33 research outputs found

    Estudios petrográficos e esotópicos en el área de Kamoo, Noreste de Isfahan, Irán

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    The study area is located 5.5 km north-east of Kamo County and 30 km north-east of Meymeh, Isfahan. Kamo Index comprises an anticline with a northwest-southeast trend, the outcrop of which consists of siltstone-sandstone and Jurassic shale rocks that lie along a cretaceous unit. Based on field studies as well as petrographic and geochemical investigations, mineral assemblages and minerals in the area include chalcopyrite, pyrite, marcasite, and magnetite as primary ores and malachite, bornite, covellite, chalcocite, hematite, goethite, and hydrous iron oxides as secondary ores. The secondary ores have been formed by oxidation and biogenic processes. The primary textures are granular, disseminated, vein-shaped, and layered and the secondary textures are boxed and martitized, shear zones, replacements, and veins. Tectonic, metamorphic, and oxidation factors are involved in the formation of these textures. Due to tectonic activity in this area and the presence of faults, replacement, vein, and shear textures, which have developed after mineralization, are observed. Among alterations, hematite, propylitic, sericitic, limonitic, and kaolinitic are highly prevalent and they are important in the formation of iron deposits. The sub-alkaline granitoids of the region are related to the continental subduction-zone orogenic series. Studies on the decomposed iron samples from Kamo show that most of the samples are in the sub-alkaline series and the chemical and mineralogical composition of the magma derived from this series is calc-alkaline with a large amount of iron. According to mineralogical, lithological, and geochemical evidence and based on isotopic results, Kamo deposit is a skarn-type deposit.El área de estudio está ubicada a 5.5 km al noreste del condado de Kamo y a 30 km al noreste de Meymeh, Isfahan. El índice de Kamo comprende un anticlinal con una tendencia noroeste-sureste, cuyo afloramiento consiste en arenisca-arenisca y rocas de esquisto jurásico que se encuentran a lo largo de una unidad cretácea. Con base en estudios de campo, así como en investigaciones petrográficas y geoquímicas, los ensambles minerales y minerales en el área incluyen calcopirita, pirita, marcasita y magnetita como minerales primarios y malaquita, bornita, covenita, calcocita, hematita, goetita y óxidos de hierro hidratados como secundarios. Minerales Los minerales secundarios se han formado por oxidación y procesos biogénicos. Las texturas primarias son granulares, diseminadas, en forma de vena y en capas, y las texturas secundarias son en caja y martitizadas, zonas de cizallamiento, reemplazos y vetas. Los factores tectónicos, metamórficos y de oxidación están involucrados en la formación de estas texturas. Debido a la actividad tectónica en esta área y la presencia de fallas, se observan texturas de reemplazo, vetas y corte, que se han desarrollado después de la mineralización. Entre las alteraciones, hematita, propilítico, sericítico, limonítico y caolinítico son altamente prevalentes y son importantes en la formación de depósitos de hierro. Los granitoides subalcalinos de la región están relacionados con la serie orogénica continental de la zona de subducción. Los estudios sobre las muestras de hierro descompuesto de Kamo muestran que la mayoría de las muestras se encuentran en la serie subalcalina y la composición química y mineralógica del magma derivada de esta serie es alcalina con una gran cantidad de hierro. De acuerdo con la evidencia mineralógica, litológica y geoquímica y con base en los resultados isotópicos, el depósito de Kamo es un depósito tipo skarn

    Examen de alteración y zonas metasomáticas basadas en la configuración tectónica de la región Kamoo (noreste de Isfahán, Irán)

