Envirotek : Jurnal Ilmiah Teknik Lingkungan

Manufacturing of Paving Blocks From Red Brick Waste And Water Treatment Sludge From Perumdam Tirta Wijaya Kabupaten Cilacap

Khairullah Aji Izzudin, Ilma Fadlilah, Nur Indah Wardani — Tue, 30 Jun 2026 00:00:00 +0000

Construction waste such as broken red bricks and sludge from drinking water treatment is still an environmental problem that has not been used properly. This final project aims to recycle both types of waste into paving blocks as a way to support sustainable development and reduce environmental pollution. The research was carried out by mixing cement, sand, water, red brick waste, and water treatment sludge from PERUMDAM Tirta Wijaya Kabupaten Cilacap, with five different composition variations. The production process included mixing, molding, drying, curing, for 28 days, and testing the paving block quality based on the SNI 03-0691-1996 Paving Block standard. The parameters tested were compressive strength, water absorption, abrasion resistance, and resistance to sodium sulfate (Na₂SO₄). In addition, chemical analysis of the sludge was done using X-Ray Fluorescene (XRF) instrument. The results showed that the paving block with a composition of 75% red brick waste and 25% water treatment sludge from PERUMDAM Tirta Wijaya Kabupaten Cilacap had the best performance and met the D quality classification based on SNI 03-0691-1996 Paving Block, with a compressive strength of 10.54 MPa and water absorption of 8.81%.

The Effect of Pump Pressure in Improving the Quality of Peat Water Treatment Throught Nanofiltration: Effectiveness

Sriani; Akhmad Yani, Gusti Z. Anshari — Tue, 30 Jun 2026 00:00:00 +0000

Objective: The study aimed to evaluate the effectiveness of nanofiltration at different pressures in reducing turbidity, colour intensity, organic matter, Fe, TDS, as well as Total Coliforms and E. coli in peat water.

Methods: This research employed a quasi-experimental design with a quantitative approach. The tested pressures were 30 Psi, 40 Psi, and 60 Psi, each repeated 9 times, resulting in a total of 27 samples. The tested parameters included turbidity, colour intensity, organic matter, Fe, TDS, Total Coliform, and E. coli. Sample analysis was conducted at the Laboratory of Standardisation and Industrial Service Agency in Pontianak, West Kalimantan. Data analysis was performed using One-Way ANOVA and Kruskal-Wallis tests.

Result: The effectiveness of nanofiltration, such as turbidity (98.98%) with a p-value of 0.539>0.05, TDS (92.04%) with a p-value of 0.0567>0.05, organic matter (97.18%) with a p-value of 0.808>0.05, and Fe (90.83%) with a p-value of 0.613>0.05. Statistical tests indicate no significant difference between pressures (p-value 0.05).

Conclusion: Variations in pump pressure have a significant effect on the quality of peat water in achieving clean water standards. To achieve drinking water standards, further processing such as reverse osmosis is needed.

Analysis of Final Disposal of Fecal Waste and Wastewater in Dense Urban Settlements

Tue, 30 Jun 2026 00:00:00 +0000

Access to sanitation in dense settlements is critical. Neighborhoods with communal toilet facilities and groundwater supply sources are important sectors for households that do not have private toilet facilities and do not subscribe to the city's piped sewerage system. This paper aims to examine the system for managing domestic waste of communal toilets in dense settlements of Bandung City, West Java. From December 2022 to May 2024, to meet the research objectives, we used questionnaires and surveys in a quantitative descriptive method; analyzing the waste management of communal toilets that have groundwater supply sources, liquid and fecal waste management, and toilet hygiene were assessed by considering the real conditions of the environment. Domestic waste has not been managed optimally, still causing environmental pollution and affecting groundwater quality. Domestic waste management, considering social and demographic factors, needs a sustainable sanitation system with more effective and efficient waste handling, as 46.7% of households finally dispose of the river, 37.5% to septic tanks, and 15.8% of homes are linked to public piped sewage systems. Limitations of the study are only applicable to the study site of West Java, Indonesia, based on recent historical data.

