Environmental Science
A.R. Karbassi; S. Tajziehchi; H. Khoshgalb
Abstract
Fuel storage tanks are one of the main sources of water pollution as well as loss of crude oil and oil products in refineries. In the process of utilization of these tanks, considerable amounts of hydrocarbons may find their way into the coastal water, which eventually lead to loss of valuable ...
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Fuel storage tanks are one of the main sources of water pollution as well as loss of crude oil and oil products in refineries. In the process of utilization of these tanks, considerable amounts of hydrocarbons may find their way into the coastal water, which eventually lead to loss of valuable hydrocarbons. Oil type, climatic condition and characteristics of oil tanks are among the main variables in computing evaporative losses. The present study brings out the results of a project that was carried out to investigate the adverse effects of oil terminal on coastal waters of Qeshm Island and aims to elaborate on speciation of metals in coastal waters. For this purpose, 12 stations were sampled. Water chemistry software was used to draw Eh-pH diagrams. Along with the speciation of heavy metals, cluster analysis was carried out by MVSP software. According to the results, HSC diagrams showed that Cu and Cd were present as free ions. Lead, manganese, cobalt, zinc and nickel were respectively present as PbOH, MnOH, ZnOH, CoOH and NiOH in the Persian Gulf. Speciation of Cu and Ni was in the form of Cu2O and NiO. Vanadium was also present in combination with hydroxide. Since all the studied elements were within the water stability range, they were stable, and there were no environmental risks of contamination and toxicity. The results of cluster analysis did not show any relation between Eh and pH. This clearly showed that Eh-pH was governed by different mechanisms in coastal waters of Qeshm Island. Vanadium and Ni concentration was governed by pH, while Cu and Cd concentration was controlled by Eh.
L. Askarizadeh; A.R. Karbassi; M.B. Ghalibaf; J. Nouri
Abstract
Ancient City of Ray, located at the southern urban part of Tehran province, is one of the best recognized civilization sites in the world. In this study, the past earthquake incidence in Ray was reviewed using hazards united states tool as a geographic information system-based natural hazard analysis ...
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Ancient City of Ray, located at the southern urban part of Tehran province, is one of the best recognized civilization sites in the world. In this study, the past earthquake incidence in Ray was reviewed using hazards united states tool as a geographic information system-based natural hazard analysis tool. hazards united states tool was chosen to estimate the damage on structural and non-structural elements during various earthquake scenarios with magnitudes of 4.5, 6 and 7.5 on the Richter scale in Ray City. Earthquake magnetitudes of 4.5, 6 and 7.5 would severely damage 49, 72 and 82% of buildings, respectively. The number of casualties was estimated to be in the range of 558 to 2220 people. It was also computed that 93, 197 and 331 km3 of debris would be produced at 4.5, 6 and 7.5 Richter earthquake, respectively. Subsequently, Arc-GIS was used to find out the best route from the affected areas to the temporary disposal locations and to allocate the required number of heavy equipments and manpowers for debris disposal planning. A set of factors, including diversity of the existing wastes, separation of the recyclable wastes, and allocation of the best place and route for debris disposal in the shortest time and with the shortest distance in the street network, were presented and considered in the analyses. Finally, it was concluded that debris management is not only a logistic activity, but also it is an inseparable part of the post-accident recovery process.
Environmental Science
S. Hassani; A.R. Karbassi; M. Ardestani
Abstract
The flocculation of dissolved heavy metals is a process which has an important effect on decreasing the concentration of the colloidal elements during estuarine mixing of river water and sea or ocean water. During this important process, a large amount of colloidal elements change into particles in ...
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The flocculation of dissolved heavy metals is a process which has an important effect on decreasing the concentration of the colloidal elements during estuarine mixing of river water and sea or ocean water. During this important process, a large amount of colloidal elements change into particles in the form of flock and the dissolved loads decline. This study is performed to evaluate the mechanism of self-purification of heavy metals in Sardabroud's estuary. For this purpose, the effect of salinity (varying from 1 to 8.5‰) on the removal efficiency of colloidal metals (copper, zinc, lead, nickel and magnesium) by flocculation process during mixing of Sardabroud River water and the Caspian Sea water was explored. The flocculation rate of Ni (25%) > Zn (18.59%) > Cu (16.67%) > Mn(5.83%) > Pb(4.86%) indicates that lead and manganese have relatively conservative behavior but nickel, zinc and copper have non-conservative behavior during Sardabroud River’s estuarine mixing. The highest removal efficiencies were obtained between salinities of 1 to 2.5%. Due to flocculation process, annual discharge of dissolved zinc, copper, lead, manganese and nickel release into the Caspian Sea via Sardabroud River would reduce from 44.30 to 36.06 ton/yr, 3.41 to 2.84 ton/yr, 10.22 to 9.7 ton/yr, 8.52 to 7.8 ton/yr and 3.41 to 2.56 ton/yr, respectively. Statistical analysis shows that the flocculation rate of Nickel is highly controlled by redox potential and dissolved oxygen. Moreover, it is found that total dissolved solid, salinity, electrical conductivity and potential of hydrogen do not have a significant influence in flocculation of studied metals.