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    Kamoo region (northeast of Isfahan) has an anticline structure with a northwest-southeast trend. The exposed part of this anticline consists of siltstone-sandstone and Jurassic shale, which is located below the Cretaceous formation as an unconformity. Penetration by magmatic masses (dikes) and mineralization events are mainly related to fault systems and fractures in the region and follow the trend of the anticline. In addition, the intensity and variety of alterations are affected by tectonic factors, with alteration and metasomatic haloes having developed next to crushed areas. The alteration process is the main controller of mineral mass grade in the study area; therefore, iron grade in the Kamoo ore has increased by the effects of alteration. The alteration effects include propylitic haloes, iron hydroxides (limonite), and clay mineralization (argillic). The host rock consists of Jurassic shales with siltstone, sandstone, and Cretaceous limestone. Calcareous formations adjacent to granodiorite masses are the main hosts of iron skarns. The results of this study showed that the mineral samples from Kamoo were relatively rich in Light Rare Earth Elements (LREEs); the average La/Yb ratio is about 18.61 and Eu anomaly is between 0.52 and 1.94. Based on the findings of this study, the origin for Kamoo skarn was consistent with the model presented by Meinert, and the region’s mineralization and alteration characteristics correspond to the conditions prevailing in oceanic subduction and back-arc basin environments.La región de Kamoo (noreste de Isfahan) tiene una estructura anticlinal con una tendencia noroeste-sureste. La parte expuesta de este anticlinal consiste en arenisca-arenisca y lutita jurásica, que se encuentra debajo de la formación del Cretácico como una disconformidad. La penetración por masas magmáticas (diques) y los eventos de mineralización están relacionados principalmente con sistemas de fallas y fracturas en la región y siguen la tendencia del anticlinal. Además, la intensidad y la variedad de las alteraciones se ven afectadas por factores tectónicos, con la alteración y los halos metasomáticos que se han desarrollado junto a las áreas trituradas. El proceso de alteración es el controlador principal del grado de masa mineral en el área de estudio; por lo tanto, el grado de hierro en el mineral de Kamoo ha aumentado por los efectos de la alteración. Los efectos de alteración incluyen halos propilíticos, hidróxidos de hierro (limonita) y mineralización de arcilla (argílica). La roca huésped consiste en lutitas jurásicas con limolita, arenisca y caliza cretácea. Las formaciones calcáreas adyacentes a las masas de granodiorita son los principales anfitriones de los skarns de hierro. Los resultados de este estudio mostraron que las muestras minerales de Kamoo eran relativamente ricas en elementos de tierras raras ligeras (LREE); la relación media de La / Yb es de aproximadamente 18,61 y la anomalía de Eu es de entre 0,52 y 1,94. Según los hallazgos de este estudio, el origen de Kamoo skarn fue consistente con el modelo presentado por Meinert, y las características de mineralización y alteración de la región corresponden a las condiciones que prevalecen en los entornos de subducción oceánica y cuenca de arco posterior

    Estudios petrográficos e esotópicos en el área de Kamoo, Noreste de Isfahan, Irán

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    The study area is located 5.5 km north-east of Kamo County and 30 km north-east of Meymeh, Isfahan. Kamo Index comprises an anticline with a northwest-southeast trend, the outcrop of which consists of siltstone-sandstone and Jurassic shale rocks that lie along a cretaceous unit. Based on field studies as well as petrographic and geochemical investigations, mineral assemblages and minerals in the area include chalcopyrite, pyrite, marcasite, and magnetite as primary ores and malachite, bornite, covellite, chalcocite, hematite, goethite, and hydrous iron oxides as secondary ores. The secondary ores have been formed by oxidation and biogenic processes. The primary textures are granular, disseminated, vein-shaped, and layered and the secondary textures are boxed and martitized, shear zones, replacements, and veins. Tectonic, metamorphic, and oxidation factors are involved in the formation of these textures. Due to tectonic activity in this area and the presence of faults, replacement, vein, and shear textures, which have developed after mineralization, are observed. Among alterations, hematite, propylitic, sericitic, limonitic, and kaolinitic are highly prevalent and they are important in the formation of iron deposits. The sub-alkaline granitoids of the region are related to the continental subduction-zone orogenic series. Studies on the decomposed iron samples from Kamo show that most of the samples are in the sub-alkaline series and the chemical and mineralogical composition of the magma derived from this series is calc-alkaline with a large amount of iron. According to mineralogical, lithological, and geochemical evidence and based on isotopic results, Kamo deposit is a skarn-type deposit.El área de estudio está ubicada a 5.5 km al noreste del condado de Kamo y a 30 km al noreste de Meymeh, Isfahan. El índice de Kamo comprende un anticlinal con una tendencia noroeste-sureste, cuyo afloramiento consiste en arenisca-arenisca y rocas de esquisto jurásico que se encuentran a lo largo de una unidad cretácea. Con base en estudios de campo, así como en investigaciones petrográficas y geoquímicas, los ensambles minerales y minerales en el área incluyen calcopirita, pirita, marcasita y magnetita como minerales primarios y malaquita, bornita, covenita, calcocita, hematita, goetita y óxidos de hierro hidratados como secundarios. Minerales Los minerales secundarios se han formado por oxidación y procesos biogénicos. Las texturas primarias son granulares, diseminadas, en forma de vena y en capas, y las texturas secundarias son en caja y martitizadas, zonas de cizallamiento, reemplazos y vetas. Los factores tectónicos, metamórficos y de oxidación están involucrados en la formación de estas texturas. Debido a la actividad tectónica en esta área y la presencia de fallas, se observan texturas de reemplazo, vetas y corte, que se han desarrollado después de la mineralización. Entre las alteraciones, hematita, propilítico, sericítico, limonítico y caolinítico son altamente prevalentes y son importantes en la formación de depósitos de hierro. Los granitoides subalcalinos de la región están relacionados con la serie orogénica continental de la zona de subducción. Los estudios sobre las muestras de hierro descompuesto de Kamo muestran que la mayoría de las muestras se encuentran en la serie subalcalina y la composición química y mineralógica del magma derivada de esta serie es alcalina con una gran cantidad de hierro. De acuerdo con la evidencia mineralógica, litológica y geoquímica y con base en los resultados isotópicos, el depósito de Kamo es un depósito tipo skarn

