The journal Serambi Engineering (JSE) was published by the Faculty of Engineering, Universitas Serambi Mekkah, Banda Aceh, with the first issue Vol. 1 No. August 1 - December 2016. Editorial receives of scientific article submissions from academics and practitioners either from Universitas Serambi Mekkah or external Universitas Serambi Mekkah. JSE has e-ISSN: 2528-3561 and p-ISSN: 2541-1934
Faculty of Engineering, Universitas Serambi Mekkah
Pengaruh Diversifikasi Produk terhadap Profitabilitas dan Efisiensi Usaha Mikro di Sektor Perikanan
Product diversification is a crucial strategy for micro enterprises in the fisheries sector to enhance profitability, efficiency, and business sustainability. Heavy reliance on selling fresh fish often leads to unstable income among fishermen and fish processors due to price fluctuations and perishability risks. This study aims to analyze the impact of product diversification on the profitability and efficiency of micro-scale fisheries enterprises using a Systematic Literature Review (SLR) approach. The analysis was conducted by reviewing literature from international sources such as FAO, UNEP, UNIDO, and OECD, as well as empirical studies on innovation, operational efficiency, and fishery waste management. The findings indicate that product diversification can increase income by 20–40%, expand market reach, reduce raw material waste, and create a more efficient and environmentally friendly production system. Moreover, diversification generates significant socio-economic impacts, including new employment opportunities, enhanced skills among coastal communities, and improved competitiveness of local products in modern markets. However, the success of diversification largely depends on access to finance, technical skills, and market connectivity. Therefore, collaboration between entrepreneurs, government, cooperatives, and financial institutions is essential to achieve sustainable product diversification in the fisheries sector.
Product diversification, micro fisheries enterprises, profitability, operational efficiency, economic sustainability
Copyright (c) 2025 Radhiana , Sufitrayanti , Nurfiani Syamsuddin, Cut Rusmina (Author); Teuku Kaifasyah (Translator) https://creativecommons.org/licenses/by/4.0
Efisiensi Produksi melalui Otomatisasi Sederhana Pada Industri Kerajinan Skala Rumah
This study aims to analyze the implementation of simple automation as a strategy to enhance production efficiency in small-scale home craft industries. In an increasingly competitive creative economy, small business owners are required to improve productivity without investing heavily in advanced technology. This research employs a descriptive qualitative approach using the Systematic Literature Review (SLR) method to identify relevant forms of simple automation, including semi-mechanical tools, time-based work systems, and ergonomic production layouts. The results indicate that simple automation can increase work efficiency, reduce human error rates, and lower production costs by approximately 25-40% without compromising product quality. Furthermore, the adoption of simple automated systems positively impacts production stability and competitiveness in household craft enterprises. This study contributes to practical insights for micro and small entrepreneurs as well as policymakers in developing sustainable efficiency strategies through affordable and context-appropriate technological innovation
Production efficiency, simple automation, craft industry, SMEs, technological innovation
Copyright (c) 2025 Ijal Fahmi, Cut Rusmina, Nelly , Maryam (Author); Reza Mustafa (Translator) https://creativecommons.org/licenses/by/4.0
Optimalisasi Efisiensi Operasional Melalui Inovasi Proses di Industri Daur Ulang Plastik UMKM
This article examines the role of process innovation in improving operational efficiency within the plastic recycling industry, particularly among small and medium enterprises (SMEs). Operational efficiency serves as a key factor in ensuring both sustainability and profitability amid growing environmental concerns and the global shift toward a circular economy. Through an extensive literature review of international sources, this study highlights how the adoption of technologies such as sensor-based automatic sorting systems, energy-efficient washing, the Internet of Things (IoT), and supply chain digitalization can reduce production costs, enhance product quality, and increase production capacity. However, findings also indicate that several challenges persist, including limited investment capital, low technological literacy, infrastructural disparities, and regulatory uncertainty. Therefore, the success of process innovation in the recycling industry depends heavily on collaborative support from governments, research institutions, industry associations, and NGOs. This paper contributes both theoretically and practically by proposing a conceptual framework that links process innovation, operational efficiency, and sustainability, serving as a foundation for strengthening SMEs toward an inclusive and competitive green industry
Process innovation, operational efficiency, plastic recycling, SMEs, circular economy
Copyright (c) 2025 Rahmi, Mahdi, Syaifuddin Yana, Jen Surya (Author); Alfian Nurhadi (Translator) https://creativecommons.org/licenses/by/4.0
Analisis Manajemen Risiko Finansial pada Startup Pengolahan Limbah Plastik Berbasis Inovasi
Innovative plastic waste recycling startups play a crucial role in promoting the circular economy and sustainable development. However, this sector faces various complex financial risks, including high initial investment requirements, market fluctuations, liquidity constraints, and regulatory uncertainty. This article aims to analyze the main categories of financial risks faced by plastic recycling startups and identify effective mitigation strategies based on recent literature reviews. Using a qualitative approach through an extensive review of international sources such as OECD, UNIDO, and IFC, the study reveals that initial investment and liquidity risks have the highest probability and impact on business sustainability. Effective mitigation strategies include funding diversification (via venture capital, green crowdfunding, and green financing), technology-based operational efficiency, and the implementation of digital cash management systems. Furthermore, external actors particularly governments, financial institutions, research bodies, and NGOs play a significant role in strengthening startups’ financial resilience through regulation, financing, innovation, and advocacy support. This study highlights the importance of integrating technological innovation with financial risk management as a foundation for sustainable eco-friendly startups while addressing the existing research gap on financial risk management in the recycling sector of developing countries
