Abstract: The waste considered for this study was the effluent of the pulping process produced du... more Abstract: The waste considered for this study was the effluent of the pulping process produced during the manufacture of pulp and paper in the Rakta integrated pulp and paper mill in Alexandria. The pulping process in Rakta mill is conducted under pressure of 7-8 bar, 165°C using 10 % NaOH based on straw weight for 2 h. The spent liquor after alkali cooking contains any where 8 to 15 % solids in solution and primarily these dissolved solids are lignin and dissolved carbohydrates. The effect of some operating parameters on the performance of the Using Up-flow Anaerobic Sludge Blanket was studied; these include mainly the organic loading rate and hydraulic retention time. The gas production rate increased to 3.43 m 3 biogas/(m 3 reactor volume. day), by increasing the Biochemical Oxygen Demand (BOD) loading rate to 16 kg BOD feed/(m 3 reactor volume. day), with a gas yield of 0.66 m 3 biogas/(kg reduced organic matter). The efficiency was reduced by increasing the loading rate. Thus b...
The present work aims to study the drought stress effects on polyamine content and its relationsh... more The present work aims to study the drought stress effects on polyamine content and its relationship with growth and development in seeds, during cell division (from the beginning and until 17 days after pollination) and grain filling (until reaching the physiological maturity) stages. Factorial experiment based on Randomized Complete Block (RCB) design was carried out with three replications. Two factors of the experiment were considered: the level of irrigation (irrigation without and with drought stress during cell division stage and with drought stress during grain filling stage) and the level of wheat genotype (drought-resistant, semi-resistant and sensitive genotypes). As control treatment, soil moisture content of the field was considered. For droughtstress treatment, the 50% of the soil moisture content in control treatment was established. According to the experimental results, Putrescine content value is higher in control treatment which develops seeds of drought-resistant genotypes than that are registered for semi-resistant and sensitive genotypes. Both drought stress treatments induced significant rises in putrescine amount in the different genotypes of the study. The rises of putrescine content in sensitive and semi-resistant genotypes, however, were higher than in resistant ones, and the highest rise in putrescine content appeared in manning semi-resistant genotype during the stage of grain filling (27 days after pollination).
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
In the Eocene part of the Siwa Oasis, the larger foraminifera are represented by the genera Nummu... more In the Eocene part of the Siwa Oasis, the larger foraminifera are represented by the genera Nummulites, Arxina, Operculina, Sphaerogypsina, Asterocyclina, Grzybowskia, Silvestriella, Gaziryina and Discocyclina in order of abundance. Operculina continues up to the early Oligocene as modern representatives in tropical regions, while the other genera became extinct. Nevertheless, the most common larger foraminiferal genus Lepidocyclina (Nephrolepidina) appears only in the lowermost Oligocene. In spite of the Eocene-Oligocene (E/O) transition is thought to have been attended by major continental cooling at northern middle and high latitudes, we discover that at the Siwa Oasis, there is a clear warming trend from the late Eocene (extinction level of Nummulites, Sphaerogypsina, Asterocyclina, Grzybowskia, Silvestriella and Discocyclina) to the early Oligocene is observed due to the high abundance of Operculina and occurrence of kaolinite and gypsiferous shale deposits in both Qatrani and El Qara formations (Oligocene) at this transition. The El Qara Formation is a new rock unit proposed herein for the Oligocene (Rupelian age) in the first time. Several episodes of volcanic activity occurred in Egypt during the Cenozoic. Mid Tertiary volcanicity was widespread and a number of successive volcanic pulses are starting in the late Eocene. The release of mantle CO 2 from this very active volcanic episode may have in fact directly caused the warm Eocene-Oligocene greenhouse climate effect.