    Examen de alteración y zonas metasomáticas basadas en la configuración tectónica de la región Kamoo (noreste de Isfahán, Irán)

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    La región de Kamoo (noreste de Isfahan) tiene una estructura anticlinal con una tendencia noroeste-sureste. La parte expuesta de este anticlinal consiste en arenisca-arenisca y lutita jurásica, que se encuentra debajo de la formación del Cretácico como una disconformidad. La penetración por masas magmáticas (diques) y los eventos de mineralización están relacionados principalmente con sistemas de fallas y fracturas en la región y siguen la tendencia del anticlinal. Además, la intensidad y la variedad de las alteraciones se ven afectadas por factores tectónicos, con la alteración y los halos metasomáticos que se han desarrollado junto a las áreas trituradas. El proceso de alteración es el controlador principal del grado de masa mineral en el área de estudio; por lo tanto, el grado de hierro en el mineral de Kamoo ha aumentado por los efectos de la alteración. Los efectos de alteración incluyen halos propilíticos, hidróxidos de hierro (limonita) y mineralización de arcilla (argílica). La roca huésped consiste en lutitas jurásicas con limolita, arenisca y caliza cretácea. Las formaciones calcáreas adyacentes a las masas de granodiorita son los principales anfitriones de los skarns de hierro. Los resultados de este estudio mostraron que las muestras minerales de Kamoo eran relativamente ricas en elementos de tierras raras ligeras (LREE); la relación media de La / Yb es de aproximadamente 18,61 y la anomalía de Eu es de entre 0,52 y 1,94. Según los hallazgos de este estudio, el origen de Kamoo skarn fue consistente con el modelo presentado por Meinert, y las características de mineralización y alteración de la región corresponden a las condiciones que prevalecen en los entornos de subducción oceánica y cuenca de arco posterior

    Examen de alteración y zonas metasomáticas basadas en la configuración tectónica de la región Kamoo (noreste de Isfahán, Irán)

