bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the forecast reliability of site effect for regional mining tremors
Authors: Dubiński Józef , Stec Krystyna , Holeczek Grażyna
Published: November 2018

It is obligatory for Polish underground mines of hard coal and copper to prepare long-term exploitation projects for 2 - 5 years. All the natural hazards, including seismic ones, that may occur have to be taken into account in such projects. In the case of mining seismicity the forecast of site effect plays an important role. To recognize the reliability of this forecast for strong regional mining tremors special methodology was used. The peak ground velocity and peak ground acceleration, recorded after the occurrence of a regional tremor by surface seismometric network stations, were compared with the distribution of the forecast values of these parameters determined for similar seismic energy. Differences between these values are the basis for the evaluation of the reliability of the forecast site effect. The practical implementation was presented with the tremor of seismic energy E = 5.108 J (ML = 3.63) which occurred on 18th January 2018. The small value ΔPGVHmax (4%) of the difference between the recorded PGVHmaxrec and the forecast values PGVHmaxpr confirms that the measurement values correlate well with the forecast values. The difference value ΔPGAH10 for the peak ground acceleration equals 31% showing a worse correlation with the forecast data.
GPR ground-wave parameters changes due to variation of soil moisture
Authors: Marcak Henryk , Tomecka-Suchoń Sylwia , Czarny Rafał , Pysz Paweł , Akinsunmade Akinniyi , Kril Tetiana
Published: November 2018

The soil moisture distribution is important in terms of assessment of agricultural conditions for plant cultivations. The aim of this study is to develop methodology for monitoring soil moisture by the use of goundpenerating radar (GPR). This non-invasive geophysical method has been widely introduced for this purpose for the last decade. However, there is still lack of routinly application in agriculture. The main reasons are timeconsuming data processing and aqusition, particulary for multi-offset measurments. In order to fill this gap we tried to adapt single-offset measurment. Our field study contained several measurments for different time span after ground irrigation. We used 800 MHz shielded and 200 MHz unshelded antennas. We focused on ground wave which propagates just beneath the surface. We observed relative velocity and amplitude spectrum changes of air and ground waves after water irrigation. These changes has an explanation in electromagnetic wave propagation theory. Water irrigation causes the increase of ground wave time arrivals and shift of amplitude spectrum towards lower frequencies.
Effectiveness of reducing seismic hazard by means of group winning blasting - case study from a copper ore mine in Poland
Authors: Gogolewska Anna Barbara , Czajkowska Natalia
Published: November 2018

The copper ore deposit situated in the south-west of Poland is mined by three underground mines owned by KGHM Polish Copper JSC. Exploitation has been accompanied by rock burst hazard since the beginning. Thus, numerous different preventing measures have been developed such as temporary, organizational and long-term ones. However, no one has been able to predict the time, place and energy of a seismic event. The group winning blasting, with maximum number of blasted faces, is the most effective operation to reduce seismic threat. The more faces are blasted the more seismic energy should be reduced. The study aims at assessing the blasting effectiveness in inducing rock bursts and tremors. For this purpose, the seismic activity induced by mining and blasting were investigated. The number of blasting works and blasted faces as well as length of time between subsequent blasting works were analysed and related to provocation effectiveness. The linear correlation and different regressions were calculated to determine these relations. Moreover, the seismic energy reduction in the rock mass was evaluated by means of SRMS Index, which is a factor measured directly before and after blasting. The analyses covered one mine panel in the Polkowice-Sieroszowice copper mine over four-year period.
Comparison of the results of the seismic profiling and WAS-96/RMS seismoacoustic active method in an assessment of the impact of the overlying coal seam edge
Authors: Olechowski Sławomir , Krawiec Krzysztof , Kokowski Jakub , Szreder Zbigniew , Harba Paulina , Ćwiękała Mateusz
Published: November 2018

In the study, a comparison between the results of seismic profiling and the active seismoacoustic method WAS-96/RMS has been presented. The methods were used to assess the impact of an overlying coal seam edge on the relative stress state of the test heading in the chosen hard coal mine in the Upper Silesian Coal Basin, Poland. The work presents the methodologies of measurement, processing and interpretation of both methods. In the research area there were two edges of the adjacent seams at vertical distances of 70 and 100 m. The obtained results allowed for the development of conclusions regarding the effectiveness of both methods. It was stated, that the seismic profiling method, as well as the WAS-96/RMS method allowed for the identification of anomalies in the area of impact of the overlying coal seams. Based on previous experience, a comparison of the advantages and limitations of the seismic profiling and the WAS- 96/RMS method has also been presented. As a result, it was found that seismic profiling should be the basic method for assessing the impact of the edges and remnants of exploited seams, whereas the WAS-96/RMS method may be used as a complementary method if a confirmation of the rockbursts threat is required.
Slope stability monitoring in open pit mines using 3D terrestrial laser scanning
Authors: Bazarnik Miroslawa
Published: November 2018

