Search results for: heavy mineral
Commenced in January 2007
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Edition: International
Paper Count: 2308

Search results for: heavy mineral

2068 Assessment of Heavy Metal Contamination in Soil and Groundwater Due to Leachate Migration from an Open Dumping Site

Authors: Kali Prasad Sarma

Abstract:

Indiscriminate disposal of municipal solid waste (MSW) in open dumping site is a common scenario in developing countries like India which poses a risk to the environment as well as human health. The objective of the present investigation was to find out the concentration of heavy metals (Pb, Cr, Ni, Mn, Zn, Cu, and Cd) and other physicochemical parameters of leachate and soil collected from an open dumping site of Tezpur town, Assam, India and its associated potential ecological risk. Tezpur is an urban agglomeration coming under the category of Class I UAs/Towns with a population of 105,377 as per data released by Government of India for Census 2011. Impact of the leachate on the groundwater was also addressed in our study. The concentrations of heavy metals were determined using ICP-OES. Energy dispersive X-Ray (SEM-EDS) microanalysis was also conducted to see the presence of the studied metals in the soil. X-Ray diffraction analysis (XRD) and Fourier Transform Infrared (FTIR) spectroscopy were also used to identify dominant minerals present in the soil samples. The trend of measured heavy metals in the soil samples was found in the following order: Mn > Pb > Cu > Zn > Cr > Ni > Cd. The assessment of heavy metal contamination in the soil was carried out by calculating enrichment factor (EF), geo-accumulation index (Igeo), contamination factor (Cfi), degree of contamination (Cd), pollution load index (PLI) and ecological risk factor (Eri). The study showed that the concentrations of Pb, Cu, and Cd were much higher than their respective average shale value and the EF of the soil samples depicted very severe enrichment for Pb, Cu, and Cd; moderate enrichment for Cr and Zn. Calculated Igeo values indicated that the soil is moderate to strongly contaminated with Pb and uncontaminated to moderately contaminated with Cd and Cu. The Cfi value for Pb indicates a very strong contamination level of the metal in the soil. The Cfi values for Cu and Cd were 2.37 and 1.65 respectively indicating moderate contamination level. To apportion the possible sources of heavy metal contamination in soil, principal components analysis (PCA) has been adopted. From the leachate, heavy metals are accumulated at the dumping site soil which could easily percolate through the soil and reach the groundwater. The possible relation of groundwater contamination due to leachate percolation was examined by analyzing the heavy metal concentrations in groundwater with respect to distance from the dumping site. The concentrations of Cd and Pb in groundwater (at a distance of 20m from dumping site) exceeded the permissible limit for drinking water as set by WHO. Occurrence of elevated concentration of potentially toxic heavy metals such as Pb and Cd in groundwater and soil are much environmental concern as it is detrimental to human health and ecosystem.

Keywords: groundwater, heavy metal contamination, leachate, open dumping site

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2067 Natural Radioactivity in Tunisian Bottled Mineral Waters

Authors: Salam Labidi, Sonia Machraoui, Souha Gharbi

Abstract:

Radium isotopes (226Ra, 228Ra) and uranium isotopes (234U, 238U) activity concentrations were determined in most popular Tunisian bottled mineral waters samples. Activity concentrations of uranium were studied by radiochemical separation procedures followed by alpha spectrometry and that of radium isotopes by gamma-ray spectrometry. The activity concentrations of 238U, 234U, 226Ra and 228Ra in water samples varied in range 3.3 - 22.5 mBq.L−1, 4.0 - 34.2 mBq L−1, 2.0 - 67.0 mBq L−1 and 2.0 - 30.2 mBq L−1, respectively. These values are comparable with those reported for many other countries in the world for different types of water. Based on the activity concentration results obtained in this study, the estimated annual ingestion dose rates for three different age groups (babies, children and adults) due to the ingestion of radium and uranium isotopes through drinking water are lower than the limit of intake prescribed by WHO. The annual doses exceed the recommended value of 0.1 mSv y-1 in one case for babies.

Keywords: mineral water, natural radioactivity, radiation dose, radium, uranium

Procedia PDF Downloads 239
2066 Impact of Anthropogenic Activities on Soil Quality Using the Land Snail Cantareus apertus as Bioindicator of Heavy Metals Accumulation in The Bejaia Region (Northeastern Algeria)

Authors: Benbelil-Tafoughalt Saida, Tababouchet Meriem

Abstract:

The main goal of this study was to investigate the impact of anthropogenic activities on soil quality using the land snail Cantareusapertus as a bioindicator of heavy metal accumulation. Concentrations of cadmium, copper, and zinc were measured in various body organs, viz: viscera and foot of the land snail Cantareusapertus. The snails were collected from two different sites in the Bejaia region (Northeastern Algeria), exposed to different sources of contamination by trace metals. The first sampling site is an urban areas, and the second is characterized by heavy industry, a potential source of soil pollution via heavy metal contamination. The concentrations of heavy metal in all viscera and foot samples were measured using an atomic absorption spectrophotometer. Bioconcentration of the trace metals Cu, Zn, and Cd varied between the viscera and the foot with the viscera having the highest concentration (µgg-1) of all metals than the foots; Cu, 2.03 – 5.8 (Viscera), 0.05 – 3.30 (Foot), Zn, 23.64 – 45.02 (Viscera), 1.87 – 15.15 (Foot) and Cd, 0.36 – 15.26 (Viscera), 0.18 – 13.73 (Foot), which suggest that ingestion may be the main uptake route of these essential metals. On the other hand, the levels of heavy metals varied significantly among the sampling area (P<0.001). in fact, in the foots as well as in the viscera, the concentrations of all studied metals is significantly higher in the snails sampled from sites closest to potential sources of pollution compared to those collected from urban areas characterized by moderate pollution.