    Get PDF
    Kamoo region (northeast of Isfahan) has an anticline structure with a northwest-southeast trend. The exposed part of this anticline consists of siltstone-sandstone and Jurassic shale, which is located below the Cretaceous formation as an unconformity. Penetration by magmatic masses (dikes) and mineralization events are mainly related to fault systems and fractures in the region and follow the trend of the anticline. In addition, the intensity and variety of alterations are affected by tectonic factors, with alteration and metasomatic haloes having developed next to crushed areas. The alteration process is the main controller of mineral mass grade in the study area; therefore, iron grade in the Kamoo ore has increased by the effects of alteration. The alteration effects include propylitic haloes, iron hydroxides (limonite), and clay mineralization (argillic). The host rock consists of Jurassic shales with siltstone, sandstone, and Cretaceous limestone. Calcareous formations adjacent to granodiorite masses are the main hosts of iron skarns. The results of this study showed that the mineral samples from Kamoo were relatively rich in Light Rare Earth Elements (LREEs); the average La/Yb ratio is about 18.61 and Eu anomaly is between 0.52 and 1.94. Based on the findings of this study, the origin for Kamoo skarn was consistent with the model presented by Meinert, and the region’s mineralization and alteration characteristics correspond to the conditions prevailing in oceanic subduction and back-arc basin environments.La región de Kamoo (noreste de Isfahan) tiene una estructura anticlinal con una tendencia noroeste-sureste. La parte expuesta de este anticlinal consiste en arenisca-arenisca y lutita jurásica, que se encuentra debajo de la formación del Cretácico como una disconformidad. La penetración por masas magmáticas (diques) y los eventos de mineralización están relacionados principalmente con sistemas de fallas y fracturas en la región y siguen la tendencia del anticlinal. Además, la intensidad y la variedad de las alteraciones se ven afectadas por factores tectónicos, con la alteración y los halos metasomáticos que se han desarrollado junto a las áreas trituradas. El proceso de alteración es el controlador principal del grado de masa mineral en el área de estudio; por lo tanto, el grado de hierro en el mineral de Kamoo ha aumentado por los efectos de la alteración. Los efectos de alteración incluyen halos propilíticos, hidróxidos de hierro (limonita) y mineralización de arcilla (argílica). La roca huésped consiste en lutitas jurásicas con limolita, arenisca y caliza cretácea. Las formaciones calcáreas adyacentes a las masas de granodiorita son los principales anfitriones de los skarns de hierro. Los resultados de este estudio mostraron que las muestras minerales de Kamoo eran relativamente ricas en elementos de tierras raras ligeras (LREE); la relación media de La / Yb es de aproximadamente 18,61 y la anomalía de Eu es de entre 0,52 y 1,94. Según los hallazgos de este estudio, el origen de Kamoo skarn fue consistente con el modelo presentado por Meinert, y las características de mineralización y alteración de la región corresponden a las condiciones que prevalecen en los entornos de subducción oceánica y cuenca de arco posterior

    Review of Geochimical, Isotopic and Fluid Inclusions Studies in Ramand Region (Qazvin Province)

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    Ramand copper deposit is an example of vein-bearing deposits with volcanic host located in the Urumieh-Dokhtar zone. The deposit host is an Eocene volcanic sequence and the main host’s rock is the rhyolite mineral. The main minerals are chalcopyrite, pyrite, covellite and natural gold; and the tailings minerals include quartz, calcite and sericite. The average grade of gold in silica veins is 133.5 ppb, the average grade of copper is about 3.5% and the average grade of molybdenum is 135 ppm. Quartz-sulfide hydrothermal veins contain biphasic fluid-rich fluid inclusions and monophasic fluid-rich fluid inclusions. The homogenization temperature ranged from 73 to 307 ° C with an average of 141 ° C and in all samples, homogenization was carried out through the liquid phase and salinity variations ranged from 1.75 to 4.74 with an average of 3.65 wt% NaCl equivalent. Quartz and calcite oxygen isotope values range between 4.4 to 9.4 per thousand. Isotopic data indicate that the ore-generating fluids in the Ramand ore deposit have relatively low salinity and atmospheric-magmatic origin. According to this study, Ramand’s mineralization range is the result of hydrothermal activity in the area where mineralization with simple mineralogical characteristics has occurred in siliceous veins and sub-veinsO depósito de cobre de Ramand é um exemplo de depósitos contendo veias de origem vulcânica localizado na zona de Urumieh-Dokhtar. O depósito é uma sequência de origem vulcânica do Eoceno e a rocha principal encontrada na área é o riolito. Os principais minerais são calcopirita, pirita, covellite e ouro natural; e os minerais de rejeitos incluem quartzo, calcita e sericita. O teor médio de ouro nas veias de sílica é de 133,5 ppb, o teor médio de cobre é de cerca de 3,5% e o teor médio de molibdênio é de 135 ppm. As veias hidrotermais de sulfeto de quartzo contêm inclusões fluidas ricas em líquidos bifásicos e inclusões fluidas ricas em líquidos monofásicos. A temperatura de homogeneização variou de 73 a 307°C com uma média de 141°C e em todas as amostras, a homogeneização foi realizada na fase líquida e as variações de salinidade variaram de 1,75 a 4,74 com uma média de 3,65% em peso de NaCl equivalent