In open pit mines the aspect of preventing and forecasting the threat of landslides and rock falls is crucial issue because of the significant consequences that instabilities may have. Systematic slope stability monitoring is necessary to ensure safe and continuous mining operations. The development of innovative technologies, such as 3D laser scanning, opens up new possibilities, especially in the case of large and hard-to-reach areas, such as open pit mines. Terrestrial laser scanners (TLS) provide fast, efficient, detailed, and accurate three-dimensional data. The article discusses the use of 3D terrestrial laser scanning method to monitor slope displacements and landslides in open pit mines. The first part of the article discusses the risk scale of gravitational displacement on the slopes, on examples of Polish open pit mines, and introduces the most common slope monitoring methods. Then, the principles of 3D terrestrial laser scanning were defined, and some examples of TLS applications in the open pit mines were presented.
The importance of pre-tensioning cable bolts used to reinforce of arch yielding support
Authors: Rak Zbigniew , Cieślik Jerzy , Stasica Jerzy , Dvořák Pavel
Published: November 2018

Widespread in Polish hard coal mining, cable bolts are used to reinforce the arch yielding support of roadways. This article attempts to prove that change in approach to long bolting technology can bring significant benefits in terms of improving the stability of roadways, including limiting the development of the fracturing zone in the roof, and ultimately also increasing the frame spacing of arch yielding support. The article contains the results of numerical calculations using the finite element method showing the effect of pre-tensioning on the work of cable bolts installed in a situation when a zone of a fractured rock mass appeared in a roof excavation. As a result of the calculations, the dependence of the final vertical displacements of the roadways roof on different pre-tensioning variants of the cable bolts was presented. The second part of the article presents the practical aspects of the use of cable bolts with pre-tensioning in reinforcing the rock mass and arch yielding support of roadways. In addition, the article identifies the developments in bolting technology which could lead to an increase in work safety and reduce the costs of arch yielding support.
Effect of initial seawater concentration on forming ice slurry for thermal energy storage in fishing vessel
Authors: Rayhan Fajri A , Yanuar  , Pamitran Agus S
Published: November 2018

Ice slurry technology has great potential in maximizing the chilling process of fish. Seawater is widely used as base solution of ice slurry due to Natrium Chloride content as freezing point depressant. In this study, effect of initial seawater concentration was investigated experimentally. The initial concentration of seawater was varied at 1, 1.5, 2, 2.5 and 3 wt%, respectively. Performance of systems and microscopic of ice particles were also observed. Ice slurry generated from 1 wt% seawater solution gives good agreement toward formation time of ice slurry. The diameter of particle ice increases with decrease in concentration. For application in thermal energy storage of fishing vessel, it is recommended to use low concentration of seawater.
Plasma electrolysis method for reducing COD in tofu wastewater
Authors: Pangestika Widya , Permatasari Nadira Kamilia , Saksono Nelson
Published: November 2018

Chemical Oxygen Demand (COD) is one of pollution parameter that have to be reduced so the wastewater may not harm the environment. Tofu wastewater is one of the organic wastewater that have high concentration of COD. The level of COD in untreated tofu wastewater outnumbered 8000 mg/L. This parameter could be lowered by plasma electrolysis that produced radical species to degrade pollutants in the wastewater. Three variations had been done in this study, such as: the addition of Fe2+ ion as a catalyst, the voltage, and the depth of anode. It was shown that addition of 60 mg/L of Fe2+ ion in plasma electrolysis could degrade COD in tofu wastewater to 73%. The effect of the voltage also had been studied. By using the voltage at 750 V could discard COD as much as 85%. The last variation that was conducted in this study is the effect of the depth of anode in plasma electrolysis. The result showed that 73% of COD in tofu wastewater could be reduced by using the depth of anode 2 cm. All of these results showed that plasma electrolysis is a potential method to degrade pollution parameter, especially COD in tofu wastewater.
Design of Arduino-based small wind power generation system
Authors: Al Mubarok Abdul Goffar , Djatmiko Wisnu , Yusro Muhammad
Published: November 2018

Wind energy is a less-attended renewable energy due to the lack of information about its potential. Some pilot wind turbines were not managed properly and built without considering to the technical feasibility. This study aims to propose a preliminary design of an Arduino-based small wind power generation system. The electricity which is generated by the wind charges the battery. It supplies power of information system which transmits the data of wind speed and wind direction from the remote location to the web server through GPRS network. The remote location which is completed with mobile data coverage is essential for this study. The results of this study are (1) the battery charging stop automatically when the battery is full (2) the data of wind speed and wind direction can be accessed through web browser or Android Smartphone. The data can be used for further analysis to determine the potential of wind energy at the site.
Investigation of Flow Characteristic on Ram Pump in Different of Pipe Junction Geometry
Authors: Mardikus Stefan , Wihadi Dwiseno , Maryanto
Published: November 2018

Ram Pump is a mechanical device that uses phenomenon of difference pressure to distribute the water toward high state level. The advantages of ram pump are low cost, construction of reliable and without electrical energy. Kinetic and potential energy are main factor to flow the water in driver pipe. This research purposed to determine flow characteristic in different geometries of ram pump based on experiment data. Ram pump operated on different pressure of inlet area which was get from water level. To get the flow characteristic of rum pump, it was simulated using computational fluid dynamic. The result of simulation was found that junction type of U shape appeared wake in driver pipe area; thus, this phenomenon indicated any turbulent flow because decreasing of pressure. In other junction pipe, wake phenomenon appeared in driver and delivery pipe area.
Reduction of COD and BOD concentration in lake water of universitas indonesia with microbial desalination cell system and utilizing bio charcoal as electrode
Authors: Istiqomah Hidayati , Puspitarini Putri Anggun , Ekadewi Putty , Utami Tania Surya , Arbianti Rita , Hermansyah Heri
Published: November 2018