Risk management, startup, plastic waste, circular economy, green financing
Copyright (c) 2025 Maryam, Rita Nengsih, Filia Hanum, Khairuna (Author); Ajrina Humaira (Translator) https://creativecommons.org/licenses/by/4.0
Design of Waste Collection Sites at President University Campus: The Principles of Reduce, Reuse, Recycle (3R)
Waste management is a critical issue in Indonesia, where most of the waste produced is still not separated for disposal and handled properly. Despite having separate waste bins, President University has not consistently implemented waste separation, making it an appropriate case study for designing a 3R-based Temporary Waste Storage Site. This study aims to calculate the volume of existing waste and design a user-friendly 3R Temporary Waste Storage Site that supports the principles of Reduce, Reuse, and Recycle on campus. This study uses a mixed methods approach, combining direct observation and measurement of waste volume in Buildings A and B for eight consecutive days in accordance with SNI 3964:2025, as well as a questionnaire survey to assess students perception, behaviors, norms, and responsibility regarding waste management. The results show that the average waste production on campus is 79.75 kg/day, dominated by inorganic waste such as plastic bottles (17.5%) and plastic food containers (16.6%), followed by paper, cardboard, and organic food waste. The proposed technical design includes separate organic, inorganic, and residual waste facilities, composting using bamboo aerators, and leachate reservoirs. This design meets Indonesian regulatory requirements, with increased sorting and processing capacity. Social analysis using multiple linear regression revealed that perception significantly influenced student responsibility in waste management (p = 0.001), while behavior and norms showed weaker effects.
Waste management, President University, Design Temporary Waste Storage Site 3R.
Copyright (c) 2025 Inna Stephanie (Author) https://creativecommons.org/licenses/by/4.0
The Impact of Rainfall Fluctuations on the Trophic of Maninjau Lake Based on the Carlson Index and The Comprehensive Index (CTSI)
Maninjau Lake is experiencing increased eutrophication levels, negatively impacting water quality and the balance of its aquatic ecosystems. One of the factors that is thought to play a role in accelerating the process is rainfall fluctuation, which affects nutrient input from the water catchment area. This study aims to analyze the effect of rainfall fluctuation on the trophic status of Maninjau Lake using the Carlson Trophic State Index (TSI) and Comprehensive Trophic State Index (CTSI) methods. Water sampling was conducted at 10 stations over three periods: September 2022, January 2023, and March 2023, which represented seasonal variations. The parameters measured included chlorophyll-a, total phosphorus (TP), total nitrogen (TN), chemical oxygen demand (COD), and Secchi depth according to national standards. Rainfall data were obtained from BMKG stations and correlated with trophic index values. Results showed TSI values ranged from 55–72 and CTSI between 60–75, indicating eutrophic to hypereutrophic conditions. The highest trophic status occurred in periods of high rainfall, with a strong positive correlation between rainfall intensity and nutrient increase (r = 0.999 for TSI; r = 0.989 for CTSI). Rainfall plays a role as the main hydrometeorological driver of trophic dynamics, so adaptive management is needed to mitigate the impact of eutrophication under climate variability.
Copyright (c) 2025 Lia Arlina, Puti Sri Komala, Shinta Silvia (Author) https://creativecommons.org/licenses/by/4.0
Pemanfaatan Limbah Tambak Garam Sebagai Koagulan Bittern Untuk Menurunkan Parameter Kekeruhan Pada Limbah Tahu
The tofu industry produces wastewater with high turbidity, requiring treatment before being discharged into the environment. This study aims to utilize bittern, a byproduct of salt pond production, as an environmentally friendly alternative coagulant to reduce turbidity in tofu wastewater. Bittern was activated using three types of strong bases Ca(OH)₂, KOH, and NaOH with dosage variations of 40,50,60 mL and concentrations of 4%,6%,8%. The results showed that all activators enhanced the coagulation performance of bittern, with varying effectiveness under each treatment. NaOH provided the best result at a dosage of 50 mL and a concentration of 4%, achieving a turbidity removal efficiency of 95%. KOH reached optimal performance at 50 mL and 6%, with a turbidity removal efficiency of 93%, while Ca(OH)₂ achieved 85% efficiency at 50 mL and 6%. Overall, this study demonstrates that NaOH-activated bittern is an effective alternative coagulant with potential for sustainable application in tofu wastewater treatment.
Copyright (c) 2025 Pedro Caesariano, Muhammad Abdus Salam Jawwad (Author) https://creativecommons.org/licenses/by/4.0
Pengaruh pH Tanah Terhadap Metode Aerasi Dalam Stabilisasi Logam Berat Timbal (Pb2+)
This study examines the effect of soil pH variation on the effectiveness of the aeration method in stabilizing the heavy metal lead (Pb2+). Lead contamination from industrial waste and fossil fuels is a serious environmental problem as it is carcinogenic and can pollute ecosystems, including plants, posing a health risk to humans. Soil remediation is needed to address this issue, and soil aeration is one promising method. However, the effectiveness of aeration is highly influenced by soil environmental conditions, particularly pH, as low pH makes heavy metals easily soluble and mobile. This quantitative experimental study used 3 reactors with variations in pH treatment (acidic pH 4, neutral pH 6.5, and alkaline pH 10) and aeration duration (6 hours/day). Samples were analyzed using Atomic Absorption Spectrophotometry (AAS) to measure the remaining lead concentration, and the stabilization efficiency was calculated from the difference in concentration before and after treatment. The results showed that the alkaline pH treatment (pH 10) consistently provided the highest lead reduction efficiency, reaching 78.7% at a 24-hour aeration duration. Increasing the pH caused the Pb2+ ions to precipitate into insoluble and less toxic compounds. Statistical analysis using ANOVA confirmed that pH and aeration duration had a significant effect on the efficiency of lead (Pb2+) reduction.