In this work, the process performance of an anaerobic batch reactor for the methane production fr... more In this work, the process performance of an anaerobic batch reactor for the methane production from glucose-containing wastewater was studied. The anaerobic sludge taken from UASB reactor was operated on flax retting wastewater and activated seeding sludge from Zenin wastewater treatment plant. The anaerobic batch reactor was operated at ambient temperature, a hydraulic reaction time (HRT) of 24 h, and different chemical oxygen demand (COD) loading rates from 10 to 50 kgm −3 d −1 without and with pH control at 7. The results showed that at the optimum COD loading rate of 40 kgm −3 d −1 and pH 7. At these optimum conditions, the highest methane yield was 0.95 l methane/g glucose consumed. Under the optimum COD-to-nitrogen (COD: N) ratio of 100:2.4, the system with pH controlled at 7 gave the highest specific methane production rate of 30 l methane l −1 d −1
The application of kinetic models (Monod, Contois and Chen & Hashimoto) and overall microbial kin... more The application of kinetic models (Monod, Contois and Chen & Hashimoto) and overall microbial kinetic on the Up-flow Anaerobic Sludge Blanket Reactor (UASB) for treatment of flax retting wastewater was investigated. The system consists of a UASB reactor and six steady states were attained over a range of COD loading rates of 1.5-8.6 kg COD/m 3 /d. The results of all six steady states were successfully fitted above 96% for three known kinetics. The growth yield coefficient, Y, was found to be 0.74 gVSS/gCOD while the specific microorganism decay rate was 0.20 d -1 . The k values were in the range of 0.3 - 0.523 gCOD/gVSS/d and µmax values were between 0.259 and 0.352 d -1 . The COD removal efficiency was 90.5-64.5% with HRT of 72-12 hrs. The system efficiency was greatly influenced by SRT and OLRs.
One of the methods to prepare nano-crystals metal oxide (MgO) is by using a precipitation method.... more One of the methods to prepare nano-crystals metal oxide (MgO) is by using a precipitation method. Magnesium oxalate as a valuable chemical almost produced in pure grade from seawater bittern by precipitation process. In this paper, kinetics of magnesium oxalate precipitation from sea bittern was studied. The rate constants determined at different temperatures, Molar ratios and pH. The activation parameters were also calculated. Sea bittern from salt production unit of El-Mex saline company is containing about 85.7 g.L -1 Mg 2+ . Detailed characterization involving XRD, TEM and TGA was investigated. The results show that The precipitation of magnesium oxalate from sea bittern is first order with respect to the concentration of magnesium oxalate at pH=4, MR=1:1 and temp.=25 °C Also, The rate constant doesn't strongly affected by increasing temperature so the optimum operating reaction temperature is 25 °C. The spherical Magnesium oxalate with uniform diameter of about 0.5 μm was o...
Magnesium gluconate was prepared as a medication product under ordinary conditions and is soluble... more Magnesium gluconate was prepared as a medication product under ordinary conditions and is soluble in water. Magnesia combine with both citric acid and gluconic acid as magnesium gluconate. The dry product mixed with a suitable amount of bicarbonate and heated under 300 oC is the equivalent in strength of magnesia solution and having a therapeutic effect. Analytical technique like, XRD, FTIR, UV Vis spectroscopy, TGA/ DTA and DSC were used to study properties of magnesium gluconate prepared. The product proved to be crystalline with wave length for maximum UV absorbance 197 nm. The DSC thermogram of the analyte indicated that product is stable up to 275 oC. Thus, it concludes that magnesium gluconate with crystal size 0.63-0.68 nm is a useful pharmaceutical and nutraceutical for industries. Besides when mixed with carbonate and heated up to 400 oC Periclase is produced as an essential product for different chemical industries.
