bluuebunny/crossref_metadata_2025_split huggingface dataset:
Implementing Risk-Based Maintenance Strategies for Distributed Control System as Power Plant Asset Management
Authors: Yulianto D T , Isman R M , Ihsan S N , Susanto H G 
Published: March 2021

Abstract
The electricity generated from the power plant is subject to several requirements for active power, voltage, and frequency according to the grid system, so the machine must be controlled to achieve requirement by a power plant control system knows as Distributed Control System (DCS). DCS system in block 1 Muara Tawar power plant using Procontrol P-13 for gas turbine and Procontrol P-14 to control steam turbine. These systems had operated since 1997 and had been nearly operating for 23 years until now, and several failures tend to increase from time to time. The failures of the DCS and the lack of control cards will result in the loss of production. DCS system assets must handle properly to maintain the overall reliability of the power plant system. A method and strategy to maintain DCS must be carried out and ensure reliability and risk always under controlled conditions. Implementing Risk-based maintenance by carrying out quantitative calculations through the reliability approach and the level of the consequence of failure to calculate equipment risk is one of the methods of the DCS system. The result of Risk-based maintenance method shows the highest risk on risk map of the DCS system was in cubicle 14CBA02, 14CBA03 with a high-risk level and gas turbine and HRSG cubicle in medium-high level. The interval preventive maintenance time calculated by reliability within a year showed that cubicles 14CBA02 and 14CBA03 suggested to be maintenance every 29 days to reduce possibilities to failure.
Cavitation Draft Tube Analysis of Francis Turbine Loads Variations: A Case Study from Cirata Hydropower Plant
Authors: Sibuea R T , Mirmanto H 
Published: March 2021

Abstract
Hydropower plant (PLTA) is a power plant of EBT (Renewable Energy), which utilizes water as a primary energy source. PLTA has a very important role in balancing the stability of network systems. In improving network system stability, hydropower is operated in a wide load range, frequent start-stop, and varying loads. Other functions are also as a buffer of peak load and back up system in case of interference in the network system. Francis turbine is the most widely used turbine and has a maximum efficiency of 93-95%. Problems related to the operation of hydropower are operational instability, cavitation, vortex breakdown, pressure shocks, vibration and noise that sometimes cause turbine system failure. In relation to the above conditions then in this thesis will be studied how the occurrence of cavitation due to variations loading. Case study conducted in this research is at Cirata hydropower plant with capacity of 126 MW per unit, which has type Francis turbine vertical shaft (variation of load starts 40% and 100%). The research method is done numerically, with modeling and flow simulation using ANSYS CFX 18.2. The results of this study show that at 40% load-operating conditions there is a very low-pressure area (under vapor pressure) and the emergence of a vortex rope that causes cavitation in the draft tube area, especially in the elbow region. While at 100% load operating conditions only slightly visible low-pressure area and no vortex rope appears.
A Proposed Scheme and Future Development for Carbon Trading System in Indonesia based on Case Study in Muaratawar Add-On Power Plant
Authors: Adhiyoso A , Pardiansyah I , Akshinta P Y , Aryata I M 
Published: March 2021

Abstract
The growth of electricity demand in Indonesia has enforced the government to develop several large-scale power plants to electrify some region. Due to economical and operational aspects, mostly majority of plants are build based on coal-fired plant, where it can give bad impact to environment. Furthermore, some mitigation has been taken into account in attempt to reduce the GHC emissions. One of the options is by evaluating on a case in Muaratawar add-on project (Block 2, 3 and 4). The addition of HRSG at the plant is expected to reduce the GHG emissions to 0.48 Tons of CO2/MWh with a potential carbon reduction of 3.599.410.69 Tons of CO2/year. This paper concern on proposed business scheme for carbon trading through a comprehensive evaluation based on historical recorded data and baseline along with weighting and scoring method to select the best carbon trading system.
Study on PV System Development at UP Brantas for Hydroelectric Power Plant Station Service Supply
Authors: Irwan  
Published: March 2021

