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Contact Name
Mira Lestira Hariani
Contact Email
mira.hariani0103@ugj.ac.id
Phone
+6287718070807
Journal Mail Official
greenscience.ft@gmail.com
Editorial Address
Jl. Pemuda No.32, Kel. Sunyaragi, Kec. Kesambi Kota Cirebon 45132
Location
Kota cirebon,
Jawa barat
INDONESIA
Journal of Green Science and Technology
ISSN : 25981277     EISSN : 26213966     DOI : https://doi.org/10.33603/jgst.v9i1
Core Subject : Engineering,
Journal of Green Science and Technology (JGST) published since 2017 by Faculty of Engineering Universitas Swadaya Gunung Jati Cirebon, Indonesia with p-ISSN 2598-1277 and e-ISSN 2621-3966. JGST publishes twice a year in March and September. Publications before 2023 can be seen here. Journal of Green Science and Technology (JGST) has been accredited by National Journal Accreditation (ARJUNA) Managed by Ministry of Research, Technology, and Higher Education, Republic Indonesia since year 2022 to 2022 according to the decree No. 230/E/KPT/2022. Journal of Green Science and Technology (JGST) accepts and publishes multidisciplinary research and critical review of issues that contains of all scientific works related to the field of following Sciences Engineering: - Civil Engineering - Architectural Engineering - Environmental Engineering - Chemical Engineering - Mechanical Engineering - Electrical Engineering - Industrial Engineering - Informatics Engineering, etc. All manuscripts must be written in English.
Articles 142 Documents
Design of a Construction Project Risk Monitoring and Control Framework through a Synthesis of Literature and Practice Winandyani, Medina; Wiguna, I Putu Artama
Journal of Green Science and Technology Vol 10 No 1 (2026): Journal of Green Science and Technology Vol. 10 No.1 March 2026
Publisher : Faculty of Engineering, Universitas Swadaya Gunung Jati

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33603/jgst.v10i1.11820

Abstract

Construction projects operate under high uncertainty and remain vulnerable to cost, time, quality, and occupational safety issues. Although risk management is commonly applied, risk monitoring and control in practice often remain fragmented, with indicator tracking, follow-up actions, and reporting not always connected in a clear operational flow. This study aims to develop an initial design of a construction project risk monitoring and control framework that is practical, systematic, and easy to implement. The study adopts a design-study approach using secondary data derived from international standards and guidelines, scientific literature, and Indonesian construction risk management references, which were synthesized to identify the key process, information, and tool requirements of the framework. The proposed design integrates an iterative monitoring and control workflow, structured risk information including Early Warning Signs (EWS), Key Risk Indicator (KRI) grouping, metrics and thresholds, and action effectiveness evaluation, as well as semi-automated spreadsheet-based tools to support risk recording, evaluation, updating, and reporting. The contribution of this study lies in translating risk monitoring and control principles into a connected operational design that can support more consistent, traceable, and system-based project risk management practice. As a literature- and practice-based initial design, this framework is intended to serve as a foundation for further expert validation and implementation in construction projects.
Evaluation of Traffic Space Occupancy Levels Due To Illegal Parking in Urban Commercial Areas Hariani, Mira Lestira; Sugiyanto, Martinus Agus; Fatah, Abdullah; Abdurahman, Ryan; Kurniasih, Sari
Journal of Green Science and Technology Vol 10 No 1 (2026): Journal of Green Science and Technology Vol. 10 No.1 March 2026
Publisher : Faculty of Engineering, Universitas Swadaya Gunung Jati