    Performance of An Airlift Membrane Bioreactor Under Different Aeration Rates

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    The treatment of a synthetic oily wastewater in an airlift submerged membrane bioreactor (AMBR) has been studied. A flat sheet Kubota membrane has been used for this purpose in the reactor with a working volume of 19 L. The volumetric oxygen transfer coefficient, oxygen uptake rate, treatment efficiency and fouling intensity were investigated for various aeration rates (0.2, 0.5, 0.7 and 1 m3/h). Based on the results, a COD removal efficiency of more than 93% - even for the lowest aeration rate – is reported. However, increasing the aeration rate resulted in higher kLa and higher microbial activity. The high aeration intensity resulted in breakage of activated sludge flocs and hence reduction in mean flocs size and release of extracellular polymeric substances (EPS). At an aeration intensity as high as 1m3/h, the maximum irreversible fouling was observed which is due to higher concentration of EPS and colloids that are the major foulants. Although the aeration may scour the membrane surface and avoid the formation of cake layer, it could induce more pore blocking fouling. In the studied range, the 0.7 m3/h is found to be the optimum aeration rate and the alteration of the aeration rate deteriorated the AMBR’s performance

    Application of fractal geometry for recognizing the pattern of textural zoning in epithermal deposits (case study: Sheikh-Darabad Cu-Au indices, East-Azarbaijan province)

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    Isotopic and microthermometry results from Sheikh-Darabad Cu-Au indices in Mianeh region, East-Azarbaijan province, indicate Cenozoic post-magmatic activities with developed adularia facies through an extended and Neogene related alteration that is given rise to occurring silica vein systems as the main hosting locations for epithermal mineralization. The research evidence also has been coincided with Queensland textural zoning conclusions which confirm a success case of silica textural variations associated with Sheikh-Darabad gold and copper bearing locations based on paragenesis of quartz-pyrite-chalcopyrite. As a new result, fractal-based geometry has been used for assessing the nonlinear distribution of siliceous components and subsequently for prognosis of gold mineralization potential in Sheikh-Darabad region. In practice, most of quartzitic occurrences and related textural variations have been precisely studied and realized by satisfying to silica power law statement in order to obtain the self-similar peculiarities of individual textures. Therefore, using a textural pattern for evaluating and correlating between silica zonal variations and its ordinary textural evolutions in post-magmatic environments, is a new criterion for prospecting precious metals with finally emphasizing on gold exploration priorities in Sheikh-Darabad region

    pplication of Fractal Technique for Analysis of Geophysical - Geochemical Databases in Tekieh Pb-Zn Ore Deposit (SE of Arak)

