Iron Filings Research Articles

Modeling of 2-chloronaphthalene interaction with high carbon iron filings (HCIF) in semi-batch and continuous systems.

Unrusted high carbon iron filings (HCIF) were contacted sequentially with successive aliquots of aqueous 2-chloronaphthalene (2-CN), i.e., in semi-batch mode, both in well-mixed and poorly-mixed conditions. Aqueous concentration of 2-CN and the dehalogenation by-product naphthalene (N) were monitored at the beginning and end of each 2-CN addition cycle. Experimental data was modeled using the 2-CN dehalogenation and adsorption/desorption rate constants determined from batch experiments involving 2-CN and a similar HCIF sample. Model predictions for the semi-batch experiments matched quite well with the experimental data in both well-mixed and poorly-mixed cases. Further, it was experimentally demonstrated that adsorption and hence accumulation of N on HCIF surface did not substantially hinder either 2-CN adsorption or dehalogenation under the conditions examined in this study. Continuous transport of water containing 0.5 μmol L(-1) 2-CN through a 1.0-m thick unrusted HCIF layer was simulated at superficial velocities of 0.01 and 0.10 m h(-1). Both simulations indicated nearly complete removal of 2-CN in the HCIF layer. This study suggests that HCIF can be used as a potential reactive material in permeable reactive barriers (PRBs) for in situ remediation of groundwater contaminated with 2-CN.

Radiation Shielding Characteristics of Concretes Incorporates Different Particle Sizes of Various Waste Materials

In this study, the dependence of gamma-ray absorption coefficient on the particulate matter sizes of steel slag, iron fillings and steel balls incorporated concrete were examined. The contents of these fillers in concrete mix was kept constant to 35 wt. %. Only the filler particle size was varied during the tests. The particle size ranged from 0.2mm to 1mm for steel slags and the iron fillings and from 2.5mm to 10mm for the steel balls.The concrete samples were assessed for their anti-radiation attenuation coefficient properties. The attenuation measurements were performed using gamma spectrometer of NaI (Tl) detector. The utilized radiation source was Cs137 radioactive element with photon energy of o.662 MeV. The results showed that gamma-ray attenuation coefficient was inversely proportional to the filler particulate matter size. Likewise the mean free paths for the tested samples were obtained. Maximum linear attenuation coefficient of 1.102±0.263cm-1 was attained for the iron filling.The iron balls and the steel slags showed much inferior values. The concrete incorporates iron filings afforded the best shielding effect. The density, microstructure, homogeneity and particulate distribution of the concrete samples were examined and evaluated using different metallographic, microscopic and measurement facilities.

Evaluation of mixtures of peat, zero-valent iron and alkalinity amendments for treatment of acid rock drainage

Reactive mixtures to be used in a permeable reactive barrier (PRB) for the treatment of low quality groundwater derived from a mine waste rock storage site were evaluated. Low pH drainage water from the site contained high concentrations of sulfate and dissolved metals, including Al, Co, Ni, and Zn. Column experiments were conducted to evaluate whether mixtures containing either peat moss (as an organic carbon source) or a mixture of peat moss and granular zero-valent iron (ZVI) filings, in addition to small amounts of lime and/or limestone, were suitable treatment materials for removing these metals from the water. The experimental results showed that the mixtures promote bacterially-mediated sulfate reduction and metal removal by precipitation of metal sulfides, metal carbonate/hydroxide precipitation, and adsorption under relatively high pH conditions (pH of 7–8). Both reactive mixtures removed influent dissolved metals to near or below the limit of detection in the effluent throughout the experiment; however, influent-level concentrations of the metals of interest gradually moved through the column containing peat alone, as the pH neutralizing ability in the mixture was consumed. In contrast, the column containing both peat and ZVI showed very little breakthrough of the influent metals, suggesting that the longevity of the mixture including ZVI will be much longer than the mixture containing peat alone. The results show that both reactive mixtures should be effective in a PRB installation as long as neutral pH conditions and microbial activity are maintained. The cost to performance ratio of the two reactive mixtures will be a key factor in determining which mixture is best suited for a particular site.

