bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pinch Analysis For Styrene Production With Lummus/UOP Smart SM Technology
Authors: Buchori Luqman , Putri Farah Marda Yesica 
Published: February 2021

Abstract
Styrene is an organic compound used for the synthesis of polymers, co-polymers, and rubber. Generally, the reaction to form styrene comes from the dehydrogenation of ethylbenzene. This reaction occurs when the compound is in the vapor phase and is endothermic. One of the technologies for ethylbenzene dehydrogenation is Lummus/UOP Smart SM. This technology uses oxygen to heat the reaction and makes the hydrogen disappear, so the reacting reaches the highest ethylbenzene conversion. The focus of this research was pinch analysis on Lummus/UOP Smart SM. The first step in pinch analysis is data extraction. An alternative is to perform pinch analysis with a composite curve, problem table, shifted composite curve, and grand composite curve. Then is continued to create a design Heat Exchanger Network (HEN). The application of pinch analysis to evaluate heating duty, cooling duty, Maximum Energy Recovery (MER), and determine the exact HEN for optimal energy. In this research, the integration of the process showed not optimal results, especially in cooling duty, because the energy recovery was obtained small, and for heating duty saved about 14%.
Simulation of Scale-up Criteria for Side-entry Stirred Tank in Laboratory Scale
Authors: Fathonah N N , Madhania S , Nurtono T , Winardi S 
Published: February 2021

Abstract
The hydrodynamics in side-entry stirred tanks with similar geometry ratio were studied using Computational Fluid Dynamics (CFD) simulation methods. Scale up is done using a flat bottomed cylindrical side-entry stirred tank with diameter D=0.4 m (T40) and D=0.6 m (T60) in a laboratory scale. The type of stirrer is a commercial three-blade marine propeller with a ratio propeller to tank diameter d/D = 0.1. The effect of the constant propeller rotational speed (N) and constant tip speed (utip
) is evaluated on the pumping capacity and fluid velocity profile in the discharge stream area as well as the flow pattern in the whole tank. Flow patterns are a form of fluid behavior that is easily changed when there are operating conditions in the tank varying, for example when the propeller speed is changed. Considered from the effectiveness of mixing performance, the scale-up criteria similar geometry to the constant N is more beneficial. Visually shows that in the same time span the flow pattern on the T60 is more able to reach the entire tank area. The stagnant area is not visible, whereas in T40 there is still a stagnant flow area in the upper left corner of the tank. However, constant N cannot be used as a reference for scale-up of side-entry stirred tank into a larger scale. Because the phenomenon changes quite dramatically which is caused by a change in propeller diameter. Meanwhile constant utip
gives results that are closer to T40 and T60 in the flow pattern and the distribution of velocity in the discharge stream. So for side-entry stirred tank that has a similar geometry, scale-up criteria with constant utip
is more appropriate to be applied.
Preliminary Study of Slow Pyrolysis for Banana Peel Biomass in Tube Chamber based on Computational Fluid Dynamics
Authors: Triwibowo B , Rengga W D P 
Published: February 2021

Abstract
Dry banana peel as a biomass can be converted towards bio-char using slow pyrolysis methods. The tube chamber that used where slow pyrolysis occur must be in relatively uniform temperature at to ensure the condition are fulfilled in the process. Computational Fluid Dynamics (CFD) method applied to estimate the temperature distribution inside the tube chamber and time needed for the uniformity of temperature is achieved. The tube chamber dimension is 36.5 cm of height with 7.7 cm diameters. The grid generation process performed for the chamber using full hexahedral cell with average orthogonal quality close to 1 that indicated excellent mesh. The observation plane placed right in the middle of tube chamber axially where 6 observation points was placed to observe the change of temperature over time. The simulation process take place in transient regime where the temperature change overtime. The heating sources with heat flux entering uniform in whole outer surface as the wall temperature will peak at 923 K. The heat balance and P1 radiation method was used to obtain the temperature distribution. The simulation results showed a good agreement compared to the experiments. The distribution temperature showed that minimum temperature for pyrolysis process (650°C) already achieved in all of the region. The uniformity of temperature itself achieved after the surfaces of tube chamber reached 650°C for more than 200 seconds.
Purification Process of Poly Methyl Methacrylate Products Made with Suspension Polymerization Techniques
Authors: Ariyanto Maria Angelina , Zulfa Ifada , Hernugrahanto Kukuh Dwiputra , Ferdiansyah  , Trisanti Prida Novarita , Sumarno  
Published: February 2021