M.J. Mohammadizadeh; A.R. Karbassi; Gh.R. Nabi Bidhendi; M. Abbaspour
Abstract
The aim of this study is to evaluate the obstacles due to a DPSIR model combined with fuzzy analytic hierarchy process technique. Hence, to prioritize the responses regarding the driving forces, pressures, states and impacts, the hierarchy of the model is established. Evaluations and prioritization of ...
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The aim of this study is to evaluate the obstacles due to a DPSIR model combined with fuzzy analytic hierarchy process technique. Hence, to prioritize the responses regarding the driving forces, pressures, states and impacts, the hierarchy of the model is established. Evaluations and prioritization of model results of urban transport situation in Tehran have provided a number of necessary issues for strategic planning to reduce local air pollution and emission of greenhouse gases by prioritizing their effectiveness in the implementation, including; a) development and improvement of public transport (R1), b) improvement of fuel quality (R2), c) improvement of vehicle emission standards (R3), d) vehicle inspection (R4), f) traffic management (R5). In this study, responses to improve the factors of pressure, stimulus, the current state and the impacts were examined and compared hierarchically. Finally, their priority relative to each other was achieved. Development and improvement of public transport, improvement of the quality of fuel, improvement of vehicle emission standards, vehicle check-up and finally urban traffic management were identified respectively as practical steps to control and reduce air pollution in Tehran.
Gh. A. Mohammadpour; A.R. Karbassi; A. Baghvand
Abstract
Presence of toxic metals in agricultural soils can impose adverse health impact on consumers. The main purpose of this study was to determine spatial distribution of elements Fe, Sb, Mn in agriculture soils and crops of Hamedan Province in Iran. Soil samples (0-20 cm depth) were collected from an ...
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Presence of toxic metals in agricultural soils can impose adverse health impact on consumers. The main purpose of this study was to determine spatial distribution of elements Fe, Sb, Mn in agriculture soils and crops of Hamedan Province in Iran. Soil samples (0-20 cm depth) were collected from an area of 2831 km2. Iron, Antimony and Manganese in samples of soil and agricultural crops were extracted and their amount was determined using atomic absorption spectrometer. The spatial distribution map of the studied elements was developed using Kriging method. The main concentration of Fe, Sb and Mn in the soil of the study area is about 3.8%, 2.5 and 403 mg/kg, respectively. According to chemical partitioning studies, the anthropogenic share of Fe, Sb and Mn is about 28.51%, 34.83% and 30.35%, respectively. Results of comparison of heavy metals pollution intensity in the agricultural soil with geo-accumulation index and also pollution index, illustrated that iron and manganese are classified in the Non-polluted class and antimony is in the moderately polluted class. Analysis of zoning map of pollution index showed that Fe, Sb and Mn are of geological sources. In fact, these metals are naturally found in soil. However, anthropogenic activities have led to more accumulation of these metals in the soil. The obtained health risk for metals in agricultural crops is indicative of safe value for consumers.
Environmental Science
A.R. Karbassi; S. Tajziehchi; N. Farhang Adib
Abstract
Estuaries are well known for their potential in removing metal from fresh water to provide micro-nutrients to aquatic life. In the present investigation, we have tried to bring out the metal removal potential of estuaries during accidental spills. For this purpose artificial river water containing high ...
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Estuaries are well known for their potential in removing metal from fresh water to provide micro-nutrients to aquatic life. In the present investigation, we have tried to bring out the metal removal potential of estuaries during accidental spills. For this purpose artificial river water containing high concentration of Mn, Cu, Zn, Ni and Pb were mixed with sea water at different salinity regimes. Water samples were taken from a station on the main branch of Tajan River that flows in to the Caspian Sea. For this purpose, solutions with a concentration of 5 mg/L of each studied metal (Mn,Cu, Zn, Pb) were prepared in Tajan River water. The salinity regimes include 3, 6, 8, 10 and 11 ppt. It was noted that metal concentration decreased by increasing salinity. Metals were flocculated at different rates: Cu (88%) > Ni (86%) > Pb (84%) > Mn (74%).Thus, as average about 80% of total elemental content flocculates. Hence, it was concluded that a large amount of micro nutrients is carried by the river and flocculated in the estuary where the river water mixes with the sea water which may play a vital role in supplying nutrients to the aquatic animals. Cluster analyses have shown that Mn and Ni are governed by EC, pH and salinity.
