Industrial and Domestic Waste Management

Effect of Papaya and Shrimp Waste Bioactivators on Household Organis Waste Composting

2026-07-06T00:10:38+00:00

This study aims to evaluate the effect of papaya bioactivator (Carica papaya) and shrimp waste bioactivator on the composting process of household organic waste, as well as changes in the levels of carbon (C), nitrogen (N), phosphorus (P), potassium (K), and the C/N ratio. The study was conducted on a laboratory scale with three treatments: R1 (papaya bioactivator), R2 (shrimp waste bioactivator), and R3 (without bioactivator). The parameters observed included pH, temperature, humidity, and color on a daily basis, as well as changes in C, N, C/N ratio, P, and K levels at the beginning and end of the composting process. The results showed that the C/N ratio decreased in all treatments, while the levels of N, P, and K increased. The shrimp waste bioactivator (R2) produced the fastest composting process in 12 days and yielded the best compost quality, with the lowest C/N ratio and the highest increases in N, P, and K levels. Conversely, the treatment without bioactivator showed a slower process, with a final C/N ratio of 33.54, indicating that the compost was not yet mature. Shrimp waste bioactivators have the potential to improve the quality and efficiency of the composting process.

Applications of Lean Manufacturing to Reduce Waste in the Crumb Rubber Industry

2026-08-22T14:43:11+00:00

This study focused on reducing waste in rubber powder production using Lean Manufacturing tools and improving process cycle efficiency. A quantitative case study was conducted at PT Perkebunan Nusantara IV Region 1, Gunung Para Plantation, North Sumatra, Indonesia. Waste was identified using the types-of-waste framework and ranked according to its impact on the production process. The selection of appropriate Lean tools was guided by Value Stream Mapping (VSM). The process was analyzed using Current Value Stream Mapping (CVSM), fishbone diagrams, and Future Value Stream Mapping (FVSM). The primary objective was to identify and reduce waste in the crumb rubber production process. The major types of waste identified were waiting time, excess inventory, product defects, and overprocessing. Based on the value stream analysis, several improvement strategies were proposed. The initial process cycle efficiency was 96.26%. After the proposed improvements were applied, particularly those aimed at reducing non-value-added time in the future value stream, process cycle efficiency increased by 1.82 percentage points to 98.08%. In addition, the production lead time decreased from 16,779.32 minutes to 16,467.93 minutes, representing a reduction of 311.39 minutes. The application of Lean Manufacturing and Value Stream Mapping effectively reduced production waste and improved the overall efficiency of the crumb rubber production process.

Textile Waste Reduction through Zero-Waste Cutting Subtraction Techniques: A Fit-to-Body Couture Approach for Sustainable Micro, Small, and Medium Enterprises in Indonesia

2026-08-08T06:58:36+00:00

The production of custom-made couture by Indonesian fashion MSMEs generated significant textile waste because fit-to-body construction required patterns that precisely followed the contours of the body, while conventional cutting techniques did not efficiently accommodate this requirement. Existing zero-waste and subtraction cutting techniques had primarily been applied to loose-fitting and ready-to-wear silhouettes, with limited application to fit-to-body couture. This study developed and validated a modified subtraction cutting technique designed to produce fit-to-body couture dresses while maintaining fabric waste below 5%. An exploratory experimental method was employed using a Research through Design (RtD) approach and iterative prototyping. The research process included baseline waste assessment, pattern engineering, controlled comparative testing against conventional patterns using identical amounts of fabric, and aesthetic and fit validation by an expert panel. The results showed that the selected subtraction cutting prototype successfully reduced fabric waste from 7.64% for the conventional baseline to 4.65%, representing a relative reduction of 39.14%. The prototype also achieved a “Good” rating (74.4%) in expert validation based on aesthetic and fit-to-body criteria. The final garments were subsequently produced using patchwork materials obtained from partner MSMEs, demonstrating the practical potential for utilizing textile waste. Expert feedback identified improvement of the drapery as the primary priority for final design refinement. Overall, this study demonstrated an applicable pattern-engineering approach and provided empirical evidence that fit-to-body couture could be aligned with textile waste reduction objectives in sustainable fashion production.

Global Research Trends and Knowledge Structure of Integrated Sustainable Waste Management: Insights from a Decade of Bibliometric Evidence

2026-08-06T06:56:11+00:00

The growing complexity of waste governance has positioned Integrated Sustainable Waste Management (ISWM) as an important research domain within global sustainability studies. Although scholarly attention to ISWM continues to increase, a consolidated understanding of publication trends, disciplinary coverage, country contributions, and thematic structures remains limited. This study conducts a bibliometric analysis of ISWM research indexed in Scopus from 2015 to 2025. A total of 465 documents were retrieved using predefined search criteria. The data were cleaned and harmonized using Bibliomagika and OpenRefine, while VOSviewer was used to visualize bibliometric patterns. The results show that journal articles dominate the dataset, accounting for 55.70% of publications, followed by conference papers (20.22%) and book chapters (12.26%). English is the predominant publication language, representing 98.49% of the dataset, whereas Chinese and Korean each account for 0.43%, and German, Italian, and Persian each represent 0.22%. India records the highest publication output with 298 documents, followed by Indonesia (149) and Italy (98). Environmental Science is the leading subject area, accounting for 64.09% of publications, followed by Engineering (29.46%) and Energy (26.67%), with additional contributions from Social Sciences, Computer Science, Business, Economics, Agriculture, Chemistry, Medicine, and other fields. Keyword analysis identifies Waste Management as the most frequently occurring term (104 documents), followed by Sustainability (55 documents). These findings indicate that ISWM has evolved into an interdisciplinary field, with Environmental Science, Engineering, and Energy forming its primary knowledge base.