One of the most promising areas with the existence of the lake is Universitas Indonesia. Universitas Indonesia (UI) has six lakes with a total area of 269,107 m2 which is very important for its existence to balance the surrounding environment. Currently, the existence of UI lake has been contaminated with the COD value of about 1 to 8.000 mg/L due to a lot of garbage that enters and buried in it, that more attention is needed so that pollution will not increase. Microbial Desalination Cell (MDC) is a development system of Microbial Fuel Cell (MFC), which has the ability to desalinate seawater and can produce electricity by using microorganisms as waste decomposers. In addition, MDC method can also reduce the level of waste contained in the substrate used. To improve the performance of MDC, this study utilizes bio charcoal from rice husks to assess the performance of sodium percarbonate in the cathode chamber with a variation of 0.05 M concentration; 0.1 M; 0.15 M; and 0.2 M, and the performance of the addition of bacteria consortium on the substrate. The best results of this MDC study, in the variation of 0.15 M sodium percarbonate concentration with a decrease of COD and BOD of 93.98% and 87.67% and in variation of addition of bacteria consortium of 1 mL with decrease of COD and BOD 90.04% and 50.52%.
Degradation of Remazol Brilliant Blue Using Plasma Electrolysis Method with NaCl and Fe2+ Ion Addition
Authors: Saksono Nelson , Zairin Dwiputra Muhammad , Averous Fikri
Published: November 2018

Remazol Brilliant Blue is a dye waste mostly generated by the textile industry and can be very dangerous to the environment. Plasma electrolysis is a method that can produce hydroxyl radicals in large quantities in order to degrade the dye compounds. This study aims to test the ability of plasma electrolysis method to degrade Remazol Brilliant Blue wastewater using NaCl as electrolyte, with the addition of Fe2+ ion and air injection. Before the degradation process was carried out, permanganometric test was performed to see the production of hydroxyl radicals with the variations of electrolyte concentration and voltage. The degradation process were investigated more specifically by looking at the effect of Fe2+ ion concentration and the initial concentration of Remazol Brilliant Blue. Remazol Brilliant Blue degradation reached 98.5% in 30 minutes where the initial concentration of Remazol Brilliant Blue is 100 ppm, voltage of 750 V, NaCl concentration 0.03 M,with the addition of 40 ppm Fe2+ ion and air injection. The results show that plasma electrolysis with NaCl as electrolyte using air injection has a good potential in degrading dye wastewater in the environment.
Development of semi-integrated solar street lamp for rural area
Authors: Abuzairi Tomy , Devara Kresna , Rezky Ananta , Bastian Andrew , Wing Wira A.R. , Udhiarto Arief
Published: November 2018

A solar street lamp is a lamp technology that utilizes solar cell to obtain electrical energy during the daylight hour by solar radiation and then use the electrical energy to provide light at night. Semiintegrated lamp tries to overcome complicated installation and expensive price of normally solar street lamp. Semi-integrated solar street lamp only integrated solar cell, controller, and battery, while lamp is separated using cable. This configuration makes semi-integrated lamp cheaper and easier for installation that is suitable for rural area. Therefore, in this paper we develop semi-integrated type of solar street lamp. The illumination of semi-integrated lamp was measured using lux meter. The power of the lamp was calculated to meet the energy needs for 12 hours. The results show that the semi-integrated solar street lamp with low power LED ~2W has been successfully developed. The solar lamp can be automatically turned on for around 12 hours, from 5:50 PM to 5:31 AM (UTC+7). The illumination average of the lamp is 17.42 lux with 6.97 lux deviation. The measurement result of illumination shows that the solar street lamp has maximum distance of more than 140 cm with 230 cm high of lamp.
Characteristic Analysis of Photovoltaic On-Grid System In Tropical Region For Weather-Corrected Performance Ratio Calculation Method Implementation
Authors: Syahputra Erfan , Fajarin Rio Agustian , Setiawan Eko Adhi
Published: November 2018

Indonesia has different weather factors than the subtropical climate that influences the performance indicators of photovoltaic systems. One of them is performance ratio that is affected by temperature factors. NREL proposes calculation method of Weather-Corrected Performance Ratio for correcting factors (temperature) in calculation performance ratio of photovoltaic systems. However, the implementation of this method in real operating condition of photovoltaic system especially in the tropics, has not received special attention. In addition, temperature coefficient of power photovoltaic (δ) in Standard Test Condition, is used in the calculation method may be different in real operating condition. This study was conducted to determine the effects of weather-corrected performance ratio method and to know characteristic of temperature coefficient of power photovoltaic (δ) as factors in of weather-corrected performance ratio method, in real operating condition especially in tropics. Through analysis photovoltaic system data from the data logger it is found that the range values of weather-corrected performance ratio are greater than conventional methods, with a maximum increase of 2.43%. Moreover it is found that because average temperature of tropical climate is higher than subtropical climate, it makes the percentage of power decrease to rise in temperature (δ) in tropical climate is higher than subtropical climate.
Cost estimation model in early stage of design through implant miniplate complexity process index
Authors: Budiono Hendri D.S. , Lassandy Marthan
Published: November 2018

