INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY (IJEST)
Year:2011 | Volume:8 | Issue:1 (29)|Papers Count:20

Spatial and temporal fractionation of trace metals and major elements in suspended particulate matter in the Seine River was investigated to study the impact of the increasing urbanization in the Greater Paris Region. Suspended sediments in the Seine River were collected between December 2008 to August 2009 upstream and downstream of Paris. They were subjected to total digestion and sequential extraction procedure certified by the Bureau Communautaire de Référence and trace metals along with major elements were analyzed with inductively coupled plasma mass spectroscopy. Metal enrichment factors increased up to eight folds after the Seine River downstream of the Greater Paris Region showing a significant contribution of urbanization. Enrichment of copper, lead and zinc downstream of Paris are followed by the increase of their reducible fraction of at least 10% implicating an increase in metals associated with iron oxides. The exchangeable fraction, which includes the carbonate-associated metals, is only significant for cadmium, nickel and zinc (more than 2%) while the oxidisable fraction accounts for less than 20 % for the anthropogenic metals downstream except for copper. The metals can be divided to (a) “reducible” group including cadmium, lead, and zinc, associated with more than 60 % of the total Bureau Communautaire de Référence extractable metals to the reducible fraction containing mostly iron oxide phases for the downstream sites. (b) A “distributed” group including chromium, copper, and nickel that are associated to at least 3 different phase-groups: (1) oxides, (2) organic matter and sulphides and (3) mineral phases.

Ultraviolet photolysis and ultraviolet and hydrogen peroxide oxidation of fourteen commonly used pharmaceutical compounds and two personal care products in mixed solution using low pressure ultraviolet lamp was investigated in laboratory batch experiments. Removal of the compounds followed the first-order reaction kinetic. Three distinct impacts of hydrogen peroxide on ultraviolet and hydrogen peroxide oxidation of the compounds (positive, negative and no significant effect) were observed. Removal behavior of the several tested compounds in mixed solution varied significantly than their respective behavior in absence of coexisting compounds. Clofibric acid, diclofenac, fenoprofen, isopropylantipyrine, ketoprofen, phenytoin and triclosan were removed very efficiently (> 96 %) by ultraviolet photolysis alone. Residual hydrogen peroxide during ultraviolet and hydrogen peroxide oxidation was quantitated for the first time. Hydrogen peroxide addition to ultraviolet photolysis was not worthy for majority of the tested compounds as their removal did not increase significantly and very big fractions (> 85 %) of the added hydrogen peroxide (0.29 ~ 1.47 mM) remained unused presumably due to small fluence of the lamp, very small molar absorption for hydrogen peroxide at 254 nm (27.06 /M.cm) and acidic pH of reaction solution (< 5.7). Further exploration on ultraviolet and hydrogen peroxide oxidation with higher fluence lamp and alkaline solution pH will clarify usefulness of the method to treat pharmaceutical contaminated waters.

Due to the negative environmental effects of fossil fuel combustion, there is a growing interest in both improved efficiency in energy management and a large-scale transition to renewable energy systems. Using both of these strategies, a large institutional-scale hybrid energy system is proposed here, which incorporates both solar photovoltaic energy conversion to supply renewable energy and cogeneration to improve efficiency. In this case, the photovoltaic reduces the run time for the cogeneration to meet load, particularly in peaking air conditioning times. In turn, however, the cogeneration system is used to provide power back up for the photovoltaic during the night and adverse weather conditions. To illustrate the operational symbiosis between these two technical systems, this study provides a case study of a hybrid photovoltaic and cogeration system for the Taleghani hospital in Tehran. Three design scenarios using only existing technologies for such a hybrid system are considered here:1) single cogeneration + photovoltaic, 2) double cogeneration + photovoltaic, 3) single cogeneration + photovoltaic + storage. Numerical simulations for photovoltaic and cogeneration performance both before and after incorporating improved thermal energy management and high efficiency lighting were considered. The results show that the total amount of natural gas required to provide for the hospitals needs could be lowered from the current status by 55 % for scenario 1 and 62 % for both scenarios 2 and 3, respectively. This significant improvement in natural gas consumption illustrates the potential of hybridizing solar photovoltaic systems and cogeneration systems on a large scale.

