International Journal Of Environmental Research
Volume:4 Issue: 4, Autumn2010

It has been known for years that microbial surface active agents have a wide range of applications not only in oil spill environment but also in many industries. Their properties including: (i) changing surface active phenomena, such as lowering of surface and interfacial tensions, (ii) wetting and penetrating actions, (iii) spreading, (iv) hydrophylicity and hydrophobicity actions, (v) microbial growth enhancement, (vi) metal sequestration and (vii) anti-microbial action attract the biotechnologist’s attention to be substituted instead of synthetic ones. There are many advantages of biosurfacants in comparison with chemically synthesized counterparts like biodegradability, generally low toxicity, biocompatibility and digestibility, availability of cheap raw materials, acceptable production economics, use in environmental control, specificity and Effectiveness at extreme temperatures, pH and Salinity. Hydrophobic petroleum hydrocarbons require solubilization before degradation by microbial cells. Surfactants can increase the surface area of hydrophobic materials, such as oil spills in soil and water environment, thereby increasing their water solubility. Hence, the presence of surfactants would increase biodegradation of complex hydrocarbons like asphaltenes and resins. Increasing supply of heavy crude oils, bitumens, distillation vacuum residue in most of oil producing countries has increased the interest in transportation and conversion of the high-molecular weight fractions of these materials into refined fuels and petrochemicals and also the interest of conversion of heavy fraction of crude oil like vacuum distillation residue to more valuable components.

This paper addresses a multi-criteria decision based methodology to develop a road network cost function for route finding analysis in a Geographic Information System (GIS). Over the years, several studies relating to route planning process in GIS and Intelligent Transportation Systems (ITS) have been conducted, most of which rely on the use of one-dimensional variables like distance or time as a cost function. This paper, in contrast, investigates multi-dimensional variables to define the cost function using a multicriteria decision making approach. To this end, first additional realistic variables which have quantitative as well as qualitative characteristics are taken into account. These include climate, sight-seeing information, road type, and so on. Second, they are combined using a Multi-Dimensional Cost Model (MDCM) using the Analytical Hierarchical Process (AHP). The models developed were implemented and closely evaluated in northern parts of Iran. The resulting routs showed to be more accurate than those obtained utilizing one-dimensional cost functions.

This study aimed to find an appropriate way to minimize water utility in the petrochemical and petroleum industries. For this purpose، Tehran oil refinery was chosen to analyze feasibilities of regeneration، reuse and recycling in the water network. In this research، two key contaminants including COD and hardness were analyzed. Amount of freshwater was reduced about 180 m3/h (53%) and 216. 88 m3/h (63%) regarding COD and hardness respectively. In the next stage، two mentioned contaminants were analyzed simultaneously based on the mass transfer constraints. Results showed that the amount of required water was reduced from 340 m3/h to 197. 12 m3/h that was about 42%. Analyzing both methods clearly demonstrated that amount of required water would be determined by mass transfer of COD. In addition، the method based on multiple contaminants gave more precise results rather than single contaminant.

Allium cepa bulbs were germinated in pots for three days on treatment area on which 380 kV high voltage power lines are passing. Ten bulbs were set up for each treatment area (0 m (meter), 10 m, 25 m, 50 m and 100+ m for control from power lines). Triticum baeoticum Boiss. subsp. baeoticum seeds were collected at same distance from power lines on planted field. Ten seeds from each area were germinated in Petri dishes for three days in laboratory. The treatment groups were compared with the control group for mitotic index and chromosome aberrations. Data obtained showed that electromagnetic fields from high voltage power lines increased the mitotic index and chromosome aberrations.

Besides human dental and skeletal fluorosis, drinking water above permissible levels of fluoride is known to cause a wide range of adverse health effects. In this study, the adsorption of Fluoride from aqueous solution onto pretreated zeolite has been studied by using batch test. The large surface area of natural zeolite (i. e., clinoptilolite from Miyaneh region, Iran) was utilized to create active sites for fluoride sorption by exchanging Na+-bound zeolite with Fe3+ and Al3+ ions. In this study, the effects of variables such as contact time, and Fluoride concentration have been investigated. Since the chemistry quality of groundwater varies from point to point, the effects of pH and electrolytes such as bicarbonate, chloride and sulfate on fluoride uptake are studied too. The performances of the Fluoride adsorption with the natural zeolite (i. e., non modified zeolite) were compared with the pretreated zeolite. Factors from the solution chemistry that affected fluoride removal from water were the solution pH and bicarbonate content. Acidic pH was the better condition for fluoride adsorption and the bicarbonate content cause higher pH values and thus diminished the affinity of the adsorption sites for fluoride. Comparing natural and deionized water with each other it was observed that the existence of onions in natural samples has an intervening effect on absorption rate of fluoride. In overall, among the aforementioned Pretreated Zeolites (i. e., Al3+ and Fe3+ -modified zeolites), Al3+ was particularly found to create adsorption media with high capacity and specificity for fluoride.