Copyright (c) 2025 Moch Shafansyah Yumna Argia, Muhammad Abdus Salam Jawwad (Author) https://creativecommons.org/licenses/by/4.0
Pengaruh Penambahan Pasir Pada Metode Aerasi Tanah Dalam Stabilisasi Timbal (Pb)
Soil contamination by heavy metals, particularly lead (Pb), is a serious environmental issue in Indonesia, as it affects human health, ecosystems, and land productivity. Pb can accumulate in plants and enter the food chain, increasing public health risks. Therefore, an effective, low-cost, and field-applicable remediation method is required. One potential approach is aeration, which involves oxygen addition to improve soil porosity and enhance heavy metal stabilization. However, the effectiveness of aeration is strongly influenced by soil physical properties; hence, this study focuses on the effect of soil–sand composition on Pb stabilization in Inceptisol soil. The research was conducted using a laboratory-scale batch reactor with Inceptisol soil contaminated by Pb(NO₃)₂ (300 mg/kg). Treatments included three soil–sand ratios (100:0, 70:30, and 60:40) and three aeration durations (non-aerated, 12 hours, and 24 hours). Parameters analyzed were residual Pb²⁺ concentration and soil physical characteristics, with data processed using two-way ANOVA. Results showed that sand addition improved aeration effectiveness, achieving the highest Pb removal (94,6%; final Pb 17,1 mg/kg) at 60:40 composition with 24-hour aeration. In contrast, pure soil without aeration showed the lowest effectiveness (76,1%). Statistical tests confirmed that media composition, aeration duration, and their interaction significantly affected Pb stabilization (p < 0,05). This study demonstrates that combining aeration with sand addition offers a simple and practical method for remediating Pb-contaminated Inceptisol soil.
Copyright (c) 2025 Faiq Pandu Mahajana, Muhammad Abdus Salam Jawwad (Author) https://creativecommons.org/licenses/by/4.0
Iron Ball Launcher Platform Control System for Impact Test at Glass Testing Laboratory
This study presents the digital transformation of a glass impact test system at the Center for Standardization and Services for the Ceramic and Non-Metallic Mineral Industry (BBK) through Industry 4.0 integration. The legacy system faced challenges including manual distance measurement, outdated safety components, mechanical momentum causing positioning inaccuracy, and inability to sequentially launch multiple iron balls. To address these, a phased approach was implemented: analysis, design, implementation, and testing of a digital control system. Key upgrades included LIDAR-based wireless distance sensing (up to 9 meters), RS-485 communication for reliable data transfer, replacement of 1980s-era fuses with modern Mini Circuit Breakers, and algorithmic compensation for mechanical delay. A microcontroller-based control system enabled automated height adjustment, mode selection per national standards, and sequential ball release. The system was tested across six height settings with five trials each, achieving an error rate below 1% in all cases. Results confirm enhanced precision, safety, and efficiency. This targeted digitalization demonstrates how Industry 4.0 technologies can modernize legacy testing equipment without full replacement, offering a cost-effective, scalable model for industrial laboratories undergoing digital transformation.
Copyright (c) 2025 Iwan Awaludin, Muhammad Rizqi Sholahuddin, Yudi Widhiyasana, Sofy Fitriani (Author) https://creativecommons.org/licenses/by/4.0
Penambahan Magnesium Oksida (MgO) Terhadap Sifat Sintesis Hidroksiapatit Berpori
Hydroxyapatite (HAp) is a bioceramic material widely used in the medical field, especially as a bone filler for bone tissue regeneration. However, pure HAp has low mechanical strength so that material modification is required. This study aims to examine the effect of the addition of Magnesium Oxide (MgO) and Polyvinyl Alcohol (PVA) on the morphological characteristics, functional groups, pore size, porosity, and Ca/P content of porous hydroxyapatite synthesized by the precipitation method. Variations in the weight percentage of MgO (14–18% wt) and the ratio of distilled water and Polyvinyl Alcohol (PVA) solution (20–60%) were used in the preparation of porous hydroxyapatite. Characterization includes spectrophotometric tests to analyze Ca/P content, morphological tests using SEM, functional group analysis using FTIR, and surface area analysis using BET. Based on the results of the test analysis that has been carried out, it is known that the porous hydroxyapatite sample with a variation of 1,8% MgO addition and 40% PVA ratio has a Ca/P value of 1,67 and has good characteristics for biomaterial applications with a granular morphological structure surface area of ​​7.3849 m2/g with an average pore size of 2.0274 nm, and is not toxic to health.