Abstract
Concern toward the preservation of natural resources became one of the attention for the generation industry in Indonesia. Thus the development of renewable energy in the generation sector is important. Several hydropower plants of UP Brantas have the potential to develop PV systems in the Kolam Tando Harian (KTH) and the tailrace area. The hydropower as the object of this study, the average needed for the hydropower electricity station service per year can be calculated by calculating the PV system with 5% - 80% of the potential area that has been determined. Due to the station service costs of hydroelectric power stations increases at 0.172 $/kWH, the development of PV systems is an alternative solution to reduce the cost of hydropower station service. Refers to the capital cost of PV & energy storage issued by Lazard in 2019, it is known that the LCOE value for PV development in UP Brantas hydropower ranges between 0.11 - 0.21 $/kWH. Compared to the import energy tariff of 0.172 $/kWH, the development of this PV plant is potential and realistic to implement. This program is aligned with government and company policies in realizing the strategic goals of renewable energy development. The development of this PV plant can be integrated later into the hydropower load center using a hybrid decentralized grid-connected PV system configuration with or without battery energy storage.
Analysis of Muara Tawar CCPP Block 1 Steam Turbine Vibration
Authors: Hidayat Asnawadi , Firmansyah Iman , Wasiwitono Unggul 
Published: March 2021

Abstract
Condition monitoring of steam turbine enables early detection of faults and avoid unexpected breakdowns. Vibration analysis has gained much attention in the field of condition monitoring because of its accuracy in detecting faults and its ability for proper diagnosis of the faults. Muara Tawar CCPP block 1 has a steam turbine generator with a capacity of 215 MW. Steam turbine roll after inspection shows high vibration occurs on bearing 1. This study aims to find the cause of this high vibration and provide recommendations to avoids such symptoms. The vibration data used in the analysis are obtained from vibration analyzer tools associated with vibration monitoring systems. It is found that the amplitude of vibration at rotational speed frequency (1X) increased and phase angle changes at a constant speed. The vibration level at the coast down is higher than the observed vibration level at run-up. There is a shift in the position of critical speed which indicates a change of rotor stiffness. It is concluded that the high vibration is likely by a thermal bow on the rotor. The thermal rotor bow is caused by a light partial rubbing between rotor and labyrinth seal on the stator.
Collaboration Holistic Enterprise Architecture and Asset Management System for Power Generation
Authors: Setiyowati Rianti , Zemmy M , Agung P J 
Published: March 2021

Abstract
Asset Management becomes the most important part of managing power generation sector. It will determine the success of efficiency and effectiveness as well as the economic value of an electric product that produced. Many power generation unit that must be managed and implementing asset management system according to the standard ISO 55001, the company no longer can not only focus on the operational terms but shifted to the strategic, where management is asked to be able to see the company in a holistic view and faster in making decisions. In this journal the authors convey the development done through the collaboration of Enterprise Architecture (EA) which is the blueprint of the organization that integrate between processes, data, applications and technology and asset management of the company as well as adding seven dimensions of performance indicators in one worksheet and linkage different from other EA through the development of application platform to digitalize the needs of the company in managing the asset that we called PJB-IMS 2.0, this concept can be a prototype for other generating company in implementing asset management system. The existence of EA realized in PJB IMS 2.0 is ensured to be in accordance with the challenges future business that increasingly complex.
Technical Study of Developing Floating Photovoltaic 145 MWac Power Plant Project In Cirata Reservoir
Authors: Sukmawan Toni , Nursyahbani Hanif , Wahyudi Hendras D , Gunawan Trenindya , Wijaya Adi A 
Published: March 2021

Abstract
This paper is concerning how the technical study of the 145 MWac Cirata solar Floating construction was built on the cirata dam. The Cirata floating solar power plant development plan starts with the Renewable Energy Mix target set by the Indonesian government as stipulated in the National Electricity General Planning Document 2018-2037 with a target of 23% renewable energy by 2025. Technical aspects of the study are carried out on several aspects such as availability land which will determine the type of PV Land Base or floating. with some technical considerations while eventually floating technology was chosen since has technical and financial advantages for the construction of solar power plants in this location. Subsequently, an evaluation was carried out to determine the potential for irradiation at the specific locationbju. After obtaining irradiation data and meteorological conditions, a projection of energy production in the location is carried out using the performance ratio parameters on several values to obtain the projection of annual energy production. An evaluation of interconnection was also carried out to find out whether the construction of the 145 MWac floating solar was safe against the reliability of the 150 kV and 500 kV systems in the West Java system.
Effect of Heat Input in Dissimilar Welding on SS304H and T22 to Hardness Distribution and Delta Ferrite Content with GTAW Process
Authors: Santosa A , Suwarno  , Laksana W A , Mantika F A 
Published: March 2021

