MOTIVECTION : Journal of Mechanical, Electrical and Industrial Engineering

Modification of Bentonite with Nano Silica Oxide (SiO₂) for the Purification Process of Crude Palm Oil (CPO)

Enny Nurmalasari, Agung Kurnia Yahya, Apsari Puspita Aini, Hasnah Ulia — Tue, 23 Sep 2025 23:45:09 +0000

The efficiency of β-carotene removal is a critical parameter in commercial refining, as it directly influences the overall process effectiveness; therefore, the selection of appropriate bleaching agents is crucial. The limited effectiveness of Bleaching Earth (BE) in refining crude palm oil (CPO) to meet color standards poses a challenge. To improve BE's performance, natural bentonite was modified with nano-SiO₂ through a facile-mixing method. Bentonite was modified with nano-SiO₂ in concentrations of 5, 10, and 15% w/v, to assess the effectiveness of this modified bentonite in the CPO bleaching process. Bleaching was conducted at 90°C with a BE concentration of 0.5% w/v for 30 minutes. Characterization confirmed successful integration of modified Bentonite indicated by enhancing surface area. Bentonite modified with 15% nano-SiO₂ showed a significant improvement in bleaching performance, reducing β-carotene content to 553.84 ppm compared to 630.36 ppm with unmodified bentonite. The red/yellow color value also decreased to 1.5/15 from the original CPO value of 2.1/21, along with a reduction in FFA value. The results of this study indicate that modifying bentonite with nano silica oxide offers a solution to reduce the amount of bentonite used in the bleaching process.

Design of an Off-Grid Solar PV System for a Renewable Energy-Based Home in Bengkulu

Tue, 23 Sep 2025 23:57:18 +0000

Bengkulu Province has a solar energy potential of 3,475 MW, with an average daily solar irradiance duration of 5.9 hours in 2022 and 8.3 hours in 2023. This study designs an off-grid solar PV system for a renewable energy-based home (REH) model in the coastal area of Bengkulu City. The REH is a home with electrical energy independence that utilizes renewable energy systems to generate electricity. This study focuses on the REH powered by solar energy, intended for a modest home with a power capacity equivalent to a 900 VA PLN customer classification. The data on solar energy potential in the coastal area of Bengkulu City used in this study is from the Global Solar Atlas. The data analysis confirmed the need for the REH model to generate electricity from solar energy, requiring 12 units of 120Wp PV modules in a PV array. An appropriate solar charge controller for this REH model is the MPPT SCC with a rating of 48 V 30 A. Based on the selected PV modules and the daily load of the REH model, the required 48 V battery capacity is 300 Ah, and the PSW Inverter 2,000 VA 48 V.

Contribution of B35 Biodiesel to Indonesia’s Renewable Energy Target and Challenges for B40 Implementation

Wed, 24 Sep 2025 00:10:59 +0000

Indonesia aims for 23% renewable energy by 2025 and a 29% reduction in greenhouse gas emissions by 2030 under the Paris Agreement. B35 biodiesel, a blend of 35% palm oil-based biodiesel and 65% diesel, is a key strategic solution for this energy transition. This study, using a mixed method approach with regression analysis, analyzed data from the Ministry of Energy and Mineral Resources and Indonesian palm oil industry reports. It aimed to quantify B35's contribution to the renewable energy mix and project outcomes for a potential B40 policy. An in-depth analysis was conducted to identify the success factors and challenges of biodiesel implementation. Results show B35 biodiesel significantly contributes to Indonesia's renewable energy goals, reaching 38% in 2023 and 38.75% in 2024. Its implementation also led to substantial savings of IDR 120.54 trillion in 2023 and IDR 123 trillion in 2024 by substituting fossil fuel imports. Regression projections suggest that B40 biodiesel could further increase renewable energy contributions to 40.7% with a 15.62 million kL production target in 2025. Additionally, biodiesel usage reduces CO₂ emissions by 8-11% compared to conventional diesel. In conclusion, B35 biodiesel plays a vital role, contributing nearly 40% to Indonesia's national renewable energy. For successful B40 implementation and to optimize biodiesel's role in achieving 2025 targets, a stable Crude Palm Oil (CPO) supply, a USD 4.1 billion infrastructure investment, consistent policy frameworks, feedstock diversification, carbon tax implementation, and strong inter-ministerial collaboration are essential.