Copyright (c) 2025 Firmansyah Sophian Putra (Author) https://creativecommons.org/licenses/by/4.0
Evaluasi Sistem Drainase Kelurahan Sudajaya Hilir, Kecamatan Baros, Kota Sukabumi
Sudajaya Hilir Village, Baros District, Sukabumi City, is one of the areas prone to flooding due to drainage capacity and land use changes. This study aims to evaluate the condition of existing channels and analyze their capacity using the EPA Storm Water Management Model (SWMM). The data used includes field surveys on the dimensions and condition of the channels, historical rainfall data, and drainage planning documents from the Sukabumi City Public Works and Spatial Planning Agency. The evaluation results show that the dimensions of the existing channels are not in accordance with the plan. The SWMM simulation identified points 1 to 5 along Jalan Lingkar Selatan. The difference in size between points 1 and 5 ranged from 0.05 to 0.20 meters. The SWMM simulation identified points 4 and 5 as having low elevations. Based on the simulation results, recalculations were performed to reduce the potential for flooding in the area. The recommended measure is to increase the width of the drainage channel at points 1 to the outfall by 0.1 to 0.4 meters. In addition, the construction of a retention pond at locations with lower elevations is also recommended to accommodate excess water discharge. With a combination of channel dimension improvements and the provision of retention ponds, the capacity of the drainage system is expected to increase, thereby reducing the risk of flooding more effectively.
Copyright (c) 2025 Eka Wardhani, Anggia Bagya Trirahmani (Author) https://creativecommons.org/licenses/by/4.0
Analisis Kinerja Membran PVC-TiO2 dengan Variasi Waktu dan Tekanan Operasi dalam Mereduksi TDS, Kekeruhan, dan Total Coliform pada Sungai Jagir
The Jagir River has experienced a decline in water quality due to domestic and industrial activities, with pollutant parameters such as TDS, turbidity, and total coliform exceeding the quality standards. This study aims to analyze the effect of operating time and pressure variations of PVC- TiO2 ultrafiltration membranes on the removal capability of TDS, turbidity, and total coliform parameters as well as the flux rate of the membrane. The addition of TiO2 aims to increase the flux rate of the UF membrane. This research method involves adsorption pre-treatment using granular activated carbon (GAC) before the ultrafiltration process with varying pressures (1; 1.5; 2 bar) and operating time (15 – 75 minutes). The results showed that adsorption pre-treatment was able to reduce turbidity (95.45%), total coliform (59.93%), and TDS (18.89%). The combination of 2 bar pressure with an operating duration of 75 minutes resulted in the highest removal efficiency for all three parameters, namely total coliform (100%), turbidity (96.90%), and TDS (18.84%). TiO2 coating increases the membrane flux rate at the start of operation, especially at high pressures, but over time it decreases drastically due to fouling.
Copyright (c) 2025 Della Putri Adjani, Restu Hikmah Ayu Murti (Author) https://creativecommons.org/licenses/by/4.0
Efektivitas Biofilter dengan Media Papan Pakis dan Sistem Aerasi Intermittent dalam Mengurangi COD dan NH3-N pada Limbah Cair Rumah Potong Ayam
Wastewater generated from poultry slaughterhouses generally contains high levels of organic matter and ammonia, which can contaminate aquatic environments if not properly treated. The high organic content contributes to elevated COD levels, while ammonia can be toxic to aquatic organisms. This study was conducted to evaluate the performance of a biofilter system with intermittent aeration (anoxic–oxic combination) using tree fern board and bioring media in reducing COD and NH₃-N concentrations. The tested aeration durations included 3 hours (1 hour anoxic, 2 hours oxic), 6 hours (2 hours anoxic, 4 hours oxic), 9 hours (3 hours anoxic, 6 hours oxic), and 12 hours (4 hours anoxic, 8 hours oxic). The experimental results showed that the bioring medium exhibited better performance than the tree fern board, with the optimum condition achieved at a 12-hour hydraulic retention time, resulting in COD and NH₃-N reductions of 93.41% and 88.21%, respectively. Overall, the findings indicate that a bioring-based biofilter with intermittent aeration has strong potential as an effective and environmentally friendly alternative technology for treating poultry slaughterhouse wastewater.
aerasi intermittent, biofilter, COD, NH3-N, limbah cair rumah potong ayam
Copyright (c) 2025 Flaherti Maharani, Raden Kokoh Haryo Putro (Author) https://creativecommons.org/licenses/by/4.0
Implementasi Sistem Monitoring Kelembapan Tanah Berbasis Internet Of Things
Soil moisture monitoring is a crucial factor in precision agriculture, yet conventional methods often lack accuracy and efficiency. This research aims to design, implement, and evaluate an Internet of Things (IoT)-based soil moisture monitoring system with a focus on a comparative performance analysis of three different sensor types: the Capacitive Soil Moisture Sensor v1.2, the Soil Moisture Sensor FC-28 (resistive), and the Waterproof & Anti-Rust Sensor. The system was developed using an ESP32 microcontroller and the ThingSpeak platform for real-time data visualization. Tests were conducted on chili, tomato, and eggplant planting media, with data from each sensor validated against a digital soil tester as a ground truth instrument. Accuracy performance was quantitatively evaluated using the Mean Absolute Error (MAE) and Mean Absolute Percentage Error (MAPE) methods. The results demonstrate that the Capacitive Soil Moisture Sensor v1.2 provides the highest and most stable accuracy, recording the lowest error rates (MAE 6.4%; MAPE 7%). Conversely, the Soil Moisture Sensor FC-28 showed moderate performance with low stability, while the Waterproof & Anti-Rust Sensor exhibited the highest error rates (MAPE up to 46%). This study concludes that capacitive-based sensors are significantly superior and are recommended for implementing reliable and accurate IoT monitoring systems.