Manufacturing is an activity of processing raw materials into semi-finished or finished products. In addition to manufacturing process, the industry needs product design, material selection, material distribution to create a product. A product produced from a manufacturing system has an index of product complexity that illustrates that the product is made with a certain degree of complexity. The process done on the production of miniplate implants is the process of forming an outside profile, slicing process, the hole process, micro finishing, and ultrasonic cleaning. Quantitative methods used are feature-based cost, operationbased cost, and breakdown approach. Feature based cost consists of cost by feature, that is the cost outside profile, slicing process, the hole process, micro finishing, and ultrasonic cleaning costs. Operation based cost consists of set up, operation, and unloading costs. Breakdown approach consists of cost set tool, set workpiece, and programming on set up, operator cost, material, overhead, energy, and tool, unloading cost consists of release tool cost and release workpiece. Process complexity of the miniplate implant manufacturing process in the early stage of the design can be done with the help of Siemens Nx 8 software as a timing guide with the same parameters and has been tested for the correlation. The process complexity index of the miniplate implant manufacturing process is 100.08 and the estimated process cost of the miniplate implant manufacturing process using a combined analytical technique is IDR 139.150,94.
Palm Oil Mill Effluent (POME) utilization for bio-hydrogen production targeting for biofuel : optimization and scale up
Authors: Prasetyo Joni , Sumbogo Murti S.D. , Senda Semuel Pati , Latief Andi Djalal , Dwi Husodo Prasetyo R. , Hastuti Zulaicha Dwi , Yanti Fusia Mirda , Juanda Firdaus , Permana Edwin , Muis Lince
Published: November 2018

Indonesia is the largest palm plantation that reaches 32 million tonnes palm oil production per year with 84 million tones Palm Oil Mill Effluent (POME) as liquid waste. POME contains many organic substances. The quality of POME for its utilization is generally measured in COD which has range 30000 -100.000 ppm. Microbial convertion for biogas especially for bio-H2 enrichment, the active sludge was pretreated physically to suppress methanogenesis microbes. H2 Biogas production was conducted at pH 5-6. Additional 10% phosphate buffer was done in the beginning only. The production of H2 biogas was influenced by hydrostatic pressure in closed batch system. Inoculumsmedium ratio also influenced the H2 biogas productivity, reached 0.7 ml/ml POME with more than 50% H2. Scaling up anaerobic in 2.5 L working volume bioreactor, H2 biogas productivity reached 0.86 ml/ml POME by 10% inoculums because of no hydrostatic pressure. In bio-reactor, H2-CO2 in H2 biogas was affected by the amount of active sludge. In the beginning of H2 biogas, H2 reached 80%. However, at subsequence process, fed batch, with retention time 2.5 day and 3 days H2 biogas production, the active sludge was accumulated and caused the decreasing H2, finally only 46% at the 3rd day. The consortium tended to produce more CO2 as the result of primary metabolite rather than H2. Raising inoculums to level 15% improved productivity only in the beginning but H2 content was getting less, only 59%. Additional feeding would cause more accumulation sludge and more decreasing H2 content to 31% on the 3rd day. Thus, the ratio of active sludge and substrate availability must be controlled to gain optimum H2. Limited substrate will cause the direction of bio-conversion more in CO2 rather than H2.
Study of the use of nanomaterials as drilling mud additives
Authors: Kusrini Eny , Suseno Bayu , Khalil Munawar , Nasruddin  , Usman Anwar
Published: November 2018

Previous research on drilling mud concludes that oil-based mud is the best drilling fluid, but is not recommended because it is unsustainable and environmentally unfriendly. Therefore, research has been conducted on additives that can be used for water-based mud, making it equal or even superior in quality to oil-based mud. The use of graphene as a drilling mud additive may form mud cake as a filtration barrier, and the use of magnesium oxide (MgO) may increase the viscosity value. Rheological analysis is conducted using the Bingham plastic method, a simple method generally used in the oil and gas fields, whereas use of the Power Law model can provide better modelling of Bingham plastic that cannot be achieved for well under surface analysis. Tension limit simulation was performed to determine the safe limits of the tool's ability to withstand loads. Control of equivalent circulation density (ECD) is very important; if this is too high it can cause loss of circulation, and if too low it can cause kick. In Bingham plastic, the value of plastic viscosity and the yield strength of the graphene additive increased by 25 and 32%, respectively, compared to the base formula. The MgO yield strength value is too high, indicating that MgO cannot be used as a drilling mud fluid additive. In graphene oxide (GO) additives, there is a decrease in plastic viscosity of 50% and an increase in yield strength of up 180%. The graphene torque limit value increased by 0.2% and the drilling depth increased by 2.8% compared to the base formula. The GO torque limit value increased by 0.2% and the drilling depth increased by 2.08% from the base formula, while the tension limit of the graphene additive increased by 38.8% from the base formula and on the GO decreased by 2.11%. From the ECD simulation, graphene is more suitable for wells with high formation pressures, GO is more suitable for low pressure wells.
Biogas-fuelled Stirling engine for electric power generation
Authors: Yatim Ardiyansyah , Luthfi Ade , Chemilo Raden
Published: November 2018