Mixed-Media Filter System for Removal of Multiple Contaminants from Urban Storm Water: Large-Scale Laboratory Testing

Urban storm water runoff consists of unacceptable levels of nutrients and heavy metals, and a mixed-media filter system is proposed to treat such storm water with multiple contaminants. In this study, a two-dimensional filter simulation test apparatus was constructed to examine the effectiveness of mixed media for the removal of multiple contaminants from synthetic storm water. The mixed media, selected based on several series of batch and column experiments in previous studies, consisted of a mixture of calcite, zeolite, sand, and iron filings. The mixed media was tested for removal of coexisting nitrate, phosphate, Ni, Cu, Cd, Cr, Pb, and Zn at concentrations and conditions relevant for typical urban storm water. Results show that the mixed-media filter was able to maintain high flow rates without any clogging issues, with an average hydraulic conductivity around 30 cm/min. No significant initial release or final desorption of the contaminants was observed. The filter system proved effective for the simultaneous removal of nutrients and heavy metals from the storm water, except for Ni, which had significantly lower removal efficiency than the other metals. Overall, the study indicated that a mixed-media filter can be designed with high contaminants removal capacity, but additional studies are recommended for evaluating long-term performance of the mixed-media filter under variable storm water field conditions.

Adsorption of mixtures of nutrients and heavy metals in simulated urban stormwater by different filter materials

In recent years, several best management practices have been developed for the removal of different types of pollutants from stormwater runoff that lead to effective stormwater management. Filter materials that remove a wide range of contaminants have great potential for extensive use in filtration systems. In this study, four filter materials (calcite, zeolite, sand, and iron filings) were investigated for their adsorption and efficiency in the removal of nutrients and heavy metals when they exist individually versus when they co-exist. Laboratory batch experiments were conducted separately under individual and mixed contaminants conditions at different initial concentrations. Adsorption capacities varied under the individual and mixed contaminant conditions due to different removal mechanisms. Most filter materials showed lower removal efficiency under mixed contaminant conditions. In general, iron filings were found effective in the removal of nutrients and heavy metals simultaneously to the maximum levels. Freundlich and Langmuir isotherms were used to model the batch adsorption results and the former better fitted the experimental results. Overall, the results indicate that the filter materials used in this study have the potential to be effective media for the treatment of nutrients and heavy metals commonly found in urban stormwater runoff.

Throwing Clay with Iron Fillings on the Potter's Wheel

Previous studies on Iron fillings and Clay have shown that Iron fillings is of significant importance in ceramic composite especially as it has to do with the reduction of shrinkage on clay and the speckle effect on clay for decorative ceramics wares. The working of Iron fillings of different aggregate sizes into clay is both a pleasant and ugly experience which is worthy of documenting. This will be important to guide a ceramist that will intend to line blend and produce wares with iron fillings and clay by throwing on the potter's wheel. Iron fillings were gotten and analysed by sieving into different aggregate sizes for experimentation on clay. Clays were also gotten and prepared into a workable consistency. Iron fillings and clay were blended together in different percentages, this was followed by throwing on the wheel. Just as iron fillings was differed in the clay, so also the effect it has on the throwing ability of the body as regard plasticity. If iron fillings is too much in the body, it becomes difficult and sometimes injurious to work on.

