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1.
A combined mathematical geophysical model for prediction of pyrite oxidation and pollutant leaching associated with a coal washing waste dump 总被引：3，自引：0，他引：3
F. Doulati Ardejani Ph.D. B. Jodieri Shokri M.Sc. A. Moradzadeh Ph.D. E. Soleimani Ph.D. M. Ansari Jafari Ph.D. 《International Journal of Environmental Science and Technology》2008,5(4):517-526
The waste produced by coal washing process produces many environmental problems. In this study, the pollution problems associated with the waste produced by Alborz Sharghi Coal Washing Plant was investigated by mathematical modeling. The study area is located at 11 km. to Razmjah coal region and 45 km. to Tehran-Mashhad road in the north part od Iran. To achieve the goal, a few samples were taken from different depths at three points on the waste dump in order to investigate pyrite oxidation and pollution generation. The samples were then analysed, using an AA-670 Shimadzu atomic absorption to determine the fraction of pyrite remained within the waste particles. A numerical finite volume model using Phoenics package has been developed to simulate pyrite oxidation and pollution generation from the Alborz Sharghi coal washing waste dump. The pyrite oxidation reaction is described by the shrinking-core model. Gaseous diffusion is the main mechanism for the transport of oxygen through the waste. The results of numerical modelling were compared with the field observations and close agreement was achieved. A simple mathematical model incorporating advection and hydrodynamic dispersion processes was also presented in order to verify the results of geophysical time-laps method showing transportation of the pollutants through the downstream of the waste dump. Both mathematical model and geophysical time-laps method are agreed in the identification of pollutant transport emanated from the waste dump. The results of such investigations can be used for designing an effective environmental management program. 相似文献
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Effects of biochar and bio-fertilizer on yield and qualitative properties of soybean and some chemical properties of soil 总被引：1，自引：0，他引：1
Zahra Arabi Hasan Eghtedaey Bahman Gharehchmaghloo Abolfazl Faraji 《Arabian Journal of Geosciences》2018,11(21):672
This study attempted to examine the effects of biochar amendment together with bio-fertilizer on soybean yield and its qualitative properties, as well as a few chemical properties of soil through a factorial randomized complete block design at three replications in east of Golestan Province (Iran) during 2014. The two factors under study included the following: (1) biochar amendment (in four levels of 0, 2.5, 8, and 16 tons per hectare), (2) bio-fertilizer containing phosphorus and sulfur growth-promoting rhizobacteria (in two levels of inoculation and non-inoculation) applied through foliar feeding. The results of analysis of variance indicated that interactions of biochar amendment and bio-fertilizer on harvest index and grain yield were significant (p ≤?0.01). According to the results of this study, the highest harvest index and oil content were 56.9, and 17.7%, respectively, in the treatment of 8 tons per hectare biochar and inoculation with bio-fertilizer. The lowest harvest index and the lowest oil content were in the control treatment. The interaction of biochar and bio-fertilizer on bulk density and cation exchange capacity was significant (p ≤?0.01). The results of this study demonstrated that biochar affected the amount of residual nitrogen in the soil after harvest, cation exchange capacity (CEC), acidity (pH), and electrical conductivity (EC). The highest grain yield (3440 kg/ha) was in the 8-ton biochar treatment with inoculated bio-fertilizer. Our study concludes that the biochar and bio-fertilizers can improve grain yield of soybean till 51% relative to the control. 相似文献
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Mahnaz Parvaneh-Nejad SHIRAZI Mohammad BAHRAMI Bahman REZAEE Shahin GHARAMANI 《《地质学报》英文版》2011,85(4):777-783
The middle Cretaceous Kazhdumi Formation,with a thickness of 222 m,belongs to the Bangestan Group and occurs in the Zagros folded zone in southwest Iran.The lower boundary with the Dariyan Formation is disconformable,which is recognized by iron oxides and glauconite.The recognized microfossils are Valvulammina sp.,Scandonea sp.,Daxia cenomana,Choffatela sp., Pseudolituonella reicheli and calcareous algae-Lithocodium aggregation(which belongs to the Sarvak Formation),representing the beginning of Cenomani... 相似文献
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Mehrdad Soleimani Behshad Jodeiri Shokri Mehrnoush Rafiei 《Natural Resources Research》2017,26(1):75-88
Introducing and applying an appropriate strategy for reservoir modeling in strongly heterogeneous and fractured reservoirs is a controversial issue in reservoir engineering. Various integration approaches have been introduced to combine different sources of information and model building techniques to handle heterogeneity in geological complex reservoir. However, most of these integration approaches in several studies fail on modeling strongly fractured limestone reservoir rocks of the Zagros belt in southwest Iran. In this study, we introduced a new strategy for appropriate modeling of a production formation fractured rock. Firstly, different rock types in the study area were identified based on well log data. Then, the Sarvak Formation was divided into nine zones, and the thinner subzones were used for further fine modeling procedure. These subzones were separated based on different fracture types and fracture distribution in each zone. This strategy provided sophisticated distribution of petrophysical parameters throughout the grids of the model, and therefore, it can handle strong heterogeneity of the complex reservoir. Afterward, petrophysical parameters were used to produce an up-scaled 3D gridded petrophysical model. Subsequently, maps of petrophysical properties were derived for each zone of the Sarvak Formation. Evidences achieved in this study indicates Sarvak Formation zone 2 as the target production zone with better performance of reservoir rock and the southwestern part of the field as area of maximum porosity. 相似文献
6.