Two potassium oxalate doped TiO2 samples, designated as K1-TiO2 and K2-TiO2, were synthesized by the base-catalyzed sol-gel process. These samples were impregnated into rubber sheets. Two commercial TiO2 samples, anatase and Degussa P25, were used as reference materials with which the synthesized samples were to be compared. Anatase and P25 were also impregnated into rubber sheets and designated as Imp-Ana and Imp-P25, respectively. Methylene blue solution was effectively decolorized by these four impregnated sheets. Imp-K1 and Imp-K2 sheets could turn dye solutions to colorless in 3 h and remained at that point until reaching 6h. For the Imp-Ana and Imp-P25 sheets the decolorization rate was slower but increased continually until reaching their maximum at 6h (colorless). The mode of decolorization for the Impsynthesized TiO2 was mainly based on adsorption with a small contribution from the photocatalytic reaction while the reverse was observed for the Imp-commercial TiO2. The surface of the used Imp-synthsized TiO2 sheets became covered with dye after several uses but it could be cleaned by regeneration with H2O2 and UV light. After recycling the cleaned sheets could be reused many times to decolorize the dye solution.

The river Kabini which is tributary of Cauvery drains through industrial area at Nanjangud, Karnataka. Out of the sediment load carried by the river, 2micron the clay fraction was analyzed for total heavy metal contents and advanced statistical techniques such as cluster analysis and correlation matrix were applied in order to investigate the source of heavy metal concentration in the sediments. The river carriesnatural and anthropogenic pollutants, mainly heavy metal concentration of Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn which are released from industrial effluents, agricultural return flows and domestic sewage. The heavy metals find their residence in the colloidal form in water and in 2micron clay fraction in the river bed sediments. Systematic sampling of the river bed sediments at predefined locations has revealed that the metal accumulation is very close to normal and also beyond threshold limits. Compared with the maximum background values in Kabini river sediment, Pb was the highest in terms of contamination level, especially at point of influx of paper mill effluents, followed by Zn and Cu.

As the main actor of implementing energy saving and pollution abatement, corporations and their response to the policy are studied in this paper. We find that corporate properties as scale, ownership, current environmental performance on energy using and pollution, target market and listed situation have impact on the corporate responding conduct and progress. Especially, current environmental performance has strong relationship with corporate policy responding performance, corporations with low energy efficiency performed poorly to energy saving and those with heavy pollution level performed below average for pollution abatement. It implicates that the national policy could contribute a lot to outdating production facilities less environment-friendly under strict implementation.

The aim of the study is to determine the major source and extent of metal pollution in the vicinity of Dashkasan gold mine. Dashkasan mine has resulted in extensive contamination of soils by Arsenic (As) and potentially toxic ore-related elements including Mercury (Hg), Antimony (Sb) and Cadmium (Cd). Soils samples were collected and analyzed for As, Cd, Hg, Pb and Sb. The concentration of each heavy metal is controlled by different parameters (soil pH, iron and aluminum oxide content, clay content, organic matter and cation exchange capacity). The maximum content in the soils were 485, 3.2, 100, 2710 and 640 mg/kg for As, Cd, Hg, Pb and Sb, respectively. In particular, the extracted concentration of As, Cd, Hg and Sb are in excess of the tolerable levels. Positive correlation with organic matter and clay content but not with pH has been observed for most of elements analyzed in this study. Enrichment factor (EF) analysis and cluster analysis (CA) highlighted the lithogenic origin of heavy metals. It also revealed the need for detailed geochemical surveys in the future in order to decrease the uncertainty of discrimination between lithogenic and anthropogenic origin of metals of interest.

The aim of this research was to optimize bioremediation of seawater samples spiked with 1000 mg/L crude oil for removal of n-alkanes (C12H26 to C34H70). Bioaugmentation experiments were performed at laboratory scale: each bioreactor contained 250 ml dispersed crude-oil-contaminated seawater, indigenous acclimatized microorganism and nitrogen and phosphorus at concentrations based on central composite design (CCD) calculations. Three independent variables, time, nitrogen and phosphorus, were investigated and the experimental data obtained were fitted to a second-order polynomial mathematical model with multiple regressions. The obtained Model F-value of 97.12 and probability F <0.0001 implies the model is significant. Hydrocarbon analyses were carried out using a gas chromatograph equipped with flame ionization detector (GC/FID). During 28 days of experimentation, a maximum of 85.35% total n-alkane removal was observed. Numerical optimization was achieved based on desirability functions. Using 188.71 mg/L nitrogen and 18.99 mg/L phosphorus, design of experiment (DOE) software predicted 91.00% removal. A removal of 92.04% was observed experimentally, in close agreement with the predicted value.