A new cypermethrin degrading strain was isolated from wastewater sludge using enrichment technique. On the basis of morphological, physiological, biochemical characteristics tests and 16S rDNA sequence analysis, the strain was determined to be a Streptomyces species, probably a strain of Streptomyces parvulus, so it was designated as Streptomyces sp. HU-S-01. The strain Streptomyces sp.HU-S-01 is aerobic and optimum growth temperature for the strain was found to be 26-28°C with initial pH range 6.0-9.0 and pH 7.5 was found to be the optimum. This strain can also completely degrade 3-phenoxybenzoic acid within 96 h at the concentration of 50 mg/L. The kinetic constants Vmax, Km, Kcat and Kcat/ Km of enzyme for cypermethrin were 1.236 mmol/min, 6.418 mmol/mL, 13.493 min and 2.102 mL/mol.min, respectively. The degradation products of cypermethrin were identified using gas chromatographmass spectrometric (GC-MS) analysis. The degradation pathway followed by HU-S-01 involves oxidative as well as hydrolyzing. Biodegradation ability of strain Streptomyces sp. HU-S-01 without toxic byproducts reveals its potential for further study as a biological agent for the remediation of soil, water or crops, contaminated with cypermethrin.

Recently, decreasing of fossil fuel reserves and their negative effect on environment have increased the interest in alternative energy sources. One of the alternative energy sources is vegetable oils. In this study, blends of 50 % opium poppy oil – 50 % diesel fuel mixture are tested as alternative fuel on a single cylinder, 4-stroke, air cooled, precombustion chamber diesel engine at different speeds and its effects on engine performance and emissions are investigated. When compared to the diesel fuel as average, engine torque and power decrease at 4 % and 5.73 %, respectively. Specific fuel consumption increases by using of 50% opium poppy oil – 50 % diesel fuel mixture. When compared to the diesel fuel as average, carbon monoxide and nitrogen oxides emissions of 50 % opium poppy oil – 50 % diesel fuel mixture decrease to 15.5 % and 5.9 %, respectively. Diesel fuel–opium poppy oil mixture has been found notably successful and environment friendly as an alternative fuel for diesel engines.

A study of polycyclic aromatic hydrocarbons pollution in roadside soil was conducted in developing city environment of northern India during autumn and winter season to ascertain the contamination levels and their distribution behavior in soil. The concentration of polycyclic aromatic hydrocarbons was determined at ten locations of Jalandhar city, Punjab in India at 1, 2 and 3 m distances from roadside in soil covering all the major traffic intercepts within city. The samples were extracted in acetone and dichloromethane (1:1) using soxhlet extraction. The extracts were then filtered on a silica gel micro column to remove impurities and elute was subjected to GC-FID. The total average concentration (city average) was found to be 4.04 mg/g and 16.38 mg/g during winter and autumn respectively. DiBenzo (ah) Anthracene and Benzo (a) Pyrene were the individual polycyclic aromatic hydrocarbons found in highest concentration at all the intercepts ranging between 0.008 to 28.4 mg/g during winter and 0.01 to 252.55 mg/g during autumn. Average concentration of non-carcinogenic and carcinogenic polycyclic aromatic hydrocarbons during winter and autumn was found to be 2.1 and 6.4 and 4.74 and 35.08 mg/g respectively. The average ratio of non-carcinogenic and carcinogenic Polycyclic Aromatic Hydrocarbons was found to be 1:3 during winter, and 1:7.6 during autumn at most of the intercepts. Total carcinogenic polycyclic aromatic hydrocarbons concentration was found quite high (80 %) in comparison to non-carcinogenic polycyclic aromatic hydrocarbons (20 %) at most of the intercepts.