An Integrated Decision Support Framework for Demand Forecasting and Gypsum Inventory Optimization in Cement Manufacturing

2026-08-22T23:01:25+00:00

This study developed an integrated decision support framework that linked gypsum demand forecasting with the Economic Order Quantity (EOQ) and Periodic Order Quantity (POQ) inventory control methods. Historical gypsum consumption data from PT Lafarge Cement Indonesia for 2023–2024, together with ordering costs, holding costs, and replenishment lead times, were analyzed to develop an inventory planning strategy for 2025. Three forecasting methods quadratic, exponential, and cyclical forecasting were evaluated using Mean Absolute Percentage Error (MAPE), and the model with the lowest MAPE was selected to estimate future gypsum demand. The results showed that the selected cyclical forecasting method predicted an annual gypsum demand of 73,167.64 tons for 2025. Under the existing inventory policy, the total inventory cost was Rp6,475,551.63. The EOQ model yielded an optimal order quantity of 6,233 tons and a total inventory cost of Rp5,297,287.41, representing savings of Rp1,178,264.22, or 18.20%. The POQ model resulted in a replenishment interval of approximately 1.02 months, with a safety stock of 15,712.24 tons and a reorder point of 22,475.05 tons. This approach resulted in a total inventory cost of Rp5,239,614.91. Compared with the existing policy, the POQ model provided estimated savings of Rp1,235,936.72, equivalent to a 19.09% reduction in inventory costs. These findings demonstrated that integrating demand forecasting with EOQ and POQ provided a practical approach to improving gypsum inventory planning, reducing inventory costs, and maintaining material availability in cement manufacturing.

Analysis and Visualization of Global Research Trends in Sustainable Shrimp Farming Through Bibliometrics

2026-08-06T06:56:07+00:00

This study aimed to comprehensively examine global research trends in sustainable shrimp farming and identify research gaps that require further investigation. The analysis was based on 294 research articles published between 2014 and 2023 and indexed in the Scopus database. Using bibliometric methods and VOSviewer software, the study evaluated publication output, subject areas, journals, authors, keywords, countries, and other bibliometric indicators to assess the global development of research in this field over the study period. The field of sustainable shrimp farming expanded rapidly, with a continuous increase in the number of publications through 2023. India recorded the highest number of publications, with 47 articles. The most frequently occurring keywords included "Bacterium," "Carbon," "Crustacean," "Food Supplementation," "Immunity," "Microbiology," "Nonhuman," "Penaeus vannamei," "Probiotic," and "Vibrio." The bibliometric analysis provided valuable insights into the current status, research progress, and future potential of this field. Based on the findings, several promising directions for future research were identified: (1) the relationship between dietary supplementation and immune responses, including the interactions between probiotics and Vibrio; (2) the immune responses of shrimp species to Vibrio, carbon-related factors, and food supplementation; and (3) the influence of probiotics on the cultivation and health performance of Penaeus vannamei.

Environmentally Friendly Silver Nanoparticle Synthesis Using Gandaria (Bouea macrophylla) Leaf Waste Extract for Mercury Detection in Facial Cream Products

2026-08-06T06:56:09+00:00

This study aimed to synthesize and characterize silver nanoparticles (AgNPs) using the stem bark extract of Gandaria (Bouea macrophylla) and to evaluate their selectivity for mercury (Hg) detection. The Gandaria stem bark was extracted using methanol as the solvent through the maceration method. Silver nanoparticles were synthesized using extract concentrations of 1%, 2%, and 4%. Characterization of the AgNPs using UV–Visible spectrophotometry showed that the highest absorbance was observed at the 4% extract concentration, whereas the lowest absorbance was recorded at the 1% concentration. The selectivity test demonstrated that the synthesized AgNPs were highly selective toward Hg in HgCl₂ solution compared with Pb in PbCl₂ solution and Ca in CaCl₂ solution. AgNPs synthesized using the 4% extract concentration could be used as a preliminary qualitative colorimetric detection material for identifying mercury in facial whitening creams available on the market. Based on Particle Size Analyzer (PSA) and Scanning electron microscopy with energy dispersive X-ray spectrometry (SEM–EDX) analyses, the AgNPs synthesized using the 4% Gandaria stem bark extract were confirmed to fall within the nanoparticle size range.

Optimization Strategies for Waste Management in Wildlife Tourism Areas: A Systematic Literature Review

2026-08-06T06:56:09+00:00

Waste management in ecologically sensitive tourism areas has faced considerable challenges in balancing operational efficiency with environmental conservation. This study aimed to identify Solid Waste Management (SWM) optimization techniques that had been applied in tourism and conservation areas, evaluate their performance in supporting environmental sustainability, and analyze their respective strengths and limitations. The study employed a Systematic Literature Review (SLR) following the PRISMA guidelines. A total of 22 articles published between 2020 and 2026 were analyzed based on publication characteristics, study locations, optimization techniques, and their contributions to operational efficiency and habitat conservation. The review revealed that SWM optimization techniques had evolved from conventional mathematical approaches toward more integrated models through the adoption of artificial intelligence (AI), the Internet of Things (IoT), waste-to-energy technologies, and circular economy frameworks. Exact optimization models proved effective for cost minimization and transportation optimization, whereas AI and IoT supported real-time monitoring and decision-making. Waste-to-energy and circular economy approaches contributed most significantly to waste reduction, renewable energy generation, and resource recovery. Overall, the review concluded that hybrid optimization models integrating digital technologies, resource recovery, and collaborative governance represented the most promising approach for supporting efficient and sustainable waste management in wildlife conservation tourism areas.