Abstract Rice husk (RH) is produced in large quantities in Egypt and burned in open atmosphere to... more Abstract Rice husk (RH) is produced in large quantities in Egypt and burned in open atmosphere to produce RH ash (RHA), which poses a great risk to the environment by affecting the land and the surrounding areas in which it is disposed of. Consequently, this work is an attempt to prepare a modified sand/lime brick, employing a mixture of sand and different percentages of RHA (5%, 10%, and 15%) with 15% of burned calcite. The compressive strength and bulk density of the prepared sand bricks were determined. Further, the phase composition and structure of the surface of the samples were also identified by Fourier-transform infrared (FT–IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) techniques. It was confirmed that the modified sand/lime brick, composed of 80% sand, 5% RHA, and 15% lime, exhibited the best results. The obtained bulk density and compressive strength were 1.82 g/cm3 and 103 kg/cm2, respectively. A comparative estimation of the unit cost of the modified RHA–sand/lime brick and those of two other brick types, namely clay/RH and cement/RHA bricks, which had been prepared and reported by the authors, was performed. It was concluded that the partial replacement of RH, as solid agricultural waste, in the manufacture of building bricks can reduce the cost significantly, as 20% RH substitution (yielding 5% RHA) in the sand brick, 10% RH substitution in the clay brick, and also 20% RH substitution (yielding 5% RHA) in the cement brick, resulting in 14%, 42.8%, and 25% unit cost reductions, respectively.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Research Journal of Pharmaceutical, Biological and Chemical Sciences
Removal of nutrients such as ammonium and phosphate ions by natural or synthetic zeolite has been... more Removal of nutrients such as ammonium and phosphate ions by natural or synthetic zeolite has been studied on lab and pilot scales using an orbital shaker and mechanically stirred batch system respectively. Natural Zeolites are abundant and low cost resources. Due to their high cation-exchange ability as well as to the molecular sieve properties, natural zeolite has been widely used as adsorbents in separation and purification processes in post decades. The aim of the present study is to investigate adsorption and desorption behavior of Zeolite and activated carbon in removal of ammonium and phosphate from sewage wastewater (SWW). The lab scale was studied for the direct precipitation of struvite by adding bittern and crystallization of final product. On The pilot scale study the adsorbed/desorbed ammonium and phosphorous from 100 liter of (SWW) on Zeolite were precipitated by adding bittern as low cost source of magnesium ion. The Langmuir equation was fitted to the data points as 1...
Effect of gradually substitution of ordinary Portland cement by a few percent of silica fume (0.0... more Effect of gradually substitution of ordinary Portland cement by a few percent of silica fume (0.0, 2.5, 5.0 and 7.5 wt.%) on the durability of slag-Portland cement pastes up to 12 months immersed in sea water was investigated. The results show that the substitution of Portland cement by silica fume in the granulated slag-Portland cement pastes improves the physico-mechanical properties of the hardened cement pastes especially at early ages as well as gives a better resistance of cement stone to sea water attack at all immersing time. Also, the composite cement pastes containing 7.5% silica fume showed a maximum durability than other samples.
Investigations were carried out for making building bricks from Abu Zaabal altered basalt and de-... more Investigations were carried out for making building bricks from Abu Zaabal altered basalt and de-aluminated kaolin wastes. Samples were made from mixtures containing 90–70 % basalt and 10–30 % de-aluminated kaolin. Samples were prepared and dried at 105 °C as well as fired at different temperatures ranging from 900 to 1100 °C for 2 h soaking time. The physico-mechanical ceramic properties of the dried and fired samples were investigated. The study revealed that good quality bricks can be produced from 90–70 % basalt and 10–30 % de-aluminated kaolin.
The performance of UASB (Up-flow Anaerobic Sludge Blanket) reactor was investigated in the presen... more The performance of UASB (Up-flow Anaerobic Sludge Blanket) reactor was investigated in the present study for treatment of flax retting wastewater. Batch and continuous experiments on a pilot scale were designed. The initial seed for granules (bacteria acclimation) formed earlier was from municipal sewage treatment plant with VSS of 18-20 g/L. Batch experiments proved that the sludge retention time (SRT) was 77 days. Under steady state conditions, continuous experiments were conducted at organic loading rates (OLRs) in the range of 1.2 to 8.6 kg CODs m-3 •d-1 , where the hydraulic retention time (HRT) decreased from 72 to 12 hrs. The results proved that the UASB technology provides good COD removal efficiency from 64.5% to 90.5% as COD loading rate decreased and good biogas production at proper food: microorganism (F:M) ratios.