The Paradox of Small-Scale Gold Mining and Sustainable Development: An Analysis of GRDP, Poverty, and Environmental Quality Index in West Lombok Regency

Haerul Anwar, Ahmad Fathoni — Thu, 30 Apr 2026 00:00:00 +0000

Small-scale mining activities are one of the growing economic activities in West Lombok Regency and have the potential to contribute to the socio-economic conditions of the community. This study aims to analyze the relationship between the contribution of the mining sector to the Regional Domestic Product (RDP) and the poverty rate as well as the Environmental Quality Index (EQI). The study uses a quantitative approach with simple linear regression analysis of secondary data for the 2019-2023 period sourced from the Central Statistics Agency and the Ministry of Environment and Forestry. The results show that the contribution of the mining sector to GRDP is relatively small, ranging from 2.01% to 2.08% of the total regional economy. The analysis results show that the contribution of the mining sector has a strong relationship with the poverty rate with a coefficient of determination value of R² = 0.8897 (≈0.8), indicating that an increase in mining activity is associated with a decrease in the poverty rate. This condition is related to the involvement of local communities in mining activities as a source of livelihood. Meanwhile, the relationship between the contribution of the mining sector and the quality of the environment shows a relatively weak relationship with an R² value of 0.2108 (≈0.2). This indicates that changes in environmental quality are not only influenced by mining activities but also by various other environmental factors.

Life Cycle Assessment (LCA) Analysis of Robusta Coffee Factory

Wiratama I Gusti Ngurah Made, I Made Wahyu Wijaya, Fransiskus Vebrian Kenedy — Tue, 30 Jun 2026 00:00:00 +0000

A coffee processing system must be evaluated using a life cycle assessment approach to understand its environmental impacts arising from its entire production process. This study aims to evaluate the environmental impacts associated with the production of robusta coffee at UD. Cipta Lestari, located in Pujungan Village, Tabanan Regency, Bali. The assessment was carried out using the Life Cycle Assessment (LCA) approach, a systematic method for evaluating the environmental impacts throughout the entire life cycle of a product, from raw material acquisition to final output. This research employed a descriptive quantitative approach, following the ISO 14044:2006 standard for LCA implementation. Additionally, greenhouse gas (GHG) emissions were calculated based on guidelines provided by the Intergovernmental Panel on Climate Change (IPCC) 2006. The results indicate that processing 1,000 kg of robusta coffee cherries yields approximately 516.5 kg of ground coffee. The total energy required for the processing was 1,476.8 megajoules (MJ) per ton of coffee cherries. Energy consumption analysis revealed that the production process accounted for 74.13% of total energy use, transportation activities 23.43%, and packaging 2.44%. Furthermore, the total GHG emissions from robusta coffee processing were estimated at 111.38 kg CO₂eq/ ton of fresh coffee cherries, or approximately 0.22 kg CO₂eq/ kilogram of ground coffee. These findings serve as a foundation for developing strategies to reduce environmental impacts and promote sustainable production practices.

Analysis of Environmental Noise Levels and LTM10 Values at Sumbawa University of Technology and Their Compliance with the Threshold Limit Value

Audina Setya Fitriana — Tue, 30 Jun 2026 00:00:00 +0000

Environmental noise represents a form of physical pollution that may interfere with comfort and academic concentration in educational settings. This study aims to analyze environmental noise levels at Sumbawa University of Technology using the 10-minute equivalent continuous sound level (LTM₁₀) and to assess their compliance with the applicable Threshold Limit Value (TLV). Measurements were conducted at four strategic campus locations: the Rectorate Building frontage, the Faculty of Environmental and Mineral Technology (FTLM) roundabout, the Integrated Laboratory (ITL) intersection, and the SIKIM intersection. Each site was monitored for 10 minutes using a Sound Level Meter (SLM). The recorded LTM₁₀ values ranged from 57.49 to 77.54 dB(A), with the highest level observed at the ITL intersection and the lowest at the FTLM roundabout. All locations exceeded the 55 dB(A) noise limit for educational areas as stipulated in Decree of the Minister of Environment No. 48 of 1996, although they remained below the occupational exposure limit of 82 dB(A). These results indicate that campus noise levels have surpassed acceptable acoustic comfort standards, underscoring the need for effective noise mitigation strategies to enhance the quality of the learning environment.

Effect of Gas Flow Rate on Hydrodynamics and Dissolved Oxygen Characteristics in a FineBubble Aeration System: A CFD-Based Study

Tue, 30 Jun 2026 00:00:00 +0000

This study evaluates the effect of gas flow rate on hydrodynamic behavior and dissolved
oxygen (DO) profiles in a lab-scale fine-bubble aeration system using computational fluid
dynamics (CFD). Triplicate experiments were conducted in a 17.06 L batch reactor containing
domestic wastewater, with a disk aerator operated at gas flow rates of 0.5, 1.0, and 1.5 L/min.
CFD was applied to interpret internal flow behavior through velocity contours and streamline
patterns. The results showed that DO increased significantly with higher gas flow rates (p <
0.05), with 1.5 L/min achieving the highest final DO of 6.73 ± 0.12 mg/L. CFD analysis
indicated that higher gas flow rates produced more developed circulation patterns, although
the area-weighted average velocity magnitude on the selected plane decreased from 0.0317
m/s at 0.5 L/min to 0.0203 m/s at 1.5 L/min. These findings suggest that oxygenation
improvement was governed not only by mean liquid velocity, but also by gas input and internal
flow organization. This study uniquely integrates experimental DO measurements with CFDpredicted hydrodynamic behavior in a laboratory-scale domestic wastewater aeration system.