internet of things, soil moisture, capacitive sensor, resistive sensor, esp32
Copyright (c) 2025 Alwin Okta, Firmansyah (Author) https://creativecommons.org/licenses/by/4.0
Penerapan Lubang Resapan Biopori Dalam Meningkatkan Laju Infiltrasi di Desa Sungai Langka
The Sungai Langka Village area lacks drainage and has elevated roads, causing water to run off during rainfall and onto the roads and into people's yards. In these conditions, efforts will be made to utilise water runoff as an alternative water source. This study aims to determine the effect of infiltration in the application of biopori infiltration pit technology. This research was conducted using a quantitative approach. The data were processed using the Horton method and analysed descriptively. Infiltration data was collected in situ in the field. The data compared the infiltration rate before and after the application of biopori infiltration pits. The results showed that the infiltration rate was constant at 46 cm/hour, 44 cm/hour, 32 cm/hour, 36 cm/hour and 32 cm/hour before the application of biopori infiltration pits. Meanwhile, the infiltration rates after the application of biopore infiltration pits were 110 cm/hour, 78 cm/hour, 70 cm/hour, 104 cm/hour and 138 cm/hour. The aim of the study was to determine how increasing infiltration rates can reduce water runoff and increase groundwater reserves.
Copyright (c) 2025 Nadia Dhannov, Irhamni, Fajriharish Nur Awan, Mutiara Fajar, Nabila Putriyandri Alifa, Yuni Lisafitri, Sillak Hasiany (Author) https://creativecommons.org/licenses/by/4.0
Pemanfaatan Ranting Pruning Jati dan Serasah Daun Area Reklamasi PT Semen Indonesia (Persero) Tbk Pabrik Tuban Sebagai Bahan Bakar Alternatif Berkelanjutan
The cement industry is one of the sectors with high energy intensity and a significant contributor to greenhouse gas emissions. This study aims to evaluate the utilization of biomass waste in the form of teak pruning twigs and leaf litter from the post-mining reclamation area of PT Semen Indonesia (Persero) Tbk Tuban Plant as a sustainable alternative fuel. The methods used include the collection, natural drying, and shredding of biomass to a size of less than 2 cm, which is then used as a partial substitute for coal in the kiln combustion process. The results show that this innovation successfully reduced heat energy consumption by 1008 GJ, saved operational costs of IDR 32,800,913, and reduced carbon emissions by approximately CO2 96.728 tons of CO2 from January 2024 to June 2025. This program not only improved energy efficiency and environmental performance but also transformed the value chain into a more collaborative and sustainable one, supporting the principles of the circular economy.
Copyright (c) 2025 Agus Setyo Budi, Arthur Hajar Hantoro, Agrifa Tarigan, Moch. Khalik Hermawanto (Author) https://creativecommons.org/licenses/by/4.0
Evaluasi Sifat Mekanik Lentur Beton Menggunakan Serat Abaka dan Substitusi Abu Cangkang Tiram
Flexural strength is one of the mechanical properties of concrete that is often overlooked in achieving maximum concrete performance. Abaca fiber, a natural fiber, has been widely used to enhance the flexural strength of concrete. However, its utilization remains limited and has never been combined with Oyster Shell Ash (OSA). Therefore, this study aims to determine the density, slump flow, and flexural strength of high-strength concrete with a 5% substitution of OSA, supplemented with 2% superplasticizer and abaca fiber at proportions of 0.15%, 0.30%, and 0.45%, with curing for 28 days. The oyster shells were sourced from Surien, Meuraxa District, Banda Aceh City, while the abaca fibers were obtained from East Java. The experimental design followed the ACI 211.4R-93 (American Concrete Institute) method. The results showed that an excessive addition of abaca fiber reduces the density of concrete. Incorporating 0.15% abaca fiber increases the flexural strength of concrete. The combination of 5% OSA substitution with abaca fiber further improves flexural strength.
Copyright (c) 2025 Muhammad Iqbal, Bunyamin , Heru Pramanda, Rafiqa Muhnita Yusputri (Author) https://creativecommons.org/licenses/by/4.0
Tinjauan Kuat Tarik Belah Beton Menggunakan Bahan Substitusi Serat Roving dan Cangkang Tiram
Additives such as fibres have been widely used to increase the tensile strength of concrete. Previous research has shown that the tensile strength of concrete may also be increased by replacing 10% of the cement with waste materials, such as oyster shell ash. In this research, waste material in the form of oyster shells was combined with roving fibre (gypsum fibre). The objective in this research is to ensure the split tensile strength of concrete using 10% oyster shell waste combined with 5%, 10% and 15% gypsum fibre in cement. The oyster shell waste was sourced from Krueng Neng, Aceh Besar. Gypsum fibre was sourced from a building materials shop in Banda Aceh City. This research used the method of ACI 211.1-91 or American Concrete Institute and ASTM or American Society for Testing and Materials, with cylindrical test specimens (15 cm x 30 cm). The test results showed that the normal splitting tensile strength of concrete was 2.95 MPa. Meanwhile, the splitting tensile strengths of concrete with gypsum fibre and oyster shell ashsubstitution were 3.10 MPa, 3.49 MPa and 3.51 MPa. The combination of oyster shell ash and gypsum fibre in concrete can significantly increase the splitting tensile strength of concrete.