A mixture of different types of clay was blended with rice straw (RS) and microcrystalline cellul... more A mixture of different types of clay was blended with rice straw (RS) and microcrystalline cellulose (MCC) in the presence or absence of cement kiln dust (CKD) to produce new types of brick. The ratios of RS and MCC were 0, 5, and 10% w/w in the absence of CKD while they were kept at 5% w/w in its presence. The samples produced were compared to "blended" bricks prepared using 10% w/w CKD. Samples were fired at temperatures up to 1000 C and their surface and composition studied using SEM and XRD. Moreover, the chemical and physical properties of prepared bricks were determined. Introducing RS reduced both strength and bulk density but increased porosity of prepared samples. The presence of MCC alone increased the compressive strength, while combining RS with CKD overcame the decrease in strength resulting from the presence of RS alone. This has enabled the production of lightweight low-cost bricks with a compressive strength close to nonblended bricks, especially at high firing temperature.
Huge quantity of rice husk ash (RHA) and broken ceramics in Egypt are produced as wastes and beco... more Huge quantity of rice husk ash (RHA) and broken ceramics in Egypt are produced as wastes and become of great threat to the environment, causing damage to the land and the surrounding areas in which it is dumped. In addition, production of cement is responsible for about 7% of all CO2 generated in the world. For that, the aim of the present research is to produce modified cement bricks by replacing cement partially by RHA and broken ceramic wastes, to bring a substantial reduction for CO2 emitted every year in the atmosphere, and to reuse agricultural and industrial solid wastes. Therefore two sets of experiments were investigated by replacing part of Ordinary Portland Cement (OPC) with: 1) RHA and 2) mixture of RHA and ceramic wastes, to produce modified cement bricks, at different curing time, namely7,14 and 28 days. Characterizations of raw materials used for the target preparation were carried out covering: free silica and organic matters, XRD, TGA, and DTA. The cold and boiling ...
Open Journal of Chemical Engineering and Science, 2014
Anaerobic Digestion is a series of chemical reactions during which organic material is decomposed... more Anaerobic Digestion is a series of chemical reactions during which organic material is decomposed through the metabolic pathways of naturally occurring microorganisms in an oxygendepleted environment. In nature this type of breakdown typically occurs in warm wet and dark environments, such as in the digestive tracts. The microorganisms are exploited in the biotechnological process of anaerobic digestion both to reduce the pollution caused by organic wastes and to produce methane, which can be used as a fuel. The number and types of microorganisms present in digesters are likely to depend upon the type of digester, its operating conditions and the waste composition. Anaerobic Digesters can be used on any carbon containing industrial wastewater i.e. food processing; pulp and paper; sugar and distillery; slaughterhouse; cheese whey and diary units; brewing industry and municipal sludge. Also, they provide an effective method for turning residues from different wastes, biogas (rich in methane which can be used to generate heat and/or electricity); fiber (this can be used as a nutrient-rich soil conditioner) and liquor (this can be used as liquid fertilizer). In the review paper, the special emphasis on some of the environmental requirements; indicators of treatment unbalance; types of high rate anaerobic reactors; the application of anaerobic fermentation of selected high strength industrial wastewaters; modelling of anaerobic digestion, and finally, there is a case study.
The influence of substitution of Ordinary Portland cement by ground granulated blast-furnace slag... more The influence of substitution of Ordinary Portland cement by ground granulated blast-furnace slag up to 70% on the properties of silica fume-Portland cement composite pastes up to 12 months was studied. After one year, the composite cements pastes containing 50-70% slag exhibit suitable strength values compared to without slag sample. Also, XRD results show that the C-S-H are intensified with available increase indicating more dense structures and large amount of additional C-S-H in the presence slag content.
American Journal of Engineering and Applied Sciences, 2015
This work aimed to study the effect of the dosage of laboratory synthesized Sulfonated Acetone Fo... more This work aimed to study the effect of the dosage of laboratory synthesized Sulfonated Acetone Formaldehyde (SAF) on the physicmechanical characteristics and durability of SF-SRC cement pastes immersed in 4% MgCl 2 or 4% MgSO 4 solutions or at elevated temperatures up to 800°C. The compressive strength of thermally treatment cement pastes with 1.5% SAF increases up to 600°C, then decreases up to 800°C. Presence of 2.0% SAF works to produce a compact cementing structure, which decreases the accessibility of the penetration of chloride as well as sulphate ion penetration and enhances the durability, hence the total chloride and sulphate contents diminished.