Keywords: anthropogenic activities, Bioconcentration, Cantareus apertus, trace metals

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2065 Chemical Pollution of Water: Waste Water, Sewage Water, and Pollutant Water

Authors: Nabiyeva Jamala

Abstract:

We divide water into drinking, mineral, industrial, technical and thermal-energetic types according to its use and purpose. Drinking water must comply with sanitary requirements and norms according to organoleptic devices and physical and chemical properties. Mineral water - must comply with the norms due to some components having therapeutic properties. Industrial water must fulfill its normative requirements by being used in the industrial field. Technical water should be suitable for use in the field of agriculture, household, and irrigation, and the normative requirements should be met. Heat-energy water is used in the national economy, and it consists of thermal and energy water. Water is a filter-accumulator of all types of pollutants entering the environment. This is explained by the fact that it has the property of dissolving compounds of mineral and gaseous water and regular water circulation. Environmentally clean, pure, non-toxic water is vital for the normal life activity of humans, animals and other living beings. Chemical pollutants enter water basins mainly with wastewater from non-ferrous and ferrous metallurgy, oil, gas, chemical, stone, coal, pulp and paper and forest materials processing industries and make them unusable. Wastewater from the chemical, electric power, woodworking and machine-building industries plays a huge role in the pollution of water sources. Chlorine compounds, phenols, and chloride-containing substances have a strong lethal-toxic effect on organisms when mixed with water. Heavy metals - lead, cadmium, mercury, nickel, copper, selenium, chromium, tin, etc. water mixed with ingredients cause poisoning in humans, animals and other living beings. Thus, the mixing of selenium with water causes liver diseases in people, the mixing of mercury with the nervous system, and the mixing of cadmium with kidney diseases. Pollution of the World's ocean waters and other water basins with oil and oil products is one of the most dangerous environmental problems facing humanity today. So, mixing even the smallest amount of oil and its products in drinking water gives it a bad, unpleasant smell. Mixing one ton of oil with water creates a special layer that covers the water surface in an area of 2.6 km2. As a result, the flood of light, photosynthesis and oxygen supply of water is getting weak and there is a great danger to the lives of living beings.

Keywords: chemical pollutants, wastewater, SSAM, polyacrylamide

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2064 Trace Metals in Natural Bottled Water on Montenegrin Market and Comaparison with Tap Water in Podgorica

Authors: Katarina Živković, Ivana Joksimović

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Many different chemicals may occur in drinking water and cause significant human health risks after prolonged periods of exposure. In particular concern are contaminants that have cumulative toxic properties, such as heavy metals. This investigation was done to clarify concerns about chemical quality and safety of drinking tap water in Podgorica. For comparison, all available natural bottled water on Montenegrin market were bought. All samples (bottled water and tap water from Podgorica) were analyzed using ICP –OES on contents of Al, Cd, Pb, Cu, Zn,Cr, Fe, As and Mn. All results compared with the maximum concentration levels allowed by international standards and World Health Organization (WHO) guidelines. The results of analysis showed that all trace of heavy metals were very low and in same time below MCL according to WHO and International standard.

Keywords: inductively coupled plasma - optical emission spectrometry (ICP-OES), Montenegro (Podgorica), natural bottled water, tap water , trace of heavy metal

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2063 The Impact on the Network Deflectometry

Authors: Djamel–Eddine Yassine Boutiba

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In this present memory, we present the various impacts deflectometer leading to the sizing by strengthening of existing roadways. It reminds that the road network in Algeria plays a major role with regard to drainage in major strategic areas and especially in the fringe northern Algeria. Heavy traffic passing through the northern fringe (between 25% and 30% heavy vehicles) causes substantial degradations at both the surface layer and base layer. The work on site by means within the laboratory CTTP such as deflectographe Lacroix, allowed us to record a large number of deflection localized bending on RN19A (Carrefour CW73-Ain- Merane), whose analysis of the results led us to opt for a building throughout the band's project . By the recorder against HWD (Heavy Weight déflectometer) allowed us to learn about the behavior of the pavement on the banks. In addition, the Software Alize III has been essential in the verification of the increase in the thickness dimensioned.

Keywords: capacity, deflection, deflectograph lacroix, degradation, hwd

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2062 Chemometric-Based Voltammetric Method for Analysis of Vitamins and Heavy Metals in Honey Samples

Authors: Marwa A. A. Ragab, Amira F. El-Yazbi, Amr El-Hawiet

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The analysis of heavy metals in honey samples is crucial. When found in honey, they denote environmental pollution. Some of these heavy metals as lead either present at low or high concentrations are considered to be toxic. Other heavy metals, for example, copper and zinc, if present at low concentrations, they considered safe even vital minerals. On the contrary, if they present at high concentrations, they are toxic. Their voltammetric determination in honey represents a challenge due to the presence of other electro-active components as vitamins, which may overlap with the peaks of the metal, hindering their accurate and precise determination. The simultaneous analysis of some vitamins: nicotinic acid (B3) and riboflavin (B2), and heavy metals: lead, cadmium, and zinc, in honey samples, was addressed. The analysis was done in 0.1 M Potassium Chloride (KCl) using a hanging mercury drop electrode (HMDE), followed by chemometric manipulation of the voltammetric data using the derivative method. Then the derivative data were convoluted using discrete Fourier functions. The proposed method allowed the simultaneous analysis of vitamins and metals though their varied responses and sensitivities. Although their peaks were overlapped, the proposed chemometric method allowed their accurate and precise analysis. After the chemometric treatment of the data, metals were successfully quantified at low levels in the presence of vitamins (1: 2000). The heavy metals limit of detection (LOD) values after the chemometric treatment of data decreased by more than 60% than those obtained from the direct voltammetric method. The method applicability was tested by analyzing the selected metals and vitamins in real honey samples obtained from different botanical origins.

Keywords: chemometrics, overlapped voltammetric peaks, derivative and convoluted derivative methods, metals and vitamins

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2061 Analysis of Long-Term Response of Seawater to Change in CO₂, Heavy Metals and Nutrients Concentrations

Authors: Igor Povar, Catherine Goyet

Abstract:

The seawater is subject to multiple external stressors (ES) including rising atmospheric CO2 and ocean acidification, global warming, atmospheric deposition of pollutants and eutrophication, which deeply alter its chemistry, often on a global scale and, in some cases, at the degree significantly exceeding that in the historical and recent geological verification. In ocean systems the micro- and macronutrients, heavy metals, phosphor- and nitrogen-containing components exist in different forms depending on the concentrations of various other species, organic matter, the types of minerals, the pH etc. The major limitation to assessing more strictly the ES to oceans, such as pollutants (atmospheric greenhouse gas, heavy metals, nutrients as nitrates and phosphates) is the lack of theoretical approach which could predict the ocean resistance to multiple external stressors. In order to assess the abovementioned ES, the research has applied and developed the buffer theory approach and theoretical expressions of the formal chemical thermodynamics to ocean systems, as heterogeneous aqueous systems. The thermodynamic expressions of complex chemical equilibria, involving acid-base, complex formation and mineral ones have been deduced. This thermodynamic approach utilizes thermodynamic relationships coupled with original mass balance constraints, where the solid phases are explicitly expressed. The ocean sensitivity to different external stressors and changes in driving factors are considered in terms of derived buffering capacities or buffer factors for heterogeneous systems. Our investigations have proved that the heterogeneous aqueous systems, as ocean and seas are, manifest their buffer properties towards all their components, not only to pH, as it has been known so far, for example in respect to carbon dioxide, carbonates, phosphates, Ca2+, Mg2+, heavy metal ions etc. The derived expressions make possible to attribute changes in chemical ocean composition to different pollutants. These expressions are also useful for improving the current atmosphere-ocean-marine biogeochemistry models. The major research questions, to which the research responds, are: (i.) What kind of contamination is the most harmful for Future Ocean? (ii.) What are chemical heterogeneous processes of the heavy metal release from sediments and minerals and its impact to the ocean buffer action? (iii.) What will be the long-term response of the coastal ocean to the oceanic uptake of anthropogenic pollutants? (iv.) How will change the ocean resistance in terms of future chemical complex processes and buffer capacities and its response to external (anthropogenic) perturbations? The ocean buffer capacities towards its main components are recommended as parameters that should be included in determining the most important ocean factors which define the response of ocean environment at the technogenic loads increasing. The deduced thermodynamic expressions are valid for any combination of chemical composition, or any of the species contributing to the total concentration, as independent state variable.

Keywords: atmospheric greenhouse gas, chemical thermodynamics, external stressors, pollutants, seawater

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2060 Development of Environmentally Clean Construction Materials Using Industrial Waste from Kazakhstan

Authors: Galiya Zhanzakovna Alzhanova, Yelaman Kanatovich Aibuldinov, Zhanar Baktybaevna Iskakova, Gaziz Galymovich Abdiyussupov, Madi Toktasynuly Omirzak, Aizhan Doldashevna Gazizova

Abstract:

The sustainable use of industrial waste has recently increased due to increased environmental problems in landfills. One of the best ways to utilise waste is as a road base material. Industrial waste is a less costly and more efficient way to strengthen local soils than by introducing new additive materials. This study explored the feasibility of utilising red mud, blast furnace slag, and lime production waste to develop environmentally friendly construction materials for stabilising natural loam. Four different ratios of red mud (20, 30, and 40%), blast furnace slag (25, 30, and 35%), lime production waste (4, 6, and 8%), and varied amounts of natural loam were combined to produce nine different mixtures. The results showed that the sample with 40% red mud, 35% blast furnace slag, and 8% lime production waste had the highest strength. The sample's measured compressive strength for 90 days was 7.38 MPa, its water resistance for the same period was 7.12 MPa, and its frost resistance for the same period was 7.35 MP; low linear expansion met the requirements of the Kazakh regulations for first-class building materials. The study of mineral composition showed that there was no contamination with heavy metals or dangerous substances. Road base materials made of red mud, blast furnace slag, lime production waste, and natural loam mix can be employed because of their durability and environmental performance. The chemical and mineral composition of raw materials was determined using X-ray diffraction, X-ray fluorescence, scanning electron microscopy, energy dispersive spectroscopy, atomic absorption spectroscopy, and axial compressive strength were examined.

Keywords: blast furnace slag, lime production waste, natural loam stabilizing, red mud, road base material

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2059 Determination of Physicochemical Properties, Bioaccessibility of Phenolics and Antioxidant Capacity of Mineral Enriched Linden Herbal Tea Beverage

Authors: Senem Suna, Canan Ece Tamer, Ömer Utku Çopur

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In this research, dried linden (Tilia argentea) leaves and blossoms were used as a raw material for mineral enriched herbal tea beverage production. For this aim, %1 dried linden was infused with boiling water (100 °C) for 5 minutes. After cooling, sucrose, citric acid, ascorbic acid, natural lemon flavor and natural mineral water were added. Beverage samples were plate filtered, filled into 200-mL glass bottles, capped then pasteurized at 98 °C for 15 minutes. Water soluble dry matter, titratable acidity, ascorbic acid, pH, minerals (Fe, Ca, Mg, K, Na), color (L*, a*, b*), turbidity, bioaccessible phenolics and antioxidant capacity were analyzed. Water soluble dry matter, titratable acidity, and ascorbic were determined as 7.66±0.28 g/100 g, 0.13±0.00 g/100 mL, and 19.42±0.62 mg/100 mL, respectively. pH was measured as 3.69. Fe, Ca, Mg, K and Na contents of the beverage were determined as 0.12±0.00, 115.48±0.05, 34.72±0.14, 48.67±0.43 and 85.72±1.01 mg/L, respectively. Color was measured as 13.63±0.05, -4.33±0.05, and 3.06±0.05 for L*, a*, and b* values. Turbidity was determined as 0.69±0.07 NTU. Bioaccessible phenolics were determined as 312.82±5.91 mg GAE/100 mL. Antioxidant capacities of chemical (MetOH:H2O:HCl) and physiological extracts (in vitro digestive enzymatic extraction) with DPPH (27.59±0.53 and 0.17±0.02 μmol trolox/mL), FRAP (21.01±0.97 and 13.27±0.19 μmol trolox/mL) and CUPRAC (44.71±9.42 and 2.80±0.64 μmol trolox/mL) methods were also evaluated. As a result, enrichment with natural mineral water was proposed for the development of functional and nutritional values together with a good potential for commercialization.

Keywords: linden, herbal tea beverage, bioaccessibility, antioxidant capacity

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2058 Effect of Mineral Admixtures on Transport Properties of SCCs Composites: Influence of Mechanical Damage

Authors: Davood Niknezhad, Siham Kamali-Bernard

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Concrete durability is one of the most important considerations in the design of new structures in aggressive environments. It is now common knowledge that the transport properties of a concrete, i.e; permeability and chloride diffusion coefficient are important indicators of its durability. The development of microcracking in concrete structures leads to significant permeability and to durability problems as a result. The main objective of the study presented in this paper is to investigate the influence of mineral admixtures and impact of compressive cracks by mechanical uniaxial compression up to 80% of the ultimate strength on transport properties of self-compacting concrete (SCC) manufactured with the eco-materials (metakaolin, fly ash, slag HF). The chloride resistance and binding capacity of the different SCCs produced with the different admixtures in damaged and undamaged state are measured using a chloride migration test accelerated by an external applied electrical field. Intrinsic permeability is measured using the helium gas and one permeameter at constant load. Klinkenberg approach is used for the determination of the intrinsic permeability. Based on the findings of this study, the use of mineral admixtures increases the resistance of SCC to chloride ingress and reduces their permeability. From the impact of mechanical damage, we show that the Gas permeability is more sensitive of concrete damaged than chloride diffusion. A correlation is obtained between the intrinsic permeability and chloride migration coefficient according to the damage variable for the four studied mixtures.