Abstract
In this paper, a study was carried out on the effect of various heat input on the hardness distribution and delta ferrite content in dissimilar welding on T22 and SS304H tube boilers in power plants using Gas Tungsten Arc Welding (GTAW). The heat input used in this study is 2.9 KJ/mm, 3.1 KJ/mm and 3.6 KJ/mm. Controlling the heat input parameter is one method to reduce problems in dissimilar welding. The general problem occurs in dissimilar welding is the failure on the weldment to occur due to differences in chemical composition, mechanical properties and thermal coefficients of the two materials where it makes degradation in the microstructure in the fusion zone and creating residual stress than susceptibility to fatigue in material or cracks. All variation of heat input in this study is safe to operate in the welding process and low tendency to hot cracking. Using the lowest variation of heat input 2.9 KJ/mm has the highest value of hardness distribution and lowest FN value.
Power Generation Fire Risk Evaluation Using House of Risk (HoR) Method With an Asset Management Approach
Authors: Hamka D H , Sutarto D S , Pariaman H , Hisjam M 
Published: March 2021

Abstract
The risk of fire in power generation is the latest issue of concern to the electricity business. Several preventive programs such as coal dust control and the improvement of coal handling facilities to the provision of fire fighting infrastructure have been carried out continuously, but the main problem in the implementation of further work programs is finding the right policy in the main risk and determining the priority of mitigation. Integrating the House of Risk method with ISO 55001 can become an alternative to the previous methods that already exist and will be able to support the establishment of fire safety risk mitigation policies. A holistic review of business processes taking into consideration emerging risk agents in addition to risk events, risk impacts, and the occurrence of risk agents, then the method used will be able to generate a selected list of prioritized preventive actions. The results showed 41 risk events with 28 identified risk agents, furthermore, 17 risk agents were chosen as a preventive measure, and finally 8 proposed preventive actions to reduce the probability of the occurrence of risk agents that can lead to business interruption.
Full Loop Numerical Simulation of Fluidization Characteristics at Cyclone and Furnace of 110 MW CFB
Authors: Wirahadi A , Batubara P 
Published: March 2021

Abstract
Circulating fluidized bed (CFB) boiler has strong points with its recognition when operating with low quality coal contrast to pulverized coal boiler. Boiler load could be improved by increasing coal input and air ratio combustion adjustment. That is why ratio combustion between secondary and primary air is one of valuable parameters influencing fluidization of CFB Boiler. CFB boiler is consist mainly of a furnace, two cyclones, and forced loop pipes, where cyclones are boiler parts that were indicated to have high velocity fluidization up to 30 m/s. Full loop 3D simulation of CFB with focusing on the furnace and cyclone by using computational fluid dynamic (CFD) program was implemented using Eulerian multiphase model to investigate sand volume of fraction, air, and sand velocity including pressure distribution around Cyclone. Several air ratio combustions between primary and secondary air were simulated such as 55%-45%, 50%-50% with 63%, and 100% load variations. It was shown that operation with air combustion ratio 50%-50% and 55%-45% leads to good fluidization at 63% load, while 100% and 110% fluidization will cause an abundant sand entered to inlet cyclone and induce higher sands and air velocity.
Application of Theory of Constraints (TOC) in Power Generation to Increase Overhaul Maintenance Performance and to Strengthen Overhaul Management Process
Authors: Rahadi K B , Setyanto A , Rohmansyah D 
Published: March 2021

