فهرست مطالب

Energy & Environment - Volume:7 Issue: 2, Spring 2016

Iranica Journal of Energy & Environment
Volume:7 Issue: 2, Spring 2016

  • (Special Issue)
  • تاریخ انتشار: 1395/02/10
  • تعداد عناوین: 17
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  • Y. Hng, Y. Yusup (Malaysia) Pages 84-93
    Turbulence intensity measurements of vertical axis wind turbine (VAWT) are essential to detemineitsefficiency and performance. In this study, the eddy covariance (EC) method was used to characterise the flow and directly measure turbulence of a VAWT in a controlled indoor laboratory using an ultrasonic anemometer (at 10 Hz) at specific grid positions of upwind and downwind (in the wake) of the VAWT. In constrast to numerical simulations, this method has the potential to accurately quantify turbulence of wind turbines and thus able to describe the flow patterns around a VAWTexperimentally. Results show that at the upwind position, some of the swept area of the VAWT obstructed the flow due to the counter current flow generated by the VAWT rotors’ rotation while causing some flows to be diverted and concentrated to the concurrent flow area of the VAWT. In the wake of the VAWT, flow velocities and turbulence decreased and dispersed while at the centre line, vertical turbulence decreased towards the bottom (ground) swept area.This downward transfer of turbulence caused generally negative vertical momentum transfer. However, a slight increase of turbulence was observed at the ground surface due to flow deflection.
    Keywords: EC method, Turbulence, Vertical Axis Wind Turbine
  • S. Jijai, G. Srisuwan, S. O., Thong, I. Norli, C. Siripatana (Thailand) Pages 94-102
    This study aimed to evaluate the Biochemical Methane Potential (BMP) of different types of wastewaters and sizes of granules. The granules (CS: from a cassava, SS: a seafood, and PS: a palm oil factory) and wastewaters initial Chemical Oxygen Demand (COD) were 18,800, 4,200 and 100,000 mg/l respectively). Modified Gompertz equation was used to compare the data from the experiments. Wastewater from a cassava factory gave the highest BMP when used with only granules from its own source (CS). Wastewater from seafood factory had the highest nitrogen content thus, represented the most imbalance nutrient source. In this case, mixgranules (SS) gave highest BMP. Palm oil mill effluent did not match COD: N ratio criterion and had too high COD level which caused substrate inhibition. Here the mix-granules (PS) gave highest BMP. In general, the larger granule size and the nutrient balance could improve the efficiency and hence increase the biogas production rate. The initial COD or different substrate has a strong effect on BMP and the maximum specific methane rates whereas the different sizes of granule have an effect on the length of lag phase period. In most cases, it was sufficient to represent the experimental data with traditional modified Gompertz equation and Monod models.
    Keywords: Biogas production, Anaerobic digestion, Modified Gompertz, Agro, industry
  • M. A. Ubaidah, S. M. H. Syed Hilmi, M. F. Mohammed Yunus, S. Tahiruddin (Malaysia) Pages 102-109
    Freely emitted biogas at palm oil mills has been regarded as untapped energy source nowadays, despite being recognised as major contributor to the global warming. Up till now, most of palm oil mills are still operating with the conventional anaerobic digestion systems which may not spur biogas industry to life. This study shall explore biogas production between day and night under existing mill operating conditions at KKS Bukit Benut Effluent Treatment Plant (ETP). Biogas produced during day time was 62% as compared to 38% during night time with the total methane emission of 490.3 kg/day. The methane concentration recorded at the digester tank ranged from 58.7 to 68.5%. The correlations between various factors that may influence biogas production were investigated. The finding shows that substrate feeding is the most influencial factor leading to high biogas production during day time.
    Keywords: Anaerobic digester, Baseline study, Biogas production, Methane production
  • M.N. Noorzalila, M. A. Nurul Asikin (Malaysia) Pages 109-114
    The increasing number of environmental pollution through carbon emission from combustion of fuels and the unstable fluctuation of global petroleum prices have alarmed a signal that a clean alternative energy is in urgent need. Through the past years, a lot of researches have been focusing in producing biodiesel which can be made from natural elements such as plants and recyclable materials, hence defined its renewable properties as biodegradable, sustainable and non-toxic fuel. The focuses have been varied from the variable of feedstock used, development of catalysts and different kind of methodologies for the production of biodiesel. In this study, the feasibility of biodiesel to be synthesized from a low cost feedstock which is coconut waste has been investigated. The abundance of coconut waste readily obtained from the market, restaurants and hotels were converted to a value-added fuel through an in-situ transesterification. It is found that at ratio of 12.5:1 of methanol to solid coconut waste, with reaction time of 6 hours and 5wt% of catalyst could obtain up to 90% of biodiesel content. This investigation concludes that coconut waste has the potential to be further used for synthesis of biodiesel through in-situ transesterification reaction.
