فهرست مطالب

Iranica Journal of Energy & Environment
Volume:9 Issue: 3, Summer 2018

  • تاریخ انتشار: 1397/08/20
  • تعداد عناوین: 10
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  • Mahnaz Tayari , Esfand Burman Pages 153-162
    Auditing electrical energy in buildings is a feasibility study consisting of a comprehensive assessment of a building's electrical utilities in order to optimize energy consumption. In this paper a bottom-up method to estimate electrical loads is formulated that could help in disaggregating electricity use to specific end-uses in the absence of sub-meters in existing buildings. This method can be used for detailed benchmarking and identification of improvement opportunities. Implementation of the method in an office building, located in Tehran, shows that a satisfactorily match (94.66% for off-peak, 88.69% for mid-peak and 94.46% for on-peak) exists between the calculated loads with the data extracted from electricity bills. The building electrical energy auditing shows a maximum share of consumption for office equipment (32%) and a lower consumption for lighting (28%), space heating and cooling (17%), domestic hot water (12%) followed by catering and other electricity end-uses (11%). Through interpreting the energy auditing results, strategies for increasing energy efficiency has been suggested.
    Keywords: Electrical energy auditing, Off-Peak, Mid-Peak, On-Peak, Benchmarking
  • Foued Chabane , Elmoaiz Sekseff, Noureddine Moummi, Abdelhafid Brima Pages 163-167
    Our work an experimental study of a double-glazed solar air collector in the BISKRA site. The main objective of our work minimized thermal losses forward. The experimental model used is based on the addition of second glass and the increase in distance between the two panes. The study was carried out for the comparison between the average absorber temperature, glass and the outlet temperature and the efficiency for the single-pane and double-pane solar air collector with variable distance (1cm, 2cm and 3cm). Correspond to the three flow rates used. Experimental results show that the addition of second pane is effective in minimizing forward thermal losses for a solar air collector. The results obtained from the experimental readings show that the minimization of thermal losses forward is a very important factor for improving the performance of a solar collector. Experimental results show that the addition of second glazes is effective in minimizing forward thermal losses for a solar air collector.
    Keywords: double-glazed, solar air collector, efficiency, mass flow rate, thermal losses
  • Tara Chand Vadlamudi , Ravindra Kommineni, Bala Prasad Katuru, Niranjan Kumar I. N. Pages 168-175
    Gas turbines are always intended to give more specific work output for which continuous exposure to hot combustion gases is necessary. To increase the lifespan of the turbine blades active cooling should be applied to the High Pressure (HP) turbine blades. In the present work, a simple open cycle gas turbine is modeled to carry out thermodynamic analysis with different open loop steam cooling techniques: steam internal convection cooling (SICC), steam film cooling (SFC) and steam transpiration (STC) cooling. The effect of Turbine inlet temperature (TIT), Turbine blade temperature (T_b), and Compressor pressure ratio (CPR) on the coolant flow requirement and effect of T_b on the performance are estimated. The entire analysis is carried out with contemplation of variable specific heat (VSH) along with constant specific heats (CSH) for air and gas. Between VSH and CSH approaches, the former analysis leads to better performance from the first and second law efficiencies point of view. Irreversibility and Entropy generation rate are maximum in the combustor and they are less for VSH case in all cooling schemes and are decreased by 38.53%, 40.01%, and 40.40% for SICC, SFC and STC schemes respectively when compared with CSH(at TIT=1580 K, T_b=1123 K, CPR=19.1) analysis.