Abstract
Poly Methyl Methacrylate (PMMA) is a commodity polymer produced from Methyl Methacrylate (MMA) monomer. This applied in various industries such as automotive and in the manufacture of artificial bones. Suspension polymerization techniques are able to produce polymer powders in micron size, uniform molecular weight and desired particle size distribution. This research was initiated by conducting polymerization process by heating Polyvinyl Alcohol (PVA, dispersant)/aqua dest (H2O) mixture accompanied by nitrogen gas purging and stirring, then MMA and Benzoyl Peroxide (BPO, initiator) was added. The results of the polymerization process produce PMMA products in the form of powders which are suspected to still contain MMA, BPO, and PVA so that the washing process is required for PMMA products. Therefore, PMMA products resulting from the polymerization process are washed with water solvent with stirring, then the results of washing PMMA products are filtered and dried. The results of final PMMA products in the form of white powder which are then analyzed using Fourier Transform Infrared Spectroscopy (FTIR) analysis showed that product there is still a residual MMA. Scanning Electron Microscopy (SEM) analysis which results produce spheres of varying size and average particle size of 64.45 µm. Particle Size Analyzer result presents the average size of 62.05 µm.
Bioethanol Purification from Fermentation of Suweg Starch Using Two Stage Distillation Method
Authors: Hargono H , Jos B , Purwanto P , Sumardiono S , Zakaria MF 
Published: February 2021

Abstract
This study aims to employ two-stage distillation in the purification of fermented ethanol. Furthermore, 200g/L Suweg starch was fermented by Simultaneous Saccharification and Fermentation (SSF) method using StargenTM 002 and Saccharomyces cerevisiae at a concentration of 1.5% (w/w) and 1.10% (w/w), respectively. Therefore, 99.52 g/L or 13.82% bioethanol was produced and further purified through a distillation method. Subsequently, the first stage was performed in a column without filling material, while the second was in a column with glass ball-shaped material (marbles). This two phase exposure was conducted to expand the contact between the bioethanol-water vapor mixture and the suffing material. In addition, the temperature was set at 78ºC, while the duration was varied at 45, 60, 75, and 90 minutes. Therefore, the samples were analyzed using high-performance liquid chromatography (HPLC) and the maximum yield of 94.6% was produced at 75 minutes.
Influence of microwave power and temperature on the silica leaching process
Authors: Hidayati N , Jelita R , Jefriadi  , Wicakso D R , Fitrila N A , Rachmadiyani W A , Asshifa  , Rosanti W , Mirwan A 
Published: February 2021

Abstract
This research presents a study for the silica leaching from peat clay in alkalic sodium hydroxide under microwave-heated condition. Microwave bases leaching was implemented using the Iwaki Pyrex glass reactor in a modified microwave oven. The characterization of peat clay was specified by X-ray diffraction (XRD) analysis and X-ray Fluorescence (XRF) analysis. An investigation was made of the influence of microwave power, temperature, and reaction time on the silica leaching recovery. An enhancement on the silica recovery for 12 M sodium hydroxide, solid/liquid ratio 0.03 g/mL, and 15 min reaction time was obtained 30.62 %-wt and 27.85%-wt for 900 W and 90 °C respectively. The microwave assisted leaching is more efficient regarding overall silica dissolution.
Study on Ultrafiltration of Hospital Wastewater Treatment Effluent
Authors: Mahirullah M , Widiasa I N 
Published: February 2021

Abstract
The Ultrafiltration (UF) membrane is beneficial in the wastewater treatment plant (WWTP), including the hospital WWTP. The formation of fouling deposits is often encountered on the membrane surface. Pretreatment and cleaning strategy are needed to maximize flux recovery for the fouled membrane. Therefore, the investigation were conducted for the membrane UF in terms of performance and the cleaning of the UF membrane in terms of cleaning efficiency. Pretreatment of sedimentation and cloth media filtration (CMF) is recommended because the flux reduction rate of 3.3% - 8.2%. The cleaning procedure with NaOCl was carried out under various concentrations with pH 12.6. The cleaning duration was determined as 4 h. The best result of membrane cleaning for the experiment with pretreatment required 100 ppm NaOCl to achieve 96.43% flux recovery, 77.77% fouling removal and hydraulic cleanliness criterion 0.037. Meanwhile, the experiment without pretreatment required 500 ppm NaOCl to achieve 80.59% flux recovery, 51.85% fouling removal and hydraulic cleanliness criterion 0.24.
Selection and Cultivation of Microalgae for CO2 Biofixation
Authors: Widayat  , Suzery M , Satriadi H , Wahyudi  , Philia J 
Published: February 2021