Kaitan Penggunaan Antibiotik pada Kegiatan Antropogenik terhadap Pencemaran Antibiotic Resistance Escherichia coli di Sungai Citarum Hulu
The discovery of antibiotics has provided significant benefits to the world of medicine and human health. Their ability to prevent the growth and even kill pathogenic bacteria has led to their widespread use in various anthropogenic activities, such as livestock farming and healthcare facilities. However, the irrational use of antibiotics has led to the emergence of Antibiotic Resistance Escherichia coli (AREc), which exhibits resistance to antibiotics. This is caused by environmental contamination from antibiotic residues. In addition to livestock farming and healthcare facilities, other anthropogenic activities contributing to antibiotic residue contamination include the manufacturing process of antibiotics in the pharmaceutical industry. It is necessary to determine the correlation between anthropogenic activities and the abundance of AREc in the environment. A causal relationship was found between the use of various types of antibiotics in anthropogenic activities and the resistance properties of AREc detected in some of the samples obtained. This causal relationship indicates the role of antibiotic use in AREc pollution occurring in the Upper Citarum River. Additionally, anthropogenic activities that significantly contribute to AREc pollution in the Upper Citarum River are healthcare facilities, which are correlated with high antibiotic use in such activities. A strong relationship was also found between the total Escherichia coli group and AREc erythromycin with dissolved oxygen in the Upper Citarum River.
Copyright (c) 2025 Rifky Rizkullah Fahmi, Siska Widya Dewi Kusumah, Herto Dwi Ariesyady (Author) https://creativecommons.org/licenses/by/4.0
Pengaruh Intensitas Cahaya dan Kecepatan Pengadukan Terhadap Degradasi Limbah Laundry Menggunakan Fotokatalis ZnO-Zeolit dari Limbah Baterai Zn-C
Wastewater from laundry activities contains various pollutants such as phosphates, surfactants, and dyes that can harm the environment. This study proposes an innovative solution by utilizing waste from Zn-C batteries as a raw material for synthesizing ZnO photocatalysts. Photocatalysis is an effective method for degrading pollutants, and using ZnO from battery waste provides a more economical and sustainable alternative. To enhance photocatalytic performance, ZnO is combined with zeolite as a supporting material to modify its electronic structure, especially to lower the band gap energy, thereby increasing its ability to break down harmful compounds in laundry wastewater. The ZnO-Zeolite photocatalyst was tested using 0.75 grams of catalyst with 100 mL of laundry wastewater for 60 minutes. Variations in stirring speed (200–800 rpm) and UV lamp intensity (15 Watt, 20 Watt, and without UV) were applied. Photocatalytic performance was evaluated by measuring pH, COD, and TSS after the degradation process. The best performance was obtained at 20 Watt UV light and 600 rpm stirring speed, resulting in COD of 60 mg/L, TSS of 31 mg/L, and pH 6.62. Lower efficiency at higher stirring speeds occurred due to excessive turbulence, causing particles to resuspend and reducing degradation effectiveness.
Photocatalysis, ZnO, Zeolite, Laundry Wastewater, Zn-C Battery Waste, Photodegradation, Stirring Speed, Light Intensity
Copyright (c) 2025 Sherly Fitria Novita, Asri Safira, Yuniar, Tahdid, Erika Dwi Oktaviani (Author) https://creativecommons.org/licenses/by/4.0
Analisa Intensitas Konsumsi Energi dan Sistem Pencahayaan pada Gedung Teknik Kimia Universitas Malikussaleh
Energy audits are a crucial step in energy management, providing an indication of a building's energy efficiency. This study, conducted in the Chemical Engineering Building at Malikussaleh University, aimed to evaluate electrical energy consumption by calculating energy consumption intensity (EKE), and to verify compliance with the 2020 Indonesian National Standards (SNI) for the lighting system. Data were collected through direct observation, interviews, and the analysis of documentation. The study focused on analysing lighting levels and electrical energy consumption, including calculating IKE. The results showed that lighting levels in most rooms did not meet SNI standards, with only the terrace area meeting the criteria. The building's daily energy consumption was found to be 402.8 kWh, with cooling loads accounting for the largest proportion. The IKE values for lighting and cooling on both floors of the building were below the required standard, indicating a lack of energy efficiency. The main factors influencing these results were inadequate lighting design, the use of inappropriate lamp types, and suboptimal maintenance of the lighting system. To improve energy efficiency, it is recommended that lamps are added or replaced with high-efficiency ones and that energy planning is improved based on a more comprehensive energy audit. This research contributes to improving energy efficiency in the education sector.
Audits, Energy. IKE, Light system, SNI 2020.
Copyright (c) 2025 Teuku Multazam, Beni Maidika, Andik Bintoro (Author) https://creativecommons.org/licenses/by/4.0
Efektivitas Free Floating Wetland Tanaman Kiambang (Salvinia Molesta) Dengan Penambahan EM4 Dalam Pengolahan Limbah Laundry Pada Kondisi Anoxic–Oxic
Laundry wastewater contains organic matter and detergents that have the potential to pollute the environment if not properly treated. One environmentally friendly method to address this problem is the free floating wetland (FFW) system, which utilizes aquatic plants and microorganisms. This study aimed to evaluate the effectiveness of water lettuce (Salvinia molesta) combined with 5% Effective Microorganisms 4 (EM4) in reducing Chemical Oxygen Demand (COD) and surfactants, as well as increasing Dissolved Oxygen (DO) levels in laundry wastewater. The experimental design consisted of two treatments: FFW with and without EM4 addition, over a 5-day retention time divided into an anoxic phase (day 0 to day 2) and an oxic phase (day 3 to day 5). The results showed that the combination of water lettuce and 5% EM4 was able to reduce COD by up to 80.9% and surfactants by 65%, while increasing DO to 5.02 mg/L. This success is attributed to the root system of the water lettuce, which enhances oxygenation in the rhizosphere zone, thus supporting the growth and activity of aerobic microorganisms. FFW based on water lettuce with EM4 addition has the potential to be an effective, sustainable, and environmentally friendly laundry wastewater treatment technology.