    Keywords: Gas turbine blade cooling, Internal convection cooling, Film, Transpiration cooling, Irreversibility, Entropy generation rate
  • Eustache Hakizimana, (Rwanda) Pages 176-181
    Electricity is most often generated at a power plant by electromechanical generators, driven by heat engines fueled by combustion. The combustion of peat for electricity generation is one among the energy contributors in Rwanda as Gishoma peat power plant that provides 15Mwh. The aim of this paper is to evaluate the life cycle environmental impacts of peat use for energy generation by focusing the dried peat for combustion at the power plant. Even though electricity is needed in Rwanda as one among the factors that boost the economy and development, the emission comes from peat has a high effect on the environment they considered impacts are global warming potential, acidification potential, and eutrophication potential. The Life cycle assessment shows that the level of emission gases emitted and at which level those gases are compared to the international standards Organization (ISO) then we found that carbon dioxide is the gas which is emitted with the high percentage of 80.30% followed by sulfur 11.23% nitrogen oxides of 4.62% and methane of 3.85%. All those emissions have the different impact on the environment as described by the ISO and International Panel on Climate Change(IPCC). According to the result found the quantity of gases emitted are approximate to the level of standard when we consider the other gases emitted in the other stage like extraction it can be too high it is necessary to carry the deep analysis of peat from site extraction to the end use of peat in energy generation process.
    Keywords: Life cycle assessment, Electricity generation, Environmental impacts
  • Mansoor Anbia , Zeinab Alsadat Khodashenas, Leila Kamel Pages 183-190
    The development of an efficient adsorbent for phosphate removal from wastewater to prevent the eutrophication of surface waters is very important. In this study, porous silicon powder prepared with acidic etching solution (HF: HNO3: H2O). Then, Zirconium-modified porous silicon has been synthesized by a simple and low-cost hydrothermal process. The morphology and structure of the samples were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD). This material has been used as an adsorbent for phosphate ion (PO43-) removal from synthetic aqueous solutions. The effect of operating conditions such as contact time, initial anion concentration, pH, the presence of competitive ions on the adsorption performances and the regeneration of the adsorbent have been investigated. Maximum adsorption amount of 47.7 mg P/g has been obtained at ambient temperature. The maximum removal of phosphate was reached at pH= 4 for Zirconium-modified porous silicon. The adsorption was almost unaffected by the presence of competitive ions. Regeneration tests have shown that the adsorbent retains its capacity after 3 adsorption-desorption cycles.
    Keywords: Chemical etching, Porous silicon, Zirconium, Eutrophication
  • Sheikh Shehab Uddin , Kazi Shoffiuddin Roni, Sheikh Nayeem Uddin, AHM Shatil, (Bangladesh) Pages 191-196
    This research paper analyses the current density and power density of a duel chamber microbial fuel cell using different substrate materials for different resistive loads. Sucrose, sugar and starch were treated as substrate and potassium ferricyanide was used as electron acceptor. The separation of the cathode and anode cell is provided by proton exchange membrane (PEM) in most of the microbial fuel cell (MFC). The most popular proton exchange membranes are nafion, hyflon, zirfon, ultrex CMI-7000 etc. But all of them are not available to use in this part of the world. As an alternate, salt bridge was used in this study as a PEM which is receptive to other ions & chemicals. Different organic materials like sucrose, glucose, starch can be used as substrate as those are available in organic wastage. As the container of bacteria, the sludge of drain of Dhaka was utilized. The voltage and current were measured across 9.81 kΩ and 5.91 kΩ resistors. 716.32 mV was measured as highest voltage across 9.81 kΩ resistor while 4.65 mA/m^2 and 3.09 mW/m^2 were recorded as maximum current density and power density respectively across 5.91 kΩ resistor for sucrose as substrate. The anode chamber was maintained in anaerobic condition. The temperature during these experiments was (22±2)º C.
    Keywords: Microbial fuel cell (MFC), Saltbridge, Current Density, Power Density
  • Rhoda M. Oranrejawu , O. Olatunji, Godwin Akpan, (Nigeria) Pages 197-203
    Hydro Electric Power (H.E.P.) is a critical infrastructure that powers industrial growth and economic development of any developing nation. However, variability in climatic condition is already having serious impacts on H.E.P. in Nigeria. The study examined the effect of climate variability on hydroelectric power generation in Shiroro Station Nigeria. Data used for this study were acquired mainly from secondary source. The climatic, Hydrological and power generation data used are already prepared document from 1990 to 2014 (25 years) period. The data were sourced directly from the production and Hydrological department of North South Power (N.S.P.). Relevant literature, journals and internet materials were also used for the study. Data collected were subsequently analyzed using inferential statistics such as trend analysis, reduction pattern analysis, spearman rank correlation and multiple regression analysis. Result revealed that there is variability in climatic elements and hydrological variables from year to year. Multiple linear regression analysis revealed that climatic/hydrological variables can only explained 75.40% variability in the amount of hydro power generated in Shiroro Station. The study calls for the development of pumped water systems so that the tail water can be reused particularly during periods of little or no rainfall and low inflow.