    Keywords: Low, cost feedstock, Non, edible source, Waste, Reewable energy, Methyl esters
  • A. Ebrahimi, G. D. Najafpour (Iran) Pages 114-123
    Microorganisms play an important role in biological treatment processes. Biodegradable organic matter in wastewater would be removed completelyby proper microbial consortia. The mixed culture is either generally present in the wastewater, or is introduced to the target wastewater by mixing it with domestic wastewater or sewage sludge. However, pure cultures bioprocess may be used in certain cases for the removal of specific contaminants. In favorable environmental condition, microorganisms are capable of presenting high efficiency in destruction of pollutants. If environmental conditions such as nutrition, pH, temperature, dissolved oxygen, hydraulic and sludge retention time are suitable and consistent with the nature of process, microorganisms grow and remove organic pollutants through biochemical activities.The aim of this article was to investigate the performance and mechanism of various systems of suspended and attached growth; while the detail of process in different fabricated systems was evaluated. The advantages and disadvantages of NRBC, UASFF, UAPB and normal activated sludge process were discussed. Growth kinetics and COD removal of effluents were also investigated. The result indicated the combination of fluidized and fixed film has created active biogranules which were quite faster and more efficient in treatment of industrial wastewater.
    Keywords: Activated sludge, Fluidized, Fixed film, COD removal, Suspended growth
  • M. Vakili, M. Rafatullah, M. Hakimi Ibrahim, A. Zuhairi Abdullah, B. Salamatinia, Z. Gholami (Malaysia) Pages 124-128
    In the present study, chitosan beads were prepared at different preparation conditions and then applied for adsorption of Reactive Blue 4 (RB4) in a batch adsorption process. Effect of beading parameters such as chitosan concentration, acetic acid concentration and temperature in the removal of RB4 from aqueous solution was investigated. It is found that increasing the concentration of chitosan, acetic acid, and temperature decreased dye removal. The chitosan beads prepared with 2% chitosan and 1% acetic acid concentration at room temperature (30 ± 2 °C) were more suitable for RB4 removal. The beading parameters were found to be effective on the adsorption properties of the prepared adsorbents. Thus, the preparation of chitosan beads at appropriate conditions is a suitable method to improve the anionic dyes adsorption from aqueous solutions.
    Keywords: Chitosan beads, Chitosan concentration, Acetic acid concentration, Dye treatment, Reactive Blue 4
  • R. Alrozi, N. S. Anuar, F. Senusi, M. A. Kamaruddin (Malaysia) Pages 129-136
    In this study, the adsorption behavior of Remazol Brilliant Blue R (RBBR) from aqueous solution by using raw and modified clinoptilolites were investigated. In the experimental work, raw clinoptilolite (R-CL) was treated with Zn(NO3)2 in ethanol and produced zinc-grafted clinoptilolite (Zn-CL).The adsorption experiments were carried out under different conditions of initial concentration (25-250 mg/L), adsorption time (0-2h), solution pH (2-12), and temperature (300-353 K) to determine optimum conditions for the highest RBBR removal. The influence of these parameters on the adsorption capacity was studied using the batch process. The results indicated that the solution pH was observed to be a key factor of the RBBR adsorption process. The maximum dye adsorption was achieved with Zn-CL adsorbent at pH~6 and the corresponding adsorption capacity was found to be 42.2 mg/g, which was higher than R-CL (12.5 mg/g). Lower adsorption capacity of RBBR was found by Zn-CL between pH 8 and 12 opposite to R-CL which showed a marginal increase in adsorption capacity within the same pH range. The results proved that Zn-CL which is a modified clinoptilolite is an effective adsorbent for the removal of RBBR from aqueous solution.