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33603/jgst.v10i1.11969

Abstract

Illegal parking in urban commercial corridors is commonly treated as a public-order problem. From a spatial perspective, however, it also reflects a shift in roadway function, where traffic space is temporarily converted into static space. This study examines that shift using longitudinal occupation (OL), effective width reduction (EWR), and a proposed composite measurement approach termed the Space Pressure Index (SPI). The case site is an approximately 200 m urban commercial segment where vehicles routinely park in parallel on both sides despite the absence of formal parking facilities. Data were collected through a four-day parking patrol survey covering two weekdays and two weekend days, supported by roadway-width measurements under two-sided parking conditions. The results show a clear time-dependent pattern: parking builds up and intensifies during peak commercial hours. Longitudinal occupation peaked at 120.7%, meaning that the cumulative equivalent length of parked vehicles exceeded the usable segment length during the busiest period. At the same time, two-sided parking reduced the effective width by 36.7% relative to the initial geometric width. When these two dimensions are combined, the SPI reached a maximum of 44.3%, indicating substantial functional conversion of movement space during the peak interval. Overall, the findings frame illegal parking in commercial areas as a measurable form of space competition with direct operational implications for corridor mobility. Compared with partial occupancy measures, the proposed OL-EWR-SPI approach offers a clearer segment-scale description of how roadway space is reallocated over time.
Design Of a Feeding System with a Capacity Of 3 Tons/Hour at the Npk Plant to Improve Feeding Efficiency and Automation Tsuroyyaa, Zakiyyah; Christianti, Christianti; Trirahayu, Dhyna Analyes; Chamidy, Harita Nurwahyu
Journal of Green Science and Technology Vol 9 No 3 (2025): Journal of Green Science and Technology Vol. 9 No. 3 December 2025 Special Editio
Publisher : Faculty of Engineering, Universitas Swadaya Gunung Jati

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33603/jgst.v9i3.10549

Abstract

An NPK plant is a facility that produces NPK fertilizer through a manufacturing process specifically designed to create fertilizer with a special formulation. However, in the production process, the feeding of raw materials is still done manually, resulting in low productivity and high operational costs. Based on production performance tests conducted on September 15, 2024, the manual system only achieved an average of 1.34 tons/hour, or 47% of the production target of 3 tons/hour. Therefore, a transportation system is needed to transport the materials, given the limitations of human labor capacity in terms of material handling and employee safety. This study aims to design an automatic feeding system to maximize production capacity up to 3 tons per hour. The system design begins with analyzing losses due to low productivity of the manual system, analyzing factory requirements, designing the main components of the feeding system, such as the hopper, weigher, and conveyor belt, equipped with an on-off control-based system to ensure consistent raw material flow. Technical design was carried out through visualization using AutoCAD and Visio software, solid flow simulation using Altair EDEM software, and economic feasibility analysis by calculating the Return on Investment (ROI) and Payback Period (POT). The calculation results show that this feeding system has a ROI of 40.8% and a POT of 2.05 years, indicating that the designed system is economically viable for implementation.
Enhancement Of Salt Quality with Recrystallization Method from Crude Salt Raw Material on a Laboratory Scale Suryadi, Joko; Witcaksono, Saifa Haikal; Salsabila, Putri Widad; Andrijanto, Eko; Ferawati, Yohana Fransiska; Jayanti, Retno Dwi; Rinaldi, Kardian; Haryadi, Haryadi
Journal of Green Science and Technology Vol 9 No 3 (2025): Journal of Green Science and Technology Vol. 9 No. 3 December 2025 Special Editio
Publisher : Faculty of Engineering, Universitas Swadaya Gunung Jati