Removal of heavy metals from urban stormwater runoff using different filter materials

Heavy metals wash from tires, automobile exhausts, road asphalt, fuel combustion, parking dust, and recreational land into urban stormwater runoff and its subsequent discharge into surface and subsurface water sources can create public health and environmental hazards. An in-ground permeable reactive filter system is proposed to treat contaminated urban stormwater. However, the filter materials should be carefully selected. Several series of batch experiments were conducted with synthetic stormwater containing individual metal contaminants at different concentrations to determine the adsorption and removal behavior of four potential permeable inorganic filter materials (calcite, zeolite, sand, and iron filings) for six common toxic heavy metal contaminants (Cd, Cu, Pb, Ni, Cr, and Zn). The adsorbed metals, pH, oxidation–reduction potential and electrical conductivity of batch samples were determined. Isotherm modeling was performed to assess the mechanisms and quantify the adsorption of each filter material for the contaminants. The extent of adsorption and removal of metals was found to depend on the type and concentration of metal as well as the filter material. Langmuir or Freundlich isotherm proved best to describe the metal adsorption behavior. The maximum removal rates achieved for individual metals were: 95–100% Cd, Cu, Pb and Zn by calcite, zeolite and iron filings, 90% Ni by zeolite, and 100% Cr by iron filings. Sand produced low results with maximum levels of 8–58%. Based on the maximum adsorption capacity of each filter material, the typical filter size and volume of stormwater that can be treated were estimated. No single filter material was capable of removing all metals to the maximum extent; therefore, a combination of filter materials should be investigated for the simultaneous removal of multiple heavy metals.

Iron Filings as PRB Media Regression Analysis of Remediation of Chromium-Contaminated Groundwater

Regarding the iron filing as PRB padding media, this experiment researched the repair effect of iron filing to the groundwater polluted by Cr on condition that different initial concentration of Cr6+ and different flow velocity, and then with the help of the data regression analysis software SPSS、1stOpt、Excel etc, it studied the regression analysis of Cr6+ removal rate with the change of initial concentration and the flow velocity. The results indicated that: under the certain flow velocity, cubic polynomial is the best regression model of Cr6+ removal rate with the change of initial concentration;under the certain initial Cr6+ concentration, the change of Cr6+ removal rate with flow velocity can be fitted in the regression model of unitary linear well, and the decision coefficient R2of it can be up to above 0.9.

Radiation Shielding Characteristics of Concretes Incorporates Different Waste Materials

Samples of concrete incorporate different waste materials such as iron filings, iron balls of used ball bearings and slags from steel industry were assessed for their anti-radiation attenuation coefficient properties. The attenuation measurements were performed using gamma spectrometer of NaI (Tl) detector. The utilized radiation sources comprised Cs137and Co60radioactive elements with photon energies of o.662 MeV for Cs137and two1.17 and 1.33 MeV energy levels for the Co60. Likewise the mean free paths for the tested samples were obtained. The maximum linear attenuation coefficient values of 0.92±1.12×10-3for CS137and 1.12±1.57×10-3for CO60attained, in this study were for concrete incorporate iron filling wastes of 30 wt. %. The iron balls and the steel slags gave much inferior values. The concrete incorporates iron filings provided the best shielding effect. The microstructure, concretefillings composite density, the homogeneity and particulate distribution were examined and evaluated using different metallographic, microscopic and measurement facilities.

Nutrients Removal from Urban Stormwater by Different Filter Materials

Urban stormwater runoff is contaminated by nutrients that wash off of roadways, parking lots and lawns during storms. In-ground permeable filter systems that consist of carefully selected filter material have the potential to remove these nutrients from the run-off. In this paper, four filter materials, calcite, zeolite, sand and iron filings, were investigated using laboratory batch tests to evaluate their efficiency in the removal of nitrate and phosphate from the simulated stormwater at different initial concentrations under the same 24-h exposure time period. The range of removal for nitrate was from 39 % to 65 % for calcite, from 42 % to 77 % for zeolite, from 40 % to 70 % for sand, and from 74 % to 100 % for iron filings. The removal of phosphate ranged from 35 % to 41 % for calcite, 59 % to 100 % for zeolite, 49 % to 100 % for sand, and 73 % to 100 % for iron filings. The removal of nitrate is mainly attributed to electrostatic adsorption, except when iron filings were used as a filter material where additional processes such as electrochemical reduction, ligand complexation and precipitation may have contributed to the higher nitrate removal. Phosphate removal is also attributed to electrostatic adsorption in all filter materials; however, at higher phosphate concentrations, the precipitation process may be the dominant process for all of the filter materials except calcite. The Langmuir and Freundlich isotherms fitted the observed nonlinear adsorption results, but the mechanism of removal of phosphate changed from adsorption to precipitation at concentrations higher than 1 mg/l in zeolite, sand, and iron filings; therefore, the adsorption models are valid below this concentration limit. A typical application of these batch adsorption test results is presented in the design of a field in-ground permeable filter system.