    Keywords: Adsorption, Clinoptilolite, RBBR, Kinetic, Isotherm models
  • S. Khodami, M. Surif, W. O. Wan Maznah (Malaysia) Pages 137-143
    This study was conducted to investigate the ability of Ulva reticulata (Chlorophyta) to remove Cd, Co, Cr, Cu, Fe, Mn, Mg, Pb, V, and Zn from industrial wastewater. A 24 h experiment was performed under laboratory and in situ conditions, which were set up in two places: (1) the industrial area in Bayan Lepas and (2) the coastal area close to Jerejak Island. The initial amounts of metals in U. reticulata were ranked as follows: Mg > Fe > Zn > Mn > Ni > Cu > Cr > Co > Cd = Pb > V. However, after exposure to the experimental conditions for 24 h, the sequence amounts of the metals in the tissue changed. Fe showed the highest uptake in situ with a maximum uptake of 869.0 ± 84.1 µg g−1 dw. Mg demonstrated the maximum uptake in the laboratory, which was 487.8 ± 130 µg g−1 dw. Cd presented the lowest uptake under both in situ and laboratory conditions, which was 0.04 ± 0.027 µg g−1 dw. The uptake capability of U. reticulata depended on the metal concentration in water and under experimental conditions. Overall, this study revealed that U. reticulata can improve the quality of water discharged from industrial areas.
    Keywords: Industrial wastewater, Metal uptake, Ulva reticulata
  • A. Harlina, M. Maheera, I. Norli (Malaysia) Pages 144-148
    This batch study focuses on suitability of laterite soil-pressmud as daily soil cover of landfill. The laterite soil samples were mixed with waste from sugar refinery process, namely pressmud at different percentages of weight ratio (10, 30 and 50%). The batch equilibrium tests were carried out and glaringly showed that the laterite soil-pressmud mixtures have the capability to remove more than 62% of Cr, Cu, Mn, Ni, Pb and Zn concentration in leachate. Meanwhile, the removal efficiency of heavy metals from leachate in the laterite soil alone was lower than 50%. Pressmud alone however showed more than 53% removal. The laterite soil-pressmud mixtures, particularly at 30 and 50 percent of pressmud signify great potential as daily soil cover in reduction of heavy metals migration in landfill leachate.
    Keywords: Daily cover, Heavy metals, Laterite soil, Pressmud
  • L. W. Low, T. T. Teng, N. Mora, B. Azahari (Malaysia) Pages 149-155
    The effects of various carbonization parameters on the COD reduction of Rhodamine B dye aqueous solutions using carbonized Elaeis guineensis frond fiber (EGFF) chars have been studied experimentally. The adsorbent with the particle size of
    Keywords: BET surface area, Carbonization duration, Carbonization temperature, Heating rate, Nitrogen gas flow rate
  • V. S. Jie Wei, C. Han Bing, Agus Saptoroand, Jobrun Nandong (Malaysia) Pages 156-162
    Composting is a biochemical process in a controlled aerobic environment where thermophilic microorganisms stabilize organic waste substrates into valuable humus-like products. Three parameters which are known to affect the composting process including temperature, aeration rate and composting time. This research aims at developing a model to describe the relative influence of different temperatures, aeration rates and reaction time on the composting process and how it affects the final quality of EFB compost produced. EFB samples were mixed with urea as a source of nitrogen and fresh compost as inoculum. The composting process was carried out in a composting test bench for a total of 42 days. The moisture content was found to be significantly affected by temperature and reaction time. Carbon loss was significantly affected by all three factors. Nitrogen content was affected by aeration rate, reaction time as well as interaction between temperature and reaction time. Changes in total ions over time showed a positive correlation with the value of conductivity (Pearson correlation coefficient of 0.853) and the largest reduction in C/N ratio (from 30.2:1 to 17.6:1) was obtained at temperature of 40°C and aeration rate of 0.4 L/min kg. The results of this study could form a basis for palm oil mills to improve the quality of EFB composts produced within a short maturation period and with low C/N ratio.