    Keywords: Key words: Climate Variability, Hydro Electric, Power, Generation, Hydrology
  • Yusup Setiawan Pages 204-209
    Paper mill producing several type papers has a wastewater treatment plant with an aerated lagoon system to remove their pollutants. But the removal efficiency of this system is still low so that the effluent is still not complying with the Indonesian of effluent quality standards yet. It needs pre-treatment plant before aerated lagoon. In an effort to improve the performance of wastewater treatment plant, study of wastewater characteristics, wastewater treatment, the establishment of treatment systems and equipment design have been carried out. After construction of pre-treatment plant, the field trial of waste water treatment plant using wastewater come from several type of paper produced has also been done. Result of laboratory-scale experiment shows that the paper mill needs a wastewater treatment with physical-chemical system before aerated lagoon treatment. Field trial of wastewater treatment shows that the removal of suspended solids (TSS) of 97%, COD of 88%, BOD5 of 85%, and a pH of 6.2 to 7.7 could be obtained by using 5 - 10 % NaOH solution at doses of 50-240 mg/L and 0.1% cationic polyelectrolyte (PE) solution as flocculants at dose of 1.0 to 1.5 mg/L. The addition of physical-chemical treatment plant can lighten the load on an aerated lagoon treatment. Effluent quality of aerated lagoon discharged into environment has met the Indonesian of effluent quality standard.
    Keywords: aerated lagoon, effluent quality standard, paper mill, physical-chemical treatment, wastewater
  • Jan Stenis , William Hogland Pages 210-215
    This paper presents an innovative method to enhance transportation of cargo applied on the ‘New Silk Road’. Allocation of shadow costs gives economic incentives to improve the Eurasian communications by employing the equality principle and the model for Efficient Use of Resources for Optimal Production Economy (EUROPE). The profitability increase, the technology is advanced, the environment and the living conditions improve. A single monetary key factor expresses aspects of interest and enables simultaneous monitoring, managing and evaluation. The method constitutes decision support tools for long-distance transportation at higher policy analysis organizational levels. The results of the case study point at usefulness for the launched methodology to reduce the spillages and losses when transporting cargo by truck along major transport routes. Peace and prosperity are promoted. The major benefits would be higher profits and less residuals.
    Keywords: Cargo Transportation, The EUROPE Model, New Silk Road, Transport Model
  • A.S.M. Riyad , Md. Rafizul Islam, Fatima Tuj Johora Pages 216-226
    The main focus of this study was to investigate the effect of fly ash content on the engineering properties of stabilized soils. To these attempts, two different types of fly ash, inorganic silt and Portland cement were collected. In the laboratory, the fly ash content of 10. 20 and 30%; inorganic silt of 10, 20 and 30% as well as cement content of 10 was used to stabilize soils. Result reveals that Atterberg limit decreases in relation to the increasing of fly ash content in stabilized soil at varying mixing proportions of fly ash content in soil. The different values of compressive strength of stabilized soils obtained from fly ash of different brand cement. In addition, the stabilized soil with cement content showed the highest value of compressive strength, whereas, stabilized soil with inorganic silt provides lowest value. The result reveals that the optimum content of fly ash was 20 and 30% for elephant and seven rings cement, respectively. The soil with organic content of 16% showed highest value of compressive strength, while, soil with organic content of 12.5% showed lowest value. Furthermore, the stabilized soils with fly ash showed comparatively the higher values of compressive strength than that of stabilized soils with inorganic silt content.
    Keywords: Soft soil, organic content, fly ash content, stabilization, unconfined compressive strength