High genotoxicity of shipyard contaminants on Allium cepa and calf thymus DNA

Water pollution is a major environmental problem worldwide. In particular, shipyards are contaminating waters with iron, lead and copper filings, paints, petrochemical products and solvents. There are only a few reports on the genotoxicity of shipyard contaminants. Here, we study genotoxic effects of surface water from five sites of Hooghly River in West Bengal, India, along the banks of which many shipbuilding and scrap industries are located. Genotoxicity was measured by the detection of micronuclei in Allium cepa and other chromosomal aberrations, as well as damage to genomic DNA of calf thymus. Results show that A. cepa roots treated with contaminated water induced morphological distortions, formation of micronuclei and various types of chromosomal aberrations. The mitotic index was lower than 50 % in the treated samples. The breakage of calf thymus DNA was time-dependent with acute damage of 100 % for overnight incubation as evidenced by agarose gel electrophoresis. We conclude that the workers of local shipbuilding and scrap industries, the residents of nearby areas and the aquatic biodiversity are vulnerable to contaminated waters.

PAHs Removal from Urban Storm Water Runoff by Different Filter Materials

AbstractUrban storm water runoff is contaminated as deleterious materials wash from roadways, parking lots, and open spaces, and the subsequent discharge into surface water sources, such as lakes, can pose adverse effects on public health and the environment. Oil leaks and spills on roadways and parking lots can contain toxic polycyclic aromatic hydrocarbons (PAHs) that can be washed by storm water runoff. Although many best management practices have been developed to treat urban storm water, in-ground filter systems can be best suited in urban site-constrained settings. This paper investigates the effectiveness of different permeable inorganic materials as filter media for the removal of PAHs from storm water runoff. Several series of batch experiments were conducted using four different filter media (calcite, zeolite, sand, and iron filings) and synthetic storm water containing representative PAHs (naphthalene or phenanthrene) at different initial concentrations. The PAH removal and system chemistry in ...

Iron Filings as PRB Media Binary Regression Analysis of Remediation of Chromium-Contaminated Groundwater

Regarding the iron filing as PRB padding media, this experiment researched the repair effect of iron filing to the groundwater polluted by Cr+6on condition that different initial concentration of Cr6+and different flow velocity, and then with the help of the data regression analysis software SPSS1stOptExcel etc, it studied the regression analysis of Cr6+removal rate with binary linear and binary nonlinear of the initial concentration and the flow velocity. The results indicated that: the change process of Cr6+removal rate with initial concentration and flow velocity can adopt regression model analysis of binary linear and binary nonlinear, and in this test, the decision coefficient of the regression model of binary linear (0.825) was smaller than the decision coefficient R2of binary nonlinear (0.955), which illustrated, comparing with the regression model of binary linear, the one of binary nonlinear z=(p1+p3*x+p5*Ln (y)+p7*x^2+p9*(Ln (y))^2+p11*x *Ln (y))/(1+p2*x+p4*Ln (y)+p6*x^2+p8*(Ln (y))^2+p10*x*Ln (y)) can simulate the change trend of Cr6+removal rate with initial concentration and flow velocity better.

The Effect of Various Waste Materials' Contents on the Attenuation Level of Anti-Radiation Shielding Concrete.