Determination of physical properties of municipal waste compost is necessary to obtain the parameters related to designing and constructing a suitable pelleting machine for producing compost pellets. The purpose of this study is determining some physical properties such as; bulk density, coefficient of friction, porosity, angle of repose for compost and density and expansion for compost pellets. These parameters are determined at three moisture content level (15, 20 and 25 %), four particle sizes (normal size, 10, 30 and 100) and three pressure level (23.4, 36 and 47.7 MPa) with three replications. According to the table of analysis of variance (ANOVA), effect of mesh size on angle of repose using emptying method was significant, but for filling method was not (P=0.01). The effect of mesh size on friction coefficient using four surfaces, was significant (P=0.01). It was determined that the effect of particle size, moisture content and pressure on density of pellets was significant (P=0.01). Also using compost with low porosity, particle size at 100, moisture content at 25% and pressure at 47.7 MPa will results producing best pellets.

This paper deals with the planning of rehabilitation of spoils of asbestos mine in NW Greece with the name MABE in Prefecture of Kozani. For this purpose a detailed ecological research has taken place in the wider area in order to estimate the prevailing environmental (site) conditions. The spoils heaps are characterized by very steep slope inclination (80-90%). In order to improve the stability of the area, in cooperation with civil engineers of our scientific team, a minimization of slope inclination to 39-43% had been decided. For the avoidance of erosion hazard, broad terraces (8-12 m width) and small terraces (1.2 m width) must be constructed. After these works the whole surface of spoils will be covered by topsoil of 40 cm depth. On this topsoil the suitable trees and shrubs species will be planted. The list of these species is the result of detailed research in the mine and the surrounding area. The tree species Pinus nigra, Robinia pseudoacacia, and Quercus pubescens have proposed as dominant species and Acer campestre, Carpinus orientalis, Ostrya carpinifolia, Fraxinus ornus, Celtis austalis and Sorbus aucuparia as secondary tree species.

Considering rapid growth and migration, higher accumulation of communities along with the high number of shopping trips in mega cities such as Tehran brings environmental consequences like excessive amounts of energy use, air pollution and massive urban congestions in all urban trips ending to shopping areas. The present study has been performed in Tehran, capital of Iran in 2009-2010. With the advancement of information, communication technology great access to the electronic devices such as internet, telephone and cell-phone had showed a remarkable increase. Moreover, as a result, the governmental support for elimination or modification of trips through application of tele-presence in various activities has been also developed. The study has investigated the willingness of people in changing their shopping habit from physical to electronic form. A comprehensive questionnaire was designed based on various demographical, geographical and technological competences. For this purpose, final data were collected from 3580 respondents including customers, sellers and governmental sectors in order to achieve the present situation of e-shopping activity in Tehran. Furthermore, cluster analysis were performed and the results showed a significant relationship between eshopping activities and demographic elements such as; income, education, occupation, marital status. Besides, e-shopping activities have a strong correlation with geographic distributions like distance and time to shopping areas as well as technological competence such as time spent, working, browsing on the net plus the mode of connection. Finally, in order to find out e-shopping management strategy in Tehran, the SWOT analysis along with QSPM and SPACE matrices were performed. In this regard, internal and external factors were gained 3.03 and 2.99, respectively. Subsequently, 22 strategies were developed and the scores of each strategy were defined. Space matrix was also indicated that the e-shopping strategy grows to suggested competitive strategy type.

Heavy metals in the surface sediments of the two coastal ecosystems of Cochin, southwest India were assessed. The study intends to evaluate the degree of anthropogenic influence on heavy metal concentration in the sediments of the mangrove and adjacent estuarine stations using enrichment factor and geoaccumulation index. The inverse relationship of Cd and Zn with texture in the mangrove sediments suggested the anthropogenic enrichment of these metals in the mangrove systems. In the estuarine sediments, the absence of any significant correlation of the heavy metals with other sedimentary parameters and their strong interdependence revealed the possibility that the input is not through the natural weathering processes. The analysis of enrichment factor indicated a minor enrichment for Pb and Zn in mangrove sediments. While, extremely severe enrichment for Cd, moderate enrichment for Zn and minor enrichment of Pb were observed in estuarine system. The geo accumulation index exhibited very low values for all metals except Zn, indicating the sediments of the mangrove ecosystem are unpolluted to moderately polluted by anthropogenic activities. However, very strongly polluted condition for Cd and a moderately polluted condition for Zn were evident in estuarine sediments.