Keywords: SCC, concrete durability, transport properties, gas permeability, chloride diffusion, mechanical damage, mineral admixtures

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2057 Determination of Heavy Metals (Cd, Pb, Hg, Cu, Fe, Mn, Al, As, Ni and Zn) in 6 Important Commercial Fish Species in North of Hormoz Strait

Authors: Majid Afkhami, Maryam Ehsanpour, Zahra Khoshnood

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The concentrations of 10 heavy metals (Cd, Pb, Hg, Cu, Fe, Mn, Al, As, Ni, Zn) were measured in muscle, gill and liver of 6 species from Hormoz Strait in north coast of Persian Gulf in 12 months (April 2009 – March 2010). All samples were analyzed three times for Cd, Pb, Cu, Fe, Mn, Al, As, Ni, Zn by inductively coupled plasma-atomic emission spectrometry (ICP-AES) and for Hg by LECO AMA254 Advanced Mercury Analyzer. Results of this study showed that iron had the highest concentration (total mean concentration) in all species, followed by Zn, Cu, Ni, Al, Pb, Mn, Cd, Hg and lowest concentration in three tissues was As. In addition, the accumulation of metals was species-dependent, and was higher in Scomberomorous commerson and Scomberomorous guttatus (p<0.05) and the lowest concentration was record in Pampus argenteus (p<0.05).

Keywords: Persian Gulf, heavy metals, Hormoz strait, Scomberomorous guttatus, Scomberomorous commerson, Pampus argenteus

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2056 Microalgae as Promising Biostimulants of Plant Tolerance Against Heavy Metals

Authors: Soufiane Fal, Abderahim Aasfar, Ali Ouhssain, Hasnae Choukri, Abelaziz Smouni, Hicham El Arroussi

Abstract:

Heavy metals contamination is a major environmental concern around the world. It has a harmful impact on plant productivity and poses a serious risk to humans and animals health. In the present study, the effect of Microalgae Crude Extract (MCE) on tomato growth and nutrients uptake exposed to 2 mM Pb2+ and Cd2+ was investigated. In results, 2 mM Pb2+ and Cd2+ showed a significant reduction of tomatobiomass and perturbation in nutrients absorption. Moreover, MCE application in tomato plant exposed to Pb2+ and Cd2+ showed a significant enhancement of biomass compared to tomato plants under Pb2+ and Cd2+. On the other hand, MCE application favoured heavy metals accumulation in root and inhibited their translocation to shoot as phytostabilisation mechanism. Tomato plants showed biochemical responses to Pb2+ and Cd2+ stress with elevation of scavenging enzymes and molecules such as POD, CAT, SOD, Proline, and polyphenols, etc. In addition, the treatment by MCE showed a significant reduction level of the majority of these parameters. Furthermore, the metabolomic analysis revealed a significant change in important metabolites. Pb2+ and Cd2+ showed decrease in SFA and increase of UFA, VLFA, alkanes, alkenes, sterols, which known accumulated as tolerance and resistance mechanism to heavy metal (H.M) stress. However, MCE treatment showed the inverse of these response to return tomato plants to normal state and enhanced tolerance and resistance to heavy metal stress. In the present study, we emphasized that MCE can alleviate H.M stress, enhance tomato plant growth nutrients absorption and improve biochemical responses.

Keywords: microalgae crude extract, heavy metal stress, nutrient uptake, metabolomic analysis, solanum lycopersicum (Tomato), phytostabilisation

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2055 Laboratory Evaluation of the Airborne Sound Insulation of Plasterboard Sandwich Panels Filled with Recycled Textile Material

Authors: Svetlana Trifonova Djambova, Natalia Bobeva Ivanova, Roumiana Asenova Zaharieva

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Small size acoustic chamber test method has been applied to experimentally evaluate and compare the airborne sound insulation provided by plasterboard sandwich panels filled with mineral wool and with its alternative from recycled textile material (produced by two different technologies). A sound source room is used as an original small-size acoustic chamber, specially built in a real-size room, utilized as a sound receiving room. The experimental results of one of the recycled textile material specimens have demonstrated sound insulation properties similar to those of the mineral wool specimen and even superior in the 1600-3150 Hz frequency range. This study contributes to the improvement of recycled textile material production, as well as to the synergy of heat insulation and sound insulation performances of building materials.

Keywords: airborne sound insulation, heat insulation products, mineral wool, recycled textile material

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2054 Determination of Heavy Metal Levels in Carissa spinarum and Toddalia asiatica Used as Herbal Medicines in Kisii and Nyamira Counties Region, Kenya

Authors: Moses A. Guto Maobe, Leonard Gitu, Erastus Gatebe

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The plants Carissa spinarum and Toddalia asiatica have historically been used as herbal medicines in Kisii and Nyamira Counties region, Kenya. But, there is limited study about heavy metal contents in their different plant parts. Such information is necessary for proper use of the two plant species as herbal medicines. So, precise determination of heavy metal contents in different part of these herbs is required for quality, efficacy and safety use in the treatment of ailments. The main aim of this study was to standardize the two herbs of interest. The objective of this study was to evaluate the levels of heavy metal contents in the root of Carissa spinarum and Toddalia asiatica. A wet digestion method with concentrated nitric-hydrochloric acid was used for the dissolution of each herb part prior to elemental analysis. Standard solutions of various concentrations of each pure metal of analytical grade arsenic (As), cadmium (Cd) and mercury (Hg) were prepared and used. The analysis of As, Cd and Hg in each of two herbs was conducted by atomic absorption spectroscopy (AAS) Shimadzu model No. 6200. Data obtained from root of Carissa spinarum indicated concentration (mgkg⁻¹) of Arsenic (As), Cadmium (Cd) and Mercury (Hg) were 0.87 x 10⁻³, 7.02 x 10⁻⁶ and 0.66 x 10⁻³ respectively. Results obtained from root of Toddalia asiatica showed concentration (mgkg⁻¹) of Arsenic (As), Cadmium (Cd) and Mercury (Hg) were 1.33 x 10⁻³, 7.32 x 10⁻⁶ and 1.13 x 10⁻³, respectively. The permissible limits set by WHO for As, Cd and Hg in herbs are (mgkg⁻¹) < 1 - 5, < 0.3 – 1 and < 0.1- 0.5 respectively. The concentrations of As, Cd, and Hg determined were relatively higher in the root of Toddalia asiatica than the root of Carissa spinarum. It was concluded that levels of heavy metal contents of As, Cd, and Hg in the root of Carissa spinarum and Toddalia asiatica were within permissible limits set by WHO/FAO.

