JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY
Year:2018 | Volume:20 | Issue:2 (77) |Papers Count:20

Background and objective: Petrochemical industry as well as some other industries is one of the environmental pollution which polluttted wastewater with ammonia nitrogen. The objective of this study was two-step ammonia nitrogen removal from Kermanshah Petrochemical effluent using native bacteria immobilized on granular activated carbon. Method: This study conducted in continuous mode using two reactors with effective volume of 1. 7 l for each reactor. These reactors operated as up-flow and fixed film. Granular activated carbon immobilized with nitrifier and denitrifire bacteria has been used as media. Initial concentrations of ammonia and nitrate (50-200 mg/l) with retention time (1-3 h) at pH 8 and temperature of 28 ± 3 ° C were studied. Findings: Results showed that with increasing in retention time in both reactors nitrification and denitrification efficiency increased. The maximum nitrification and denitrification rates were 2. 69 Kg NH4+/m3. d and 2. 49 Kg NO3-/m3. d respectively. Maximum nitrification and denitrification rates occurred at 3h retention time and ammonia and nitrate removal efficiency were achieved 99. 5 percent. Discossion and Conclusion: This study has been showed that native bacteria immobilized on granular activated carbon and use of that in a continuous up-flow attached-growth reactor for the removal of ammonia has a high efficiency.

Background and Objective: Contamination by polycyclic aromatic hydrocarbons is one of the most common cases in oil-rich province of Khuzestan. The main purpose of this study was to determine the amount of polycyclic aromatic hydrocarbons in soil of Haft Shahidan Dissalination and Operating Factory which is Located in Masjed Soleyman. The soil were sampled from seven stations in two seasons of winter and spring in 2015. Method: The soil samples were homogenized after they are collected and transported to the laboratory. After extraction, 16 compositions were measured by means of GC-MS. Furthermore, the amounts of pH, EC, organic matter and aggregation available in soils were measured. Findings: The results showed the mean PAHs in soil collected from stations 1 to 7 were respectively 265081, 55. 78, 31. 04, 46. 33, 62. 61, 33. 70, and ND mg/kg dried-form weight in winter and 310. 82, 63. 69, 38. 12, 55. 36, 77. 14, 44. 62, and ND mg/kg dried-form weight in spring. There was a negative correlation among the amount of PAHs available in soils, the amounts of EC parameters and pH deposits in 0. 01 and a positive correlation with organic matter. Discussion and Counclusion: The results collected from the ratio of the molecular showed that all the stations contain a mixture of Payerolitic and Pethrogenic hydrocarbons. The results show that stations 1, 2, 5, and 6 have high level of PAHs concentration, which is due to close distance of these stations to the oil tanks and facilities as well as oil leakage. According to the results obtained from all stations, the levels of compounds such as benzo(b)fluorantene, benzo(k)fluorantene, Dibenzo(ah)antheracene and Phenanthrene were found to be higher than the standard of Canada.

Background and Objective: Water recycling is one of the effective ways for overcoming the water crisis. The various methods and techniques for the design of water allocation systems have been developed and used water in industry reduced to an acceptable level. Method: Water pinch technology is a systematic technique for analyzing water networks and reducing related costs. Also this technique is used for minimizing costs, establishing the relationship between operating costs and capital costs inside the compliance with standards of environment. Water Pinch is optimization method to determine targets technique also appropriate changes to suggest the design of network with the possibility to maximize the reuse of water regeneration, reuse / recycle. Findings: In this paper simulation and optimization of oil refinery water network using the software Aspen Water and a graphical-mathematical method Composite Table Algorithm (CTA) has been used for a dramatic reduction in water consumption and waste water refinery which comes to a distribution network. Therefore Extended Composite Table Algorithm is presented to model regeneration-reuse/recycle. Discussion and Conclusion: using Composite Table Algorithm is presented better results to minimize flow rate of fresh water, waste water and costs of fresh water supply and discharge comparison with Aspen water. Then the Extended Composite Table Algorithm method is obtained highly successful results in optimization water network by applying regeneration unit inside reuse/recycle.

Background and Objective: Recently much attention has been paid to the development of alternative fuels in order to meet the emission standards and to reduce the dependency on fossil fuel. Especially biodiesel and ethanol have been considered as major alternative fuels as they are derived from renewable sources. These fuels are well oxygenated and therefore have a great potential to reduce emissions. Method: This study is aimed at investigating the effect of operating factors of engine load and speed as well as blended levels of biodiesel and ethanol in diesel fuel on the specific fuel consumption of a DI diesel engine OM 314. The experiments were designed using a statistical tool known as response surface methodology (RSM). Findings: The results depicted that specific fuel consumption increased with increasing percentage of bioethanol and biodiesel and the minimum of the specific fuel consumption (156 g/kWh) was accured at full load and engine rotational speed of 2453 rpm for pure diesel (B0E0D100) Discussion and Conclusion: the maximum of specific fuel consumption was obtained with amount of 413 g/kWh at 20% engine load and rotational speed of 2800 rpm and for a fuel blend containing 0. 4 l biodiesel, 0. 4 l ethanol and 1l diesel (B22E22D56).

