214 research outputs found
Salah satu upaya yang dilakukan untuk mengolah air yang mengandung senyawa Linear Alkyl BenzeneSulfonate (LAS) dan amonia adalah dengan proses ozonasi gelembung mikro dan filtrasi membran. Prosesini memanfaatkan keberadaan radikal hidroksida yang merupakan oksidator kuat yang mampu menguraikansenyawa organik dan anorganik bersifat racun dan sulit terurai di dalam air. Dari penelitian ini didapatkanbahwa proses ozonasi gelembung mikro dan filtrasi membran cukup efektif untuk menyisihkan senyawaLAS, namun tidak cukup efektif untuk menyisihkan senyawa amonia dalam air. Persentase penyisihan totalLAS untuk konsentrasi awal 30 mg/L, 50 mg/L dan 100 mg/L masing-masing diperoleh sebesar 89,82 %;84,20% dan 81,49% dan amonia sebesar 17,07%.</jats:p
Disinfection of Escherichia coli bacteria using hybrid method of ozonation and hydrodynamic cavitation with orifice plate
No full textEtude d'une huile biodégradable à base de Jatropha curcas comme matériau isolant pour transformateurs de puissance
No full textCe travail porte sur la caractérisation physico-chimique de l'huile de Jatropha Curcas et sa capacité à remplacer l'huile minérale dans les transformateurs de puissance. Ce produit présente plusieurs avantages sur les autres huiles végétales comme l'huile de palme ou l'huile de colza, qui recommandent sa production et son utilisation. En effet, la plante de Jatropha Curcas peut être cultivée sur des sols pauvres à faibles précipitations, évitant ainsi d'utiliser des sols plus fertiles pour sa culture permettant ainsi aux petits exploitants de réserver leurs terres aux cultures de base. Cette plante peut pousser facilement dans des zones où les niveaux de précipitations annuelles sont nettement inférieures à celles requises par d'autres espèces telles que le colza, le tournesol, le soja, le maïs, le palmier à huile et d'autres. Elle peut être cultivée sur tous les types de sol en Indonésie, même sur des terres arides, dans de nombreuses régions de l'Indonésie orientale, inexploitées en raison des difficultés à planter d'autres cultures. En outre, l'huile de Jatropha Curcas est un produit non alimentaire. En faisant subir à l’huile de Jatropha Curcas brute une estérification à base alcaline avec de l'hydroxyde de potassium (KOH), on obtient de l’huile de méthylester de Jatropha Curcas (JMEO) dont la viscosité et l’acidité sont acceptables pour les équipements à haute tension en particulier pour les transformateurs de puissance. Les propriétés physico-chimiques et électriques de JMEO ont été mesurées ainsi que celles de l'huile minérale (MO) pour la comparaison. Pour les propriétés physico-chimiques, il s’agit de la densité relative, la teneur en eau, la viscosité, l'acidité, l'indice d'iode, la corrosivité, le point d'éclair, le point d'écoulement, la couleur, l'examen visuel, et la teneur en ester méthylique. Quant aux propriétés électriques, elles concernent la rigidité diélectrique sous différentes formes de tension (alternative, continu et choc de foudre), les phénomènes de pré-claquage et de claquage sous choc de foudre, les décharges glissantes sur les surfaces de carton comprimé, immergé dans JMEO et MO. Les résultats obtenus montrent que les tensions de claquage moyennes en continu et en choc de foudre des huiles JMEO et MO sont très proches ; la tension de claquage moyenne de JMEO est même plus élevée que celle de l'huile minérale (de type naphténique). La mesure des tensions de claquage des mélanges d'huiles «80% JMEO + 20% MO» et «50% JMEO et 50% MO» montrent que la tension de claquage du mélange «80% JMEO + 20% MO» est toujours supérieure à celle de l'huile minérale sous tensions alternative et continue. Cela indique que le mélange d'huile minérale et de JMEO avec un rapport de 20:80 ne dégrade pas ses performances. Le mélange d'huiles peut se produire lors du remplacement de l'huile minérale par JMEO dans les transformateurs installés et en exploitation. L'analyse des caractéristiques des streamers (la forme, le temps d'arrêt, le courant associé et la charge électrique) se développant dans les huiles JMEO et MO sous tension impulsionnelle de foudre, montre une grande similitude. Aussi, la longueur finale (Lf) et la densité des branches des décharges surfaciques se propageant sur le carton comprimé immergé dans l'huile de Jatropha Curcas de méthylester (JMEO) et de l'huile minérale (MO), sous tensions de choc de foudre positif et négatif (1,2/50 μs), pour deux configurations d'électrodes divergentes (électrode pointe haute tension perpendiculaire et tangente au carton, respectivement), sont fortement influencées par l'épaisseur du carton comprimé. Pour une épaisseur donnée, Lf augmente avec la tension et décroît lorsque l'épaisseur augmente. Lf est plus long lorsque la pointe est positive que lorsque la pointe est négative. Pour une tension et une épaisseur du carton comprimé donnée, les valeurs de Lf dans l’huile minérale et l’huile JMEO sont très proches. [...]This work is aimed at the investigation of the physicochemical characterization