Keywords: heavy metals, Carissa spinarum, Toddalia asiatica, wet digestion, pollutants, AAS

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2053 Geostatistical Analysis of Contamination of Soils in an Urban Area in Ghana

Authors: S. K. Appiah, E. N. Aidoo, D. Asamoah Owusu, M. W. Nuonabuor

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Urbanization remains one of the unique predominant factors which is linked to the destruction of urban environment and its associated cases of soil contamination by heavy metals through the natural and anthropogenic activities. These activities are important sources of toxic heavy metals such as arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), and lead (Pb), nickel (Ni) and zinc (Zn). Often, these heavy metals lead to increased levels in some areas due to the impact of atmospheric deposition caused by their proximity to industrial plants or the indiscriminately burning of substances. Information gathered on potentially hazardous levels of these heavy metals in soils leads to establish serious health and urban agriculture implications. However, characterization of spatial variations of soil contamination by heavy metals in Ghana is limited. Kumasi is a Metropolitan city in Ghana, West Africa and is challenged with the recent spate of deteriorating soil quality due to rapid economic development and other human activities such as “Galamsey”, illegal mining operations within the metropolis. The paper seeks to use both univariate and multivariate geostatistical techniques to assess the spatial distribution of heavy metals in soils and the potential risk associated with ingestion of sources of soil contamination in the Metropolis. Geostatistical tools have the ability to detect changes in correlation structure and how a good knowledge of the study area can help to explain the different scales of variation detected. To achieve this task, point referenced data on heavy metals measured from topsoil samples in a previous study, were collected at various locations. Linear models of regionalisation and coregionalisation were fitted to all experimental semivariograms to describe the spatial dependence between the topsoil heavy metals at different spatial scales, which led to ordinary kriging and cokriging at unsampled locations and production of risk maps of soil contamination by these heavy metals. Results obtained from both the univariate and multivariate semivariogram models showed strong spatial dependence with range of autocorrelations ranging from 100 to 300 meters. The risk maps produced show strong spatial heterogeneity for almost all the soil heavy metals with extremely risk of contamination found close to areas with commercial and industrial activities. Hence, ongoing pollution interventions should be geared towards these highly risk areas for efficient management of soil contamination to avert further pollution in the metropolis.

Keywords: coregionalization, heavy metals, multivariate geostatistical analysis, soil contamination, spatial distribution

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2052 Physico-Chemical Characteristics and Possibilities of Utilization of Elbasan Thermal Waters

Authors: Elvin Çomo, Edlira Tako, Albana Hasimi, Rrapo Ormeni, Olger Gjuzi, Mirela Ndrita

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In Albania, only low enthalpy geothermal springs and wells are known, the temperatures of some of them are almost at the upper limits of low enthalpy, reaching over 60°C. These resources can be used to improve the country's energy balance, as well as for profitable economic purposes. The region of Elbasan has the greatest geothermal energy potential in Albania. This bass is one of the most popular and used in our country. This area is a surface with a number of sources, located in the form of a chain, in the sector between Llixha and Hidraj and constitutes a thermo-mineral basin with stable discharge and high temperature. The sources of Elbasan Springs, with the current average flow of thermo mineral water of 12-18 l/s and its temperature 55-65oC, have specific reserves of 39.6 GJ/m2 and potential power to install 2760 kW. For the assessment of physico-chemical parameters and heavy metals, water samples were taken at 5 monitoring stations throughout the year 2022. The levels of basic parameters were analyzed using ISO, EU and APHA 21-th edition standard methods. This study presents the current state of the physico-chemical parameters of this thermal basin, the evaluation of these parameters for curative activities and for industrial processes, as well as the integrated utilization of geothermal energy. Possibilities for using thermomineral waters for heating homes in the area around them or even further, depending on the flow from the source or geothermal well. Sensitization of Albanian investors, medical research and the community for the high economic and curative effectiveness, for the integral use of geothermal energy in this area and the development of the tourist sector. An analysis of the negative environmental impact from the use of thermal water is also provided.

Keywords: geothermal energy, Llixha, physic-chemical parameters, thermal water

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2051 Evaluation of Heavy Metal Contamination and Assessment of the Suitability of Water for Irrigation: A Case Study of the Sand River, Limpopo Province, South Africa

Authors: Ngonidzashe Moyo, Mmaditshaba Rapatsa

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The primary objective of this study was to determine heavy metal contamination in the water, sediment, grass and fish in Sand River, South Africa. This river passes through an urban area and sewage effluent is discharged into it. Water from the Sand river is subsequently used for irrigation downstream of the sewage treatment works. The suitability of this water and the surrounding boreholes for irrigation was determined. This study was undertaken between January, 2014 and January, 2015. Monthly samples were taken from four sites. Sites 1 was upstream of the Polokwane Wastewater Treatment Plant, sites 2, 3 and 4 were downstream. Ten boreholes in the vicinity of the Sand River were randomly selected and the water was tested for heavy metal contamination. The concentration of heavy metals in Sand River water followed the order Mn>Fe>Pb>Cu≥Zn≥Cd. Manganese concentration averaged 0.34 mg/L. Heavy metal concentration in the sediment, grass and fish followed the order Fe>Mn>Zn>Cu>Pb>Cd. The bioaccumulation factor from grass to fish was highest in manganese (19.25), followed by zinc (16.39) and iron (14.14). Soil permeability index (PI) and sodium adsorption ratio (SAR) were used to determine the suitability of Sand River and borehole water for irrigation. The PI index for Sand River water was 75.1% and this indicates that Sand River water is suitable for irrigation of crops. The PI index for the borehole water ranged from 65.8-72.8% and again this indicates suitability of borehole water for crop irrigation. The sodium adsorption ratio also indicated that both Sand River and borehole water were suitable for irrigation. A risk assessment study is recommended to determine the suitability of the fish for human consumption.