Abstract
Climate change has become the main focus of the world which caused various negative impacts throughout the earth. Carbon dioxide is one of the greenhouse gases that effect on climate change and environmental pollution. One of the promising opportunities to reduce CO2 emissions in the atmosphere is bio fixation by microalgae. Many species of microalgae have the ability to capture carbon dioxide as its carbon source for the photosynthetic process. This research aimed to cultivate many species of microalgae in the carbon dioxide incubator and study its CO2 bio-fixation capability. Microscopic analysis was occurred to identify microalgae morphology. The optical density measured representing growth rate of microalgae. Tetraselmis sp. and Navicula sp. are suitable for CO2 biofixaton due to the good adaptation to the existence of CO2 in the medium.
Thermodynamics and Kinetics Study of Diethyl Carbonate (DEC) Synthesis from CO2, Ethanol, and Epoxides with Various Catalysts
Authors: Wiguno A , Tetrisyanda R , Anggerta L A , Liemen K D R , Rahma S W , Wibawa G 
Published: February 2021

Abstract
Carbon dioxide (CO2) has been the main contributor for global warming over the past decades. However, it can potentially be utilized as raw material of valuable products, such as organic carbonate compound namely diethyl carbonate (DEC). Formation of DEC via indirect route from CO2 and ethanol is accompanied with epoxides as dehydrating agent. This work has been devoted to study thermodynamics and kinetics of indirect DEC synthesis using ethylene oxide (EO), propylene oxide (PO), and butylene oxide (BO) with various catalysts. Data from scientific journals and previous experiments conducted at Laboratory of Thermodynamics, ITS were analyzed in this study. Based on the value of (ΔG), it was found that indirect synthesis using EO is the most spontaneous reaction, followed by BO and PO, respectively. Simulation using Aspen HYSYS V8.8 also reveals that reactant and product system after 3 hours of reactions falls into vapor-liquid region and superheated region. Meanwhile, kinetics evaluation of experiment using PO and KI/EtONa catalyst showed that the aforementioned reactions are exothermic due to decreasing value of reaction constant upon reaching certain temperature. Based on Arrhenius equation while presuming that the reaction is elementary and non-elementary, activation energy was estimated as 55.62 kJ/mol and 54.80 kJ/mol, respectively. Furthermore, the use of KI/EtONa as catalyst resulted the highest yield among other catalysts namely KI, KI/CeO2, and KI/Zeolite.
Improving the performance of crushed limestone concrete utilizing supplementary cementitious materials: A case study in Iraq
Authors: Muhsin Adnan A. , Al-Saati Nabeel Hameed , Heil Suad Mohammed , Hashim Khalid , AlKhayyat Ahmed H. 
Published: February 2021

Abstract
This paper presents an experimental work conducted to study the properties of concrete incorporating (0-100) % of local (in Iraq) crushed limestone (CLS) as a partial replacement of coarse aggregate. Supplementary Cementitious Materials (SCM) such as High Reactivity Metacaoline (HRM) and Rice Husk Ash (RHA) were added to the mixtures to improve the properties of fresh and hardened concrete. The selective mixtures in this study were arranged into three groups, the first without (SCM), the second with (RHA), and the third with (HRM). Each of them (being with different ratios of (CLS) as a coarse aggregate) was tested for comparison with the reference mixtures. The slump and air contents were evaluated for the fresh concrete. The absorption as well as compressive strength (CS) and flexural strength (FS) were evaluated for the hardened specimens after 7 and 28 days. According to the results, the concrete with CLS as a coarse aggregate gained less performance than the ordinary concrete but the (SCM) improved the properties of the concrete mixtures. The results show that the HRM was more effective than the RHA with respect to the mechanical properties.
Mitigation of wastewater biological pollution using the electrocoagulation method
Authors: Dosh Zinah K. K. , Maslookhi Ammar K. A. , Al-Saidi Alyaa N. , Alenezi Basel , Amoako-Attah Joseph 
Published: February 2021