of Jatropha Curcas seeds oil and its capacity to be an alternative option to replace mineral oil in power transformers. This product presents several advantages that recommend both its production and usage over those of other vegetable oils as crude palm oil and rapeseeds oil. Indeed, it may be grown on marginal or degraded soils avoiding thus the need to utilize those more fertile soils currently being used by smallholders to grow their staple crops; and it will readily grow in areas where annual rainfall levels are significantly lower than those required by other species such as palm oil, rape-seeds oil, sunflower oil, soybeans oil, corn oil and others. For instance, these plants can grow on all soil types in Indonesia, even on barren soil. The barren soil types can be found in many parts of eastern Indonesia that remain untapped because of the difficulty planted with other crops. Moreover, jatropha curcas oil is nonfood crops. Jatropha Curcas oil was processed by alkali base catalyzed esterification process using potassium hydroxide (KOH) to produce Jatropha Curcas methyl ester oil (JMEO) has a viscosity and a acidity that are acceptable for high voltage equipment especially in power transformer. The physicochemical and electrical properties of JMEO were measured as well as those of mineral oil (MO) for comparison. The physicochemical properties cover relative density, water content, viscosity, acidity, iodine number, corrosivity, flash point, pour point, color, visual examination, and methyl ester content. Meanwhile the electrical properties cover dielectric strength under AC, DC and lightning impulse voltages, pre-breakdown / streamers under lightning impulse voltage, creeping discharge over pressboard immersed in JMEO and MO. The obtained results show that the average DC and lightning impulse breakdown voltages of JMEO and MO are too close, even the average AC breakdown voltage of JMEO are higher than that of mineral oil (napthenic type). The measurement of breakdown voltages of two oil mixtures namely “80% JMEO + 20% MO” and “50% JMEO and 50% MO” shows that the breakdown voltage of the first mixture (i.e., “80%JMEO+20%MO”) is always higher than that of mineral oil under both AC and DC voltages. This indicates that mixing 20:80 mineral oil to JMEO ratio does not degrade its performance. The mixing of oils can occur when replacing mineral oil by JMEO in installed transformers. The analysis of the streamers characteristics (namely; shape, stopping length, associated current and electrical charge) developing in JMEO and MO under lightning impulse voltages, shows that these are too close (similar). It is also shown that the stopping (final) length Lf and the density of branches of creeping discharges propagating over pressboard immersed in Jatropha Curcas methyl ester oil (JMEO) and mineral oil (MO), under positive and negative lightning impulse voltages (1.2/50 μs), using two divergent electrode configurations (electrode point perpendicular and tangential to pressboard), are significantly influenced by the thickness of pressboard. For a given thickness, Lf increases with the voltage and decreases when the thickness increases. Lf is longer when the point is positive than with a negative point. For a given voltage and thickness of pressboard, the values of Lf in mineral oil and JMEO are very close. It appears from this work that JMEO could constitute a potential substitute for mineral oil for electrical insulation and especially in high voltage power transformers
The Plasma Electrolysis Phenomenon in a Two-Compartment Reactor for Chlor-Alkali Production
Get PDFChlor-alkali is one of the most important processes in the chemical industry. It produces chlorine and caustic soda, which become the main feedstock of daily products. The aim of this study is to report the phenomenon of plasma electrolysis and how it can be used in chlor-alkali production for more efficient energy consumption. When the plasma is formed, the current fluctuates and gradually declines. Plasma electrolysis begins with the process of electrolysis itself. Due to Joule heating, gas bubbles are formed and a sheath is made on both electrodes, resulting in the plasma field. Plasma electrolysis can be identified by its radical production. The higher the voltage and concentration, the greater the production of radicals. In 10 minutes or less, the number of OH radicals produced can reach 4 ppm at 400 V and 0.1 M. This amount is relatively small and is caused by other reactions consuming OH radicals to form other radicals such as chlorine. The energy consumption of plasma electrolysis in this study can reach 16 kJ/mmol Cl2 at 0.5 M NaCl solution
Ozone generation process using parallel plates plasma reactor at room temperature