Keywords: bioaccumulation, bioavailability, heavy metals, sodium adsorption ratio

Procedia PDF Downloads 192
2050 Reduction of Plutonium Production in Heavy Water Research Reactor: A Feasibility Study through Neutronic Analysis Using MCNPX2.6 and CINDER90 Codes

Authors: H. Shamoradifar, B. Teimuri, P. Parvaresh, S. Mohammadi

Abstract:

One of the main characteristics of Heavy Water Moderated Reactors is their high production of plutonium. This article demonstrates the possibility of reduction of plutonium and other actinides in Heavy Water Research Reactor. Among the many ways for reducing plutonium production in a heavy water reactor, in this research, changing the fuel from natural Uranium fuel to Thorium-Uranium mixed fuel was focused. The main fissile nucleus in Thorium-Uranium fuels is U-233 which would be produced after neutron absorption by Th-232, so the Thorium-Uranium fuels have some known advantages compared to the Uranium fuels. Due to this fact, four Thorium-Uranium fuels with different compositions ratios were chosen in our simulations; a) 10% UO2-90% THO2 (enriched= 20%); b) 15% UO2-85% THO2 (enriched= 10%); c) 30% UO2-70% THO2 (enriched= 5%); d) 35% UO2-65% THO2 (enriched= 3.7%). The natural Uranium Oxide (UO2) is considered as the reference fuel, in other words all of the calculated data are compared with the related data from Uranium fuel. Neutronic parameters were calculated and used as the comparison parameters. All calculations were performed by Monte Carol (MCNPX2.6) steady state reaction rate calculation linked to a deterministic depletion calculation (CINDER90). The obtained computational data showed that Thorium-Uranium fuels with four different fissile compositions ratios can satisfy the safety and operating requirements for Heavy Water Research Reactor. Furthermore, Thorium-Uranium fuels have a very good proliferation resistance and consume less fissile material than uranium fuels at the same reactor operation time. Using mixed Thorium-Uranium fuels reduced the long-lived α emitter, high radiotoxic wastes and the radio toxicity level of spent fuel.

Keywords: Heavy Water Reactor, Burn up, Minor Actinides, Neutronic Calculation

Procedia PDF Downloads 228
2049 A Study of Anoxic - Oxic Microbiological Technology for Treatment of Heavy Oily Refinery Wastewater

Authors: Di Wang, Li Fang, Shengyu Fang, Jianhua Li, Honghong Dong, Zhongzhi Zhang

Abstract:

Heavy oily refinery wastewater with the characteristics of high concentration of toxic organic pollutant, poor biodegradability and complicated dissolved recalcitrant compounds is intractable to be degraded. In order to reduce the concentrations of COD and total nitrogen pollutants which are the major pollutants in heavy oily refinery wastewater, the Anoxic - Oxic microbiological technology relies mainly on anaerobic microbial reactor which works with methanogenic archaea mainly that can convert organic pollutants to methane gas, and supplemented by aerobic treatment. The results of continuous operation for 2 months with a hydraulic retention time (HRT) of 60h showed that, the COD concentration from influent water of anaerobic reactor and effluent water from aerobic reactor were 547.8mg/L and 93.85mg/L, respectively. The total removal rate of COD was up to 84.9%. Compared with the 46.71mg/L of total nitrogen pollutants in influent water of anaerobic reactor, the concentration of effluent water of aerobic reactor decreased to 14.11mg/L. In addition, the average removal rate of total nitrogen pollutants reached as high as 69.8%. Based on the data displayed, Anoxic - Oxic microbial technology shows a great potential to dispose heavy oil sewage in energy saving and high-efficiency of biodegradation.

Keywords: anoxic - oxic microbiological technology, COD, heavy oily refinery wastewater, total nitrogen pollutant

Procedia PDF Downloads 464
2048 Heavy Metal Contents in Vegetable Oils of Kazakhstan Origin and Life Risk Assessment

Authors: A. E. Mukhametov, M. T. Yerbulekova, D. R. Dautkanova, G. A. Tuyakova, G. Aitkhozhayeva

Abstract:

The accumulation of heavy metals in food is a constant problem in many parts of the world. Vegetable oils are widely used, both for cooking and for processing in the food industry, meeting the main dietary requirements. One of the main chemical pollutants, heavy metals, is usually found in vegetable oils. These chemical pollutants are carcinogenic, teratogenic and immunotoxic, harmful to consumption and have a negative effect on human health even in trace amounts. Residues of these substances can easily accumulate in vegetable oil during cultivation, processing and storage. In this article, the content of the concentration of heavy metal ions in vegetable oils of Kazakhstan production is studied: sunflower, rapeseed, safflower and linseed oil. Heavy metals: arsenic, cadmium, lead and nickel, were determined in three repetitions by the method of flame atomic absorption. Analysis of vegetable oil samples revealed that the largest lead contamination (Pb) was determined to be 0.065 mg/kg in linseed oil. The content of cadmium (Cd) in the largest amount of 0.009 mg/kg was found in safflower oil. Arsenic (As) content was determined in rapeseed and safflower oils at 0.003 mg/kg, and arsenic (As) was not detected in linseed and sunflower oil. The nickel (Ni) content in the largest amount of 0.433 mg/kg was in linseed oil. The heavy metal contents in the test samples complied with the requirements of regulatory documents for vegetable oils. An assessment of the health risk of vegetable oils with a daily consumption of 36 g per day shows that all samples of vegetable oils produced in Kazakhstan are safe for consumption. But further monitoring is needed, since all these metals are toxic and their harmful effects become apparent only after several years of exposure.

Keywords: vegetable oil, sunflower oil, linseed oil, safflower oil, toxic metals, food safety, rape oil

Procedia PDF Downloads 112
2047 The Batch Method Approach for Adsorption Mechanism Processes of Some Selected Heavy Metal Ions and Methylene Blue by Using Chemically Modified Luffa Cylindrica

Authors: Akanimo Emene, Mark D. Ogden, Robert Edyvean

Abstract:

Adsorption is a low cost, efficient and economically viable wastewater treatment process. Utilization of this treatment process has not been fully applied due to the complex and not fully understood nature of the adsorption system. To optimize its process is to choose a sufficient adsorbent and to study further the experimental parameters that influence the adsorption design system. Chemically modified adsorbent, Luffa cylindrica, was used to adsorb heavy metal ions and an organic pollutant, methylene blue, from aqueous environmental solution at varying experimental conditions. Experimental factors, adsorption time, initial metal ion or organic pollutant concentration, ionic strength, and pH of solution were studied. The experimental data were analyzed with kinetic and isotherm models. The antagonistic effect of the methylene and some heavy metal ions were recorded. An understanding of the use of this treated Luffa cylindrica for the removal of these toxic substances will establish and improve the commercial application of the adsorption process in treatment of contaminated waters.