Abstract: The waste considered for this study was the effluent of the pulping process produced du... more Abstract: The waste considered for this study was the effluent of the pulping process produced during the manufacture of pulp and paper in the Rakta integrated pulp and paper mill in Alexandria. The pulping process in Rakta mill is conducted under pressure of 7-8 bar, 165°C using 10 % NaOH based on straw weight for 2 h. The spent liquor after alkali cooking contains any where 8 to 15 % solids in solution and primarily these dissolved solids are lignin and dissolved carbohydrates. The effect of some operating parameters on the performance of the Using Up-flow Anaerobic Sludge Blanket was studied; these include mainly the organic loading rate and hydraulic retention time. The gas production rate increased to 3.43 m 3 biogas/(m 3 reactor volume. day), by increasing the Biochemical Oxygen Demand (BOD) loading rate to 16 kg BOD feed/(m 3 reactor volume. day), with a gas yield of 0.66 m 3 biogas/(kg reduced organic matter). The efficiency was reduced by increasing the loading rate. Thus b...
The present work aims to study the drought stress effects on polyamine content and its relationsh... more The present work aims to study the drought stress effects on polyamine content and its relationship with growth and development in seeds, during cell division (from the beginning and until 17 days after pollination) and grain filling (until reaching the physiological maturity) stages. Factorial experiment based on Randomized Complete Block (RCB) design was carried out with three replications. Two factors of the experiment were considered: the level of irrigation (irrigation without and with drought stress during cell division stage and with drought stress during grain filling stage) and the level of wheat genotype (drought-resistant, semi-resistant and sensitive genotypes). As control treatment, soil moisture content of the field was considered. For droughtstress treatment, the 50% of the soil moisture content in control treatment was established. According to the experimental results, Putrescine content value is higher in control treatment which develops seeds of drought-resistant genotypes than that are registered for semi-resistant and sensitive genotypes. Both drought stress treatments induced significant rises in putrescine amount in the different genotypes of the study. The rises of putrescine content in sensitive and semi-resistant genotypes, however, were higher than in resistant ones, and the highest rise in putrescine content appeared in manning semi-resistant genotype during the stage of grain filling (27 days after pollination).
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
In the Eocene part of the Siwa Oasis, the larger foraminifera are represented by the genera Nummu... more In the Eocene part of the Siwa Oasis, the larger foraminifera are represented by the genera Nummulites, Arxina, Operculina, Sphaerogypsina, Asterocyclina, Grzybowskia, Silvestriella, Gaziryina and Discocyclina in order of abundance. Operculina continues up to the early Oligocene as modern representatives in tropical regions, while the other genera became extinct. Nevertheless, the most common larger foraminiferal genus Lepidocyclina (Nephrolepidina) appears only in the lowermost Oligocene. In spite of the Eocene-Oligocene (E/O) transition is thought to have been attended by major continental cooling at northern middle and high latitudes, we discover that at the Siwa Oasis, there is a clear warming trend from the late Eocene (extinction level of Nummulites, Sphaerogypsina, Asterocyclina, Grzybowskia, Silvestriella and Discocyclina) to the early Oligocene is observed due to the high abundance of Operculina and occurrence of kaolinite and gypsiferous shale deposits in both Qatrani and El Qara formations (Oligocene) at this transition. The El Qara Formation is a new rock unit proposed herein for the Oligocene (Rupelian age) in the first time. Several episodes of volcanic activity occurred in Egypt during the Cenozoic. Mid Tertiary volcanicity was widespread and a number of successive volcanic pulses are starting in the late Eocene. The release of mantle CO 2 from this very active volcanic episode may have in fact directly caused the warm Eocene-Oligocene greenhouse climate effect.
