bluuebunny/crossref_metadata_2025_split huggingface dataset:
Series and parallel relationship pump performance in FT. Unitas’s practicum tools
Authors: Intang Ambo , Dwipayana Hendra 
Published: November 2019

Abstract
Basically, the variation of the pump arrangement in the piping installation is done to get the performance / flow characteristics needed in a particular usage according to the needs, namely the need for a head height that is higher than the flow rate (capacity) or vice versa. Flow regulation method with variations of valve openings (Senen 2004), which is applied in this study with consideration of energy use efficiency, it can be stated that the pump efficiency range of the parallel circuit is high to get a larger flow rate than the series circuit pump. To get the head maximum, the pump efficiency series is smaller than the pump efficiency of the parallel circuit, so that it does not provide an illustration that the optimum pump work has been achieved, so that further research needs to be carried out research with variations in pump rotation (Mastur and Warso 2015) below or above the standard round. But based on the purpose of this study in terms of pump performance, to meet the needs of a high head, the pump installation is arranged in series and vice versa if what is needed in the pump installation system is a high flow rate, the pump is arranged in parallel, so the results of this study have been can meet the needs of practicum for students of Mechanical Engineering Study Program FT. Unitas in terms of how to get the performance of a centrifugal pump installation.
The prediction of fatigue crack growth of rotary kiln shell welded under cyclic loading
Authors: Basri Hasan , Yani I , Yanis M , Prakoso A T 
Published: November 2019

Abstract
In this paper, fatigue crack propagation in the kiln shell welded under cyclic loading has been estimated using computerized finite element analysis (S-Version FEM). By using the S-FEM technique, it makes the local mesh which is re-meshed automatically, then it becomes easier to make a numerical study of crack growth on the welded kiln shell. Virtual crack closure integral method (VCCM) uses the stress intensity factor evaluated. From the results, it was observed that the crack depth grows faster as the number of cycles increased. It was found that the initial crack of welded shell propagates slowly, and beyond 8 × 105 cycles increase quickly. In addition, the effect of stress distribution and stress intensity factor on cracking have been discussed and evaluated. The life of the component depends on the initial crack depth, stress intensity factors and crack inclination angle.
The analysis of the dimple arrangement of the artificial hip joint to the performance of lubrication
Authors: Basri Hasan , Syahrom A , Ramadhoni T S , Prakoso A T , Ammarullah M. I. , Vincent  
Published: November 2019

Abstract
Artificial hip joint surgery is one of the most successful methods used to restore the functioning of damaged hip bones. But there are obstacles to the use of artificial hip bone, which is the amount of friction occurring and wears. To overcome these obstacles, a surface of the artificial hip joint is modified by adding dimples in order to minimize the contact pressure of solid and to reduce friction and wear. The purpose of this study is to determine a better of lubrication performance with the variations of the dimple arrangements under the normal walking condition. Simulation results have already exited the point of convergence studies, and the obtained results are such as hydrodynamic pressure, contact pressure, and the film thickness of the lubricant with the variations of the number and pitch dimples. The results of the CSM method under dry condition, it shows that the addition of surface with dimples has a positive effect to reduce the contact pressure and indirectly reduce wear. The maximum surface contact pressure is 54.84 MPa with dimple and 94.22 MPa without a dimple. The results of the FSI method under lubrication condition, it was found that the variation of 7 dimples with a dimple pitch of 500 μm has the best lubrication performance. The hydrodynamic pressure is 0.73 Pa, the contact pressure is 0.42 Pa, and the film thickness of the lubricant is 29.59 μm. The increase of film thickness that occurs due to hydrodynamic pressure will cause the fluid lift force to withstand the loading of the solid structure.
Parting control on coal seam quality based on ash content and total moisture, North Musi Rawas, South Sumatera
Authors: Putra Jefri 
Published: November 2019