Keywords: adsorption, heavy metal ions, Luffa cylindrica, wastewater treatment

Procedia PDF Downloads 170
2046 Adsorption and Transformation of Lead in Coimbatore Urban Soils

Authors: K. Sivasubramanin, S. Mahimairaja, S. Pavithrapriya

Abstract:

Heavy metal pollution originating from industrial wastes is becoming a serious problem in many urban environments. These heavy metals, if not properly managed, could enter into the food chain and cause a serious health hazards in animals and humans. Industrial wastes, sewage sludge, and automobile emissions also contribute to heavy metal like Pb pollution in the urban environment. However, information is scarce on the heavy metal pollution in Coimbatore urban environment. Therefore, the current study was carried out to examine the extent of lead pollution in Coimbatore urban environment the maximum Pb concentration in Coimbatore urban environment was found in ukkadam, whose concentration in soils 352 mg kg-1. In many places, the Pb concentration was found exceeded the permissible limit of 100 mg kg-1. In laboratory, closed incubation experiment showed that the concentration of different species of Pb viz., water soluble Pb(H2O-Pb), exchangeable Pb(KNO3-Pb), organic-Pb(NaOH-Pb), and organic plus metal (Fe & Al) oxides bound-Pb(Na2 EDTA-Pb) was found significantly increased during the 15 days incubation, mainly due to biotransformation processes. Both the moisture content of soil and ambient temperature exerted a profound influence on the transformation of Pb. The results of a batch experiment has shown that the sorption data was adequately described by the Freundlich equation as indicated by the high correlation coefficients (R2= 0.64) than the Langmuir equation (R2 = 0.33). A maximum of 86 mg of Pb was found adsorbed per kilogram of soil. Consistently, a soil column experiment result had shown that only a small amount of Pb( < 1.0 µg g-1 soil) alone was found leached from the soil. This might be due to greater potential of the soil towards Pb adsorption.

Keywords: lead pollution, adsorption, transformation, heavy metal pollution

Procedia PDF Downloads 305
2045 Free Vibration Analysis of Composite Beam with Non-Uniform Section Using Analytical, Numerical and Experimental Method

Authors: Kadda Boumediene, Mohamed Ziani

Abstract:

Mainly because of their good ratio stiffness/mass, and in addition to adjustable mechanical properties, composite materials are more and more often used as an alternative to traditional materials in several domains. Before using these materials in practical application, a detailed and precise characterization of their mechanical properties is necessary. In the present work, we will find a dynamic analyze of composite beam (natural frequencies and mode shape), an experimental vibration technique, which presents a powerful tool for the estimation of mechanical characteristics, is used to characterize a dissimilar beam of a Mortar/ natural mineral fiber. The study is completed by an analytic (Rayleigh & Rayleigh-Ritz), experimental and numerical application for non-uniform composite beam of a Mortar/ natural mineral fiber. The study is supported by a comparison between numerical and analytic results as well as a comparison between experimental and numerical results.

Keywords: composite beam, mortar/ natural mineral fiber, mechanical characteristics, natural frequencies, mode shape

Procedia PDF Downloads 328
2044 Vermicomposting Amended With Microorganisms and Biochar: Phytopathogen Resistant Seedbeds for Vegetables and Heavy Metal Polluted Waste Treatment

Authors: Fuad Ameen, Ali A. Al-Homaidan

Abstract:

Biochar can be used in numerous biotechnological applications due to its properties to adsorb beneficial nutrients and harmful pollutants. Objectives: We aimed to treat heavy metal polluted organic wastes using vermicomposting process and produce a fertilizer that can be used in agriculture. We improved the process by adding biochar as well as microbial inoculum and biomass into household waste or sewage sludge before vermicomposting. The earthworm Eisenia fetida used in vermicomposting was included to accumulate heavy metals, biochar to adsorb heavy metals, and the microalga Navicula sp. or the mangrove fungus Acrophialophora sp. to promote plant growth in the final product used as a seedbed for Solanaceae vegetables. We carried out vermicomposting treatments to see the effect of different amendments. Final compost quality was analyzed for maturity. The earthworms were studied for their vitality, heavy metal accumulation, and metallothionein protein content to verify their role in the process. The compost was used as a seedbed for vegetables that were inoculated with a phytopathogen Pythium sp. known to cause root rot and destroy seeds. Compost as seedbed promoted plant growth and reduced disease symptoms in leaves. In the treatment where E. fetida, 6% biochar, and Navicula sp. had been added, 90% of the seeds germinated, while less than 20% germinated in the control treatment. The experimental plants had acquired resistance against Pythium sp. The metagenomic profile of microbial communities will be reported.

Keywords: organic wastes, vermicomposting process, biochar, mangrove fungus

Procedia PDF Downloads 61
2043 Mineral Status of Feeds and Fodder and Its Subsequent Effect on Plasma of Livestock and Its Products in Red Lateritic Zone of West Bengal, India

Authors: S. K. Pyne, M. Mondal, G. Samanta

Abstract:

A survey was carried out in red lateritic zone of West Bengal to compare the mineral status in plasma of livestock grazing over red lateritic region. Sufficient number of samples of soil, feeds, fodder and blood were collected from four districts of red lateritic zone namely, West Midnapore, Birbhum, Bankura and Purulia respectively. The samples were analysed for Calcium (Ca), Phosphorus (P), Copper (Cu), Zinc (Zn), Manganese (Mn) and Iron (Fe). Concentration of Cu, Mn and Fe in soil were above the minimum critical level, whereas, Zn deficiency is wide spread in red lateritic soil. Paddy straw is deficient in Ca, P, Zn and Mn in the region. Green fodders are also deficient in P, Cu, Zn. The richness of iron (Fe) in soil, feeds, fodder and tree leaves is the characteristics of this region. Phosphorus is deficient in plasma of all categories of livestock with the exception of bullock. Cu is deficient in plasma of calf. Plasma Mn and Fe were higher (p<0.01) in the animals of red lateritic zone. The study reveals that the overall deficiency of phosphorus in different categories of livestock and there is need of dietary supplementation.