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33603/jgst.v9i3.10609

Abstract

Indonesia has significant maritime potential, particularly in salt production. However, national salt production has not yet met domestic demand, especially for industrial-grade salt, which requires a minimum NaCl content of 97%. Crude salt produced using traditional methods often contains only 88-94% NaCl and includes impurities such as Ca, Mg, and sulfate. This research aims to produce recrystallized salt that meets industrial standards and to determine the optimal conditions in a laboratory-scale simulator. The experimental method was conducted by simulating evaporation on a recrystallization table. Salt solutions were prepared from crude salt with varied concentrations of 22%, 25%, and 30%. The observed parameters included solution density, evaporation rate, and the content of NaCl, total hardness, and sulfate in the salt product. The results showed that recrystallization significantly increased the NaCl content and reduced impurities. Optimal conditions were achieved with a 22% salt solution, where crystal formation produced recrystallized salt with an NaCl content of 99.33%, total hardness of 0.47%, and sulfate content of 8.56 ppm. This quality has the potential to meet industrial salt standards. This study can serve as a reference for industrial salt production on a larger scale.
Utilization Of Sengon Wood Sawdust Waste as Esterified Cellulose-Based Bioadsorbent for CD(II) Wastewater Purification Fauzan, Rizky; Mujahidah, Nisa Rahmah; Nugraha, Teguh Aditya; Azzahra, Nasya; Paramitha, Tifa; Soeswanto, Bambang; Sihombing, Rony Pasonang
Journal of Green Science and Technology Vol 9 No 3 (2025): Journal of Green Science and Technology Vol. 9 No. 3 December 2025 Special Editio
Publisher : Faculty of Engineering, Universitas Swadaya Gunung Jati

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33603/jgst.v9i3.10650

Abstract

Cadmium (Cd) is a heavy metal with high toxicity that can enter the body through contaminated food chains, so wastewater containing cadmium needs to be treated before being discharged into the environment. This study uses adsorption methods to reduce Cd(II) concentration in artificial wastewater by utilizing modified sengon wood sawdust cellulose as a bioadsorbent. Adsorption tests were conducted in batch mode at room temperature with constant stirring, and the results were analyzed using AAS. The objective of this study was to determine the optimum adsorption conditions using Response Surface Methodology (RSM) and to determine the adsorption capacity of the modified bioadsorbent based on the Freundlich or Langmuir adsorption isotherm models. The variations in bioadsorbent dose in this study were 2, 4, and 6 g/L; adsorption time variations were 30, 60, and 90 minutes; pH variations were 3, 4, and 5. Based on the design expert 13 RSM software, the optimum adsorption conditions for citric acid-modified bioadsorbent are a bioadsorbent dose of 3.957 g/L, time of 31.655 minutes, and pH of 4.968. For the EDTA-modified bioadsorbent, the optimum conditions were a bioadsorbent dose of 3.836 g/L, time of 30 minutes, and pH of 4.708. The results of the adsorption isotherm modeling indicate that the citric acid-modified and EDTA-modified bioadsorbents are more suitable for the Freundlich isotherm model due to their higher determination coefficient (R²). Thus, the adsorption capacities for the citric acid-modified and EDTA-modified bioadsorbents were determined to be 1.7828 mg/g and 1.5776 mg/g, respectively.
Phosphate Reduction in Laundry Wastewater Using Activated Coffee Grounds and Fly Ash as Adsorbents Sihombing, Rony Pasonang; Christianti, Christianti; Ramadhani, Nabila Dwi Nur; Martadinata, Nadya Zafirra; Adhitasari, Alfiana; Kurnia, Dianty Rosirda Dewi
Journal of Green Science and Technology Vol 9 No 3 (2025): Journal of Green Science and Technology Vol. 9 No. 3 December 2025 Special Editio
Publisher : Faculty of Engineering, Universitas Swadaya Gunung Jati