Abstract
In its utility, coal is measured by how much the quality values contained inside such as ash content and total moisture. One of the factors that affect the value of coal seam quality is the existence of partings. Partings is an inorganic material that is formed in coal syn-depositional. Therefore, this study aims to identify the extent influence of the presence of the parting layers that in comparison of the laboratory test results from two sampling techniques. The application of the methods used was channel sampling where the coal sample was taken without partings and include partings. Coal seam thickness become the object of the research was 9.01 m with the presence of the four partings that have a thick layer of 6-8 cm. Comparative laboratory test result show ash content include partings more bigger than without parting with a difference of 2.7% adb. Deviation ash content the most indicated on ply 5. Suggesting parting layer has form of tuffaceous sandstone. Characteristic tuff is a volcanic deposits contain a high fly ash thus increasing ash content. While the total moisture include partings more smaller than without partings with a difference of 0.3% ar, It was suggested that partings just control the ash content, this is due to the type and character of lithology parting.
Late neogen deformation of rock successions at Renah Gajah Mati I Region Seluma Regency in Bengkulu
Authors: Zuhri Wahidin , Sutriyon Edy 
Published: November 2019

Abstract
Studies on tectonic deformation of the Late Tertiary sequence during Late Neogene time has been carried out at the Renah Gajah Mati I region using balancing and restoring techniques, kinematic and dynamic analyses. The Late Neogene deformation was mainly controlled by compression, which has resulted in folding and thrusting. Hence, the rock sections underwent shortening that varied from 1.42-1.83 km or 0.75%-0.78% with the estimated rate of deformation 0.12-0.15 mm/year. Two types of tectonic structures developed within the region, fault propagation folds and trishear faults. The brittle deformation extended sequentially in the direction of tectonic transport, resulting in a series of faults. The generated faults constitute imbricate fans with a relatively closely-spaced thrust system. The array of thrusts is apparently associated with folds that strike NW-SE, implying the geometry of fault-linked folding. The hanging wall anticlines are generally asymmetric overturned folds, indicating a shallow ramping fault with a high shear pattern. In regional context, the general strike of structures within the study area appears relatively parallel to the NW-SE trending Barisan orogen. This feature suggests that tectonic transport was likely at the NE-SW direction.
Characteristics of quaternary volcanic rocks based on petrographic analysis in Belandang Area, Ulu Ogan, Ogan Komering Ulu
Authors: Fazri Rahmad 
Published: November 2019

Abstract
Administratively the research area located in Belandang, Ogan Komering Ulu District, South Sumatra Province. The astronomical located at coordinates 04, 04’ 6.9 ″-04 07’ 54.2″ LS - 103 45’ 15.1 ″- 103 49’ 1.4″ BT. The research area included in the territory of the Bukit Barisan formed on the Late Oligocene-Early Miocene and controlled by Semangko Fault Northwest-Southeast oriented accompanied by an increase in the rate of volcanic activity. Then in the Plio-Pleistocene compression and removal process occurs that causes volcanism, so that at the end of the deposition of South Sumatra Basin filled by volcanic materials. The research area is dominated by volcanic deposits consisting of, Andesite Lava, Lapilli Tuff Unit, and Agglomerates. The method used is the petrographic analysis of the 9 rock samples were considered to represent the extent of the study area, consisting of 2 samples of Andesite, 1 sample of Lapilli Tuff, and 6 samples of Agglomerate. The results are show that volcanic rocks in the study area has undergone a change that is characterized by the presence of alteration minerals such as Carbonates, Chlorite, Sericite, Quartz and Clay minerals. The presence of alteration minerals indicate that the volcanic rocks in the study area belongs to the type of alteration Phyllic and Outer/Sub Propyllitic. Based on lithological characteristics, the research area enter into the Central and Proximal Facies.
An analysis of the optimalization of bucket series against soil removal rate at The Dredger 21 Singkep 1 in PT. Timah (persero) tbk, Bangka Sea Mining Unit of Bangka Belitung Province
Authors: Handayani Harminuke Eko 
Published: November 2019