Background and Objective: Today environmental pollutions especially pollution of water ecosystems have caused serious problems for human communities as well as other living organisms. In regards with increasing growth of population using chemicals has increased in different industrial, agricultural and residential sectors. Endocrine disrupting chemicals or strogenic-like compounds are the great importance due to their negative consequences on human beings and animals (fish and amphibious). The aim of this study was determining the concentration of Nonylphenol and Bisphenol A in water samples of estuaries of 9 rivers in south-west coast of Caspian Sea and examining the correlation of these compounds with chemical oxygen demand (COD), biological oxygen demand (BOD) and pH. Method: In this study, different parameters based on standard methods for water and wastewater was measured. To extract Nonylphenol and bisphenol A of water samples was used of liquid-liquid separation method. And Nonylphenol and bisphenol A concentration was measured with high performance liquid chromatography. Findings: Results showed that estuary of Astara River has the biggest concentration of studied parameters compared to other stations which can be due to the passage of river through the city center and penetration of municipal and residential waste water to the river. Result of correlation test indicated that there is a positive and significant correlation between BOD and COD concentrations، and Bisphenol A and Nonylphenol in studied samples. There is also a negative (inverse) and significant correlation between the pH and Bisphenol A and Nonylphenol concentrations. Discussion and Conclusion: Since the presence of these chemicals even in low concentrations can have adverse effects in health of ecosystems. There are concerns regarding the presence of these strogenic-like chemicals in water resources in the country.

Background and Objective: In spite of the numerous studies published on soil-pollutant interaction in recent years, no considerable research has been conducted on the interaction between heavy metal pollutants and nanoclays. Lead is a common heavy metal pollutant in geotechnical and environmental projects. Moreover, although researchers have introduced equations for retention of metal pollutants in soils, no research has been conducted on heavy metal retention capability of nanoclays and the effect of carbonate on equations related to retention capability. Therefore, this study intended to examine the geotechnical-environmental behavior of nanoclays and carbonate-modified nanoclays in terms of capability to adsorb the heavy metal pollutant lead and to propose equations for pollutant retention by nanoclays. Method: To achieve this objective a series of environmental and geotechnical experiments were conducted to analyze the mechanism of retaining the heavy metal pollutant lead by examining pH variations, capability of pollutant retention, and through evaluating X-ray diffraction (XRD). Moreover, a series of linear and non-linear equations was used to study the capability of nanoclay Cloisite Na+ in retaining the heavy metal pollutant lead at various ambient pH values and different carbonate contents of the specimens. Findings: Results showed that carbonate content was an effective factor in pollutant retention and had to be included in the numerical equations. Inclusion of the pH variation parameter in the equations increased the correlation coefficient in the proposed equations. Discussion and Counclusion: The proposed numerical equations can be a proper substitute for laboratory methods, and also can be used in designing landfill sites.

Background and Objective: Environmental pollutions are the side effects of industrial activities which put the environment in danger. On the other hand by growing population and increasing electricity usage in the country, it is necessary to construct new power plants. Power plants were prioritized based on different criteria. In this research based on the environmental, social and economical aspects Kahak wind powerplant (the biggest wind powerplant) and Pakdasht Combined cycle powerplant (the biggest combined cycle powerplant in Iran) were studied. Method: In this research, Multi criteria decision making methods such as AHP and Topsis were used to select the priority of the power plants. These two methods are the most important and optimal decision making methods. Findings: Among the five environmental criteria which were chosen by experts water (weight of 0. 451) was placed in the first rank. Other criteria like weather (weight of 0. 223), social and economical effects (weight of 0. 120), soil (weight of 0. 114) and other environmental effects (weight of. 081) were placed in second to fifth rank. Discussion & Conclusion: As a result because of less environmental pollution and degredation and also moving towards environmental sustainability based on the expert’ s opinion (Delphis` panel) construction of more suitable powerplants as Wind cycle powerplants are more suitable than combined cycle.