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33603/jgst.v9i3.10651

Abstract

The growth and development of the population have significantly accelerated economic progress within society. Consequently, many new businesses have emerged, including commercial laundry services. One of the substances found in laundry wastewater, phosphate can cause eutrophication, which disrupts the balance of aquatic ecosystems. One method that can be developed to address this issue is adsorption technology. The aim of this research was to lower the phosphat content and to meet the Regulation of the Minister of Environment of the Republic of Indonesia No. 5 of 2014. The increasing number of coffee shops generates coffee grounds that have the potential to be processed into activated carbon. Additionally, fly ash a by-product of coal combustion contains silica and can be used as an adsorbent. The activated carbon is activated using 0.1 N NaOH and combined with fly ash in various compositions: 2:8, 4:6, 5:5, 6:4, and 8:2. Besides the variation in composition, contact time is also varied 30 minutes, 60 minutes, 90 minutes, 120 minutes, and 150 minutes. The observed parameters include pH and phosphate concentration at each contact time. The research results show that the optimal composition is 0.2AC:0.8FA with the highest phosphate removal efficiency of 60.3% at 150 minutes contact time and a pH of 7.1. However, the final phosphate concentration has not yet met the quality standard of 2 mg/L set by the Regulation of the Minister of Environment of the Republic of Indonesia No. 5 of 2014.
Utilization Of Coffee Grounds into Bio-Briquettes Using Various Types of Adhesives with Carbonization Method Yogeswari, Luh Putu Irma Sridewi; Yuliani, Nispi; Chiquita, Belva; Adhitasari, Alfiana; Leoanggraini, Unung
Journal of Green Science and Technology Vol 9 No 3 (2025): Journal of Green Science and Technology Vol. 9 No. 3 December 2025 Special Editio
Publisher : Faculty of Engineering, Universitas Swadaya Gunung Jati

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33603/jgst.v9i3.10652

Abstract

Coffee is one of the most widely produced and consumed agricultural commodities in Indonesia, with production rates increasing each year. This growing demand results in an increasing volume of spent coffee grounds, which are typically discarded as waste. One sustainable approach to managing this waste is by converting it into bio-briquettes, a form of solid fuel. This study aims to evaluate the physicochemical characteristics of coffee ground-based briquettes using different types of adhesives in accordance with the Indonesian National Standard (SNI 01-6235-2000) and to determine which adhesive yields the highest briquette quality. Three types of adhesives were tested: tapioca starch, sago starch, and polyvinyl alcohol (PVA), each mixed with carbonized coffee grounds in a 1:10 ratio. The briquettes were analyzed based on key performance indicators, including moisture content, ash content, volatile matter, density, fixed carbon, and calorific value. The carbonization process was applied prior to briquette formation to improve fuel quality. The results showed that the briquette using PVA as an adhesive exhibited the best overall performance, with a density of 0.449 g/cm³, ash content of 4.360%, moisture content of 1.480%, volatile matter of 33.974%, fixed carbon of 59.743%, and a calorific value of 6.861 cal/g. These findings suggest that PVA-based briquettes offer promising potential in reducing biomass waste and supporting the development of renewable energy in Indonesia.
Anodizing Characterization of Aluminum 1100 Composition of Sulfuric Acid - Oxalic Acid 16% With Aeration and Nonaeration at Different Time Intervals Nurcahyo, Nurcahyo; Rizky, Rian Muhamad; Diningrat, Mangku Joyo; Adihartanto, Synbi Pasya Octaviarine; Khoirunisa, Tira Nur; Paramitha, Tifa
Journal of Green Science and Technology Vol 9 No 3 (2025): Journal of Green Science and Technology Vol. 9 No. 3 December 2025 Special Editio
Publisher : Faculty of Engineering, Universitas Swadaya Gunung Jati