In this work, the process performance of an anaerobic batch reactor for the methane production fr... more In this work, the process performance of an anaerobic batch reactor for the methane production from glucose-containing wastewater was studied. The anaerobic sludge taken from UASB reactor was operated on flax retting wastewater and activated seeding sludge from Zenin wastewater treatment plant. The anaerobic batch reactor was operated at ambient temperature, a hydraulic reaction time (HRT) of 24 h, and different chemical oxygen demand (COD) loading rates from 10 to 50 kgm −3 d −1 without and with pH control at 7. The results showed that at the optimum COD loading rate of 40 kgm −3 d −1 and pH 7. At these optimum conditions, the highest methane yield was 0.95 l methane/g glucose consumed. Under the optimum COD-to-nitrogen (COD: N) ratio of 100:2.4, the system with pH controlled at 7 gave the highest specific methane production rate of 30 l methane l −1 d −1
The application of kinetic models (Monod, Contois and Chen & Hashimoto) and overall microbial kin... more The application of kinetic models (Monod, Contois and Chen & Hashimoto) and overall microbial kinetic on the Up-flow Anaerobic Sludge Blanket Reactor (UASB) for treatment of flax retting wastewater was investigated. The system consists of a UASB reactor and six steady states were attained over a range of COD loading rates of 1.5-8.6 kg COD/m 3 /d. The results of all six steady states were successfully fitted above 96% for three known kinetics. The growth yield coefficient, Y, was found to be 0.74 gVSS/gCOD while the specific microorganism decay rate was 0.20 d -1 . The k values were in the range of 0.3 - 0.523 gCOD/gVSS/d and µmax values were between 0.259 and 0.352 d -1 . The COD removal efficiency was 90.5-64.5% with HRT of 72-12 hrs. The system efficiency was greatly influenced by SRT and OLRs.
One of the methods to prepare nano-crystals metal oxide (MgO) is by using a precipitation method.... more One of the methods to prepare nano-crystals metal oxide (MgO) is by using a precipitation method. Magnesium oxalate as a valuable chemical almost produced in pure grade from seawater bittern by precipitation process. In this paper, kinetics of magnesium oxalate precipitation from sea bittern was studied. The rate constants determined at different temperatures, Molar ratios and pH. The activation parameters were also calculated. Sea bittern from salt production unit of El-Mex saline company is containing about 85.7 g.L -1 Mg 2+ . Detailed characterization involving XRD, TEM and TGA was investigated. The results show that The precipitation of magnesium oxalate from sea bittern is first order with respect to the concentration of magnesium oxalate at pH=4, MR=1:1 and temp.=25 °C Also, The rate constant doesn't strongly affected by increasing temperature so the optimum operating reaction temperature is 25 °C. The spherical Magnesium oxalate with uniform diameter of about 0.5 μm was o...
Magnesium gluconate was prepared as a medication product under ordinary conditions and is soluble... more Magnesium gluconate was prepared as a medication product under ordinary conditions and is soluble in water. Magnesia combine with both citric acid and gluconic acid as magnesium gluconate. The dry product mixed with a suitable amount of bicarbonate and heated under 300 oC is the equivalent in strength of magnesia solution and having a therapeutic effect. Analytical technique like, XRD, FTIR, UV Vis spectroscopy, TGA/ DTA and DSC were used to study properties of magnesium gluconate prepared. The product proved to be crystalline with wave length for maximum UV absorbance 197 nm. The DSC thermogram of the analyte indicated that product is stable up to 275 oC. Thus, it concludes that magnesium gluconate with crystal size 0.63-0.68 nm is a useful pharmaceutical and nutraceutical for industries. Besides when mixed with carbonate and heated up to 400 oC Periclase is produced as an essential product for different chemical industries.