Keywords: mineral, red lateritic zone, grazing livestock, plasma

Procedia PDF Downloads 302
2042 Long-Term Tillage, Lime Matter and Cover Crop Effects under Heavy Soil Conditions in Northern Lithuania

Authors: Aleksandras Velykis, Antanas Satkus

Abstract:

Clay loam and clay soils are typical for northern Lithuania. These soils are susceptible to physical degradation in the case of intensive use of heavy machinery for field operations. However, clayey soils having poor physical properties by origin require more intensive tillage to maintain proper physical condition for grown crops. Therefore not only choice of suitable tillage system is very important for these soils in the region, but also additional search of other measures is essential for good soil physical state maintenance. Research objective: To evaluate the long-term effects of different intensity tillage as well as its combinations with supplementary agronomic practices on improvement of soil physical conditions and environmental sustainability. The experiment examined the influence of deep and shallow ploughing, ploughless tillage, combinations of ploughless tillage with incorporation of lime sludge and cover crop for green manure and application of the same cover crop for mulch without autumn tillage under spring and winter crop growing conditions on clay loam (27% clay, 50% silt, 23% sand) Endocalcaric Endogleyic Cambisol. Methods: The indicators characterizing the impact of investigated measures were determined using the following methods and devices: Soil dry bulk density – by Eijkelkamp cylinder (100 cm3), soil water content – by weighing, soil structure – by Retsch sieve shaker, aggregate stability – by Eijkelkamp wet sieving apparatus, soil mineral nitrogen – in 1 N KCL extract using colorimetric method. Results: Clay loam soil physical state (dry bulk density, structure, aggregate stability, water content) depends on tillage system and its combination with additional practices used. Application of cover crop winter mulch without tillage in autumn, ploughless tillage and shallow ploughing causes the compaction of bottom (15-25 cm) topsoil layer. However, due to ploughless tillage the soil dry bulk density in subsoil (25-35 cm) layer is less compared to deep ploughing. Soil structure in the upper (0-15 cm) topsoil layer and in the seedbed (0-5 cm), prepared for spring crops is usually worse when applying the ploughless tillage or cover crop mulch without autumn tillage. Application of lime sludge under ploughless tillage conditions helped to avoid the compaction and structure worsening in upper topsoil layer, as well as increase aggregate stability. Application of reduced tillage increased soil water content at upper topsoil layer directly after spring crop sowing. However, due to reduced tillage the water content in all topsoil markedly decreased when droughty periods lasted for a long time. Combination of reduced tillage with cover crop for green manure and winter mulch is significant for preserving the environment. Such application of cover crops reduces the leaching of mineral nitrogen into the deeper soil layers and environmental pollution. This work was supported by the National Science Program ‘The effect of long-term, different-intensity management of resources on the soils of different genesis and on other components of the agro-ecosystems’ [grant number SIT-9/2015] funded by the Research Council of Lithuania.

Keywords: clay loam, endocalcaric endogleyic cambisol, mineral nitrogen, physical state

Procedia PDF Downloads 202
2041 Thermochemical Modelling for Extraction of Lithium from Spodumene and Prediction of Promising Reagents for the Roasting Process

Authors: Allen Yushark Fosu, Ndue Kanari, James Vaughan, Alexandre Changes

Abstract:

Spodumene is a lithium-bearing mineral of great interest due to increasing demand of lithium in emerging electric and hybrid vehicles. The conventional method of processing the mineral for the metal requires inevitable thermal transformation of α-phase to the β-phase followed by roasting with suitable reagents to produce lithium salts for downstream processes. The selection of appropriate reagent for roasting is key for the success of the process and overall lithium recovery. Several researches have been conducted to identify good reagents for the process efficiency, leading to sulfation, alkaline, chlorination, fluorination, and carbonizing as the methods of lithium recovery from the mineral.HSC Chemistry is a thermochemical software that can be used to model metallurgical process feasibility and predict possible reaction products prior to experimental investigation. The software was employed to investigate and explain the various reagent characteristics as employed in literature during spodumene roasting up to 1200°C. The simulation indicated that all used reagents for sulfation and alkaline were feasible in the direction of lithium salt production. Chlorination was only feasible when Cl2 and CaCl2 were used as chlorination agents but not NaCl nor KCl. Depending on the kind of lithium salt formed during carbonizing and fluorination, the process was either spontaneous or nonspontaneous throughout the temperature range investigated. The HSC software was further used to simulate and predict some promising reagents which may be equally good for roasting the mineral for efficient lithium extraction but have not yet been considered by researchers.

Keywords: thermochemical modelling, HSC chemistry software, lithium, spodumene, roasting

Procedia PDF Downloads 132
2040 Effect of Heat Treatment on the Hardness and Abrasiveness of Almandine and Pyrope Garnet for Water-Cutting of Marble

Authors: Mahmoud Rabh

Abstract:

Garnet has been used for decades as an abrasive in water jet cutting and sand blasting because of its superior physical properties. When added to use in water-cutting process of marble. A standard commercial sample of the mineral was tested in terms of the hardness and abrasiveness properties. The sample was sized to 4 fractions having the size of < 60 um, > 60 < 100 um, > 100 < 180 um > 1280 < 250 and 250 um designated the symbols, FF, MF, MC and C respectively. Each sample was separately heated in controlled conditions at temperatures up to 1000 °C at a heating rate of 10°C/min in an electrically heated chamber furnace. Soaking time at the maximum temperature was up to 6 h. Hardness and abrasiveness properties of the heat treated samples were tested to cut marble having a thickness of 25 mm. Results revealed that H/A of the natural garnet mineral increased by heating at temperatures up to 600°C and exhibited pronounced decrease with higher temperatures up to 1000 °C. Results were explained in the light of a structural irreversible dislocation (SD) of the crystals of garnet almandine Fe2+3Al2Si3O12 and pyrope Mg3Al2Si3O12. Characterization of the mineral was carried out with the help of XRD, SEM and FT-IR measurements.

Keywords: garnet abrasive, heat treatment, water jet cutting, hardness abrasiveness

Procedia PDF Downloads 308
2039 The Influence of Sulfate and Magnesium Ions on the Growth Kinetics of CaCO3

Authors: Kotbia Labiod, Mohamed Mouldi Tlili

Abstract:

The presence of different mineral salts in natural waters may precipitate and form hard deposits in water distribution systems. In this respect, we have developed numerous works on scaling by Algerian water with a very high hardness of 102 °F. The aim of our work is to study the influence of water dynamics and its composition on mineral salts on the precipitation of calcium carbonate (CaCO3). To achieve this objective, we have adopted two precipitation techniques based on controlled degassing of dissolved CO2. This study will identify the causes and provide answers to this complex phenomenon.

Keywords: calcium carbonate, controlled degassing, precipitation, scaling

Procedia PDF Downloads 200