Separation of metal laden solid wastes for their recycling utilization using passive pulsed air and active pulsing air classifiers was studied. Laboratory investigation showed that the active pulsing air separator performs more efficiently than the passive pulsed air separator due to the ability to accurately control operating parameters. By studying the difference of drag coefficients of the particles moving through the airflow of varying Reynolds numbers, models of the dynamic particle motion were developed and a computer simulation was prepared. Results of the simulation were reported to predict the observed results with artificial tracing spheres being separated by the laboratory equipment. Two different, real world feed materials were separated with the laboratory scale active pulsing air classifier. The discarded catalyst consisting of precious metal components and sintered magnetic beads was separated with the separation efficiency, of 97.6 %. The second real-world feed, electronic scrap crushed to a size of 0.5 to 2 mm, showed a separation efficiency of 92.41 %. At the same time, the grade of the recovered concentrate of metals was above 98 %.

Volatile fatty acids are the most important intermediates in anaerobic digestion, and their degradations are extremely complicated thermodynamically. In this research, syntrophic anaerobic digestion of volatile fatty acids using enriched acetogenic and methanogenic cultures in a batch reactor at mesophilic conditions was investigated. Interactive effects of key microbiological and operating variables (propionic, butyric and acetic acids, retention time and methanogen to acetogen populations ratio) on the anaerobic degradation of volatile fatty acids were analyzed. Acetogenic and methanogenic anaerobes in the granular sludge from an up-flow anaerobic sludge blanket reactor were enriched at mesophilic conditions within a period of four weeks, separately. Enriched cultures were mixed with known proportions and then used in the bioreactor. Experiments were carried out based on central composite design and analyzed using response surface methodology. Four parameters (final concentrations of propionic, butyric and acetic acids and biogas production) were directly measured as response. Also, the optimum conditions for volatile fatty acid degradation were found to be 937.5 mg/L, 3275.5 mg/L, 2319.5 mg/L, 45 h and 2.2 proportions for propionic acid, butyric acid, acetic acid, retention time and methanogen to acetogen populations ratio, respectively (corresponding to maximum volatile fatty acid removal efficiencies and biogas production). The results of the verification experiment and the predicted values from the fitted correlations at the optimum conditions were in close agreement at a 95% confidence interval. The present study provides valuable information about the interrelations of quality and process parameters at different values of microbiological and operating variables.

This study presents the standardization of nutrient concentration, pH and temperature required to decolorize the anerobically treated distillery spent wash using the fungus Cladosporium cladosporioides. Experiments were carried out to measure the decolorization of distillery spent wash effluent and it was found to be effective in acidic environment. From the results it was observed that a maximum color reduction of 52.6 % and Chemichal Oxygen Demand. removal of 62.5 % were achieved. The optimum conditions required for the growth of the fungus was found to be 5 g/L of fructose, 3 g/L of peptone, 5 pH and 35°C. It was also observed that during the process a maximum of 1.2 g of fungal growth was attained. Decolorizing ability of the fungus was confirmed using spectrophotometer and High Performance Liquid Chromatography analysis. Single factorial experimental design was used to optimize the parameters. Apart from decolorization it was observed that fungus also has the ability to degrade the spent wash efficiently. This investigation could be an approach towards control of environmental pollution and health hazards of people in and around the distillery unit.

Water supply for consumption is one of the crucial objectives of water supply systems. Using of excessive fertilizer is a main source of nitrate content in water. The high amounts of nitrate in water have a determinable effect on the environment which must be removed due to drinking and industrial water standards. The purpose of this study is nitrate removal from aqueous solution by Electrocoagulation process. The applied pilot was comprised of a reservoir, electrode and power supply. In this study pH, electrical potential difference, nitrate initial concentration, total dissolved solid, kind of electrode, electrode connection methods and number of electrode were studied. Moreover, obtained optimum conditions were tested on Kerman water. The results showed that the electrocoagulation process can reach nitrate to less than standard limit. pH, electrical potential difference, total dissolved solids and number of electrodes have direct effect and initial concentration of nitrate has reverse effect on nitrate removal. This study also showed that under optimum condition, nitrate removal from Kerman water distribution system was 89.7 %. According to the results, Electrocoagulation process is suggested as an effective technique in nitrate removal.