Infrastructure development often leads to considerable changes in the land use. These changes are major causes of habitat fragmentation and ecosystem loss. Moreover, decrease of the environmental impacts on biodiversity is among the most important objectives of sustainable development. For this purpose, Environmental Impact Assessment (EIA) along with the other appropriate tools can be applied to identify and predict the magnitude of such problems. Biodiversity Impact Assessment (BIA) as a specific disciplinary tool could be useful to identify the actual impacts on biodiversity within Environmental Impact Assessment. This tool with the assistance of Geographic Information system (GIS) techniques evaluates the data in a comprehensible way. In this paper, a brief case study dealing with the assessment of road alternatives has been carried out to demonstrate the efficiency of BIA. It is found that according to vegetation and wildlife maps, ecosystem loss and fragmentation score of proposed road are more than the existing one. On the basis of the assessment results, the authors also stated that application of BIA in Iran with an exclusive biodiversity is essentially needed.

In this study a machine learning algorithm was applied in order to develop a predictive model for the changes in phytoplankton biomass (chlorophyll a) in the lower Nakdong River, South Korea. We used a “Hybrid Evolutionary Algorithm (HEA)” which generated model consists of three functions ‘IF-THENELSE’ on the basis of a 15-year, weekly monitored ecological database. We used the average monthly data, 12 years for the training and development of the rule-set model, and the remaining three years of data were used to validate the model performance. Seven hydrological parameters (rainfall, discharge from four multi-purpose dams, the summed dam discharge, and river flow at the study site) were used in the modeling. The HEA selected reasonable parameters among those 7 inputs and optimized the functions for the prediction of phytoplankton biomass during training. The developed model provided accurate predictability on the changes of chlorophyll a (determination coefficients for training data, 0.51; testing data, 0.54). Sensitivity analyses for the model revealed negative relationship between dam discharge and changes in the chlorophyll a concentration. While decreased dam discharge for the testing data was applied; the model returned increased chlorophyll a by 17-95%, and vice versa (a 3-18% decrease). The results indicate the importance of water flow regulation as specific dam discharge is effective to chlorophyll a concentration in the lower Nakdong River.

Petrochemical Industries are potentially capable of impacts on environment due to the essence of the activities and producing waste water, pollutant emissions and hazardous wastes. This case study has considered the environmental adverse impacts of petrochemical industries on existing habitats in Mahshahr Economic Special Zone with respect to the regional significant biological diversity and ecological valuable species. When results from regional estuary sampling as well as impacts by petrochemical industries pollutants has been analyzed and studied. Then affected ecosystems have been prioritized using Analytic Hierarchy Process (AHP) method, Expert Choice software and Eigenvector technique. Studies outcomes show that, with regard to petrochemical industries pollutants, especially waste waters including heavy metals, oil and grease, Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), along with criteria defined in AHP method such as ecological and protecting value, estuaries are most affected ecosystems in the region. On the other hand, types of fishes and benthic, such as Decapods, Gastropods and Tanaida have been highly affected by the petrochemical industries activities consequents. It is concluded that, heavy metals, oil and grease, deposit into the environment, are the most important pollutant sources for the regional estuaries which should be controlled.

Electroplating industry wastewater (EIW) characterized by high chemical oxygen demand (COD) is a big source of water and air contamination with heavy metals. The formation of cyanide complex with heavy metals is responsible for its elevated COD. The concentration of heavy metals in EIW can be removed by the use of different precipitating agents (sulfide and hydroxide). But the major bottleneck in the removal of these metals is the presence of cyanide in EIW resulting in chelation with all the metals that are soluble in water. The present work focused on, the treatment of EIW containing Cr, Ni, Zn and CN and the optimization of dosage concentration which was reliable for the dissociation of cyanide complex for maximal removal efficiency. We used hydroxide, sulfide and carbonate precipitation from different precipitating agents (NaOH, Ca (OH)2, CaCO3 Na2S5H2O, NaHS and NaHSO3). Sulfide precipitation was a viable option for the treatment of EIW as compared to hydroxide and carbonate precipitation. Moreover, COD reduction capacity of sulfide precipitation was higher than others. It was also found that Ni and Cr made a complex with cyanide that halted the removal efficiency while there was no evidence for Zn complexation; otherwise fragile complexation was evidenced.