The Stirling engine is an external combustion where the fuel combustion process takes place outside the cylinder. It offers flexibility of fuel used for the power generation, hence is a potential substitute to fossil fuelled internal combustion engine and contribute toward more sustainable power generation. In this study a Gamma V2-6 Stirling engine is used in a biogasfuelled power generation system. The engine has maximum capacity of 10kW. The required fuel input is 60,000BTU/hr or equivalent to 17 kW. The fuel is a biogas which comes from a biodigester. The system requires constant heat from the combustion chamber, hence a novel fuel distribution control is introduced. A specific burner is also designed to fulfil the purpose. In this study, a biogasfueled Stirling engine for electric power generation is designed and developed. The system has 5 kW capacity fuelled by 165 kg/day solid waste (biowaste) from local farm. The biodigester needed is 20 m3. Based on empirical model, the estimated energy efficiency of the system is 36%. In addition, the system offers potential utilization of hot water as by side product.
Utilization of crown pineapple waste as raw material preparation of activated carbon as adsorbent in natural gas storage
Authors: Yuliusman  , Nasruddin  , Naf’an H I , Sinto J , Nugroho Y W
Published: November 2018

Activated carbon used as natural gas storage in adsorbed natural gas technology due to physical adsorption properties. Pineapple crown was used as raw material for activated carbon by reason of high lignocellulose content. The purpose of this study is to produce high surface area of activated carbon with high carbon composition (up to 80% weight). Activated carbon were prepared through chemical activation using KOH with various weight ratio and physical activation using N2 with 150 ml/min flowrate. Carbonization of pineapple crown is done at 350°C followed by chemical activation with KOH activator and physical activation. The result of iod number indicate the 1:1 weight KOH ratio gave the highest iod number 1337 mg/mg and 1190.799 m2/g surface area achieved by chemical-physical activation.
Simulation of a bioavtur production process from non-edible vegetable oil
Authors: Alimin Achmad Anggawirya , Susanto Bambang Heru
Published: November 2018

The increase in global aviation fuel demand has prompted ICAO to declare neutral carbon growth policy in 2050 by using bio based aviation fuel. The purpose of this study was to simulate the production of non-edible vegetable oil into bioavtur and obtain the most potential nonedible vegetable oil based on yield and conversion to be converted into bioavtur. Three potential sources to be converted into bioavtur are kosambi oil, nyamplung oil and kemiri sunan oil. This research was done by simulating of the hydroprocessing process with process simulator by varying the operating conditions on each raw material. Hydrotreating process was varied at 1-5 MPa pressure and temperature 250°C-350°C. The result showed the operating pressure with the highest conversion and yield are around 4MPa. While the operating temperature with high conversion and yield are above 290°C. Nyamplung oil has overall the largest yield and conversion than other nonedible vegetable oil with average 10% greater conversion and 3,3% greater yield at 2MPa.
Sythesis of bioavture through hydrodeoxygenation and catalytic cracking from oleic acid using NiMo/Zeolit catalyst
Authors: Carli Michelle Flavin , Susanto Bambang Heru , Habibie Thareq Kemal
Published: November 2018

Currently, fossil fuels are still the primary source of fuel. As has been known, fossil fuel especially aviation fuel is limited resources and can increase greenhouse gas emissions. This condition encourages replacement efforts of avture into bioavture fuel. In this research, bioavture is synthesized through hydrodeoxygenation and catalytic cracking from oleic acid as a model compound using NiMo/Zeolite catalyst. Hydrodeoxygenation carried out under operating conditions: at temperature of 375°C, under 15 bar pressure and for 2.5 hours. The chain of hydrocarbons from the result of hydrodeoxygenation has been cracked by catalytic cracking reaction for 1.5 hours. Variation operating condition used are 360, 375, and 390°C. The liquid product is tested its chemical characteristic, ie acid number, FTIR and GC-MS and its physical characteristics, ie density test and viscosity. Bioavtur that synthesized by catalytic cracking have met the specifications of bioavtur, except the acid number with optimum temperature at 375oC. These conditions with NiMo/Zeolite activated led to dominant yield of 36.32%, selectivity of 38.05%, and conversion of 84.30%. Percentage of yield and selectivity of bioavtur are still low caused by performance of catalyst that is still can not optimum. While, high percentage of conversion caused by high temperature used for catalytic cracking.
Producing monoaromatic compounds from pyrolytic vapour of rice straw using H-ZSM-5/B2O3catalyst
Authors: Setiadi  , Wijaya Raka Nugraha , Pradana Danestyan Arif
Published: November 2018