A.R. Karbassi; S. Tajziehchi; S. Afshar
Abstract
Oil and pollutants resulting from its extraction and exploitation are considered as one of the serious problems for human health. Vast oil fields of Ahvaz City located in southern Iran are known as one of controversial subjects in contamination with heavy metals. In this study, oil fields' soils of Ahvaz ...
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Oil and pollutants resulting from its extraction and exploitation are considered as one of the serious problems for human health. Vast oil fields of Ahvaz City located in southern Iran are known as one of controversial subjects in contamination with heavy metals. In this study, oil fields' soils of Ahvaz city (Ab-Teymour) were chemically analyzed in order to determine the concentration of eight heavy elements (Cu, Ni, V, Co, Cd, Zn, Mo and Pb) and intensity of contamination. The area was divided into 12 plots with respect to proximity to drilled oil wells as well as the existing flares. The results show that concentration of studied metals is higher than earth’s crust mean values. According to Muller’s geochemical index, intensity of contamination varies from unpolluted to highly polluted ones. These highly polluted areas require methods such as phytoremediation more than ever. By comparing list of local plants with that of heavy metals absorbing plants and given the local climate, a suitable absorbing plant for each of the existing heavy metals was recommended.
A.R. Karbassi; M. Pazoki
Abstract
In this study, the concentrations of heavy metals (Ca, Zn, Cu, Fe, Mn, Ni) in thesediment of Shavoor River in Khuzestan Province in Iran has been investigated. After the library studies and field studies, six samples of water and sediment were taken from the river in order to evaluate heavy metal pollution ...
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In this study, the concentrations of heavy metals (Ca, Zn, Cu, Fe, Mn, Ni) in thesediment of Shavoor River in Khuzestan Province in Iran has been investigated. After the library studies and field studies, six samples of water and sediment were taken from the river in order to evaluate heavy metal pollution in sediments. To determine the geochemical phases of metals in sediment samples the 5-step method was used for chemical separation. For quantitative assessment of the severity of contamination in the sediments, the geochemical indicators such as enriched factor (EF) and the accumulation index (Igeo) were used. Also, the statistical analyses including methods such as correlation analysis cluster analysis the (CA), were conducted.The results of the experiments showed that the organic matter deposited varies with the average of 2.49 and ranges between 1.95% and 3.43%. Samples showed concentrations of metals such as calcium, iron, manganese, copper and nickel at all the sampling points were below the global average, whereas the concentration of copper was slightly higher than the global scale. Enriched factor (EF) was calculated for the elements revealed that heavy metals are classified as non-infected. The Geo-accumulation Index showed that the studied elements were uninfected peers. Based on the results of multivariate statistical analysis it was concluded that metals such as manganese, copper, iron, nickel and zinc are mainly natural and calcium metal is likely to have an organic origin.
A.R. Karbassi; M. Heidari
Abstract
One of the most paramount processes that play a considerable role in reducing the concentration of heavy metals during estuarine mixing is flocculation. Not only does such a process cause a huge percentage of metals to come into the particulate phase, but also it provides ample nutrients for the aquatic ...
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One of the most paramount processes that play a considerable role in reducing the concentration of heavy metals during estuarine mixing is flocculation. Not only does such a process cause a huge percentage of metals to come into the particulate phase, but also it provides ample nutrients for the aquatic life. In the present study, impact of such factors as salinity, pH and DO on flocculation of Cu, Zn, Pb, Ni, Cd and Mn throughout mixing of Chaluse River with Caspian Sea is investigated. The trend of flocculation of Pb (24.32%) < Zn (24.38%) < Cd (40.00%) < Cu (64.71%) < Ni (68.00%) < Mn (76.47%) reveals that among the studied elements Mn and lead experience minimum and maximum flocculation at diverse salinity regimes, respectively. Moreover, flocculation rate of studied metals fluctuates between 24.32 and 76.47 percent. It is interesting to note that much of metal flocculation occurs at the very lower (less than 2 ppt) salinity regimes.