Abstract
Theory of Constraints (TOC) is a new concept of overhaul management in power generation. It has been effectively used in various industrial activities. This paper describes the idea of how the TOC is applicable to improve the overhaul management dealing with several constraints with a case of power plant overhaul performance. TOC uses all five application tools to analyze a system or situation to identify a core problem, develop a solution for it, and determine how to implement that solution. These applications are CRT (Current Reality Tree), EC (Evaporating Cloud), FRT (Future Reality Tree), PRT (Prerequisite Tree), and TT (Transition Tree). The result of the study has shown several main factors causing the achievement of power generation overhaul performance not optimum. Based on the main causes that have been identified, it will give also some recommendations for improving the power generation overhaul performance such as personnel competencies acceleration and overhaul management process strengthened.
A Reductive Pre-Treatment to Improve NCA Cathode Material Hydrometallurgical Recycle Process
Authors: Jumari A , Nizam M , Dyartanti E R , Suranto  , Yudha C S , Muzayanha S U , Apriliyani E , Purwanto A 
Published: March 2021

Abstract
NCA or LiNi0.8Co0.15Al0.05O2 (NCA) Battery is one lithium ion batteries (LIBs) that is often used in electric vehicles as an energy storage device due to its high capacity and energy density. But along with the popularity of electric vehicles, the production of NCA cathode materials has also increased so resulting in accumulation of LIBs waste in the future. The purpose of this study is to recycle NCA via hydrometallurgical route. The effect of reducing agent addition during the pretreatment process was investigated. Stearic acid, oxalic acid, citric acid and glucose were used as the reducing agent. Sulfuric acid and citric acid solution were used as the leaching agent. XRD analysis confirmed the occurrence divalent Ni due to reduction process. Based on the AAS analysis, it can be concluded that the reduction process affects the leaching behavior significantly. The highest leaching concentration of Ni and Co is obtained using glucose as the reducing agent during the pre-treatment.
Determination of Household Green Waste Fractions to Methane and its Economic Value
Authors: Joelianto E , Edyson H P 
Published: March 2021

Abstract
The methane gas produced at the landfills has become one of the main causes of the global warming. On the other hand, solid waste has potentials as a new energy. One of the well-known methods in processing solid waste into a new energy is methanation or anaerobic fermentation process. This paper considers calculation of the solid waste fraction of green waste that can be released as methane from traditional market. The gas volume is measured by using U-pipe filled with water. The difference of water height in the U-pipe is used to calculate the formed biogas volume used to calculate the weight fraction of the methane and amount of profit which can be generated from the solid waste processing by using anaerobic fermentation. The profits are obtained from the use of methane as the source of electricity energy and the profit of selling compost from the fermented trash residue. The results of this research show that the solid waste fraction which can be released as methane has the value range 0.11% - 0.18%, the benefits that can be generated from anaerobic process for organic solid waste are 300,899,290.00 IDR annually for electricity energy and 24,432,222,254.00 IDR annually for compost.
Synthesis of Modified Graphite with High Crystalline Na-LTO by Simple Doping Method.
Authors: Putra M I , Muzayanha S U , Rizal Y , Fadilah  , Widiyandari H , Purwanto A 
Published: March 2021

Abstract
Graphite doped with Na-Li4Ti5O12 (Na-LTO) for lithium-ion batteries with stable rateability were prepared in a short time by simple grounding which followed with the short calcination time. High crystalline Na-LTO improved the diffusivity of the Li-ion kinetics and stability. Therefore, Graphite/Na-LTO (G-NaLTO) was compared with the pure graphite to find out the differences in terms of XRD pattern and electrochemical performance. XRD analysis showed there was no significant differences pattern from G-NaLTO with commercial graphite. In terms of electrochemical performance, G-NaLTO which was doped by 1 wt% Na-LTO, presented a high initial charge capacity 356.69 mAh g−1 at 0.1C and stable discharge rate-capability at 0.2C and 1C were 264.64 mAh g−1 and 220.65 mAh g−1, respectively, after 15 cycles. G-NaLTO with a composition of 3 wt% Na-LTO shows a decreasing electrochemical performance so it can be concluded that the addition of 1 wt% LTO by the doping method is the most optimal.
Recent Development of Polyvinylidene Fluoride/Cellulose Membranes Electrolyte Separator for Lithium Ion Batteries
Authors: Dyartanti E R , Sunaryati N , Alhakim R R , Putri L N , Putri A Y M , Nurohmah A R , Nisa S S 
Published: March 2021