Samples of concrete contain various waste materials, such as iron particulates, steel balls of used ball bearings and slags from steel industry were assessed for their anti-radiation attenuation coefficient properties. The attenuation measurements were performed using gamma spectrometer of NaI (Tl) detector. The utilized radiation sources comprised 137Cs and 60Co radioactive elements with photon energies of 0.662 MeV for 137Cs and two energy levels of 1.17 and 1.33 MeV for the 60Co. Likewise the mean free paths for the tested samples were obtained. The aim of this work is to investigate the effect of the waste loading rates and the particulate dispersive manner within the concrete matrix on the attenuation coefficients. The maximum linear attenuation coefficient (μ) was attained for concrete incorporates iron filling wastes of 30 wt %. They were of 1.12 ± 1.31×10−3 for 137Cs and 0.92 ± 1.57 × 10−3 for 60Co. Substantial improvement in attenuation performance by 20%–25% was achieved for concrete samples incorporate iron fillings as opposed to that of steel ball samples at different (5%–30%) loading rates. The steel balls and the steel slags gave much inferior values. The microstructure, concrete-metal composite density, the homogeneity and particulate dispersion were examined and evaluated using different metallographic, microscopic and measurement facilities.

Removal of As from groundwater by in situ bioprecipitation and zero-valent iron

The aim of this study was to evaluate the in situ bioprecipitation (ISBP) and zero-valent iron (ZVI) for removal of arsenic from groundwater. Batch experiments were set up to test the metal/oxyanion removal efficiency using the processes induced by ZVI, by ISBP and by combining both technologies. For the construction of microcosms in anaerobic condition, aquifer material was mixed with synthetic groundwater in serum bottles. Solutions that contained commercial iron (powder, filings), iron from foundry (chips) and lactate with the carbon concentration of 0.02% (w/v) were amended. After 57 days the pH increased to 7.9 in the microcosm with lactate + iron chips. In the microcosms amended with lactate + commercial iron (powder and filings), pH was between 6.9 and 7.5 The highest decrease in sulfate concentrations was observed in the microcosm supplied with lactate (from 1,976 to 630 mg/L), and with lactate + iron filings (from 1,985 to 1,280 mg/L). The results showed that ISBP and ZVI can be efficient in the removal of As from groundwater; however, it strongly depends on the type and particle size of ZVI. The most effective was commercial ZVI. The highest decrease in As concentration was observed in the microcosm supplied with ethanol and iron powder (from 4,832 to 131 μg/L).

DEGRADATION OF MONO-AZO DYE IN AQUEOUS SOLUTION USING CAST IRON FILINGS

The mono-azo dye, Orange II, solution was substanti ally degraded with cast iron particles under varied conditions of experimental variables such as pH, initial dye concentration and cast iron dosage.At all solution pH studied, the d egradation efficiency achieved was > 90%. With an initial dye concentration of 100 mg/L and optimum cast iron load of 28.56 g/L, the optimum degradation efficiency of 97.63% was achieved at pH 3. With sam e cast iron load and solution pH, more than 95% dye degradation efficiency was achieved at different initial Orange II concentrati ons ranging from 50-500 mg/L. The efficiency of cas t iron particles in degrading Orange II dye was compared with that of pure elemen tal iron used in other study. Cast iron particles showed better degradation efficiencies than elemental iron that too at relatively lower dosages. Ultimately, from the results it can be inferred that cast iron fillings can be successfully applied to treat textile effluents containing high dye concentration and treatment efficiency can be enhanced by optimizing the reaction conditions.

