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Le potentiel de solubilisation du prétraitement biologique des boues activées résiduaires (WAS) est limité en raison de sa structure en flocs. Les substances polymères supplémentaires (EPS) sont responsables de la formation de flocs. Dans cette enquête, une tentative a été faite pour perturber la structure des flocs de WAS en éliminant les EPS à travers le disperseur. Dans la première étape, le traitement du disperseur a libéré 242 mg/L d'EPS soluble à 3000 tr/min avec la durée des années 50 et provoque une défloculation de L'IS. Au cours de la deuxième étape, les boues défloculées ont été soumises à un prétraitement bactérien afin d'évaluer l'effet de la perturbation des flocs. Au cours du prétraitement bactérien, il a été constaté que les boues défloculées produisaient une solubilisation organique plus élevée de 23,9 % et une réduction des solides en suspension de 19,1 %, par rapport au témoin (10,2 %) et (8,7 %), respectivement. Un rendement en biogaz de 220 mL/g de DCO a été enregistré dans les boues défloculées et de 93 mL/g de DCO dans les boues floculées. De ce qui précède, il est évident que la défloculation a efficacement amélioré le prétraitement bactérien conduisant à plus de solubilisation et de production de biogaz. El potencial de solubilización del pretratamiento biológico para los lodos activados residuales (WAS) es limitado debido a su estructura de flóculos. Las sustancias extra poliméricas (eps) son responsables de la formación de flóculos. En esta investigación, se ha intentado perturbar la estructura del flóculo de WAS mediante la eliminación de eps a través del dispersador. En la primera etapa, el tratamiento dispersor liberó 242 mg/L de eps soluble a 3000 rpm con la duración de los 50s y provoca la desfloculación de WAS. En la segunda etapa, el lodo desfloculado se sometió a un pretratamiento bacteriano para evaluar el efecto de la interrupción del flóculo. Durante el pretratamiento bacteriano, se encontró que los lodos desfloculados produjeron una mayor solubilización orgánica del 23,9% y una reducción de sólidos en suspensión del 19,1%, en comparación con el control (10,2%) y (8,7%), respectivamente. Se registró un rendimiento de biogás de 220 ml/g de DQO en lodo desfloculado y 93 ml/g DE DQO en lodo floculado. De lo anterior, es evidente que la desfloculación mejoró efectivamente el pretratamiento bacteriano, lo que condujo a una mayor solubilización y producción de biogás. The solubilisation potential of biological pretreatment for waste activated sludge (WAS) is limited due to its floc structure. Extra polymeric substances (EPS) is responsible for floc formation. In this investigation, an attempt has been made to disturb floc structure of WAS by removing EPS through disperser. In first stage, disperser treatment released 242 mg/L of soluble EPS at 3000 rpm with the duration of the 50s and causes deflocculation of WAS. In second stage, deflocculated sludge was subjected to bacterial pretreatment to assess the effect of floc disruption. During bacterial pretreatment, it was found that deflocculated sludge produced higher organic solubilization of 23.9% and suspended solids reduction of 19.1%, when compared to control (10.2%) and (8.7%), respectively. A biogas yield of 220 mL/g COD was recorded in deflocculated sludge and 93 mL/g COD in flocculated sludge. From the above, it is evident that deflocculation effectively enhanced bacterial pretreatment leading to more solubilization and biogas production. إن إمكانات الذوبان للمعالجة المسبقة البيولوجية للحمأة المنشطة بالنفايات (WAS) محدودة بسبب هيكلها. المواد البوليمرية الإضافية (EPS) هي المسؤولة عن تكوين الندف. في هذا التحقيق، بُذلت محاولة لإزعاج هيكل التدفق عن طريق إزالة EPS من خلال الموزع. في المرحلة الأولى، أطلق العلاج بالمشتت 242 مجم/لتر من EPS القابل للذوبان عند 3000 دورة في الدقيقة مع مدة الخمسينيات ويسبب التلبد. في المرحلة الثانية، تعرضت الحمأة المفرغة للمعالجة البكتيرية المسبقة لتقييم تأثير اضطراب التدفق. أثناء المعالجة المسبقة للبكتيريا، وجد أن الحمأة المفرغة أنتجت ذوبانًا عضويًا أعلى بنسبة 23.9 ٪ وانخفاضًا في المواد الصلبة العالقة بنسبة 19.1 ٪، عند مقارنتها بالسيطرة (10.2 ٪) و (8.7 ٪)، على التوالي. تم تسجيل ناتج غاز حيوي قدره 220 مل/جم COD في الحمأة التي تم تفريغها و 93 مل/جم COD في الحمأة التي تم تلبدها. مما سبق، من الواضح أن إزالة التلبد عززت بشكل فعال المعالجة المسبقة للبكتيريا مما أدى إلى المزيد من الذوبان وإنتاج الغاز الحيوي.