Environmental and Socio-Economic Impacts of Crude Palm Oil and Kernel Production

Dian Kristina, Feri Afrinaldi, Nilda Tri Putri — Wed, 24 Sep 2025 00:26:29 +0000

Palm oil had become one of Indonesia’s leading commodities, contributing significantly to national economic development; however, it faced sustainability challenges, particularly concerning greenhouse gas (GHG) emissions in line with international standards. This study examined the measurement of environmental impact per monetary unit of Crude Palm Oil (CPO) and kernel production in Palm Oil Mill X, by integrating environmental and socio-economic impacts through Eco-efficiency Analysis. The environmental impact assessment was conducted using the Life Cycle Assessment (LCA) method, while the socio-economic impact values were measured using the Economic Input-Output (EIO) method. The data used in this study consisted of primary data and secondary data. Primary data were collected directly from Palm Oil Mill X, including information on production volumes, energy consumption and waste generation. Secondary data were obtained from published literature, government reports and national statistical database to complement and validate the primary data used in the analysis. The study evaluated eleven environmental impact categories, one of which was GWP. The research findings indicated that for a functional unit of 1 ton of CPO, the GWP was measured at 556.31 kg CO₂ eq/ton CPO, with approximately 80% of the GWP originating from CPO processing and wastewater (POME). In terms of socio-economic aspects, the wage multiplier was recorded at 0.930 and the tax contribution at 0.0698, demonstrating the significant contribution of the palm oil industry to labor income. The final economic contribution value (G⁺) was noted to be Rp 23,728,407/ton CPO. The results of the Eco-efficiency Analysis revealed that the GWP per Rupiah was 2.34 × 10⁻⁵ kg CO₂ eq/Rp, indicating opportunities for emission reduction through the use of cleaner energy. This study provided a quantitative overview of the interrelationship between environmental performance and socio-economic benefits, serving as a strategic reference for enhancing the sustainability of the palm oil industry.

Effect of Furnace Heating Temperature on the Hardness and Corrosion Resistance of Plain Carbon Steel

Wed, 24 Dec 2025 09:38:35 +0000

Microstructure modification of the plain carbon steel usually enhances hardness and corrosion resistance. Therefore, in the present research, the microstructure of plain carbon steel is modified by heating it in an electric furnace using various temperatures and then quenching it in engine oil to enhance corrosion resistance and hardness. Several characterizations were conducted, such as microstructure, hardness, and electrochemical behavior. The microstructure evolution indicates a clear transformation of martensite morphology with decreasing austenitizing temperature. Decreasing the furnace's heating before quenching could increase the specimens' hardness and corrosion resistance, with values around 586.36 HV and 0.135 mmpy. Therefore, the optimal heat treatment condition for plain carbon steel components in marine environments was found at 800 °C based on the results of this study.

Impact of Temporary Voltage Grid Disturbance to Running Speed of Three Phase Induction Motor

Wed, 24 Dec 2025 09:43:54 +0000

In the electric power system, especially the distribution system, several disturbances may occur. Voltage grid disturbance is an important power quality problem on the distribution side especially for industry with dynamics loads consisting many three phase electric motors. As the voltage grid disturbance appears, the electrical load especially an induction motor is expected to keep running on the rated speed. This motor condition is also well known as ride-through capability. In this article, the influences of temporary voltage grid disturbances are analysed to know the running speed of an induction motor based on difference in moment of inertia and give further information about the ride through capability by using PSIM simulation as an experimental tool. There are various types of voltage grid disturbance drop will be proposed. The proposed types of voltage grid disturbance to be observed are short duration sag, long duration sag, momentary swell and momentary interruption. The experiential conventional methods observed in the works are direct on line, wye-delta and autotransformer. The PSIM simulation results demonstrate that increasing the rotor moment of inertia from 0.4 to 0.8 enhances the dynamic resilience of the motor by reducing the average speed deviation by approximately 9.76% during a long-duration voltage sag. Meanwhile, the momentary interruption is identified as the most severe grid disturbance, as it leads to a complete loss of electromagnetic torque and consequently causes motor stalling. These findings highlight that the mechanical inertia of the drive system plays a critical role in maintaining motor stability during abnormal supply conditions. Finally, this article provides quantitative evidence on the combined influence of inertia and disturbance severity, offering valuable insight for the optimal design of protection schemes and motor selection criteria in industrial applications.