Biological technologies for wastewater remediation techniques employed to remove contaminants in urban stream water are increasingly receiving attention worldwide. The purpose of this study was therefore to determine the concentrations of lead, cadmium, copper, zinc, manganese and iron in algal biomass and establish the feasibility of using algae in phytoextraction and bio-monitoring of environmental quality. Analysis of algal biomass samples in the Nakivubo urban stream ecosystem, Kampala, Uganda, showed that there was contamination by lead, cadmium, copper and zinc as indicated by enrichment factor and pollution load index values. It is suspected that industrial and vehicular emissions are the major sources of these pollutants. Calculated bio-concentration factor was ³ 1000 but with low concentration thresholds in each element, suggesting that algal biomass was a very good heavy metal accumulator. The bio-concentration values in algal biomass were found to be in the order of copper > zinc > lead > cadmium in the Nakivubo Channelized stream. In conclusion, algae can be a promising aquatic bio-filter plant for phytoextraction and bio-monitoring of polluted urban stream ecosystems and wastewater.

The purpose of this study was to evaluate the effectiveness of a commercial biofungicide such as Trichomix-HV in controlling damping-off disease in cucumber seedlings of greenhouses. In this regard, 504 fungal isolates were collected from greenhouses at 31 districts in city of Jiroft in Iran. Pythium aphanidermatum, P.ultimum, P. irregulare, Phytophthora drechsleri, and Ph. melonis accounted for 9.9 %, 8.3 %, 4.5 %, 4.9 %, and 21 % of total isolates collected, respectively. Isolates of P. aphanidermatum obtained from commercial cucumber in greenhouses were tested in vitro and under greenhouse conditions for sensitivity to chemical and biological treatments. To this aim, Trichomix-HV a commercial formulation of Trichoderma harzianum strain T969 and the fungicides Metalaxyl and Metalaxyl MZ were amended into the culture medium as well as into sterilized or non-sterilized greenhouse soils inoculated by the pathogen and containing plants at the seedling stage. Trichomix-HV significantly (P < 0.001) reduced seedling infection at a rate of 82 % when applied into soil medium at a concentration of 107 conidia ml/L and reduced vegetative growth of Pythium aphanidermatum in vitro. The result from this study shows that Trichomix-HV can be effectively used as a biocontrol agent for controlling damping-off cucumber seedlings and having the potential to replace chemical fungicides as a mean of disease control.

In this study, key uncertainty sources analysis was undertaken for a dynamic water model using a First order error analysis method. First, a dynamic water quality model for the Three Gorges Reservoir Regions was established using data after impoundment by the environmental fluid dynamics code model package. Model calibration and verification were then conducted using measured data collected during 2004 and 2006. Four statistical indices were employed to assess the modeling efficiency. The results indicated that the model simulated the variables well, with most relative error being less than 25 %. Next, input and parameter uncertainty analysis were conducted for ammonia nitrogen, nitrate nitrogen, total nitrogen, and dissolved oxygen at 3 grid cells located in the upper, middle and downstream portions of the research area. For the nitrogen related variables, input from Zhutuo Station, the Jialingjiang River, and the Wujiang River were the main sources of uncertainty. Point and nonpoint sources also accounted for a large ratio of uncertainty. Moreover, nitrification contributed some uncertainty to the estimated ammonia nitrogen and nitrate nitrogen. However, reaeration was found to be a key source of uncertainty for dissolved oxygen, especially at the middle and downstream reaches. The analysis conducted in this study gives a quantitative assessment for uncertainty sources of each variable, and provides guidance for further pollutant loading reduction in the Three Gorge Reservoir Region.