Abstract Rice husk (RH) is produced in large quantities in Egypt and burned in open atmosphere to... more Abstract Rice husk (RH) is produced in large quantities in Egypt and burned in open atmosphere to produce RH ash (RHA), which poses a great risk to the environment by affecting the land and the surrounding areas in which it is disposed of. Consequently, this work is an attempt to prepare a modified sand/lime brick, employing a mixture of sand and different percentages of RHA (5%, 10%, and 15%) with 15% of burned calcite. The compressive strength and bulk density of the prepared sand bricks were determined. Further, the phase composition and structure of the surface of the samples were also identified by Fourier-transform infrared (FT–IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) techniques. It was confirmed that the modified sand/lime brick, composed of 80% sand, 5% RHA, and 15% lime, exhibited the best results. The obtained bulk density and compressive strength were 1.82 g/cm3 and 103 kg/cm2, respectively. A comparative estimation of the unit cost of the modified RHA–sand/lime brick and those of two other brick types, namely clay/RH and cement/RHA bricks, which had been prepared and reported by the authors, was performed. It was concluded that the partial replacement of RH, as solid agricultural waste, in the manufacture of building bricks can reduce the cost significantly, as 20% RH substitution (yielding 5% RHA) in the sand brick, 10% RH substitution in the clay brick, and also 20% RH substitution (yielding 5% RHA) in the cement brick, resulting in 14%, 42.8%, and 25% unit cost reductions, respectively.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Research Journal of Pharmaceutical, Biological and Chemical Sciences
Removal of nutrients such as ammonium and phosphate ions by natural or synthetic zeolite has been... more Removal of nutrients such as ammonium and phosphate ions by natural or synthetic zeolite has been studied on lab and pilot scales using an orbital shaker and mechanically stirred batch system respectively. Natural Zeolites are abundant and low cost resources. Due to their high cation-exchange ability as well as to the molecular sieve properties, natural zeolite has been widely used as adsorbents in separation and purification processes in post decades. The aim of the present study is to investigate adsorption and desorption behavior of Zeolite and activated carbon in removal of ammonium and phosphate from sewage wastewater (SWW). The lab scale was studied for the direct precipitation of struvite by adding bittern and crystallization of final product. On The pilot scale study the adsorbed/desorbed ammonium and phosphorous from 100 liter of (SWW) on Zeolite were precipitated by adding bittern as low cost source of magnesium ion. The Langmuir equation was fitted to the data points as 1...
Effect of gradually substitution of ordinary Portland cement by a few percent of silica fume (0.0... more Effect of gradually substitution of ordinary Portland cement by a few percent of silica fume (0.0, 2.5, 5.0 and 7.5 wt.%) on the durability of slag-Portland cement pastes up to 12 months immersed in sea water was investigated. The results show that the substitution of Portland cement by silica fume in the granulated slag-Portland cement pastes improves the physico-mechanical properties of the hardened cement pastes especially at early ages as well as gives a better resistance of cement stone to sea water attack at all immersing time. Also, the composite cement pastes containing 7.5% silica fume showed a maximum durability than other samples.
Investigations were carried out for making building bricks from Abu Zaabal altered basalt and de-... more Investigations were carried out for making building bricks from Abu Zaabal altered basalt and de-aluminated kaolin wastes. Samples were made from mixtures containing 90–70 % basalt and 10–30 % de-aluminated kaolin. Samples were prepared and dried at 105 °C as well as fired at different temperatures ranging from 900 to 1100 °C for 2 h soaking time. The physico-mechanical ceramic properties of the dried and fired samples were investigated. The study revealed that good quality bricks can be produced from 90–70 % basalt and 10–30 % de-aluminated kaolin.
The performance of UASB (Up-flow Anaerobic Sludge Blanket) reactor was investigated in the presen... more The performance of UASB (Up-flow Anaerobic Sludge Blanket) reactor was investigated in the present study for treatment of flax retting wastewater. Batch and continuous experiments on a pilot scale were designed. The initial seed for granules (bacteria acclimation) formed earlier was from municipal sewage treatment plant with VSS of 18-20 g/L. Batch experiments proved that the sludge retention time (SRT) was 77 days. Under steady state conditions, continuous experiments were conducted at organic loading rates (OLRs) in the range of 1.2 to 8.6 kg CODs m-3 •d-1 , where the hydraulic retention time (HRT) decreased from 72 to 12 hrs. The results proved that the UASB technology provides good COD removal efficiency from 64.5% to 90.5% as COD loading rate decreased and good biogas production at proper food: microorganism (F:M) ratios.