Abstract
Dredger 21 Singkep 1 is a ship that serves to conduct excavation of tin ore offshore. The dredger is equipped with digging tools such as bucket, ladder, ladder roll, onder roll and other supporting tools that are connected to become one unit that is called bucket series. The bucket series is the main tool of the excavation process which continuously operates that has an impact on the depreciation of the performance capability of the equipment so that it is necessary to conduct an analysis of optimization of the bucket series in order to operate optimally and the targets of the work plan of the removal rate of the soil can be achieved. Based on the observation and data analysis on the field it is known that the applied ladder suppression is 0.46 meter at the top soil and 0.26 meter at tin-borne layer which results in 229.54 m3 / hour of soil removal rate which is very far from the target of the planned work of the soil removal rate determined by the production team of 389 m3 / hour, so to fulfill the work plan of the LPT the ideal ladder suppression that must be applied is 0.57 meter for top soil and at the tin ore is 0,31 meter, out of this ideal ladder suppression, is obtained the removal rate of the soil of 408.25 m3 / hour. In addition to that, the ideal length of the steek to achieve that removal rate of the soil should be at the average maximum length of 1225 mm.
Pseudo-static slope stability analysis around the landslide at railway tunnel, South Sumatera, Indonesia
Authors: Toha M Taufik , Setiabudidaya Dedi , Ghadafi Moamar A , Adiwarman Mirza , Irvan Muhammad 
Published: November 2019

Abstract
On January 23rd 2016 there was a landslide in the Lahat-Lubuk Linggau railway, right at the mouth of the railway tunnel in Lahat Regency. About 5 meters thick of soil covered the railway, causing the railway to be stopped for several days. Since the tunnel was built in 1928 until landslides occur in 2016 which means it has been 88 years. The landslide can be caused by several factors, these factors are slope geometry, physical and mechanical characteristics of rocks or soil, geological structure, hydrology and hydrogeology, and external forces such as ground vibration due to railway traffic and earthquake. The results of research on the main causes of landslides in the mouth of the railway tunnel include relatively steep morphological influences, degradation of rock strength due to weathering, dip rock structure in the direction of slope, and ground vibration due to earthquakes. Based on field observations, the slope next to the case study area of the landslide is also unstable. Therefore, it is necessary to analyze the slope stability in the area that has the potential to landslide, using a pseudo-static slope stability analysis on the consideration of the effect of ground vibration due to earthquakes is quite significant to slope stability. The results of the pseudo-static slope stability analysis is showing out that the factor of safety is around 1.22-1.16 with a seismic coefficient of 0.10-0.125 g. To anticipate future landslide we suggest to be conducted studies on slope stabilization methods including building retaining walls, drainage channels and shotcrete walls.
The trial of immobilization amphoteric metals cations in clay-cement hydroisolation barierrs
Authors: Stempkowska Agata 
Published: November 2019

Abstract
One of the main problem of degraded post-industrial areas, preventing their introduction into the secondary economic cycle, is pollution of soil and the impact of these pollution on groundwaters. With the new European Union directives, managers are encouraged to find sound solution for these problems. The process of interaction of contaminated areas is complicated, and the transport of pollutants from the danger place to the usable underground aquifers levels passes through a series of stages of varied mileages.The article presents the possibilities of using ground binders to reduce the emission of ions from soil. The tests have shown that in the case of amphoteric metals, it is possible to accumulate almost 100% of the contamination using clay-cement suspensions.
Evaluation of the impact of the CO/C reducer on the CO2formation in the process of pyrometallurgical recovery of Fe from converter slag
Authors: Kalisz D , Młynarczykowska A , Chyczyński A 
Published: November 2019

AbstractThe results of simulations of Fe recovery from steel slag containing iron oxides with C reducer dissolved in liquid slag and gaseous CO were presented in the paper. The simulations were performed with the use of a commercial program FactSage, and the calculations followed the procedure of dosing the reducer to slag in portions, each time reaching the state of thermodynamic equilibrium. The calculation procedure was realized sequentially, and the equilibrium composition of gaseous phase, nonmetallic phase and separated Fe was established at each calculation step. Gaseous products of CO and CO2reduction were removed from the system with each successive calculation step. The simulation revealed that reaching comparable results of reduction requires using a considerable amount of CO. Moreover, the CO2content in the gaseous phase and amount of separated Fe depend on the type of reducer. It was observed that the main mechanism was the reduction of iron with C. In this case the composition of gaseous products was mainly dominated by CO-CO2.
Improving the quality of hard coal products using the state-of-the-art KOMAG solutions in a pulsating jig nod
Authors: Kowol D , Matusiak P 
Published: November 2019