COD, DO, EM4, Free Floating Wetland, Kiambang, Limbah Laundry, Surfaktan
Copyright (c) 2025 Icha Ayoe Bilbina, Mohamad Mirwan (Author) https://creativecommons.org/licenses/by/4.0
Optimalisasi Produksi Biogas Melalui Penambahan Trace metals (Mo dan Zn) dengan Pemanfaatan Kotoran Sapi, Eceng Gondok (Eichhornia Crassipes) dan Sampah Organik pada Digester Batch Reactor
Biogas production is now a practical solution to deal with organic waste while providing an environmentally friendly alternative energy source. This study was conducted to optimize biogas production by adding trace metals, namely molybdenum (Mo) and zinc (Zn), to a mixture of water hyacinth, fruit waste, and cow dung. The anaerobic fermentation process took place in a batch reactor for 35 days with four treatments: control without metals, addition of Mo 5 mg/kg, Zn 5 mg/kg, and a combination of Mo+Zn at 2.5 mg/kg each. Various parameters were measured, such as biogas volume and pressure, methane content (CH₄), carbon to nitrogen ratio (C/N), pH, temperature, and flame duration.The results showed that the addition of trace metals, especially the combination of Mo and Zn, significantly increased the amount and quality of biogas produced. The highest biogas volume was obtained in the treatment with Zn, while the best methane content appeared in the Mo+Zn combination. In addition, these trace metals help maintain pH stability and accelerate the active phase of fermentation. An ideal C/N ratio also supports the efficiency of methane production. In other words, the addition of these micro-nutrients strengthens the work of methanogenic bacteria and accelerates the conversion of organic matter into renewable energy.
Copyright (c) 2025 Naufal Arhab, Mohamad Mirwan, M. Abdus Salam Jawwad, Maroeto (Author) https://creativecommons.org/licenses/by/4.0
Pemilihan IPAL Grey Water di Rumah Deret Tamansari Kota Bandung
The Tamansari Row Houses in Bandung City are part of a relocation and slum revitalization program aimed at providing more organized, healthy, and decent housing for affected communities. Currently, the facility does not have a grey water treatment system. Grey water generated from bathing, laundry, and kitchen activities contains harmful pollutants that could contaminate the Cikapundung River if discharged directly. Therefore, it is necessary to design a grey water treatment plant (WWTP) with the potential reuse of the treated effluent for plant irrigation. The peak grey water flow rate was calculated at 144.872 m³/day, representing 70% of the peak domestic wastewater flow. Grey water characteristics showed a pH of 7.83; BOD of 46.60 mg/L; COD of 134.66 mg/L; TSS of 46 mg/L; oil and grease of 4 mg/L; ammonia of 6.28 mg/L; and total coliform of 8,400 counts/100 mL. The selection of the treatment alternative was carried out using descriptive analysis and the Weighted Ranking Technique (WRT). The selected treatment train consists of an oil and grease separator, Anaerobic Baffled Reactor (ABR), disinfection unit, and storage tank.
WWTP, Grey Water, Row Houses, Characteristics, and WRT Method
Copyright (c) 2025 Eka Wardhani, Muhammad Syauqi Rahman, Yulianti Pratama, Kancitra Pharmawati (Author) https://creativecommons.org/licenses/by/4.0
Sintesis dan Karakterisasi Biodegradable Styrofoam Berbahan Dasar Tepung Singkong dan Selulosa Batang Singkong dengan Metode Thermopressing
Environmental concerns arising from the accumulation of synthetic styrofoam waste have prompted the search for eco-friendly packaging alternatives. This study aims to synthesize and characterize biodegradable styrofoam made from cassava flour and cellulose extracted from cassava stems using the thermopressing method. Cellulose was obtained through delignification and bleaching of dried cassava stems sieved to 80 mesh. The synthesis process involved varying polyvinyl alcohol (PVA) concentrations (0–20% w/w) and molding temperatures (140–180°C). Characterization included water absorption, soil burial biodegradation, and tensile strength testing. The results showed that increasing PVA concentration and molding temperature reduced water absorption and improved tensile strength. The optimal formulation was achieved with 20% PVA and a pressing temperature of 180°C, resulting in 8.41% water absorption, 30.33% biodegradation after 30 days, and a tensile strength of 2.88 MPa. Although the tensile strength does not yet meet the Indonesian National Standard (SNI ≥29.16 MPa), the material demonstrates promising potential as a biodegradable alternative to petroleum-based styrofoam.