Effect of the Addition of Zero Valent Iron (Fe0) on the Batch Biological Sulphate Reduction Using Grass Cellulose as Carbon Source

Mineral mining generates acidic, saline, metal-rich mine waters, often referred to as acid mine drainage (AMD). Treatment of AMD and recovering saleable products during the treatment process are a necessity since water is, especially in South Africa, a scarce commodity. The aim of the study presented here was to investigate the effect of zero valent iron (Fe(0)) on the biological removal of sulphate from AMD in batch reactors. The performance of the reactors was assessed by means of sulphate reduction, chemical oxygen demand (COD), volatile fatty acid (VFA) utilisation and volatile suspended solids (VSS) concentration. To this end, three batch reactors, A, B and C (volume 2.5 L), were operated similarly with the exception of the addition of grass cuttings and iron filings. Reactors A and B received twice as much grass (100 g) as C (50 g). Reactor A received no iron filings to act as a control, while reactors B and C received 50-g iron filings for the experimental duration. The results showed that Fe(0) appears to provide sustained sulphate removal when sufficient grass substrate is available. In reactors A and C, sulphate removal efficiency was higher when the COD concentration was lower due to utilisation. In reactor B, sulphate removal efficiency was accompanied by an accumulation of COD as hydrogen (H2) provided by the Fe(0) was utilised for sulphate reduction. Furthermore, these results showed the potential of Fe(0) to enhance the participation of microorganisms in sulphate reduction.

The Effect of Iron Fillings Waste Contents on the Attenuation Level of Anti-Radiation Shielding Concrete

Shielding concretes of different iron filling contents were assessed for their anti radiation attenuation properties. The measurements have been performed by using gamma spectrometer of NaI (Tl) detector, the sources were Cs137 and Co60 radioactive elements with photon energies of o.662 MeV, for Cs137 and the two 1.17MeV, 1.33 MeV energy levels for the Co60. Likewise, the mean free path of the tested samples was obtained as well. From the measurement of the linear attenuation coefficients for these different shielding materials, it was found that as the iron filings within the concrete are increased the linear attenuation coefficient is increased also. It can be concluded from this work that the Iron filings content in concrete is very effective in augmentation of the anti-radiation shielding capability. It can be used as shelters material for secure storing of the nuclear wastes.

Production of hydrogen and syngas via pyrolysis of bagasse in a dual bed reactor

Pyrolysis of bagasse followed by thermal cracking of tar was carried out at atmospheric pressure using a dual bed reactor. The first bed was used for the pyrolysis and the second bed was used for thermal cracking of tar. Iron fillings were used as the packed bed material in the second bed. The effects of reaction time (20 to 40 min), reactor temperature (600 to 900 °C) and packed bed height (40–100 mm) on the product (char, tar and gas) yield and gas (H2, CO, CO2, CH4, CnHm) composition were studied. Over the ranges of the experimental conditions used, the operating conditions were optimized for pyrolysis temperature around 850 °C, a reaction time of 30 min and packed bed height of 100 mm, thus we could obtain a gas richer in hydrogen and carbon monoxide and poorer in carbon dioxide and hydrocarbons. It was observed that compared with single bed process, dual bed process increased the gas yield from 0.397 to 0.750 m3/kg and decreased the tar yield from 0.445 to 0.268 g/g while the heating value of the product gas remained almost constant (10–11 MJ/m3).

Pretreatment of petroleum refinery wastewater by microwave-enhanced Fe0/GAC micro-electrolysis

The pretreatment of petroleum refinery wastewater (PRW) was experimentally investigated using the Fe0/granular activated carbon (GAC) micro-electrolysis system in the absence or presence of microwave. Effects of reaction time, pH value, Fe0 and GAC dosage, Fe0/GAC volumetric ratio, and microwave power on the treatment efficiency of wastewater were studied. A significant synergetic effect was observed between microwave irradiation and Fe0/GAC. The optimum conditions were determined to be: microwave power 500 W, reaction time 15 min, iron filings dosage 30 g/L, GAC dosage 5.75 g/L, and initial pH 3. Under the optimum conditions, chemical oxygen demand (COD) removal efficiencies were 38.3 and 62.2% in the absence and presence of microwave irradiation, respectively. The biodegradability of the wastewater was greatly improved by the microwave enhanced micro-electrolysis treatment. The results of the present study demonstrated that the pretreatment process was favorable for the subsequent biological process.