The catalytic conversion of rice straw was done to produce mono aromatic compounds. The mixed catalyst of ZSM-5 and B2O3was obtained through calcination of ZSM-5 and H3BO catalyst mixture. The variation of the composition of the ZSM-5 and B2O3 catalyst was applied in order to test the effect of catalyst composition to the production of mono aromatics compounds. The composition of catalyst used were 15% ZSM-5, 30% ZSM-5, and 100% ZSM-5. Other than the variation of catalyst composition, the variation of the operating temperature of the catalytic conversion also performed in order to study the effect of the temperature to the production of mono aromatic compounds. The catalytic conversion was done at 450, 475, and 500 oC. Experimental results show that the addition of the catalyst resulted in the conversion of oxygenate compounds resulted from the pyrolytic process of rice straw into mono aromatic compounds. It also shows that using 100% ZSM-5 produced the highest yield of mono aromatics compounds. The amount of mono aromatic compounds produced will decrease, as the fraction of ZSM-5 catalyst used and operation temperature also decreased. Using the 100% ZSM-5, the mono aromatics compound with the highest yield is 1, 3 Dimethyl benzene or mxylene.
Co-pyrolysis of corn cobs and polypropylene for production of biofuel similar to gasoline at low heating rate
Authors: Supramono Dijan , Utomo Fianna , Setiadi  , Nasikin Mohammad
Published: November 2018

Co-pyrolysis between corncobs and polypropylene has a synergetic effect that transforms part of polar fraction of bio-oil into non-polar fraction containing non-oxygenate compounds as precursor for synthesis of bio-fuel. In the present work, pyrolysis of the nonpolar fraction of bio-oil was led to produce bio-oil with viscosity similar to that of gasoline and contained non-oxygenated compounds. The pyrolysis was carried out in 2 stages, where the first-stage was co-pyrolysis to produce non-polar bio-oil and the second-stage was pyrolysis of non-polar fraction from the first stage to reduce its viscosity similar to that of gasoline. The first and second-stage pyrolysis was carried out in a stirred tank reactor at heating rate of 5˚C/min using nitrogen as carrier gas with the second-stage pyrolysis final temperature varied. The resulting bio-oil product was characterized by FT-IR, GC-MS, H-NMR, viscometer and LC-MS. The results show that bio-oil viscosity and yield of the second-stage pyrolysis heavily depended on its final temperature, in which the higher the temperature, the higher was the viscosity, yet the higher was the bio-oil yield. Final temperature of 300°C was the optimal one for obtaining bio-oil similar to gasoline regarding its close viscosity despite of low yield of bio-oil. Pyrolysis of bio-oil may be performed coinciding with attempting of reducing branching index to reduce its viscosity.
Hydrogenation of non-polar Fraction of Bio-oil from Co-pyrolysis of Corn Cobs and Polypropylene for Bio-diesel Production
Authors: Supramono Dijan , Edgar Justin , Setiadi  , Nasikin Mohammad
Published: November 2018

Bio-diesel was synthesized by hydrogenating the non-polar fraction of the bio-oil produced from the co-pyrolysis between corncobs and polypropylene. Co-pyrolysis of corn cobs and polypropylene was conducted in a stirred tank reactor at heating rate of 5°C/min and maximum temperature of 500°C to attain synergetic effect in non-polar fraction yield where polypropylene served as a hydrogen donor and oxygen sequester so that the oxygenate content in the biofuel product reduced. Stirred tank reactor configuration allowed phase separation between non-polar and polar (oxygenate) compounds in the bio-oil. Hydrogenation reaction of the separated non-polar phase, which contained alkenes, was carried out in a pressured stirred tank reactor using a NiMo/C catalyst in order to reduce the alkene content in the bio-oil. The aim of the present work is to reduce the alkene content in the separated non-polar fraction of bio-oil by catalytic hydrogenation to obtain biofuel with low alkene content and viscosity approaching to that of diesel fuel. To quantify effect of the pressure on the alkene composition, the experiment was done at H2 initial pressures of 4, 7, 10, and 13 bar and at corresponding saturation temperatures of octane. The biofuel products were characterized using GC-MS, LC-MS, FTIR spectroscopy, H-NMR, Higher heating values (HHV) and viscometer for comparison with those of commercial diesel fuel. Analysis of the lower molecular weight fractions of biofuels by GC-MS found that the hydrogenation reactor at pressures at 4 and 7 bar produced biofuels with predominant hydrocarbon contents of cycloalkanes and alkanes, while that at 10 and 13 bar produced biofuels with predominant contents of alkanes and alkenes. In comparison, diesel fuel contains mostly alkanes and aromatics. However, analysis over the whole content of bio-oil by H-NMR found that different pressures of reactor hydrogenation did not reduce alkene compositions in biofuels appreciably from alkene composition in bio-oil feed. In comparison, diesel fuel contained mostly alkanes with aromatic composition about 4% and no alkene content. Various data suggest that alkene content in the biofuels be reduced to approach their viscosity to that of diesel fuel. Modification of the hydrogenation reactor is required by improving convective momentum of hydrogen gas into the bio-oil to enhance contact of solid catalyst, hydrogen gas and bio-oil.
Characteristic of Gasoline Fuels in Indonesia Blend with Varying Percentages of Bioethanol
Authors: Sugiarto Bambang , Setyo Wibowo C. , Zikra Ardi , Budi Alva , Mulya Try
Published: November 2018