Abstract
Biological pollution of water and wastewater is a global grave concern, especially in developing countries due to insufficient treatment and sanitation. Additionally, the poor economy of the majority of the developing countries limits both applications of advanced treatment technologies and modern monitoring systems, which intensifies the problem of biological pollution. In this investigation, the electrocoagulation method, which is in situ production of coagulation agents by passing electric current via metallic electrodes, has been used as an affordable treatment method for the removal of bacteria from municipal wastewater (E. coli as an indicator). Wastewater sample was collected from Al-Rustamyiah wastewater treatment plant, Baghdad city, Iraq. In this investigation, the electrocoagulation unit was supplied with iron electrodes (Fe-ELE). The impacts of current density (CD) and electrodes gapping (EG) on the performance of the Fe-ELE performance were optimized to attain the best activation percentage. The obtained results showed that the Fe-ELE achieved full deactivation of the E. coli after 45 minutes of treatment at EG of 5 mm, CD of 2 mA/cm2, and an initial pH of 6.0.
Using SF and CKD as cement replacement materials for producing cement mortar
Authors: Abdulredha M , Muhsin Adnan A. , Al-Janabi Abduljaleel , Alajmi Bader N. , Gkantou M. , Amoako-Attah Joseph , Al-Jumeily Dhiya , Mustafina Jamila , AlKhayyat Ahmed 
Published: February 2021

Abstract
When considering binding materials, cement mortar is thought to be one of the most conventional and effective materials. The cement mortar is mainly containing cement, sand (fine and rough), and water. In fact, there are many environmental and economical limitations to the usage of raw materials in mortar blends. For considering these limitations, many researchers studied the ability to incorporate waste-materials to fully or partially replace conventional raw materials. In this research, compressive strength and ultrasonic pulse velocity (UPV) will be studied by incorporating (SF) and (CKD) of mortar specimens and study the effect after 7,14, and 28 days. The obtained results from the collected samples (M1, M2, and M3) were compared with the reference mortar samples that contain ordinary Portland cement (OPC) only. The collected results showed that samples with CKD and SF have less compressive strength than ones with OPC with 28 days of curing. In addition, with higher CKD content, lower compressive strength was obtained. Samples (M1, M2) have the highest (UPV) values at different curing periods.
Numerical study of concrete-filled aluminium alloy tubular columns under eccentric compression
Authors: Ali Shafayat Bin , Kamaris George S. , Gkantou Michaela , Kansara Kunal , Hashim Khalid 
Published: February 2021

Abstract
Concrete-filled aluminium tubular (CFAT) columns have numerous benefits, such as aesthetic appearance, less self-weight and good corrosion resistance, over conventional concrete-filled tubular columns. A limited body of research exists for CFAT columns, and the research on the behaviour of CFAT columns under eccentric loading is rather rare. Therefore, the present study aims at investigating the eccentric compressive response of CFAT columns by means of numerical analysis. The numerical models were developed considering nonlinear behaviour of the materials. The models were validated against experimental data obtained from concentric compression tests of CFAT columns. The columns used in the experiments were 6082-T6 heat-treated aluminium alloy square tubes filled with 30 MPa cube strength concrete. The validated models were used to study the influence of different loading eccentricities on the behaviour of CFAT columns. The results are discussed in terms of ultimate strengths and load-lateral displacement responses. A comparison is drawn between the column capacities obtained from the numerical analysis and calculated by European standards. It is found that the design formulae provided in Eurocode are conservative for the eccentrically loaded CFAT columns.
Aluminium alloy cross-sections under uniaxial bending and compression: A numerical study
Authors: Georgantzia Evangelia , Gkantou Michaela , Kamaris George S. , Kansara Kunal , Hashim Khalid 
Published: February 2021