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33603/jgst.v9i3.10653

Abstract

Aluminum is a type of metal that is widely used in the industrial and household fields. This study aims to analyze the effect of variations in sulfuric acid and oxalic acid concentrations, as well as aeration systems, on the surface characteristics of aluminum 1100 through the anodizing process. The anodizing process is one of the surface treatment processes that is carried out with the aim of improving or improving the properties of a metal, including resistance to wear, increasing hardness, and aiming to beautify the appearance itself. This anodizing test is with sulfuric acid-oxalic acid electrolyte solution, electrolyte concentration 16%, at room temperature with a current density of 3/dm2 in time intervals of 20 minutes and 30 minutes. The data obtained from the test results showed that the oxide layer was formed maximally in the aeration system with a concentration of 13.5+2.5 and a time interval of 30 minutes of 0.0411 gr. This shows that the addition of oxalic acid and oxygen can accelerate the formation of the oxide layer. At electrolyte concentrations of 16+0, 15.5+0.5, 15+1, 14.5+1.5 and 14+2, there was an increase in the difference in oxide mass by 0.0337 gr, 0.0335 gr, 0.0366 gr, 0.0390 and 0.0411 gr.
Effectiveness Of Activated Carbon Of Reed (Imperata Cylindrica) As Methyl Orange Bioadsorbent with Batch Adsorption Method Suminar, Dian Ratna; Harianto, Dicky; Fauziah, Najmi; Febrian, Dea Tri; Kharisma, Luthfiana; Paramitha, Tifa
Journal of Green Science and Technology Vol 9 No 3 (2025): Journal of Green Science and Technology Vol. 9 No. 3 December 2025 Special Editio
Publisher : Faculty of Engineering, Universitas Swadaya Gunung Jati

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33603/jgst.v9i3.10655

Abstract

The use of synthetic textile dyes causes environmental problems, namely the waste produced is still colored and difficult to degrade. Methyl orange is a synthetic dye in the textile industry which has low solubility in water, is difficult to degrade, has the potential to be carcinogenic and is toxic. To overcome this, adsorption can be carried out using activated carbon from reeds. This research aims to find out how active carbon of reeds is absorbed in methyl orange using the batch method with Langmuir isotherm analysis. Research methods include pretreatment of reeds, manufacture and activation of reeds carbon, testing the characteristics of activated carbon, adsorption process, and analysis of adsorption results using a UV-Vis spectrophotometer. The research was carried out by varying the concentration of methyl orange solution, adsorption time, and mass of activated carbon used. From the research, optimum conditions were obtained for the methyl orange adsorption process using reed activated carbon for 120 minutes with an activated carbon mass of 0.3 grams, a final concentration of 7.328 ppm was obtained with an initial concentration of 10 ppm, and a % adsorption of 26.72%.
Optimization Of Coffee Grounds and Fly Ash Based Adsorbent Composition with Phosphoric Acid Activator for Tofu Industry Liquid Waste Purification Alfithroh, Mustika Agustini; Fattah, Khalaida Fania; Zulfikar, Yusup Muhammad; Tsuroyyaa, Zakiyyah; Zaharani, Feby Nurghaida; Adhitasari, Alfiana
Journal of Green Science and Technology Vol 9 No 3 (2025): Journal of Green Science and Technology Vol. 9 No. 3 December 2025 Special Editio
Publisher : Faculty of Engineering, Universitas Swadaya Gunung Jati

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33603/jgst.v9i3.10662

Abstract

The direct disposal of tofu industrial wastewater without treatment can have negative impacts on the environment due to its organic content. One effort that can be done is to process tofu liquid waste using the adsorption method. Nowadays, coffee shops are growing rapidly in indonesia, resulting in a lot of coffee grounds waste which can be used as raw material for activated charcoal because of its carbon content. In addition to coffee grounds, other waste in the form of fly ash is also used as an adsorbent because of its silica content. This study aims to determine the optimization of the composition of coffee grounds and fly ash adsorbents in the purification of tofu industry liquid waste and to determine the optimum contact time so that liquid waste is obtained in accordance with quality standards. Observation parameters include acidity (ph) and chemical oxygen demand (cod). Coffee grounds charcoal is activated using 0.1 n h₃po₄ solution then mixed with fly ash in a ratio of 20:80; 30:70; 50:50; 70:30; and 80:20. The adsorption process is carried out in batches for 60, 90, and 120 minutes. The results of the study showed the optimum composition of the adsorbent 20:80 and contact time 120 minutes with a final cod of 2,761 mg/l, ph 6.21, and a cod reduction of 80.46%.

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