No full textOzone is one of the most powerful oxidizing equipment, so it is effectively used to kill bacteria, viruses, and fungi. Many industrial processes use ozone because ozone can run without forming a by-product in water. Nevertheless, the utilization of ozone in Indonesia has not been applied maximally, due to the large cost of commercial ozonator equipment and operational life that is relatively short. In addition, many still do not comprehensively comprehend the ozonation process that is relatively very fast in the presence of ozone conditions that can only last a few minutes before parsing back into oxygen. In this study, the DBD (Dielectric Barrier Discharge) plasma reactor model with parallel plates for ozone generation at room temperature was developed. Furthermore, this study is more focused on conducting performance tests and optimizing ozone productivity in parallel spacer corona discharge chambers. This designated ozonator was treated as a plasma reactor to perform various tests with varying feed flow rates, input voltages, and gas feeds (compressed air and medical oxygen). After the productivity of the ozonators were tested with iodometric titration method, the ozonator’s productivity in generating ozone and its optimum operating condition were obtained. It can produce up to 0.82 g ozone/h with compressed air feed and 6.45 g ozone/h with medical oxygen feed
Hydrogen Production System Using Non-Thermal Plasma Electrolysis in Glycerol-KOH Solution
Get PDFHydrogen is one of chemical industry feedstock and automobile fuel, which is commonly produced by electrolysis. Electrolysis, however, has several constraints that are primarily due to its large energy requirement. Plasma electrolysis is a breakthrough method that not only improves hydrogen production but also suppresses energy consumption. This research has been conducted to investigate the effectiveness of plasma electrolysis on hydrogen product quantity and energy consumption by varying the voltage and glycerol concentration. The results of this research showed that an increase in voltage led to increased hydrogen production and energy consumption; the addition of glycerol caused a decrease in hydrogen production but still resulted in an increase in energy consumption. The process effectiveness of plasma electrolysis at 300V and 0.1M KOH was 8.1 times higher than Faraday electrolysis
Performance Test and Operating Condition Optimization of Parallel Plate Plasma Reactor for Carbon Dioxide Decomposition
Get PDFA dielectric barrier discharge (DBD) plasma reactor for carbon dioxide (CO2) decomposition was developed to address the current phenomena of CO2 emissions exceeding 400 ppm in the atmosphere. As is widely known, CO2 is one of the main causes of global warming and climate change. In this research, a parallel plate plasma reactor was designed by modifying the DBD reactor configured with two parallel electrodes. The casing of the reactor was modified using an acrylic plate that acts as a shell for the optimal contact between the CO2 gas and the electrodes. The DBD reactor uses a 220 VAC line power (PLN), 50-60 Hz frequency. The performance of the DBD reactor was tested and optimized by varying the regulator output (AC) voltage and the CO2 feed flow rate to obtain the optimal operating conditions from the parallel plate plasma reactor for decomposition of CO2. The optimal process performance for the 7-gram (ozone production equivalent) plasma reactor was achieved at a discharge power of 82 Watts and a feed flow rate of 1.2 L.min-1 with CO2 conversion of 4.413% and energy efficiency of 2.093×10-3 mol.J-1. The optimal process performance for the 10-gram (ozone production equivalent) plasma reactor was achieved at a discharge power of 74 Watta and a feed flow rate of 1.2 L.min-1 with CO2 conversion of 3.949% and energy efficiency of 2.074×10-3 mol.J-1
Effect of Low Flow Rate of Air Injection on Remazol Red Degradation in Contact Glow Discharge Electrolysis Reactor
Get PDFBackground and Objective: The plasma electrolysis requires a high amount of energy at the beginning of the process. The purpose of the study was to examine how air injection could reduce the energy of plasma formation. Furthermore, the effect of the flow rate of injected air on hydroxyl radical production and Remazol Red degradation were also studied. Materials and Methods: In this research, the air was injected directly through the glass sheath at the anode in Contact Glow Discharge Electrolysis reactor. Material used were Remazol Red RB-133 200 ppm as synthetic dye waste, Fe2+ 20 ppm as catalyst and Na2SO4 0.02 M as electrolyte solution. Result: For the same energy input, the higher the flow rate of air injection, the radical hydroxyl concentration increased to an optimum point at a certain flow rate. Moreover, the rate of airflow at optimum condition increased with increasing voltage. An airflow rate of 0.05 L/min and a voltage of 600 Volts was the optimum condition. The concentration of hydroxyl radical at this condition produced 19.0849 mmol/L after 30 minutes. Conclusion: This was an increase of 48.43% in comparison with the amount of •OH where air injection was not used. The presence of air injection also increased the degradation of Remazol Red. Within 5 minutes, Remazol Red degradation had reached 86.37% at an airflow rate of 0.05 L/min. This indicated a 53.59% increase compared to the degradation process without air injection