Wireless Sensor Network (WSN) has an enormous scope of utilizations in detecting different parameters such as temperature, pressure, sound, pollution, etc. The sensed data in each sensor node are a valuable one. To communicate the information to the base station for further processing, a lot of strategies are available. Each sensor senses the data in different sampling rate depending upon the sudden raise in the sensing parameters. Data communication to the base station is very critical due to the dynamicity of the environment during the stipulated time.The sensed data should reach the base station before the data becomes invalid due to the violation of the deadline. In order to avoid deadline violation so that the sensed data becomes useless, this paper proposing a novel data collection algorithm based on the popular Earliest Deadline First (EDF) scheduling algorithm. The various simulation parameters are taken into account to verify the performance of the proposed method and the result shows that it achieves high throughput, low delay, high Packet Delivery Ratio (PDR) and low energy consumption.

Abstract A comprehensive review of cylindrical two-phase closed thermosyphon for low-temperature applications is presented in this paper. The review of literature based on the experimental studies of two-phase closed thermosyphon is categorized according to the utilization of refrigerants, nanofluids, external parameters, surface coating and modifications in the design of two-phase closed thermosyphon to provide a useful reference to the researchers in the field of cylindrical two-phase closed thermosyphon. The effect of geometrical parameters, power input, working fluid, inclination angle and fill ratio on the performance of thermosyphon has been studied thoroughly. The outcome of this review paper would help the research community to enhance the thermal efficiency of cylindrical two-phase closed thermosyphon. It would emphasize the need for utilization of environment-friendly refrigerants in two-phase closed thermosyphon, powered by a solar photovoltaic system, as these two would not affect the environment.

Abstract In recent years design of micro hydro power plants has been examined by various groups throughout the world due to its merits of offering better performance than the conventional fossil fuels to meet the energy need. Considering the portfolio of energy, the improvement of hydro power will partake in decrease of greenhouse gas emission and better malleability in the grid operation. This inquisition study examined the turbine of small hydro plant from the perspective of efficiency improvement while maintaining the global cost of the project per kW arrive within confined range. In this documentation an extensive epitomize of turbines available in India and other countries has been described. The selection of head, runner diameter along with its accomplishment are also presented. This study reveals an improvement for the design of turbines while comparing the functioning of other existing system for similar operating condition. Since most power plants now-a-day's use large turbines for the low power production, losses and overall cost increases, hence this survey will be helpful to reduce the cost of the plant. The reviews mainly focus on the study of existing turbines upto 100 kW. The importance of the turbine in micro hydro projects with respect to our current energy scenario is also highlighted.

Abstract Photovoltaic power plants pose challenges when integrated with power grid. The PV plants always focus on extracting maximum power from arrays. A new technique for tracking a pseudo-maximum power point for creating power reserve is presented. By using developed fractional open circuit voltage algorithm power is extracted from the array and continuously power is supplied to load as well as for charging the battery. In this project a 12V, 7Ah battery is used for charging and to avoid the revise current flow from the battery when input is, diode is replace by MOSFET which will stop the reverse current .Generally in other algorithm will trace the power when maximum input is coming for that time power circuit is disconnected from the load. In this case power developed algorithm is connected to designed moderate power five switch synchronous algorithm and operates in pseudo-operation which will continuously supply the power to charge the battery. This can be control by using PIC microcontroller which will generate the pulses and track the PV power. Precise measurement in the steady state shows that the converter finds the maximum power point with tracking 95.85%.