Two different methods of Bayesian segmentation algorithm were used with different band combinations. Sequential Maximum a Posteriori (SMAP) is a Bayesian image segmentation algorithm which unlike the traditional Maximum likelihood (ML) classification attempts to improve accuracy by taking contextual information into account, rather than classifying pixels separately. Landsat 7 ETM+ data with Path/Row 186-26, dated 30 September 2000 for a mountainous terrain at the Polish - Ukrainian border is acquired. In order to study the role of thermal band with these methods, two data sets with and without the thermal band were used. Nine band combinations including ETM+ and Principal Component (PC) data were selected based on the highest value of Optimum Index Factor (OIF). Using visual and digital analysis, field observation data and auxiliary map data like CORINE land cover, 14 land cover classes are identified. Spectral signatures were derived for every land cover. Spectral signatures as well as feature space analysis were used for detailed analysis of efficiency of the reflective and thermal bands. The result shows that SMAP as the superior method can improve Kappa values compared with ML algorithm for all band combinations with on average 17%. Using all 7 bands both SMAP and ML classifications algorithm achieved the highest Kappa accuracy of 80.37 % and 64.36 % respectively. Eliminating the thermal band decreased the Kappa values by about 8% for both algorithms. The band combination including PC1, 2, 3, and 4 (PCA calculated for all 7 bands) produced the same Kappa as bands 3, 4, 5 and 6. The Kappa value for band combination 3, 4, 5 and 6 was also about 4% higher than using 6 bands without the thermal band for both algorithms. Contextual classification algorithm like SMAP can significantly improve classification results. The thermal band bears complementary information to other spectral bands and despite the lower spatial resolution improves classification accuracy.

As one way to approach industrial symbiosis, environmental infrastructure sharing is principally concerned with providing an integrated environmental utility system for clustered firms. It is based on the assumption that environmental infrastructure sharing can improve the regional competitive advantage by reducing overall cost and improving environmental performance. In order to verify the assumption, the research examines the cost-effectiveness of wastewater treatment system of China-Singapore Suzhou Industrial Park between the isolated model and sharing one. The results show that the sharing mode can greatly reduce the overall cost and furthermore provide competitive advantage comparing to the isolated one. In addition, it also improves the overall environmental performance and enforces the cooperation among clustered companies, which creates a good integrated image and attracts more and more excellent enterprises to join in.

In order to decrease the discharge from sulfide mine flotation plants, treatment and reuse approaches based on our previous wastewater monitoring experiments were explored in these plants. The flotation wastewater was collected from the case plant and was treated with coagulation sedimentation and activated carbon adsorption. Then, the effluent was examined for reuse in the flotation process. Furthermore, the effluent was also treated with sodium hypochlorite oxidation to avoid pollution in case effluent happened to be discharged accidently. The results showed that flotation wastewater pollutants could be eliminated effectively and reuse of the effluent did not cause adverse effects, during the six-year application of this procedure. In addition, flotation reagent consumption was greatly reduced, since the effluent containing mostly foaming agents could be reused. Thus, this method proved to be environmentally friendly due to the decreased use of fresh water as well as being economically beneficial.

In this study, under the constraint of resource-saving and environment-friendliness objective, based on multi-agent genetic algorithm, multi-objective spatial optimization (MOSO) model for land use allocation was developed from the view of simulating the biological autonomous adaptability to environment and the competitive-cooperative relationship. The model was applied to solve the practical multi-objective spatial optimization allocation problems of land use in the core region of Changsha, Zhuzhou, Xiangttan city cluster in China. The results has indicated that MOSO model has much better performance than GA for solving complex multi-objective spatial optimization allocation problems and it is a promising method for generating land use alternatives for further consideration in spatial decision-making.

There are many potential sources of stormwater pollutants in urban areas; one of these sources is gas stations, which are numerous and spread city-wide. A study was conducted to evaluate the water quality of runoff from gas stations in the city of Tijuana, Mexico. Pollutant loads in runoff from gas stations in the study area were higher than in other published studies. The estimated loads from gas stations of oil and grease (OG), total suspended solids (TSS) and chemical oxygen demand (COD) were 39.9, 265.3 and 168.6 Kg/ha, respectively. These values of OG, TSS and COD were 57, 41 and 18 times higher than the values reported in another similar study conducted in the US. The possible reasons for these differences may lie in the different cleaning processes utilized in gas stations, in the mechanical conditions of the cars that enter the sites and the urban characteristics surrounding the gas stations. The results from this study show that runoff from gas stations can be a main contributor of pollutants such as suspended solids, heavy metals, oil and grease to stormwater and water bodies.