The Application of Catalytic Ozonation Technique using UV and Granular Activated Carbon (GAC) for Eliminating in Waste Phenol, COD, and 1,1,2,2-Tetrachloroethane
Get PDFProcess eliminating compounds of phenol, Chemical Oxygen Demand (COD), and 1,1,2,2-tetrachloroethane using catalytic ozonation technique with catalyst Granular Activated Carbon (GAC) combination with Ultra Violet (UV) light emission performed in this study. This study aimed to obtain the effectiveness of applications catalytic ozonation technique using system configuration Ozone/GAC and Ozone/UV/GAC to eliminate waste phenol 1,1,2,2-tetrachloroethane COD with circulation time (0, 15, 30, 45, 60, and 120 minutes). The wastewater was derived from the wastewater Laboratory of Polyester Industrial in Bogor. The results were analyzed, comprised of COD with Ferrous Ammonium Sulphate (FAS) method, phenol using aminoantipirin method, and 1,1,2,2-tetrachloroethane with Gas Chromatography-Flame Ionization Detector (GC-FID) method. The result of study shown that the configuration of the Ozone/ UV/GAC with an initial concentration of phenol 58,00 mg/L, COD 72,00 mg/L and 1,1,2,2-tetrachloroethane 32,96 mg/L resulted in the percentage of eliminating phenol 57,76%, COD 66,67% and 1,1,2,2-tetrachloroethane 98,74% while the configuration of Ozone/GAC with an initial concentration of phenol 55,00 mg/L, COD 72,00 mg/L and 1,1,2,2-tetrachloroethane 37,70 mg/L resulted in percentage of eliminating phenol 50,91%, COD 55,56% and 1,1,2,2-tetrachloroethane 100%ABSTRAKProses penyisihan senyawa fenol, Chemical Oxygen Demand (COD) dan 1,1,2,2-tetrakloroetana menggunakan teknik ozonasi katalitik dengan katalis Granular Activated Carbon (GAC) yang dikombinasikan dengan emisi sinar Ultra Violet (UV) dilakukan dalam penelitian ini. Tujuan dari penelitian ini untuk memperoleh efektivitas aplikasi teknik ozonasi katalitik menggunakan sistem konfigurasi, yaitu: Ozon/GAC dan Ozon/UV/GAC dalam penyisihan limbah fenol, COD dan 1,1,2,2-tetrakloroetana dengan waktu sirkulasi (0, 15, 30, 45, 60, dan 120 menit). Limbah cair yang digunakan berasal dari limbah cair Laboratorium Industri Polyester di daerah Bogor. Analisis yang dilakukan meliputi analisis COD dengan metode Ferro Ammonium Sulfat (FAS), analisis Fenol dengan menggunakan metode aminoantipirin dan analisis 1,1,2,2-tetrakloroetana dengan metode Gas Chromatography-Flame Ionization Detector (GC-FID). Setelah dilakukan penelitian, diketahui bahwa konfigurasi Ozon/UV/GAC dengan konsentrasi awal fenol 58,00 mg/L, COD 72,00 mg/L dan 1,1,2,2-tetrakloroetana 32,96 mg/L menghasilkan persentase penyisihan senyawa fenol 57,76%, COD 66,67% dan 1,1,2,2-tetrakloroetana 98,74% sedangkan konfigurasi Ozon/GAC dengan konsentrasi awal fenol 55,00 mg/L, COD 72,00 mg/L dan 1,1,2,2-tetrakloroetana 37,70 mg/L menghasilkan persentase penyisihan senyawa fenol 50,91%, COD 55,56% dan 1,1,2,2-tetrakloroetana 100%
Pre-breakdown phenomena in new vegetable oil - based jatropha curcas seeds as substitute of mineral oil in high voltage equipment
No full textInternational audienceDue to their high biodegradability, non-toxicity and higher fire safety guarantee, vegetable-based oils are considered today as a potential substitute for mineral and synthetic liquids for electrical insulation and especially in high voltage power transformers. However most of known vegetable oils are derived from food materials (rape-seeds, sunflower, soybeans, palms, corns and others). And one has to be vigilant to the fact that the replacement of mineral oil by natural ester fluids based on “renewably sourced” vegetable oils, does not create new problems as this could cause global food crisis due to diversion of food into insulating material oils or others (fuel). An interesting product can be jatropha curcas oil (JCO) extracted from the fruit seeds of jatropha curcas plants (“miracle tree”) which is non-food crops. These plants can be grown on marginal or degraded soils and thus enables to avoid the need to utilize those more fertile soils currently being used by smallholders to grow their staple crops; and they readily grow in areas where annual rainfall levels are significantly lower than those required by other species such as rape-seeds, sunflower, palm, soybeans, corns and others. This paper presents an experimental study of streamers phenomena in jatropha curcas methyl ester oil (JMEO) and mineral oil (MO) under positive and negative lightning impulse voltages (1.2/50 μs); JMEO is obtained by alkali base catalyzed trans-esterification process of JCO to reduce the viscosity and acidity. It is shown that basing on the streamer characteristics (shape, stopping length, velocity, current and electrical charge), JMEO could constitute a potential substitute for mineral for electrical insulation and especially in high voltage power transformers
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