Low Voltage Interior Permanent Magnet Synchronous Motor (IPM PMSM) Design for Agricultural Robot Drive

Ahmad Awaluddin Baiti, I Wayan Adiyasa, Muslikhin Muslikhin — Wed, 24 Dec 2025 09:50:06 +0000

The growing demand for autonomous agricultural robots requires compact, energy-efficient 12 V drives. This work designs a 12 V Interior Permanent Magnet Synchronous Motor (IPM PMSM) for field robots with targets of torque >0.8 Nm, speed >1000 rpm, and outer diameter <100 mm. Two rotor options—baselines 0° and 12° skew—were optimized and evaluated via finite-element analysis of torque, back-EMF, efficiency, and thermal behaviour. Compared with 0°, the 12° skew cut torque-ripple RMS from 0.2885 to 0.1390 Nm (−51.8%) and reduced cogging torque by >50%, while peak torque decreased only slightly (1.85 → 1.81 Nm; −2.4%). Efficiency remained high (~89%), power factor improved (0.95 → 0.964), and passive cooling kept temperatures ≤65 °C at 60 minutes. These results indicate that a 12° skew provides a practical design trade-off for low-voltage agricultural PMSMs, delivering smoother, more stable torque for precision tasks such as seeding and spraying without sacrificing overall efficiency.

Design and Experimental Evaluation of a Mid-Drive Electric Bicycle with BLDC Motor Bracket and Gearbox Integration

Wed, 24 Dec 2025 10:05:09 +0000

Electric bicycles with mid-drive systems provide better weight balance and performance, particularly on uphill terrain. However, their production cost is generally higher than hub-drive systems, limiting accessibility for wider users. This study aims to develop a cost-effective mid-drive conversion system by modifying a hub-drive e-bike using a custom steel bracket and an integrated gearbox, and to evaluate its power performance and energy efficiency. The prototype was powered by a 60V 15Ah LiFePO₄ battery and tested under laboratory and road conditions, including no-load, flat-road, and uphill tracks (5°–15° slopes). Data were collected using a tachometer, GPS, and PZEM-015 module to record speed, voltage, current, and power consumption. The motor required 659 W during acceleration from 0–10 km/h, decreased to 183 W at 19 km/h, and increased to 867 W at 39 km/h. Under a 15° incline, the e-bike maintained 15 km/h with 1120 W of power. Distance-based tests (2.08–4.07 km) showed stable energy consumption between 21–26 Wh/km, increasing proportionally with rider weight. The gearbox-assisted mid-drive conversion improved torque distribution, transmission efficiency, and energy performance, providing a practical and affordable alternative for developing efficient electric bicycles.

Bayesian Network Integration of Event Tree and SLIM-Based Human Reliability for Fire and Explosion Risk Assessment: BP-Husky Toledo Refinery Case Study

Fairuz Putra Hanem, Adhitya Ryan Ramadhani — Sat, 27 Dec 2025 06:32:50 +0000

The oil and gas processing industry is critical for meeting global energy demand, yet it remains vulnerable to high-consequence accidents such as fires and explosions. This study presents a probabilistic risk assessment of a vapour cloud explosion and fire case at the BP-Husky Toledo Refinery using accident investigation report data. The objective is to obtain a more comprehensive representation of accident risk by integrating the performance of physical safety barriers and human reliability within a single analytical framework. Physical escalation pathways and consequence scenarios are modelled using event tree analysis, while human error likelihood is evaluated using the success likelihood index method based on identified error modes and performance shaping factors. Both components are then integrated using a Bayesian network to quantify consequence probabilities and examine the effect of adding a human error barrier and proposed barrier improvements. The results show that the consequence distribution is dominated by near-miss outcomes (approximately 57%) with smaller probabilities for flash fire (about 14%), vapour cloud explosion (about 13%), and rupture (about 16%). Incorporating the human error barrier produces only marginal changes in these probabilities. Nevertheless, the integrated approach improves clarity in linking specific human error mechanisms and barrier performance to overall risk and supports structured evaluation of barrier improvements for accident prevention.