    Keywords: biodegradation, moisture content, pH, C, N ratio
  • A. J. Asis, M. A. Mohd Arifin, R. Ngteni, S. Tahiruddin, M. O. Abdul Kadir (Malaysia) Pages 163-168
    The palm oil milling industry in Malaysia will be imposed with more stringent treated waste water discharge requirement from currently at BOD of 100 ppm to BOD of 50 ppm and gradually to BOD of 20 ppm. Study was conducted to use Ferrous Sulphate as more economical coagulant to reduce the biological load for tertiary treatment in palm oil mill effluent treatment at laboratory and pilot scale facility to comply with the proposed new requirement. The feed water that was aerobically treated POME with BOD of below 100 ppm was treated with various dosage of ferrous sulphate, from 250 to 2250 ppm. It was found that at laboratory jar-test, the required ferrous sulphate dosage to meet BOD-50 ppm requirement was at 750 ppm while BOD-20 ppm requirement was achieved when the ferrous sulphate dosage was at 1,750 ppm and did not produce hazardous activated sludge. The laboratory findings was scaled-up to pilot scale facility with the capacity of 7 ton/hour to evaluate the physicochemical tertiary treatment based on continuous system. Ferrous sulphate dosage at 1,000 ppm and 1,750 ppm were able to comfortably comply with the discharge limit of BOD-50 ppm and BOD-20 ppm, respectively.
    Keywords: BOD reduction, Ferrous sulphate, POME tertiary treatment
  • T.Y. Ling, L. Nyanti, M. K. Nurul, Safinaz, S. F. Sim, J. Grinang (Malaysia) Pages 169-176
    New development and expansion of cage culture at Batang Ai Reservoir would require investigation of the water quality. Therefore, the objective of this study was to determine the water quality at three existing aquaculture sites, one abandoned site, and one station without cage culture at three different depths. This study was carried out in October 2013 during the rainy season. Water quality was measured in-situ and water samples were collected and analyzed according to standard methods. Results showed that dissolved oxygen concentrations at the surface is sufficient for healthy aquatic organisms. However, dissolved oxygen at 10 m is not suitable for healthy aquatic organisms. All aquaculture sites showed significantly higher conductivity and ammonia-nitrogen at 20 m depth than the station without aquaculture. The aquaculture site that has been abandoned for nine months still showed higher 20 m chlorophyll-a and surface phosphate. Elevated surface, biochemical oxygen demand, phosphate and nitrate were observed at the largest and oldest aquaculture site. Based on the Chl-a concentration, the stations are classified as mesotrophic. This study showed that cage culture activities at Batang Ai Reservoir has impacted the water quality. Hence, further monitoring of water quality in the reservoir needs to be carried out.
    Keywords: aquaculture, dissolved oxygen, nitrogen, phosphorus, chlorophyll, a, trophic state
  • S. K. Yap, I. Muneera, M. I. Syakir, H.H. Zarul, Widad F. (Malaysia) Pages 177-183
    A study was conducted on the stable isotope variation of muscle tissues from selected freshwater fish species from Temenggor Lake and Chenderoh Lake, Perak, Malaysia from December 2014 to March 2015. The objective is to assess the stable isotopes of δ13C to identify the carbon sources and δ15N of fish species from Temenggor and Chenderoh Lake, Perak, Malaysia to infer the trophic position of these fishes. Four types of fish species were analyzed by using stable isotope approach which were Hampala barb (Hampala macrolepidota), Oxygaster cyprinus (Oxygaster anomalura), Peacock Bass (Cichla ocellaris) and Nile Tilapia (Oreochromis niloticus). Stable isotopes of δ13C and δ15N were analysed using an elemental analyser Thermo Finnigan Flash EA 2000 connected to Finningan delta v avantage plus isotope ratio mass spectrometry by a ConFlo II interface. The δ13C values from both lakes implies a C3 phytoplankton as reported from the literature. Based on δ15N values of fish species, O. anomalura occupies the highest trophic level in Temenggor Lake, reflecting its carnivorous feeding habit despite its small size while C. ocellaris was the highest in Chenderoh Lake, implying its predatory behaviour. Further analysis should be carried out to incorporate primary producers and consumers to elucidate the food web in the tropical lake ecosystem. This study provides a reference record for conducting stable isotopes in the food web of tropical lake ecosystem for better management and deeper understanding of the ecosystem functioning.