Indonesia has The National Energy Policy based on the principle of fairness, sustainability, and environmentally friendly, and the creation of national energy security. Start from early 2015, mandatory of using biofuel as a substitution to fuel or blend on subvention fuel, nonsubvention fuel, industrial, commercial, and power plant sector is implemented by the Government of Indonesia on Ministerial Energy and Mineral Resources Regulation 12/2015. As a biofuel, bioethanol can be used as a fuel substitution for gasoline. Bioethanol is a natural product and manufactured by the fermentation of plants containing sugar and starch. Characteristic physical and chemical of bioethanol near to gasoline. The objective of this research was to determine the effect of bioethanol-gasoline blended fuels on the characteristic physical and chemical. The experimental test was using gasoline with octane number 88, 92, 98, and 5%, 10%, 15%, 20% bioethanol blend. The effect of the bioethanol-gasoline blend on physical and chemical properties is increased research octane number, oxygen content, vapor pressure, and to decrease the heating value. The one of the important parameter for combustion process on gasoline 88 is the final boiling point temperature, with bioethanol blend of 20% can decrease 7% of the final boiling point value.
Performance of Palm Oil Mill Effluent (POME) as Biodiesel Source Based on Different Ponds
Authors: Leela Deodata , Nur Syukri M. , Yandri Erkata , Ariati Ratna
Published: November 2018

The purpose of this paper is to prove that waste palm oil industry (POME) can be used as raw material (source of energy) for biodiesel. In the production process, palm oil mill produced large amounts of waste. The provision of a shelter pond system is a temporary solution from palm oil mill to relocate the liquid waste. With BOD content with range 25,625 to 39,616.7 mg/l and COD content with range 117,333.3 to 146,333.3 mg/l, this condition will generate a serious problem for environmental pollution. Therefore, it is important to test the characteristics of waste oil from each pond. The hexane solvent extraction method is used to separate the oil from the liquid waste. The first pond contains 51.3% water, 21% oil, 2% sludge & sediment and 5.6% free fatty acids. The second pond contains 86.7% water, 16.1% oil, 2.4% sludge & sediment and 8% free fatty acids. The third pond contains 74% water, 6.8% oil, 3.1% sludge & sediment and 12.2% free fatty acid and the fourth pond contains 78.7% water, 3.7% oil, 2% sludge & sediment and 13.3% free fatty acids. Based on the results of this research, the characteristics of POME and its oil losses are the fraction of oil wasted from Crude Palm Oil (CPO) processing, whereas CPO has characteristics as a raw material for Biodiesel. POME should be processed into biodiesel since the liquid waste is discarded from palm oil mill, so there is no need a big land to make waste storage ponds.
Designing Smart Energy System for Smart City through Municipal Solid Waste to Electricity: Techno-Economic Analysis
Authors: Octavianthy Desti , Purwanto Widodo Wahyu
Published: November 2018

Smart energy system is one of the important infrastructures for building smart city. Waste to energy (WtE) is an innovative solution using municipal solid waste (MSW) as a source for electricity. This research was conducted to design WtE Plant in Depok and to asses economic viability of different business models. The technologies applied in WtE are anaerobic digestion and gas engine to generate electricity. The simulation was conducted using SuperPro Designer and UniSim Design software to evaluate the technical performances of electricity production from organic solid waste. The feasibility of project implementation of various business models are evaluated through economic analysis. The result of this study shows that the organic fraction of municipal solid waste in Depok has potential to generate electricity up to 28 MW. From economic aspect, pay off business scheme greatly affects the value of NPV and IRR. Meanwhile, the intervention scheme on fiscal incentives and low loan interest rate have slight effect on IRR values. A combination of Viability Gap Fund (VGF) and increased tipping fees intervention scheme is an optimum business scheme to build WtE plant and achieve electricity price below the offtaker’s willingness-to-pay.
Catalytic hydrogenation of straight vegetable oil using NiMo/ Al2O3 catalyst for biodiesel production
Authors: Sumbogo Murti SD , Prasetyo J. , Murti G.W. , Hastuti Z. D. , Yanti F. M.
Published: November 2018

The attractiveness of biodiesel as an alternative fuel compared to fossil fuels because it has many advantages such as the availability of abundant raw materials, more environmentally friendly, high combustion efficiency, low sulphur content, high cetane number and biodegradability. Making biodiesel from straight vegetable oil (VGO) has been done through the catalytic hydrogenation process. A VGO of callophylum inophyllum oil was treated via degumming and neutralisation to remove all impurities before hydroprocessing. Hydroprocessing was carried out in a 500ml autoclave at 30 – 50 MPa of initial hydrogen pressure, 300 – 400oC of reaction temperature and equipped with stirrer and cooling system. NiMo/Al2O3 catalyst was activated with CS2 mixture at 370oC prior to the reaction. Some physical and chemical properties of the catalytic hydroprocessing product have been investigated in accordance to ASTM standard. The measurement result of product varies according to the operation condition. The result showed that callophyllum inophyllum oil can be used as raw material for biodiesel production over NiMo/Al2O3. Sulfided NiMo/Al2O3 catalysts are preferred due to high diesel yield.
Multi objective optimization of microalgae flat plate photobioreactor design
Authors: Rahman Arif , Nasution Sanjaya BS , Siregar Sri RH , Nasruddin
Published: November 2018