A mixture of different types of clay was blended with rice straw (RS) and microcrystalline cellul... more A mixture of different types of clay was blended with rice straw (RS) and microcrystalline cellulose (MCC) in the presence or absence of cement kiln dust (CKD) to produce new types of brick. The ratios of RS and MCC were 0, 5, and 10% w/w in the absence of CKD while they were kept at 5% w/w in its presence. The samples produced were compared to "blended" bricks prepared using 10% w/w CKD. Samples were fired at temperatures up to 1000 C and their surface and composition studied using SEM and XRD. Moreover, the chemical and physical properties of prepared bricks were determined. Introducing RS reduced both strength and bulk density but increased porosity of prepared samples. The presence of MCC alone increased the compressive strength, while combining RS with CKD overcame the decrease in strength resulting from the presence of RS alone. This has enabled the production of lightweight low-cost bricks with a compressive strength close to nonblended bricks, especially at high firing temperature.
Huge quantity of rice husk ash (RHA) and broken ceramics in Egypt are produced as wastes and beco... more Huge quantity of rice husk ash (RHA) and broken ceramics in Egypt are produced as wastes and become of great threat to the environment, causing damage to the land and the surrounding areas in which it is dumped. In addition, production of cement is responsible for about 7% of all CO2 generated in the world. For that, the aim of the present research is to produce modified cement bricks by replacing cement partially by RHA and broken ceramic wastes, to bring a substantial reduction for CO2 emitted every year in the atmosphere, and to reuse agricultural and industrial solid wastes. Therefore two sets of experiments were investigated by replacing part of Ordinary Portland Cement (OPC) with: 1) RHA and 2) mixture of RHA and ceramic wastes, to produce modified cement bricks, at different curing time, namely7,14 and 28 days. Characterizations of raw materials used for the target preparation were carried out covering: free silica and organic matters, XRD, TGA, and DTA. The cold and boiling ...
Open Journal of Chemical Engineering and Science, 2014
Anaerobic Digestion is a series of chemical reactions during which organic material is decomposed... more Anaerobic Digestion is a series of chemical reactions during which organic material is decomposed through the metabolic pathways of naturally occurring microorganisms in an oxygendepleted environment. In nature this type of breakdown typically occurs in warm wet and dark environments, such as in the digestive tracts. The microorganisms are exploited in the biotechnological process of anaerobic digestion both to reduce the pollution caused by organic wastes and to produce methane, which can be used as a fuel. The number and types of microorganisms present in digesters are likely to depend upon the type of digester, its operating conditions and the waste composition. Anaerobic Digesters can be used on any carbon containing industrial wastewater i.e. food processing; pulp and paper; sugar and distillery; slaughterhouse; cheese whey and diary units; brewing industry and municipal sludge. Also, they provide an effective method for turning residues from different wastes, biogas (rich in methane which can be used to generate heat and/or electricity); fiber (this can be used as a nutrient-rich soil conditioner) and liquor (this can be used as liquid fertilizer). In the review paper, the special emphasis on some of the environmental requirements; indicators of treatment unbalance; types of high rate anaerobic reactors; the application of anaerobic fermentation of selected high strength industrial wastewaters; modelling of anaerobic digestion, and finally, there is a case study.
The influence of substitution of Ordinary Portland cement by ground granulated blast-furnace slag... more The influence of substitution of Ordinary Portland cement by ground granulated blast-furnace slag up to 70% on the properties of silica fume-Portland cement composite pastes up to 12 months was studied. After one year, the composite cements pastes containing 50-70% slag exhibit suitable strength values compared to without slag sample. Also, XRD results show that the C-S-H are intensified with available increase indicating more dense structures and large amount of additional C-S-H in the presence slag content.
American Journal of Engineering and Applied Sciences, 2015
This work aimed to study the effect of the dosage of laboratory synthesized Sulfonated Acetone Fo... more This work aimed to study the effect of the dosage of laboratory synthesized Sulfonated Acetone Formaldehyde (SAF) on the physicmechanical characteristics and durability of SF-SRC cement pastes immersed in 4% MgCl 2 or 4% MgSO 4 solutions or at elevated temperatures up to 800°C. The compressive strength of thermally treatment cement pastes with 1.5% SAF increases up to 600°C, then decreases up to 800°C. Presence of 2.0% SAF works to produce a compact cementing structure, which decreases the accessibility of the penetration of chloride as well as sulphate ion penetration and enhances the durability, hence the total chloride and sulphate contents diminished.
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Papers by Randa Osman