066887 - 05 September 2025

Abstract Aceh in Indonesia is rich in marine resources and abundant fishery products such as oyster. Traditionally, fishermen only harvest oysters and discard the shells, which can cause pollution and environmental contamination. Waste Oyster Shells (WOS) contain a high percentage of calcium carbonate (CaCO₃) that experiences thermal decomposition at high temperature, following the reaction CaCO₃ → CaO + CO₂ (ΔT = 825°C). At temperature > 900°C, dead-burned lime is formed, which severely influences CaO reactivity. However, the optimum temperature for producing high CaO content is still uncertain. Therefore, this study aimed to determine the optimum calcination temperature to… More > Graphic Abstract

Mujahid Tabassum^1,*, Md. Bazlul Mobin Siddique², Hadi Nabipour Afrouzi³, Saad Bin Abdul Kashem⁴

Energy Engineering, Vol.122, No.9, pp. 3433-3457, 2025, DOI:10.32604/ee.2025.065955 - 26 August 2025

Abstract Malaysia, as one of the highest producers of palm oil globally and one of the largest exporters, has a huge potential to use palm oil waste to generate electricity since an abundance of waste is produced during the palm oil extraction process. In this paper, we have first examined and compared the use of palm oil waste as biomass for electricity generation in different countries with reference to Malaysia. Some areas with default accessibility in rural areas, like those in Sabah and Sarawak, require a cheap and reliable source of electricity. Palm oil waste possesses… More >

Artem Kariev¹, Vladimir Lebedev¹, Denis Miroshnichenko^2,3, Yevgen Sokol⁴, Magomediemin Gasanov ⁵, Anna Cherkashina¹, Yuriy Lutsenko³, Serhiy Pyshyev^6,*

Journal of Renewable Materials, Vol.13, No.8, pp. 1645-1660, 2025, DOI:10.32604/jrm.2025.02025-0049 - 22 August 2025

Abstract Nowadays, the development of effective bioplastics aims to combine traditional plastics’ functionality with environmentally friendly properties. The most effective and durable modern bioplastics are made from the edible part of crops. This forces bioplastics to compete with food production because the crops that produce bioplastics can also be used for human nutrition. That is why the article’s main focus is on creating bioplastics using renewable, non-food raw materials (cellulose, lignin, etc.). Eco-friendly composites based on a renewable bioplastic blend of polybutylene adipate-co-terephthalate, corn starch, and poly(lactic acid) with reed and hemp waste as a filler.… More > Graphic Abstract

Anjie Wang^1,2, Haining Jiao^1,2,*, Zhichao Chen^1,2,*, Jie Yang^1,2

CMC-Computers, Materials & Continua, Vol.84, No.3, pp. 5773-5790, 2025, DOI:10.32604/cmc.2025.066852 - 30 July 2025

Abstract With the rapid development of the Internet of Things (IoT), artificial intelligence, and big data, waste-sorting systems must balance high accuracy, low latency, and resource efficiency. This paper presents an edge-friendly intelligent waste-sorting system that integrates a lightweight visual neural network, a pentagonal-trajectory robotic arm, and IoT connectivity to meet the requirements of real-time response and high accuracy. A lightweight object detection model, YOLO-WasNet (You Only Look Once for Waste Sorting Network), is proposed to optimize performance on edge devices. YOLO-WasNet adopts a lightweight backbone, applies Spatial Pyramid Pooling-Fast (SPPF) and Convolutional Block Attention Module… More >

Linwei Yao^1,*, Xiangning Lin^1,2, Huashen He¹, Jiahui Yang¹

Energy Engineering, Vol.122, No.8, pp. 3285-3308, 2025, DOI:10.32604/ee.2025.066628 - 24 July 2025

Abstract In order to address the synergistic optimization of energy efficiency improvement in the waste incineration power plant (WIPP) and renewable energy accommodation, an electricity-hydrogen-waste multi-energy system integrated with phase change material (PCM) thermal storage is proposed. First, a thermal energy management framework is constructed, combining PCM thermal storage with the alkaline electrolyzer (AE) waste heat recovery and the heat pump (HP), while establishing a PCM-driven waste drying system to enhance the efficiency of waste incineration power generation. Next, a flue gas treatment method based on purification-separation-storage coordination is adopted, achieving spatiotemporal decoupling between waste incineration… More >