Indonesia as a maritime country has high potential in developing microalgae. Microalgae in Indonesia have a high oil component of around 20-30%, for example Nitzschia palea (23%), Chlorella vulgaris (27%), and Euglena gracilis (20%). In addition to biofuel production, the microalgae species chlorella vulgaris can also be used as part of wastewater treatment. This paper aims to optimize the photo-bioreactor design for microalgae with multi-objective functions including exergy and economics. One method used is the Multi-Objective Multi-Verse Optimizer (MOMVO). MOMVO optimization is related to several objective functions with specified constrain. Objective functions and constraints will be resolved in the form of algorithmic functions. From the optimization results using the Multi-Objective Multi-Verse Optimizer (MOMVO), it can be concluded that the optimum exergy value is at 1292.5 cd and the pressure is 3.34 kPa with an exergy destruction value of 23,424.96 kW and a total cost of $ 42,744.85. While the optimum economic value is at 1292.51 cd and the pressure is 3.34 kPa with an exergy value of destruction of 23,726.82 kW and a total cost of $ 42,837.36.
Toolpath strategies and management to optimize energy consumption on 3-axis CNC milling machine
Authors: Kiswanto Gandjar , Poly Poly , Johan Yolanda Rudy
Published: November 2018

CNC milling machine is a production machine which widely used to manufacture many kinds of products. In the process of milling machining, the time needed to produce a component must be as minimum as possible to minimize the costs and its impacts on the environment. One of energy consumptions used in CNC milling machines is to supply electric motors for each axis of motions. Cutting energy consumption can be minimized by optimizing the cutting parameters, such as the cutting toolpath. Modelling and comparing the total energy consumption of the cutting process from different cutting toolpaths and strategies are important in selecting the right toolpath that has the smallest energy consumption. To achieve this goal, this study models the energy consumption during the cutting process. The model is then used to evaluate and compare different cutting toolpaths from different cutting strategies. Three prismatic and one sculptured part were used to examine the model of cutting energy consumption. A Graphical User Interface is also developed to simplify the comparison and evaluation process. Through this process it will be possible to predict energy consumption in the cutting toolpath and hence enable the selection of the right toolpath to reduce energy consumption in machining.
Experimental study on utilization of heat pipe heat exchanger for improving efficiency of clean room air system in hospitals
Authors: Hakim Imansyah Ibnu , Putra Nandy , Marda Adam Prihananda , Alvaro Muhammad Alvin , Winarta Adi
Published: November 2018

Heating, Ventilation, and Air Conditioning (HVAC) system in hospital's clean room is required to continue working for 24 hours to provide the ideal air quality for the activities therein. This causes a huge amount of energy consumption in hospital buildings itself. This study aims to determine the effectiveness and heat recovery of Heat Pipe Heat Exchanger (HPHE). The HPHE used in this study consisted of 12 heat pipes per module, in which the line was arranged staggered. The number of the module is varied 3 times, which are 1, 2, and 3 modules. The heat pipe is made of copper and contains working fluid in the form of water with 50% filling ratio. HPHE equipped with fins to expand the contact surface with airflow. Each variation of the number of modules is tested on the HVAC system model of the clean room. In the evaporator inlet, air flowing to the variation of temperature: 28, 30, 35, and 40°C, and at speeds of 1.5, 2.0, 2.5 m/s. The use of HPHE can recover heat as much as 1654.72 kJ/h. The highest effectiveness of this HPHE is 48.729%, was obtained when using three modules, air temperature inlet evaporator (Te,i) = 35°C, and airspeed of inlet 1.5 m/s.
Output voltage characteristic in system lighting road based on heat pipe and thermoelectric
Authors: Septiadi Wayan Nata , Murti Made Ricki , Arliyandi  , Pristha Arvikadewi I.G.A. , Putu Yuda Pramana Putra I
Published: November 2018

A novel design of a thermal management pavement system is introduced in this paper. The basic concept behind this design is a utilize of waste heat from asphalt pavement have as a base a heat pipe and thermoelectric for energy of street lighting. In this system, output voltage is influenced by difference in temperature between hot side and cold side of thermoelectric. The intensity of solar radiation at hourly is variant, so the resulting of output voltage fluctuated. The research method by field testing direct exposed solar radiation on the variation time at 09.00; 10.00; 11.00; 12.00; 13.00; 14.00; 15.00; 16.00 Indonesia Central Standard Time. The data of this research are surface temperature of asphalt pavement, difference in temperature between hot side and cold side of thermoelectric, and output voltage of system. The analysis process by quantitative experimental. In this research, the output voltage increased from 09.00 until 13.00, and after that time the output voltage decreased.
Study of microfine cement use on squeeze cementing operations in plug and abandonment work
Authors: Asyri Muhammad , Mulia Kamarza
Published: November 2018

The purpose of this study is to develop guideline and decision tree for selecting proper material of squeeze cementing operation as part of permanent well abandonment project in PT XYZ. The existing guideline in oil and gas industry does not cover the detail of cement type selection prior to do squeeze cementing job and this may cause failure in the operation and give the high cost impact due to remedial job. It is expected that the result of decision tree and guideline in this study can be used as a reference for plug and abandonment project in. The method used in this research is by calculating the value of the injectivity factor obtained from field study as a key factor in determining the type of cement for squeeze cementing operation. If the injector factor value is less than 2000 (<2000), it is concluded that G type cement (G class cement) is preferred to be used to isolate the reservoir formation zone. While for the injectivity factor value more than 2000 (> 2000), the reservoir is considered as tight formation and difficult to penetrate, so the use of microfine cement is expected to isolate the reservoir formation zone.