Abstract
The current study numerically investigates the structural behaviour of aluminium alloy square and rectangular hollow cross-sections under compression and uniaxial bending. Material and geometric nonlinear responses were carefully considered within finite element modelling. Geometric imperfections were also included through the execution of an initial eigenvalue buckling analysis. A thorough parametric study was carried out over a range of width-to-thickness ratios used in practice. Different initial loading eccentricities were examined generating various ratios of compressive axial load and bending moment at failure. The relatively new 6082-T6 heat-treated aluminium alloy, which is increasingly employed in structural applications owing to its high strength, was selected for this study. Based on the obtained numerical capacities, the EN 1999-1-1 design interaction curves were assessed providing rather conservative predictions, particularly for the stockiest cross-sections. The simplified Continuous Strength Method was, also, evaluated exhibiting slightly more accurate with less scattering strength provisions.
Determining the Ultrasonic Pulse Velocity (UPV) of Cement Mortar with Partial Replacement of OPC with CKD and SF
Authors: Hashim Raad , Al-Ameeri Abbas , Diwan Alaa Ali , Alajmi Saad , Yeboah David , Al-Jumeily Dhiya , Mustafina Jamila , AlKhayyat Ahmed 
Published: February 2021

Abstract
A significant number of researches pointed to the serious environmental and health effects of the Ordinary Portland Cement (OPC), including the harmful emissions and alkaline wastewaters. Therefore, the development of eco-friendly alternatives for the OPC is one of the priorities of nowadays studies. However, the suggested eco-friendly alternatives to the OPC might possess negative influences on the properties of the concrete. This research aims at investigating the applicability of by-product materials, such as cement kiln dust (CKD) and silica fume (SF), as an alternative to OPC in the cement mortars. The mortar specimens were mixed with 0 to70% CKD with SF (equal values) as a partial replacement for cement. The hardening samples have been tested by the UPV test at ages 1 week to 4 weeks. The results indicated that high ratios of CKD and SF replacements result in a slight decrease in the pulse velocity of specimens, while small replacement ratios show improvement in these properties. Time of curing is very important in improving the properties of the hardening mortars. Using a small amount of CKD and SF (20-30%) could improve the durability of cement mortars and it seems to be reasonable value in mixers.
Statistical analysis of groundwater quality parameters in selected sites at Kirkuk governorate/Iraq
Authors: Ibrahim Ahmed Khaleel , Ahmed Salwa Hadi , Radeef Ahmed Yasir , Hazzaa Massod Muhsin 
Published: February 2021

AbstractThis study aims to clarify the distribution of groundwater qualitative characteristics in Daqouq district within Kirkuk governorate, the study included 14 wells that were selected in the area located in the southern part of Kirkuk province, and which included different activities such as agricultural, industrial and residential to the north in the Daqouq district. Water samples were collected from the wells once every two months from December 2016 to April 2017. The physical tests were performed such as electrical conductivity, total dissolved solids and chemical tests that included pH, cations such as calcium and magnesium, anions such as sulphates, nitrates and chlorides and concentrations of trace elements such as lead, cadmium and zinc were measured using standard methods. The three- dimension contour maps were drawn to illustrate the distribution of the above properties in the study area. The wells showed that the highest rate of electrical conductivity was 1600μs/cmin W4 and the highest concentration of calcium in W5 was 260 mg/L and the highest rate of lead was 2.2μg/Lin W13, and they showed that the difference in the quality of water was according to land use, agricultural, residential or industrial, in the properties of electrical conductivity, total dissolved solids, nitrates, chlorides, and trace elements.
Concrete Erosion Modelling by Water Jet using Discrete Phase Method
Authors: Ismaeil Rawaa H. , Hilo Ali N. , Al-Gasham Thaar S. , Abd Ali Hameed 
Published: February 2021

Abstract
To a great extent, for hydraulic structures,the durabilityrelies upon the resistance that the concrete surface offers to mechanical wear. The surface damage caused by the process of uninterrupted material removal,induced by the impact of the water-borne solid particles, is termed hydro-abrasion. In nearly all hydraulic structures, this kind of progressive deterioration of the concrete surfaces is observed, in different intensities. Obviously, such hydro-abrasive concrete wearing normally results in areduction in the service life of the hydro-technical facility, and consequently because of the repairs required, thenon-functioning of the facility during the repair period results in an expenditurespike. The influence exerted by the flow inclination angle was determined in this study. Numerical estimations were made of the four different angles (30°, 45°, 60°and 90°) employing the ANSYS software and discret phase model (DPM) to simulate the fluid particles. From the findings of numerical investigations, it was clear that the maximum erosion rate can be reached when the flow inclination angle is 45° while the lowest rate can be achieved at a flow inclinationangle of 30°.