Economically viable production facilities for microalgae depend on the optimization of growth parameters with regard to nutrient requirements. Using microalgae to treat industrial effluents containing heavy metals presents an alternative to the current practice of using physical and chemical methods. Present work focuses on the statistical optimization of growth of Chlorococcum humicola to ascertain the maximum production of biomass. Plackett Burman design was carried out to screen the significant variables influencing biomass production. Further, Response Surface Methodology was employed to optimize the effect of inoculum, light intensity and pH on net biomass yield. Optimum conditions for maximum biomass yield were identified to be inoculum at 15%, light intensity to be 1500lx and pH 8.5. Theoretical and predicted values were in agreement and thus the model was found to be significant. Gas chromatography analyses of the FAME derivatives showed a high percentage of saturated fatty acids thereby confirming the biofuel properties of the oil derived from algal biomass.

Abstract Biodiesel is a renewable, nontoxic, eco-friendly and sustainable alternative fuel for compression ignition engines. In spite of having some application problems, biodiesel, in recent times, being considered as one of the most promising alternative fuels in internal combustion engine. It has been proven that the pollutants in the vehicular emissions have significant impacts on the ecological systems and on the health of human beings. Thus there is an increasing demand on tightening the emission standards of motor vehicles, as well as an ever increasing need for developing means of reducing emissions from in service motor vehicles. Biofuel, such as alcohol and biodiesel, could partly replace petroleum fuel, reduce toxic emissions and more importantly restrain the life-cycle emission of CO. In the present paper, earlier studies have been collected and analyzed. The aim of the present study is to evaluate the feasibility of biodiesel in automobiles, with special emphasis on emission aspects. Few aspects on durability and performance are also included. Evaluation is done on both conventional and CRDI engines, though literature on the latter are few and insufficient when compared to the former. Biodiesel use, when compared to diesel as a fuel, in conventional diesel engines with little or no modification leads to the substantial reduction in particulate matter (PM), hydro carbon (HC) and carbon monoxide (CO) emissions. This is accompanied by a light power loss, increase in fuel consumption and an increase in nitrogen oxide (NOx) emission.

Kerosene based hydrocarbon fuels are preferred candidates for the source of energy due to its stable properties. Based on the requirement of the combustor and the growing concern over pollutant, kerosene based fuels are modified. The fuel under investigation is a modified form of kerosene with ultra-low sulphur content. The effect of temperature on modified kerosene is studied for viscosity, surface tension, specific heat, density and ignition delay. The time delay for ignition of gas-phase mixtures of modified kerosene/oxygen have been measured using a shock tube facility. The experiments are conducted in the temperature range of 1200–1877 K, pressure range of 4–12 atm and equivalence ratio of Ø = 1.5, 1 and 0.5. The ignition delay time measurements were carried out using piezoelectric pressure transducers, which records the pressure rise due to ignition and simultaneously recording the light emission during the process of ignition using a photodiode. The ignition delay is represented as τign = 0.168841 × P−1.49 × Ø0.72 × e(14310/T)

Abstract The employments of Multilevel DC Link Inverters offer dependable points of interest attributable to the expansion in the highest levels at the yield output voltage and are broadly acknowledged for industrial applications. The execution of these bores on high when contrasted with the routine conventional two-level inverters because of their drawbacks. Be that as it may, the expanded number of devices, complex PWM control, and voltage-adjusting issue are a portion of the hindrances. This paper goes for presenting another topology, which can perilously decrease the switch number by introducing a module called polarity generation module. This topology gives a DC voltage fit as a fiddle of a staircase which approximates the corrected state of a directed sinusoidal wave to the extension inverter, which thusly interchanges the extremity to deliver an AC voltage with low THD and switching loss. The topology is tested by adopting a choice of control techniques and enhanced execution of the proposed inverter contrasted with the overarching topologies. The FPGA has been selected to verify the proposed inverter with modulating technique due its advanced futures and computing facility. For validation, simulation and experimental results are offered.