In the industrial area of Elefsis, Greece, aerosol samples from the atmosphere were collected using a stacked filter unit sampler, which separates the airborne particulate matter into coarse (PM2.5-10) and fine (PM2.5) size fractions. The samples collected during the period January 2005 to March 2006, were analyzed by anodic stripping voltammetry (ASV) and inductively coupled plasma atomic emission spectrometry (ICP-AES) to determine the fine and coarse particulate concentrations of the heavy metals Zn, Pb, Cd, Cu, Fe, Mn and Ni. Concerning the elements Pb, Cd and Ni regulated by the European Union, annual average concentrations were lower than the prospective assessment thresholds, while concentration levels of Mn were in compliance with the values proposed by the World Health Organization. The concentrations of PM10 particulates were about two times as that of the PM2.5 particulates. Additionally, the ratio of fine (PM2.5) to coarse (PM2.5-10) particle concentrations was 0.44, indicating enrichment in the coarse particulates. Fe and Zn concentrations were mostly in the coarse particulate mode. Furthermore, the Pb/Cd average ratio in coarse and fine airborne particulates suggests that Pb is emitted by car exhausts and mainly industrial sources. Moreover, correlation analysis between airborne particulate matter (PM) and toxic elements was carried out to investigate the sources that affect the presence of these elements in coarse and fine particulates.

Solid waste pollution، like the other environmental problems، is assuming serious dimensions in Delhi. From the last few decades، the study area has been experiencing a significant increase in the generation of solid waste that is adversely affecting its physical environment and is creating aesthetic problems. The current study reviews the data on the quantity of municipal solid waste generation، its physico-chemical characteristics، collection and disposal system. During the analysis it has been found that rapid populationgrowth in Delhi has enhanced the rate of generation of solid wastes manifolds. Consequently، the management of waste has become Herculean work، and، piles of garbage and waste of all kinds littered everywhere have become a common site. The present analysis highlighted that the existing system of waste collection and its disposal within the municipal board is not only inadequate and insufficient but also unscientific. It has been tried to develop a strategy for mitigating and managing this problem in the sustainable urban development perspectives by involving Non-Government and Community-Based Organizations. Besides، the analysis also provides a background for the discussion of strategic issues relating to how these organizations in Delhi can assist the local government in solving the waste management crisis.

The solutions of mathematical models for the estimation of the kinetic, and biokinetic parameters of naphthalene, anthracene and pyrene during degradation in surface and subsurface soils are presented in this work. The models were developed using the twin concepts of rate-determining step and steady-stateapproximation method. They described the biodegradation of single and a mixture of polycyclic aromatic hydrocarbons. Prediction of the concentration of the reactive PAHs with time was aided by fitting the models to the experimental data obtained from a soil microcosm reactor. Given an initial concentration of 100mg/L, approximately 2.9%, 1.9% and 1.4% of naphthalene, pyrene and anthracene present in the microcosm reactor at zero time were found to be utilized in a minute when the velocity of the reaction remained constant for the period.The rate-determining step model gave a better fit as its reaction rate constant (k) closely fitted the experimental values. Prediction by the steady state approximation model was not feasible as a comparative analysis of both single and multisubstrate results showed that the steady state approximation overestimates the biodegradation rates.Using the relative error method, results indicated that the rate-determining step model showed a deviation of 7.5%. The rate-determining step model was chosen because the differences in the model fits were small and its prediction of mixture experiment was more enhanced.

In the present study, Hydrilla verticillata biomass was investigated as a novel biosorbent for the uptake of basic dye malachite green from its aqueous solution. Kinetic and equilibrium studies were carried out in batch process. Batch adsorption experiments were conducted to study the effect of pH, temperature, sorbent dosage, initial dye concentration, and contact time for the removal malachite green dye. The dye uptake was maximum for the initial pH of 8, temperature of 30oC, sorbent dosage of 0.55g, initial dye concentration 200mg/l and contact time – 150 min. The kinetic studies were well modeled using pseudo first order and second order with isotherm studies.

In order to optimize sludge depth in sand drying beds under the climatic conditions of Saudi Arabia, the effect of initial sludge depth on the fate of pathogens was investigated.The investigation was carried out for one year in Al-Khobar Wastewater Treatment Plant, where initial sludge depths of 10, 15, 20, 25, 30 and 35 cm were implemented. Sludge samples were collected on 0, 1, 2, 4, 7, 14, and 30 days and were analyzed for various types of bacterial species and protozoan and helminthic pathogens.The study showed that the effect of the initial sludge depth in drying beds on the dye-off rate of pathogens under investigation was apparent.Total coliform, streptococci, shigella, salmonella and clostridium were found tosurvive longer as the sludge initial depth was increased. As an example, the streptococci count reached values of 25, 37, 49, 59, 71, and 90 organisms per gram dry weight for sludge initial depths of 10, 15, 20, 25, 30 and 35 cm, respectively.The same trend was also observed for protozoan and helminthic pathogens. For example, the number of ascaris lumbricoides after 2 days of drying was 3, 4, 6, 7, 7, and 10 in sludge samples collected from drying beds with initial depths of 10, 15, 20, 25, 30 and 35 cm, respectively.A mathematical representation was formed to describe the pathogens dye-off with respect to time that included the effect of the sludge initial depth. The results indicated that the mathematical representation of the drying beds for individual species was dramatically improved when average values of constants for individual species were used in the model.