Background and Objective: phosphorus considered among the major pollutants in water environments. Phosphoris contamination in surface water and groundwater resources originates mainly from the excessive use of fertilizers and uncontrolled land discharges of untreated wastewater. Discharge of it into the enviroment causes many negative health impact. The aim of this study was to investigate the efficiency of Fenton’ s advanced oxidation process (H2O2/Fe+2) in the phosphorus removal from aqueous solutions. Method: This is an experimental study which is carried out in laboratory scale. In this study, the effect of the important operational variables including pH, Fe+2 dosage, H2O2 dosage, initial phosphorconcentration, and Contact time were evaluated on the phosphate removal from Aqueous Solution by Fenton has been investigated. Findings: The results showed that this method has the ability to remove phosphorus from aqueous solutions to less than standard level WHO (≤ 1mg/l). pH, ratio H2O2 / Fe+2 and Contact time have direct effect and initial phosphor concentration has reverse effect of phosphor removal. The results showed that the Fenton process, can reach respectively 97% phosphor removal. So that optimum condition of the phosphorus removal is in the Ratio H2O2 / Fe2+ dosage = 2200 /1000 mg/l, contact time of 60 min, pH = 3. 5 in initial phosphor Concentration in 100mg /L. SPSS statistical test showed that the mean concentration in the before and after doing all process, there were significant differences ( P ≤ 0. 05 ). Discussion and Conclusion: Results show, the efficient removal of phosphate using Fenton process is desirable in the water treatment and pollution control. The results of the study is consistent with similar cases by other researchers.

Background and Objective: Water pollution with heavy metals is one of the most important problems of environment. The objectives of this research were to synthesis Manganese dioxide nanoparticles and determining its efficiency in the removal of zinc from aqueous solutions. Method: In order to do this manganese dioxide nanoparticles were synthesized using cathode electrochemical deposition method and the effect of pH, contact time, MnO2 concentration and cadmium concentration on cadmium removal efficiency were investigated in a batch system. Scanning electron microscope (SEM), XRD and FT-IR were used to identify the characterization of synthesized manganese dioxide nanoparticles. Findings: SEM results showed that the diameter of the particles was 30 to 50 nm. The other results showed that the optimum pH value for adsorption was 6. Contact time enhancement and the concentration of absorbent are omitted because they make the efficiency boost. The adsorption capacity increased and the adsorption efficiency slightly increased with increasing concentration of zinc and reducing the concentration adsorbent. Experimental data were shown the best to follow Langmuir model. Langmuir adsorption capacity, was found to be 285/71 mgg− 1. The results also showed that the absorption of zinc was obeyed from pseudo-second-order kinetic model. Discussion and Conclusion: The overall results showed that the use of manganese dioxide nanoparticles was a suitable method with high potential for removal of zinc from aqueous solutions.

Background and Objective: To study the effect of nanostructured silica aerogel as a soil moisture absorbent on yield and water use efficiency of corn and comparison with superabsorbent, a field of experiment was carried out in factorial split plot arrangement using randomized complete block design with four replications at Research Farm of Islamic Azad University, Karaj, Iran, in 2013-2014 growing year. Method: Deficit irrigation with three levels including irrigation with 100, 75 and 50 percent crop water requirement which were located in the main plots and moisture absorbent materials with three levels including non-use absorbent material, used of superabsorbent (30 kg/ha) and used of silica aerogel (5 kg/ha) that were located in the sub plots. Findings: The results showed that the highest grain yield (12684 kg/ha) was achieved in condition of irrigation with 100% crop water requirement and used of silica aerogel. The use of superabsorbent and silica aerogel increased grain yield. While in condition of irrigation with 100% crop water requirement silica aerogel consumption as compared to superabsorbent to increase grain yield was a significant advantage but in condition of irrigation with 75 and 50% crop water requirement silica aerogel and superabsorbent were in a statistical group. The use of superabsorbent and silica aerogel increased water use efficiency for grain yield (116. 2 and 154. 1 percent, respectively) and water use efficiency for biologic yield (38. 4 and 85. 9 percent, respectively) as compared with non-use. Discussion and Conclusion: Therefore, application of nanostructured silica aerogel is recommended for increasing of yield and water use efficiency of corn.

Background and Objectives: The development of industries and attention to environmental issues as well as the sustainable use of all means possible to locate the optimal area of land is one of the important issues in recent years. It has been the focus of environmental management. The present study aims to assess the area and zoning with the appropriate username and petrochemical industries in order to plan and create a regional balance according to the capabilities and environmental conditions suitable to locate the user's industry. Method: In this study the ecological and Non-ecological were the necessary parameters for analysing to weighting these factors using a hierarchical analysis process. Then the nineteenth layer information in the GIS and the methodology the weighted overlay was analyzed. Findings: The results of this study suggest that the north and west, in terms of ecological properties, the ratio has been better and should be the first priority planning. Discussion and Conclusion: Therefore, industrial development, budget and facilities are available at the optimum level can be used to plan for the future development of the industry in these cities. The results show that two AHP and Weighted overlay in the GIS in zoning of industry is capable performance that corresponded with research in other areas.