Abstract
Hard coal run-of-mine contains a significant amount of waste rock, which must be removed to improve the quality of the extracted raw material. Coal processing is an integral and extremely important part of the production of commercial assortments. Water pulsating jig is one of the basic devices in which the material is separated. The article presents some possibilities of improving the qualitative and quantitative parameters of the beneficiation products due to design changes and control of the jig beneficiation node.
Investigation of flotation of salts in their saturated solutions
Authors: Dubiel M , Ratajczak T 
Published: November 2019

Abstract
Flotation of NaCl, KCl and KPF6 in saturated aqueous solutions was investigated. The tests were carried out for salt particle sizes of >200, 100-200, 71-100 and <71μm. Flotation tests were performed in a Hallimond flotation cell. In addition, contact angle was estimated using a flotometric method and measured by the sessile drop technique. The angles were 5 degree for NaCl and KCl and 8 degrees for KPF6. Thus, there was mostly mechanical carryover of particles during the flotation test. However, an increase in the flotation yield of the tested salts with the increase of contact angle was observed.
Supercritical solvent extraction of lignite combustion products by water and HNO3 – Rare Earth Elements recovery study
Authors: Urbańczyk W , Lutyński M 
Published: November 2019

Abstract
Coal Combustion Products (CCPs) are anthropogenic materials generated during coal burning in coal-fired power plants and in case of lignite majority of these materials is disposed on land. CCPs contain various metals including Rare Earth Elements (REE). The purpose of this study was to assess if supercritical solvent extraction of CCPs, i.e. fly ash and bottom slag is effective to recover Rare Earth Elements. For that purpose two methods were compared: atmospheric and supercritical solvent extraction with the use of water and 10% HNO3. Result show that extraction of REE is unjustified when considering efficiency of solvent extraction process and obtained REE concentrations.
Innovative technological circuits for regular aggregates production
Authors: Gawenda Tomasz 
Published: November 2019

Abstract
The aim of the article is to discuss possibilities of production of aggregates with increased content of regular particles, on some well-known examples, as well as presentation of methods of aggregate production, which was not previously present in the industry. Traditional aggregate production circuits require application of three or four grinding stages (depending on the particle size of the feed), but for fine particle fractions of aggregates irregular grains occur on average approximate content of 10%. The innovative technological circuit can produce the aggregates with the content below 3% irregular grains, even in a single- or two-stage crushing circuit.
The comparison of laboratory and industrial copper ore upgrading indices during introduction of new flotation reagents
Authors: Pawlos W , Krzemińska M , Kurzydło P 
Published: November 2019

Abstract
This article draws attention to the need for the introduction of a laboratory testing methodology for new flotation reagents prior to the implementation of them for industrial use which would be more effective than the one currently used. Laboratory and industrial indicators of copper ore beneficiation during the testing of new flotation reagents are compared herein. For this purpose, two-stage laboratory tests and industrial trails were carried out on three types of collector mixtures, the results of which were used to analyse the technological indicators achieved. It has been concluded that the applied laboratory testing methodology requires a new approach that allows for a more precise correlation of variables which will allow the results of industrial trial to be predicted with greater probability than at present.
Electrostatic and magnetic separations for the recovery of metals from electronic waste
Authors: Suponik T , Franke D , Nuckowski P 
Published: November 2019