    Keywords: stable isotopes, Food webs, Freshwater fishes, δ13C, δ15N
  • S. Hena, N. Fatihah, H. Awang (Malaysia) Pages 184-192
    In this study a simple and rapid harvesting method using electro conductive polymer coated saw dust has been presented as a new coagulant for separating Chlorella vulgaris from a diluted suspension. Polypyrrole (PPy) coated saw dust as a novel coagulant was prepared via in-situ polymerization of pyrrole (Py) monomer using FeCl3 oxidant in aqueous medium in which saw dust particles were suspended. The zeta potential of coagulant and C. vulgaris and X-ray photoelectron spectroscopic (XPS) analysis of coagulant were characterized. PPy maintain predominantly positive charge over a wide pH range (2-10) with an isoelectric point 10.4 while, C. vulgaris maintained negative surface charge from pH 5 and onward with isoelectric point 3.8. The microalgae showed the highest separation efficiency at pH 10. The maximal recovery efficiency reached more than 90% for microalgae at a stirring speed of 120 rpm within 7 min. The maximal adsorption capacity of C. vulgaris was 28.8 mg dry biomass/mg-saw dust coated PPy. The concentration factor obtained is higher than 32 which save energy and time associated with microalgal harvesting and allows a reduction in the equipment size necessary for biomass dewatering and improves the feasibility of using these microorganisms in biofuel or wastewater processes.
    Keywords: Microalgae harvesting, Polypyrrole, SD particle, Electrostatic attraction, Chlorella vulgaris
  • R. G. Dolorosa, A. Grant, J. A. Gill (Philippines) Pages 193-202
    The unsustainable harvesting of the reef gastropod Tectus niloticus or ‘trochus’ for the production of ‘mother of pearl’ buttons have led to the collapse of its population and closure of its fishery in some countries. With the costly conservation measure involving the restocking of hatchery produced juveniles in partly protected reefs in the Philippines, this study assessed the abundance of trochus in three types of habitats of three Marine Protected Areas (MPAs) in Palawan, Philippines to document the status of its populations and to propose a more relevant conservation measure. Unguarded and continuously exploited MPAs in the mainland Palawan harboured the least numbers of trochus. By contrast, in effectively protected areas of the Tubbataha Reefs Natural Park (TRNP), densities were quite high with large trochus being abundant in three types of habitats. However, the densities declined the farther the site from the Ranger Station of TRNP. In permanent monitoring sites in TRNP, the abundance declined between 2006 and 2008, with slight recovering trends toward 2010. Sizes of sampled trochus at TRNP in 2008-2010 were significantly larger than in 2006. The presence of recruits at constantly fished MPAs at Palawan on the mainland could lead to population recovery if these areas are effectively spared from fishing for a longer period of time. Restored biodiversity in networks of MPAs could be highly beneficial to the ecosystem, the fisheries and economic sectors.
    Keywords: Abundance, Size structure, Protected area, Harvesting, Tectus niloticus
  • A.A. Nurhanim, I. Norli, N. Morad, H.P.S.A. Khalil (Malaysia) Pages 203-211
    Recycling of Construction and Demolition Waste (CDW) aims to minimize the generation of waste and reduce the dependency on natural resources. The aims of the research are to characterize inorganic element and to determine the leaching behavior of CDW (concrete and gypsum) by means of the leaching test. The analyzed results were compared with the European Union (EU) Landfill Directive to assess their acceptance criteria. Both wastes were found to have elements of Ca, Mg, Fe, Zn, Mn, Pb, Cu, Cd, As, Cr, Se, Ni, CI and SO42-. The highest concentration and variety of inorganic element found in waste gypsum (WG) were SO42->Ca>CI>Mg>Zn>Cu>Fe. X-ray diffractometric (XRD) analysis proved that the WCo was dominated by quartz, calcite, ettringite, cordierite, diopside and the WG was only dominated by gypsum. The leaching behavior of WG demonstrated pH dependent particularly for the elements of Ca, Mg, Fe, Zn, Cu and Mn but only the elements of Ca and Cr in WCo were shown to be pH dependent in the leaching test. The element of SO42- from the WG indicated a higher reading than WCo without the influence of pH. Noticeably, the concentration of SO42- within the WG strongly require regulation and control before it can be utilized as part of raw materials in the production of environmental friendly recycled building materials.
    Keywords: Construction, demolition waste (CDW), Concrete, Gypsum, Leaching behavior, pH