The wastewater discharged by poultry slaughterhouse industries are characterized mainly by high biochemical oxygen demand, high suspended solids and complex mixture of fats, proteins and fibers requiring systematic treatment prior to disposal. In this study, the performance of an upflow anaerobic filter reactor for treating Indian poultry slaughterhouse wastewater under low upflow velocity of 1.38 m/day at mesophilic temperature (29-35°C) was investigated. The reactor was inoculated with anaerobic non-granular sludge from an anaerobic reactor treating the poultry slaughterhouse wastewater. The reactor took 147 days for complete start-up with removal efficiencies of total chemical oxygen demand and soluble chemical oxygen demand of 70 and 79 % respectively. The maximum total chemical oxygen demand removal efficiency of 78 % was achieved at an organic loading rate of 10.05 kg/m3/day and at an hydraulic retention time of 12 h. The average methane content varied between 46 and 56 % and methane yield at maximum removal efficiency was 0.24 m3 CH4 /kg CODremoved.day. Sludge granules of 1-2 mm were observed in between the packing media. Scanning electron microscope analysis revealed that sludge granules are composed of clumps of Methanosarcina clustered with less intertwined Methanosaeta fibre of granules. The lower velocity used in this study has achieved better performance of the reactor by creating active microbial formation with stable pH upto an organic loading rate of 14.3 kg/m3/day. This has proved that the poultry slaughterhouse wastewater can be treated using anaerobic filter reactor under low upflow velocity.

The studies carried out throughout the world have indicated that there are differences between environmental attitudes and environmentally responsible behaviors of undergraduate students. In what ways the environmental attitudes and behaviors of the students who will protect and manage the resources of the country in the future have changed is an important issue? This study was aimed at determining the environmental attitudes and environmentally responsible behaviors of the undergraduate students of Abant Ýzzet Baysal University toward environmental issues. In addition, the effects of the faculty in which the students are enrolled, locality and gender on the determined environmental attitudes and environmentally responsible behaviors of the students were investigated. The data were gathered from 507 students in 2005. To explain the environmental attitudes and environmentally responsible behaviors of undergraduate students toward environmental issues, factor analysis was used with Varimax Rotation method. To determine the changes of the environmental attitudes and environmentally responsible behaviors of the students with regard to the faculty, locality and gender, one-way analysis of variance was used. According to the results, students highly support the environmental attitudes and highly participate only in consumerism behaviors. Finally, it was determined if faculty and gender had an effect on the environmental attitudes and behaviors of the students.

The purpose of this study was to assess the relationship between psychological stresses and noise stresses on printery workers in Tehran, Iran. Hence, 267 workers were randomly selected. The Leq and Lmax were measured and the psychological stresses such as depression, anxiety, aggression and job satisfaction were also studied by the relevant questionnaires. The data were statistically analyzed by Pearson correlation test. The results demonstrated that there was no significant statistical relationship between noise and psychological stresses. In addition, by using Spearman regression method, the influence of variables such as age, gender and job history on psychological stresses caused by Leq and Lmax was studied and the results only revealed that the aggression caused by Leq increased in young personnel (P=0.02) as well as, anxiety caused by Lmax increased accompanied by increasing the job history and age of the workers (P=0.002 and P=0.007). Therefore, more variables must be taken into consideration to judge about noise induced psychological stresses in workplaces.