Abstract
The aim of the study was to recover metals from e-scrap using electrostatic and magnetic separation successively. The type of phases in the four magnetic separation products was determined by X-ray diffraction (XRD). Three grain classes were tested: 2.00 - 0.56, 0.56 - 0.32 and 0.32 - 0.10 mm. Based on the tests, it turned out that the separations were the most efficient for grain class in the range from 0.32 to 0.10 mm. The yields of the products obtained from electrostatic and magnetic separations were as follows: in the case of electrostatic separation, 13.12% metals and 86.88% plastics and glass; and for magnetic separation 1.51% of ferromagnetics, 1.56% of paramagnetics and 10.05 % of diamagnetics. In the diamagnetics Cu was dominant, while in the paramagnetics and ferromagnetics CuSn, γ-Fe and Ni, Fe3O4, respectively. Pb, Sn were identified in average amounts in all products of magnetic separation.
Investigation of the process of grinding of a char coal obtained from tires waste pyrolysis
Authors: Sidor J , Budzyń S , Czosnek C , Kozub –Budzyń G , Tora B 
Published: November 2019

Abstract
The paper contains results of examinations of grinding of char obtained from waste car tires. The grinding of the char was conducted in a laboratory vibratory mill of low vibration frequency. The examinations concerned the possibility of using a char as raw material in industry, particularly as a substitute for carbon black applied for the production of rubber. One of the basic parameters characterizing carbon black is particle size distribution as well as specific surface area. In the examinations, the char was obtained with following characteristic sizes of particles: d50 = 2.5 ÷ 9.3 µm, d90 = 13.3 ÷ 35.0 µm and specific surface area 74 ÷ 163 m2/g matching the particle size distribution and specific surface area characteristic of carbon black, which means that in order to grind a char, the vibratory mill can be used.
Komentarz [D1]: This terminology is not clear to use in the paper.
Investigation of mineral deportment in a copper ore from Botswana
Authors: Poloko N , Moatlhodi L K , Danha G 
Published: November 2019

Abstract
Understanding the characteristics of minerals is key in developing effective techniques for copper ore processing to maximise recovery hence income. Most studies have focused on understanding the fundamentals and principles of dissolution kinetics, oxidation and leaching of copper minerals. New developments and technologies have made it possible to reveal that copper ores are fascinating and complex minerals. Other research concentrates on chemical and mineralogical analysis, hence revealing information such as properties, compositional change and analysis. In this paper X-Ray Diffraction (XRD) and Quantitative Evaluation of Minerals Scanning Electron Microscopy (QEMSCAN) are used as tools in quantifying chemical and mineralogical attributes of a copper ore (chalcocite bearing mineral) from Botswana as the objective. Obtained information was not limited to grain size and distribution, mineral associations and liberations characteristics of economic minerals in the ore and quantitative information being the latter. XRF indicates that the copper ore contains phases such as Al203, CaO, MgO, TiO2, V2O5 and SiO2, which is the dominant mineral with 60.6 wt% as well as traces of elements Fe, S, Pb, and Co with wt% of <0.02. Scanning Electron Microscope (SEM) peaks also confirmed these elements to exist in the mineral. Quantitative X-Ray Diffraction (QXRD) analysis entailed phases present with silicates being the dominant phases and their existence on the mineral by wt%. SEM peaks showed evidence of Fe, Si, Cu, S etc. which is consistent with XRF data. In addition QESCAN also revealed grain size of cuprite particles to be greater than 45 μm with < 0.24 % liberated. The copper ore is characterized with a possibility of extracting metals or elements of economic value.
Mathematical model of dry coal deshaling by using FGX vibrating air table
Authors: Mijał W , Niedoba T , Polek D 
Published: November 2019

Abstract
Dry coal separation process is a relatively new method for coal separation in Poland. First air separators which were used on bigger scale was in United States before Second World War in 1930s. Nowadays is widely used in China, United States, Russia and all those places where access to water is limited. Last year’s very popular become separation by using vibrating air tables FGX where beneficiation process use air suspension which separate heavier particles from light coal grains. This separation process depends on different parameters like preparation of feed and it parameters, grain size fraction, air supply etc.. This paper will describe what is it a dry coal separation, modern separation techniques and in the main part focus on creating mathematical model which will present the quality of using this kind of process for coal deshaling. Mathematical model will base on dependence between calorific value and ash content in the tested samples.