Coastal lagoons are complex ecosystems exhibiting a high degree of non-linearity in the distribution and exchange of nutrients dissolved in the water column due to their spatio-temporal characteristics. This factor has a direct influence on the concentrations of chlorophyll-a, an indicator of the primary productivity in the water bodies as lakes and lagoons. Moreover the seasonal variability in the characteristics of large-scale basins further contributes to the uncertainties in the data on the physico-chemical and biological characteristics of the lagoons. Considering the above, modelling the distributions of the nutrients with respect to the chlorophyll-concentrations, hence requires an effective approach which will appropriately account for the non-linearity of the ecosystem as well as the uncertainties in the available data. In the present investigation, fuzzy logic was used to develop a new model of the primary production for Pulicat lagoon, Southeast coast of India. Multiple regression analysis revealed that the concentrations of chlorophyll-a in the lagoon was highly influenced by the dissolved concentrations of nitrate, nitrites and phosphorous to different extents over different seasons and years. A high degree of agreement was obtained between the actual field values and those predicted by the new fuzzy model (d = 0.881 to 0.788) for the years 2005 and 2006, illustrating the efficiency of the model in predicting the values of chlorophyll-a in the lagoon.

Phenol and its homologues are aromatics containing hydroxyl, methyl, amide and sulphonic groups attached to the benzene ring. These molecules are both anthropogenic and xenobiotics. Phenols are environmental pollutants discharged through wastewaters from various industries. Phenols are toxic to several biochemical reactions. However biological transformation of phenols to non-toxic entities exists in specialized microbes, owing to enzymatic potential involving enzymes of aromatic catabolic pathways. In this study, a series of experiments were performed to examine the effects of the mineral medium composition and the pH on phenol removal. In this purpose, phenol biodegradation was carried out in a batch reactor containing mixed bacteria; the temperature (30°C), the stirring velocity (200 r /min) and the phenol concentration (125 mg/L) were kept constants. The initial pH was varied in the range 5 – 9 and the mineral components were tested in the following concentration ranges: 0 – 2 g/L for NH4Cl, 0 – 4 g/L for KH2PO4, 0 – 4 g/L for NaH2PO4 and 0 – 0.2 g/L for MgSO4. Their effects on phenol biodegradation and specific growth rate were examined. All experiments were carried out at a given initial bacterial concentration of 0.08 g/L (based on optical density determination, 0.079). The shorter biodegradation time of phenol was 20.6 h for NaH2PO4, KH2PO4 and MgSO4 concentrations of 2 – 4, 3 and 0.2 g/L respectively. Maximum specific growth rate (0.65 h-1) and total phenol removal (99.99 %) were recorded for an optimal pH value of 8 and the following mineral medium concentrations (g/L): 1, 4, 3 and 0.1 for NH4Cl, KH2PO4, NaH2PO4 and MgSO4 respectively.

Phenol is a common pollutant that was listed by US Environmental Protection Agency (EPA) among the priority pollutants. Classical methods employed for phenol removal are either costly or limited to large-scale applications such as biological and thermal decomposition methods. In this study, adsorption of phenol by a type of clay that is extracted from a local soil called Khoweldi was investigated. The X-Ray diffraction revealed that the studied clay is mainly muscovite. The study showed that the local clay could be used as matrix for long-term storage of organic pollutants. Phenol adsorption isotherms conducted on natural and modified clay with Hexadecyltrimethylammonium (HDTMA) revealed that HDTMA enhanced theadsorption capacity of the clay for phenol.To prevent the migration of the adsorbed pollutants into the environment, encapsulation of the modified clay by organosilane was found to be very effective.

The Gulf of Mannar, located between India and Sri Lanka, is a shallow embayment of the Bay of Bengal. The gulf, which has been declared a bio-reserve is a highly productive area endowed with rich marine fauna including corals. In order to study the origin and nature of the sediments and paleo-environment, 2.6 m length core was collected with 5cm interval at 1320m water depths. Textural studies indicate that the sediments have been poorly sorted and most of the sub samples are silty clay and few top samples are sandy silty clay. The nature of organic matter also indicate high sedimentation rate. Based on the behaviors of CaCO3, Organic matter (OM) and textural parameters the core was studied under the three units. The first unit represents surface to 65cm (unit-1), the second unit (unit-2) represents 65cm to 165cm and third unit represents 165 cm to the bottom of the core. The major oxide geochemistry shows higher concentration of detritus constituents. The trace element studies indicate ferruginous nature for all elements except Cu and Zn. The element/Al ratios also are computed. The geochemical analysis for trace elements like Mn, Cr, Cu, Ni, Co, Pb, and Zn has been carried out for core sediments. Normalization with Al values for all the trace elements have been calculated.