The influent concentration has a great effect on nutrients removal efficiency in vertical subsurface flow constructed wetland systems, but treatment performance response to different C: N: P ratios in the influent are unclear at present. At the first growing seasons, the effects of the plants present or not, season, the different C: N: P ratio in influent condition and their interaction on treatment performances were studied in the planted or the unplanted wetlands in greenhouse condition. Each set of units was operated at hydraulic loading rates of 40 L/d. Low, medium and high-strength (100, 200, 400 mg/L of chemical oxygen demand or 20, 40, 80 mg/L total nitrogen) synthetic sewage were applied as influent. According to the first growing season results, the average removal efficiencies for the unplanted and the planted wetlands were as follows: chemical oxygen demand (44-58 % and 55-61 % respectively), total nitrogen (26- 49% and 31-54 %) and total phosphorus (36-64 % and 70-83 %). The both wetlands system was operated as an efficient treatment system of highest average removal rates of both chemical oxygen demand and total phosphorus when medium-strength synthetic sewage were applied. When high strength synthetic sewage was applied, the planted wetlands usually had a higher nutrients removal rates than the unplanted over the study period. The plants grew well under any high loading treatment over the study period. Anyhow, it also proved that the wetland systems have a good capacity to treat different strength wastewater in greenhouse condition.

Aerobic fixed bed bioreactors were used to study and compare biostimulation and bioaugmentation for remediation of soil contaminated with spent motor oil. Bioaugmentation using consortium of bacteria and biostimulation using inorganic fertilizer and potassium dihydrogen orthophosphate were investigated. The bioremediation indicators used were the oil and grease content removals, total heterotrophic bacteria counts and carbon dioxide respiration rates. Results showed that biodegradations were very effective with 50, 66 and 75 % oil and grease content removal efficiencies for control, bioaugmentation and biostimulation respectively after ten weeks. Carbon dioxide respiration followed similar pattern as the oil and grease content removals. Biostimulation option has the highest carbon dioxide generation (6 249 mg/kg) and the control with the least (4 276 mg/kg). Therefore, the biostimulation option can be used to develop a realistic treatment technology for soils contaminated with spent motor oil.

This study was focused on nettle ash as an alternative adsorbent for the removal of nickel (II) and cadmium (II) from wastewater. Batch experiments were conducted to determine the factors affecting adsorption of nickel (II) and cadmium (II). The adsorption process is affected by various parameters such as contact time, solution Ph and adsorbent dose. The optimum pH required for maximum adsorption was found to be 6. The experimental data were tested using Langmuir, Freundlich and Tempkin equations. The data were fitted well to the Langmuir isotherm with monolayer adsorption capacity of 192.3 and 142.8 mg/g for nickel and cadmium, respectively. The adsorption kinetics were best described by the pseudo second order model. The cost of removal is expected to be quite low, as the adsorbent is cheap and easily available in large quantities. The present study showed that nettle ash was capable of removing nickel and cadmium ions from aqueous solution.

Biodiesel production is worthy of continued study and optimization of production procedures due to its environmentally beneficial attributes and its renewable nature. Heterogeneous transesterification is considered to be a green process. The process requires neither catalyst recovery nor aqueous treatment steps and very high yields of methyl esters can be obtained, close to the theoretical value. However, heterogeneously catalyzed transesterification generally requires more severe operating conditions, and the performance of heterogeneous catalysts is generally lower than that of the commonly used homogeneous catalysts. Heterogeneous catalysis for biodiesel production has been extensively investigated in the last few years. Many metal oxides have been studied for the transesterification process of oils; these include alkali earth metal oxides, transition metal oxides, mixed metal oxides and supported metal oxides. The use of solid metal oxides as catalysts in oil transesterification is well established, accordingly, researchers’ attempts are now focused on how to attain the highest catalyst activity. Catalyst activity is a function of its specific surface area, base strength and base site concentration. High specific surface area, strong base strength and high concentration of base sites are characteristics of an active transesterification catalyst. This review provides a brief overview of the different metal oxides frequently used in the process of transesterification of oils for the production of biodiesel with special reference to the various methods of catalyst preparation and catalyst characterization. Reaction conditions and catalyst leaching analysis are also highlighted. Finally, concluding remarks regarding catalyst selection and catalyst preparation steps are provided.