F. Doulati Ardejani B. Jodeiri Shokri M. Bagheri E. Soleimani 《Environmental Earth Sciences》2010,61(8):1547-1560
Acid mine drainage (AMD) pollution is considered to be the most serious water pollution problem in mining areas. AMD containing
iron sulfates and other components can affect the receiving water bodies. Pyrite oxidation and AMD generation can be considered
as important processes that may take place in the wastes produced by coal mining and coal washing operations in the Golestan
province (northeast Iran). The study area is characterized by appropriate atmospheric conditions that favor pyrite oxidation
and the presence of a large amount of water bodies. This study attempts to consider pyrite oxidation and AMD generation in
the Azad shahr–Ramian region. The impact of AMD on the quality of the surface water bodies was investigated by taking samples
and analyzing them for hydro-geochemical parameters. Stiff and Piper diagrams were used to represent chemical analyses of
water samples. The coal samples taken from different depths at four points on two different coal waste dumps were analyzed
to find the fraction of pyrite that remained in the waste particles to investigate the pyrite oxidation process. A computational
fluid dynamic package called PHOENICS was used to model pyrite oxidation process numerically. The results obtained from the
geochemical analyses of water and coal samples and numerical simulation show pyrite oxidation and acid generation in the region.
However, the presence of carbonate rocks raised the pH of the water samples. The drainages of the Razi mine may be recognized
as natural alkaline mine drainages. 相似文献
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Sadeq Dezhkam Bahman Jabbarian Amiri Ali Asghar Darvishsefat Yousef Sakieh 《GeoJournal》2014,79(5):591-604
Urban growth models (UGM) as regional planning tools are of great interest for quantitative analysis of urban complex systems. In this study, the SLEUTH UGM has been calibrated through a sequential multistage automated method to derive the pattern of urban growth in Rasht County from 1975 up to year 2011. Evaluation of model goodness of fit confirms that the model is adjusted properly to the area under investigation. Four growth rules of spontaneous, new spreading center, edge and road influenced growth as well as five coefficients of diffusion, breed, spread, road gravity and slope resistance are responsible to detect quantitative aspects of urban dynamics from control years. According to the results, successive improvement of the model parameters during the calibration mode indicates applicability of the model for forecasting of future urban growth mechanism until the year 2050. Accordingly, two growth scenarios were developed mainly with the aim of investigating the coefficients’ role in controlling the nature of urban dynamics. In this concern, the spread and road gravity coefficients’ value, as two major driving forces of urban sprawl in the study area were reduced to dictate compact and infill growth, compared to their original values derived from calibration for historical prediction. Comparison between two forecasted scenarios indicates insignificant difference in total amount of the urban area, which denotes there is a threshold to urbanization and the current trend of urban growth could not be maintained. Finally, we conclude that Rasht County with considerable industrial and agricultural attractions, will witness noticeable expansion from 20,310 ha in 2011, up to 34,745 ha in 2050, accounting to 71 % increase in total area of manmade surfaces. 相似文献
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An optical chemical sensor (optode) is proposed for the kinetic determination of nitrite ion. The optode was fabricated by the immobilization of methyl violet on a triacetylcellulose polymeric membrane. Methyl violet is covalently bonded to a transparent triacetylcellulose film. By immersion of the sensor into an acidic nitrite solution, the absorbance of the sensor at 596 nm decreases with time that is due to the reaction of nitrite with the immobilized methyl violet. A fixed time method of 15 min was used to monitor the reaction. The linear range for the determination of nitrite was 0.20–8.00 µg mL?1 and the limit of detection was 0.08 µg mL?1. The optodes were one‐shot, they had durability more than 2 months and were easily prepared. The optode was successfully applied to the determination of nitrite ion in spring water and sewage samples. 相似文献
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Iran sits on a region with a high intrinsic level of seismic activity due to its tectonic setting. Through statistical examination of the earthquakes listed in the catalogue from International Institute of Earthquake Engineering and Seismology (IIEES), this research attempted to calculate some seismicity factors and find correlation between them. A preliminary analysis indicated changes in the b-value of the Gutenberg-Richter relationship over the study region. Thus, the study area was divided into five zones (Alborz, Zagros, Azerbaijan, Central and East) and b-value was computed for each zone. Considering faulting mechanism styles and the b-values in the region, it was found that the lowest b-values belong to the thrust events and strike-slip faulting earthquakes have intermediate values. These findings support previous studies. Furthermore, results of b-value calculation were used for the estimation of accumulated differential stresses (σ1–σ2) over each zone. Overall, the b-value for Iran is averagely low which signifies the high stress tectonic regime in this region. Also, by having calculated fractal dimension (D) in each zone, a correlation obtained showing that in Iran region, the b-value correlates to fractal dimension by D = 4.2b–2 relation which does not support Aki's (1981) speculation of D = 3b/c. 相似文献