Background and Objective: The existence of mountains near Tehran has created an opportunity for economic development which is suitable for citizens to spend their leisure time as well. The tourism growth trend in these areas, without taking into account the strategic planning, has led to adverse environmental impacts especially to mountain areas adjacent to Tehran Municipality Region 1 due to uncontrolled utilization. Therefore, the current study aims to assist the management and planning process in area under study Method: This analytical-descriptive study has been carried out in three stages. In the first step the Internal and External Factors Evaluation (IFE and EFE) matrixes were prepared to evaluate the current situation. In the second step, the SWOT (Strengths, Weaknesses, Opportunities and Threats) matrix was developed and accordingly strategies were presented. In the third stage by preparing the Quantitative Strategic Planning Matrix (QSPM), the strategies were evaluated and prioritized Findings: In the IFE matrix the highest weighted score was assigned to “ create a structure named specific mountain area in Tehran Municipality Region 1” , and in the EFE matrix “ low awareness of tourists about importance of mountains” is the highest. Discussion and Conclusion: According to the results 26 strategies extracted. Based on comparison of mentioned strategies “ preparation of the tourism master plan and equipping tourist services in partnership with related organization” is the first step towards strategic management goals in the under studying area and “ maintaining features and distinctive aspects of the valleys of southern slopes of Alborz with the aim of preserving the diversity of tourism products” is the second priority.

Background and Objective: Preserving the natural environment and biodiversity in cities in order to have relation with nature and improve the quality of life according to decreasing quality of the environment and disruption of the ecological foundations, requires integration of ecology knowledge with urban development and planning process. Nowadays, the development of cities resulting from increasing urbanization and migration has been reduced. The purpose of this research is theoretical explanation of new approach to urban ecology and its evolution and roots of shaping urban ecology science. In addition, this article tries to respond to the question that how we can create opportunities to make link between ecological system and natural processes with urban environments and human activities by using urban ecology as a new approach in the process of urban planning and development. Method: This study was conducted by descriptive and analytical methods. It attempted to study the theoretical roots of urban ecology and the way to use it in urban sciences such as urbanization through investigation of samples and its applied applications by doing library studies, analysis of attitudes related to urban ecology and topics related to urban development and planning. Findings: According to the findings of study, urban ecology has proper place as a new approach in today urbanization. So the recovery of urban ecological networks as well as Ecological-based planning and design are considered as practical examples of urban ecology knowledge at local and regional levels. Using this method experts have been able to take steps toward enhance the natural environment and create urban models based on maintaining the ecological values of the cities. Discussion and Conclusion: The results suggest that the use of urban ecology science as a theoretical and practical strategy in planning and designing of cities must be a national priority in order to achieve sustainable and resilient cities. Achieving this goal requires teamwork between various experts, support of interdisciplinary education and changing in the way of establishing the communications between policy and science.

Background and Objective: According to the increasing demand for recreational and entertainment centers, economic and social analysis and investigating human needs providing possibilities and facilities is neccesary. The main objective of this study is to estimate the recreational value of Ahwaz Beach Park as an important entertainment center of Khuzestan people especially Ahwaz city. Method: Individual Travel Cost Method as an effective method in planning and managing development projects was used in this study. Individual visits are as dependent and individual travel cost and socio-economic variables are independent variables. Needed data were collected in 1391 by completing 234 questionnaires from visitors of the site. Findings: The results indicated that the age of visitors has an acceptable but insignificant effect on numbers of visits. On the other hand, the variables of education and income have a positive effect and travel cost has a negative effect on visits. Recreational value of Beach Park was estimated about 157885 Rials per person and 1342022500 Rials for a year in total. Discussion and Conclusion: Since the results indicate the significant economic value of Beach Park, it is necessary to codify its tourism development plan. Policies should be based on development of recreations and urban Parks with maintaining high environmental standards and creating mechanisms for capital return.

Background and purpose: Educational function of the media has always been emphasized by experts in various fields. Formal and informal institutions have used their capacity. In the meantime, the medium of television as a medium of video and audio is important. The aim of this study is to evaluate the effect of environmental programs of television on the promotion of environmental awareness and attitude of university students. Research method: The research method is practical, and the data collection tool isquasi-experimental with pre-test and post-test as well as control group. The studied population consists of 40 students from Payame Noor University, Markazi Province, who are selected by convenience sampling method and randomly classified into two experimental and control groups. The data collection tool includes a questionnaire, the content validity of which is quantitatively and qualitatively confirmed and the reliability is approved by Cronbach's alpha method. The data are analyzed by descriptive and inferential statistics. Findings: According to the results of the statistical analysis, significant differences between pre-test and post-test were observed in both variables. Comparison of the mean pre-test and post-test demonstrated that the mean of the post-test was higherin both variables. The post-hoc test also showed that the mean of the TV experimental group was higher than the mean of control group in both variables. Discussion and conclusion: According to the findings, TV programs have a significantly positive effect on the environmental awareness and attitude of the students especially their environmental awareness which showed a higher extent of effect.