Forty seven sediment cores recovered from the South China Sea coasts along the east coast of Peninsular Malaysia were analysed for As, Cd, Cr, Cu, Hg, Ni, Pb and Zn using instrumental neutron activation analysis. The results indicate a homogeneous distribution except for As and Pb in all stations. Assessment of heavy metal pollution in marine sediments requires knowledge of pre-anthropogenic metal concentrations to act as a reference against which measured values can be compared. Primitive values for the cored sediments were determined from shale average metal. Various methods for calculating metal enrichment and contamination factors are reviewed in detail and a modified and more robust version of the procedure for calculating the degree of contamination is proposed. The revised procedure allows the incorporation of a flexible range of pollutants, including various organic species, and the degree of contamination is expressed as an average ratio rather than an absolute summation number. Comparative data for normalized enrichment factors and the modified degree of contamination show that the South China Sea sediments are in uncontaminated to moderately contaminated level of heavy metal contamination. Compared to obtained values the Kelantan and Pahang big rivers mouth show higher enrichment averaged across other sites.

Since the surface water is one of the main potable water resources, the usage of chlorine as a disinfectant has increased. Consequently the production rate of disinfection by-products (DBPs) such as Trihalomethane (THM) compounds has grown dramatically. In this paper the THMS concentration changes in the Sangar Water Treatment Plant (SWTP) and Rasht Water Distribution System (RWDS) is presented. The duration of these monitoring tasks were 6 months in 2007 and samples were collected every 2 weeks. Water samples were collected from five locations at SWTP and RWDS. Some independent variables including Total Organic Carbon (TOC), pH, temperature, and residual chlorine were measured by Pearson method to find a relation between THMS formation and these variables. In the case of TOC, Pearson method showed a correlation of r = 0.8096 for SWTP and r = 0.3696 for RWDS between THM formation and TOC. Also the relationship for SWTP was r = 0.239 and r = 0.2336 for RWDS between THM formation and temperature. Correlation between THM formation and pH, Pearson method showed r = 0.4658 for SWTP and r = 0.3232 for RWDS. In the case of residual chlorine, Pearson method showed a relationship of r = 0.7354 for SWTP and r = 0.5623 for RWDS. Results proved a direct relation between THMS concentration and distance of chlorination injection points. The results showed that in SWTP, 42.7 percent of THM compounds were removed after sedimentation and filtration.

Methane is one of the important greenhouse gases that contribute to a rise in global mean surface temperature. Aquatic environments are postulated to contribute > 50% of the total global methane (CH4) flux to the atmosphere (de angelis and Lilley, 1987). Dissolved methane concentration in surface waters was measured from January to December 2008 at two selected sites upper reaches (ONGC Bridge) and lower reaches (Dumas) of Tapi estuary, Gulf of Cambay, Gujarat, India. Besides, the important hydrochemical parameters like total organic carbon (TOC), dissolved oxygen (DO), salinity and nutrients (phosphate, nitrate and sulphate) were also analyzed. The mean dissolved CH4 concentration for all water samples at upper reaches was 1369.00 nmol/L and at lower reaches was 1082.04 nmol/L. The positive correlation was found between dissolved methane content and total organic carbon. On the contrary, the negative correlation was observed between methane concentration and nutrients like dissolved oxygen, salinity, phosphate, nitrate and sulphate. The probable causes for varying dissolved methane concentration and saturation at different reaches with hydrochemical parameters are discussed.

The main problem of solid waste management system in Tehran is to handle a large amount of waste (7.641 ton/day in 2008). Therefore, source reduction can be introduced as one of the first priority for solid waste management in Tehran. This research represents the first attempt to quantify the source reduction potential in the city, and subsequently, outlines the principle guidelines, legislations and strategies regarding source reduction application in Tehran metropolitan area. Based on the findings of current research source reduction strategies can be implemented in dealing with packaging material, paper, street waste, mixed household waste and hazardous household wastes. Also industrial wastes produced inside city boundaries can be reduced drastically by implementing source reduction measures. It is also found that any recycling program can be combined effectively with source reduction strategies. The waste reduction potential for each component of waste stream is calculated as the result of the research source reduction potential were determined as: horticultural waste, 80%; food waste, 80; paper and cardboard, 50%; textiles, 20%; metals including ferrous and nonferrous, % 90; Glass, % 30; PET%, 70, and plastic 80%.Finally, overall potential for source reduction in Tehran city is estimated to be 66% for the waste stream as a whole.