Abstract
Lithium ion batteries (LIB) are an important energy storage system. As one component in a LIB, the separator has an important role in the safety of LIB. Separators have porous structures that make it possible to transfer lithium ions between anode and cathode. This paper discusses the method for making separators with the main material as PVdF and cellulose. Such as casting, phase inversion, paper making, and electrospinning. So, we found two potential methods that can be developed in preparing lithium-ion battery separators, casting and electrospinning. Casting has benefits like a simple preparation step and does not require much equipment, but the weaknesses are expensive processes. The electrospinning step has advantages such as an inexpensive process, but has the disadvantage of needing much equipment.
Association of Stage 1 Hypertension Defined by the ACC/AHA 2017 Guideline With Asymptomatic Coronary Atherosclerosis
Authors: Yoon Yong-Hoon , Park Gyung-Min , Lee Jong-Young , Lee Jae-Hwan , Lee Hanbyul , Roh Jae-Hyung , Kim Ju Hyeon , Lee Pil Hyung , Choe Jaewon , Kim Young-Hak , Lee Seung-Whan 
Published: March 2021

Abstract

BACKGROUND
This study sought to assess the relationship between stage 1 hypertension and subclinical coronary atherosclerosis.

METHODS
A total of 4,666 individuals with available coronary computed tomography angiography (CCTA) results from a health checkup were enrolled. The classification of hypertension was adapted from the American College of Cardiology/American Heart Association (ACC/AHA) 2017 guideline. The presence of coronary plaques and its characteristics, and other CCTA findings were assessed.

RESULTS
There was a linear relationship between blood pressure (BP), both systolic BP (SBP) and diastolic BP (DBP), and the presence of coronary plaque. Patients were classified into 4 groups according to the BP category: normal BP (SBP &lt;120 mm Hg and DBP &lt;80 mm Hg; n = 2,395; 51.3%), elevated BP (SBP 120–129 mm Hg and DBP &lt;80 mm Hg; n = 467; 10.0%), stage 1 hypertension (SBP 130–139 mm Hg or DBP 80–89 mm Hg; n = 1,139; 24.4%), and stage 2 hypertension (SBP ≥140 mm Hg or DBP ≥90 mm Hg; n = 665; 14.2%). Compared with the normal BP group after multivariate adjustment, the stage 1 hypertension group was significantly associated with the presence of atherosclerotic plaque (adjusted odds ratio [95% confidential interval], 1.37 [1.17–1.62]; P &lt; 0.001), especially in noncalcified and mixed plaques. The relationship between stage 1 hypertension and stenosis &gt;50% was not statistically significant. Isolated diastolic and isolated systolic stage 1 hypertensions were significantly related to the presence of coronary plaque. The elevated BP group was not associated with any positive CCTA findings.

CONCLUSIONS
Stage 1 hypertension was independently associated with subclinical coronary atherosclerosis.
Understanding the Broader Impacts Of Alcohol Marketing: Time For a Research Agenda Which Includes Adults
Authors: Critchlow Nathan , Moodie Crawford 
Published: March 2021

Abstract
Most research on alcohol marketing involves young people. Consequently, gaps remain in our understanding of how alcohol marketing reaches, engages and influences adults, who are the legitimate and primary targets for marketing communications. Responding to these lacunae in knowledge is necessary to help inform and evaluate population-level controls on alcohol marketing.
The Development and Commercialization of Medical Technologies
Authors: Bertrand Anthony A , DeLong Michael R , Chandawarkar Akash , Robinson Chandler 
Published: March 2021

Abstract
It is not uncommon for physicians to think of ways to improve the delivery of care, which may take the form of a new medical device, drug, test, or service. In recent years, structured approaches to the identification of unmet needs and the development of solutions have been introduced to the medical community. Yet, due to gaps in exposure and training, there remains an opportunity to improve the level of understanding within the medical community regarding how to develop an innovation, once conceived, to the point of commercialization. The purpose of this article, therefore, is to provide an overview of some of the relevant considerations and requirements when bringing an idea for a new medical technology to market.