Life Cycle Assessment (LCA) of Palm Oil Boiler Ash (POBA) Implementation Scenarios as an NPK Fertilizer Alternative Substitution in Palm Oil Plantations

Tue, 30 Jun 2026 00:00:00 +0000

Indonesia is the world's largest producer of CPO, with high demand to meet global vegetable oil needs. To maintain the plantation productivity, NPK fertilizer provides additional nutrients. However, their intensive use has negative impacts on the environment, including causing imbalances in aquatic ecosystems due to agricultural run-off that promotes eutrophication and ecotoxicity. In addition, Palm Oil Boiler Ash (POBA) is a waste generated from CPO mill boilers, which is generally underutilized. Nevertheless, POBA has the potential to improve soil quality, although improper management may cause a pH imbalance in water bodies. This study modeled the POBA implementation as an alternative to NPK fertilizer with a Life Cycle Assessment (LCA) approach to evaluate the potential for reducing environmental impacts. The scenarios consisted of 0% or operational conditions, 10%, 30%, and 50% substitution of NPK fertilizer with POBA. openLCA 2.5.0 was used for impact calculation, supported by primary data, and secondary data from the Ecoinvent database 3.11. The results indicated a significant reduction in impact values, particularly in the eutrophication and ecotoxicity categories, with increasing proportions of POBA substitution. This modeling provides the palm oil industry with environmental improvement programs aimed at mitigating impacts and achieving sustainability goals.

Understanding Roadside Air Quality in a Traffic-Dominated Urban Corridor: A Case Study of Sangkuriang Road, Cimahi Utara, Indonesia

Tue, 30 Jun 2026 00:00:00 +0000

Traffic emissions and local dispersion conditions exert a considerable influence on urban roadside air quality. This study aims to assess the ambient air quality and pollutant dispersion, resulting from the daily traffic on Sangkuriang Road in Cimahi Utara-Indonesia by
integrating traffic characteristics, roadside field measurements, and CALINE4 dispersion modelling to evaluate near-road pollutant behaviour. Traffic characteristics were analyzed using volume, composition, speed and volume-to-capacity ratio (VCR) while ambient concentrations were measured and compared with national air quality standards. Traffic and meteorological conditions were used to simulate the dispersion patterns using the CALINE4 line-source model. The motorcycles dominated the flow of traffic, with VCR values indicating stable conditions. Concentrations of pollutants at monitoring site were lower than the national limits, but dispersion modelling indicated higher concentrations close to the road that decreased rapidly with distance from traffic. The combined influence of motorcycle dominated traffic and low wind speed conditions (0.28 m/s) likely reduced pollutant dispersion and enhanced near-road pollutant accumulation. CALINE4 was able to reasonably capture the observed roadside pollution patterns and near-road dispersion behaviour. The results underscore the need for a combined monitoring and modelling approach in order to better understand spatial heterogeneity and exposure risks of near-road environments.

Identification and characterization of Microplastics in the Kartamantul Water Supply System, Yogyakarta, and its Potential Human Exposure

Thu, 30 Apr 2026 00:00:00 +0000

Microplastics are emerging contaminants that can enter drinking water systems from raw
water sources. This study is the first to evaluate microplastics across all treatment stages of
the Kartamantul Regional Water Supply System (RWSS) in Yogyakarta. Water samples were
collected from nine points along the treatment process (intake to customer taps) and analyzed
using a modified NOAA method with organic matter digestion, filtration, and microscopic
observation. Supporting parameters (pH, temperature, turbidity, TSS) were assessed via
Spearman’s correlation. Results showed the highest concentration at the intake (964
particles/100 mL), decreasing to 55 particles/100 mL at the clearwell (94.3% removal).
Fragments dominated, with black microplastics being most persistent. Estimated daily
exposure at household taps averaged 18.73 particles/kg body weight/day. Turbidity and pH
showed strong positive correlations with microplastic abundance. These findings indicate
conventional treatment effectively reduces microplastics, but additional measures are needed
at final treatment stages and within distribution networks to limit consumer exposure