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    Introduction Tekieh Lead-Zinc ore deposit that is located in the Sanandaj-Sirjan structural zone has been recognized as one of the most important mineralized regions in Malayer-Isfahan metallogenic sub-state, south east of Arak (Momenzadeh and Ziseman, 1981). Carbonate host units have been developed along (or across) the Vishan-Tekieh anticline as the main structure extended in NW-SE trends (Annells et al, 1985). According to geochemical investigations (Salehi, 2004), the element content of the mineralized regions has originated from Alpine post-volcanisms and subsequently it has migrated toward early Cretaceous formations (dolomitic limestones) among several hypogenic stages (Torkashvand et a.2009). Also echelon type structures consisting of folded systems and inversed faulting of structures are the most common features in western and eastern parts of ore deposit regions (Annells et al, 1985). Syngenetic enrichments beside limited (rarely developed) epigenetic mineralization have been known as two main phases which are closely relevant to ore forming processes in the massive lenses and vein type occurrences, respectively (Momenzadeh and Ziseman, 1981). Material and Methods In this research, two statistical techniques that consist of classical and fractal equations (Mandelbrot, 2005) were applied in geochemical (Torkashvand et al., 2009) and geophysical (Jafari, 2007) databases for obtaining the linear and nonlinear distributions of geochemical elements (Tekieh Pb-Zn content) in association with resistivity variations and induction polarization measurements (Calagari, 2010). According to linear statistical techniques (Torkashvand et al., 2009), the main central parameters such as mean, median and mode in addition to variances and standard deviations as distribution tendencies could be used for obtaining the regression coefficients of the databases. However, in fractal statistics, a reliable regression between geoelectrical - geochemical anomalies should be calculated based on measuring the fractal dimensional variations in the recursive patterns (Mehrnia, 2013). In practice, the Area-Concentration equations (Mandelbrot, 2005) were applied in resistivity, induction polarization, Pb and Zn datasets for achieving the nonlinear relationships in anomalous regions which were characterized by increasing in regression coefficients with more spatial correlation of the variable than linear statistics (Mehrnia, 2013). Results and Discussion This research showed that both linear and nonlinear statistics are able to estimate the spatial association of geochemical anomalies with geophysical variables. A meaningful increase in the regression coefficient was also revealed after measuring the self-similar peculiarities of concentration values on gridded plots (Salehi, 2004; Torkashvand et al., 2009). From the fractal point of view, Pb ore-minerals have been deposited in the western sub-region, while Zn mineralization seems to be extended in the depth of eastern alterations. Also a predictable geochemical zonation can be considered in the western target (meaningful Pb anomalies) that is more patterned than the eastern halos according to geological observations (Momenzadeh and Ziseman, 1981) and mineralogical evidences (Salehi, 2004). An increase in Supra ore/Sub ore proportional content was measured in the western sub-region which indicated more reliable potential of Pb mineralization (Galena as a particular indication of sulfide-rich minerals) than the same phases of ore forming processes in the eastern sub-region, although the content of Pb-ores rapidly decreases in the eastern target and is replaced by Zn minerals (Sphalerite as particular indication of sulfide-rich mineralization). Because power law relationships are significant in both geochemical and geophysical anomalies (Mehrnia, 2013) a detailed program including borehole geophysics and litho-geochemical land-surveys should be considered in the prospected regions. Therefore, upcoming phases should emphasize on self-organized distribution of Pb-Zn anomalies to introduce a new set of nonlinear distributions in order to find the confidence regression coefficients between the variables. As the final results, fractal analysis of available databases represented new target areas with better mineralization aggregations than linear analysis of the anomalous regions according to micrographs. It means that surficial mineralization processes could be extended in depth and enriched next to altered host units because of a nonlinear but self-organized distribution of geochemical- geophysical anomalies in Tekieh ore deposit region. References Annells, R.N., Arthurton, R.S., Bazley, R.A.B., Davies, R.G., Hamedi, M.A.R. and Rahimzadeh, F.R., 1985. Geological Map of Shazand- Khomein. Scale: 1:100000, Cartographic Department of Geological Survey of Iran. Calagari, A.A., 2010. Principles of geophysical explorations. University of Tabriz, Tabriz, 485 pp. Jafari, H., 2007. Using geoelectrical techniques for Zn-Pb explorations in Haft-Emarat district, Tekieh region (South East of Arak). Kimya Kavan Tosee Novin Company, Tehran, 206 pp. Mandelbrot, B., 2005. Fractal Geometry of Nature. W.H Freeman & Company, New York, 468 pp. Mehrnia, S.R.,2013. Application of fractal geometry for recognizing the pattern of textural zoning in epithermal deposits: (case study: Shikhdarabad Au-Cu indices East- Azerbaijan province). Journal of Economic Geology, 5(1): 23-36. (in Persian) Momenzadeh, M. and Ziseman, H., 1981. Lead – Zinc re mineralization potentials in Malayer – Esfahan district. Journal of Ore Deposit, 3(1): 88-101. Salehi, L., 2004. Geochemistry of REE content in Tekieh Pb-Zn ore deposit. M.Sc. Thesis, Shahid Beheshti University, Tehran, Iran, 181 pp. Torkashvand, S., Mehrnia, S.R. and Moghaddasi, S.J., 2009. Co-Processing of the geophysical parameters for Tekieh Zn-Pb ore deposits (south east of Arak). 4th PNU Geological National Conference, Payam Noor University of Mashhad, Mashhad, Iran

    Experimental Study and Modeling of Fouling in Immersed Membrane Bioreactor Operating in Constant Pressure Filtration

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    A new mathematical model is proposed based on filtration mechanisms for the prediction of fouling in airlift immersed membrane bioreactors (iMBRs). The cake formation on the membrane surface through constant pressure filtration process in the iMBR was explained by a proposed cake filtration mechanism which assumes that no particle enters the pores when forming the cake layer on the membrane surface. The cake porosity reduction due to diffusion of particles was described by an intermediate blocking mechanism. Experimental study of fouling was also performed in a lab-scale airlift flat-sheet iMBR operating at constant vacuum. The mixed liquor suspended solid (MLSS) concentration was changed within the range of 5000 to 15000 mg/L, while the superficial air velocity was varied between 32 and 128 m3/m2/h. The presented model includes two parameters, that is, ultimate filtration resistance and initial rate of cake formation. The effect of the MLSS concentration and superficial air velocity on the parameters of the proposed model was studied. The results obtained from the model demonstrated that the ultimate filtration resistance and the initial rate of cake formation are more sensitive to the aeration rate at lower superficial velocities. It was also shown that the ultimate filtration resistance has a linear relation with MLSS concentration. A good agreement exists between the results of the model and the experimental data. The proposed model also showed a better compatibility with the experimental data compared to other fouling models available in the literature
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