biodegradable styrofoam, cassava flour, cassava stem cellulose, thermopressing, pva, characterization
Copyright (c) 2025 Mochammad Rasyiid Febrianto, Laily Tazkiyah, Dyah Suci Perwitasari (Author) https://creativecommons.org/licenses/by/4.0
Analisis Life Cycle Assessment Produksi Biokoagulan Cangkang Maggot
Black soldier fly shell as biocoagulant is considered effective in removing pollutants, making it a potential alternative coagulant in the coagulation-flocculation process. However, studies on the environmental impact of natural coagulant production need to be conducted as an assessment of the sustainability of natural coagulants. This study aims to analyze the environmental impacts caused by the production of black soldier fly shell biocoagulant using Life Cycle Assessment (LCA) with the ReCiPe 2016 method through Midpoint and Endpoint approaches using the SimaPro 9.6.0.1 software. The Life Cycle Assessment (LCA) was conducted with a gate-to-gate system boundary and a functional unit of 0.1 kg of raw biocoagulant material. Based on the results, the Midpoint approach showed the largest impact category as human carcinogenic toxicity with a total score of 1.07. Additionally, the Endpoint approach identified the largest impact category as human health with a total score of 20.7 Pt. The biggest contributor to the environmental impact in the production of black soldier fly shell biocoagulant is the chitosan dissolution stage, amounting to 5.11 Pt from the total human health impact. This is caused by electricity use, which affects human health.
Copyright (c) 2025 Marshanda Afifa Shalsabila, Euis Nurul Hidayah (Author) https://creativecommons.org/licenses/by/4.0
Komparasi Kinerja Membran Ultrafiltrasi Polyvinylidene Fluoride dan Polivinyl Chloride Pada Air Sungai Jagir dalam Menurunkan TDS
This study aimed to evaluate the performance of PVDF and PVC ultrafiltration membranes coated with Al2O3 in removing total dissolved solids (TDS) from Sungai Jagir river water after a pre-treatment adsorption using Granular Activated Carbon (GAC). The adsorption process was conducted for 10 minutes before the water was filtered through the membranes under various operating pressures (1, 1.5, and 2 bar) and operation times (0.1–0.5 h). The results showed that both membranes exhibited an increase in TDS rejection efficiency with longer operation time, while pressure had a limited effect. The PVDF membrane demonstrated consistently higher TDS rejection compared to PVC, suggesting that membrane surface properties influence solute removal efficiency. Statistical analysis using three-way ANOVA revealed that operation time had a significant effect on TDS rejection, whereas pressure did not show a notable impact. These findings indicate that contact duration between water and membrane plays a crucial role in reducing TDS in river water through ultrafiltration.
Copyright (c) 2025 Shafa'ul Mufidah, Restu Hikmah Ayu Murti (Author) https://creativecommons.org/licenses/by/4.0
Pemanfaatan Limbah Kotoran Sapi dan Molase Kulit Pisang Sebagai Efektifitas Produksi Biogas di Desa Daeo Kabupaten Pulau Morotai
The community's dependence on kerosene remains a major issue, especially in disadvantaged, frontier, and outermost (3T) areas such as Morotai Island Regency. This study focuses on the utilisation of fresh cow dung waste combined with banana peel molasses as raw materials for biogas production. The research methods used were quantitative descriptive and experimental with trials on three digester designs. Based on the results of the study, the three digester designs showed significant differences, where RD1 was less than optimal because the low pH (6) caused unstable CH₄ production, 0 psi pressure, (CO₂, CO = 0), RD2 was the best design with neutral pH (7), stable mesophilic temperature (25–31 °C), high pressure (34 psi), and consistent CH₄ production increasing to 10,100 ppm, while RD3 was still able to produce fairly high CH₄ (8,731 ppm) despite relatively acidic pH. Regression analysis shows that in RD1, pH greatly affects CH₄ (R² = 0.899), while in RD2 and RD3, temperature is the dominant factor (R² > 0.997) in increasing methane production. In general, neutral pH and mesophilic temperature conditions proved to be most conducive to methanogenic bacterial activity, with RD2 as the most optimal digester design producing high-quality biogas with a neutral pH of 7, temperature of 31°C and pressure of 34 psi, and CH₄ consistently increasing to 10,100 ppm.
Copyright (c) 2025 Muhammad Fahmi Aja, Hasrul Saleh, Siti Hanian Bilo (Author) https://creativecommons.org/licenses/by/4.0
Integrasi Lean DMAIC dan Circular Economy untuk Reduksi Waste pada Manufaktur Paving Block
Waste is a significant challenge in the manufacturing industry, including small and medium enterprises (SMEs) engaged in paving block production. This study applies the Lean DMAIC (Define–Measure–Analyse–Improve–Control) methodology to identify, analyze, and reduce waste in the production process. A case study was conducted at a paving block factory in East Java, which has an annual production capacity of 119,400 m². Data were collected from production records, observations, and interviews conducted between September 2024 and August 2025. Analysis using a weighted Pareto diagram and Flow Process Mapping revealed that defect categories, although accounting for only 1.99% of total production, resulted in a significant accumulation of dead stock in the storage area. Through a Decision Matrix and a radar chart, a recycling strategy was selected as the improvement solution. This strategy was subsequently formalized into a Standard Operating Procedure (SOP) for managing rejected products, ensuring consistent implementation and adherence. Evaluation of the implementation over one month showed a 23.8% reduction in dead stock volume. These findings provide empirical evidence of the effectiveness of integrating Lean DMAIC with circular economy principles in the paving block industry, offering a practical framework that can be replicated in similar manufacturing sectors.
Copyright (c) 2025 Dini Retnowati, Ahmad Fatih Fudhla, Asri Dwi Puspita, Sofia Annurrada (Author) https://creativecommons.org/licenses/by/4.0