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Number of results: 33
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Keywords fly ash REE leaching
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Abstract

The aim of the work was to draw attention to the usefulness of the alkaline thermal activation process with sodium hydroxide in the process of rare earth metal leaching (REE), from fly ash with hydrochloric acid and nitric acid(V). The work is a part of the authors’ own research aimed at optimizing the REE recovery process coming from fly ash from hard coal combustion.

The article contains an assessment of the possibility of leaching rare earth metals (REE) from fly ash originating from the combustion of hard coal in one of the Polish power plants. The process was carried out for various samples consisting of fly ash and sodium hydroxide and for different temperatures and reaction times. The process was carried out for samples consisting of fly ash and sodium hydroxide containing respectively 10, 20 and 30% on NaOH by weight in relation to the weight of fly ash. Homogenization of these mixtures was carried out wet, and then they were baked at 408K, 433K and 473K, for a period of three hours. The mixture thus obtained was ground to a particle size of less than 0.1 mm and washed with hot water to remove excessive NaOH. The solid post-reaction residue was digested in concentrated HCl at 373K for 1 hour at a weight ratio fs/fc of 1:10. The results of chemical analysis and scanning microscopic analysis along with EDS analysis and X-ray analysis were used to characterize the physicochemical properties of the tested material.

The results indicated that REE recovery from fly ash strictly depends on heat treatment temperature with NaOH, and an increase in REE recovery from alkaline-activated fly ash along with increasing the amount of NaOH in relation to fly ash mass.

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Authors and Affiliations

Sylwester Żelazny
Henryk Świnder
ORCID: ORCID
Andrzej Jarosiński
Barbara Białecka
ORCID: ORCID
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Abstract

Oxide fraction of industrial zinc ash from hot dip galvanizing was characterized in terms of composition and leaching behaviour in 10% sulfuric acid solution. Waste product contained about 68% Zn, 6% Cl, 3% Al, 1% Fe, 0.7% Si, 0.5% Pb and minor percentages of other metals (Mn, Cu, Ti etc.). It consisted mainly of zinc oxide contaminated with metallic zinc, zinc hydroxide chloride and silica. Dissolution of the metals from the material was determined as a function of solid to liquid ratio (50-150 kg/m3), temperature (20°C and 35°C) and agitation rate (300 and 900 rpm). The best results (50 g/dm3 Zn(II) at 78% zinc recovery) were obtained for 100 kg/m3 and the temperature of 20°C. Increase in the agitation rate had weak effect on the zinc yield. The final solutions were contaminated mainly by Fe(II, III) ions. Leaching of the material was an exothermic process with the reaction heat of about 800 kJ/kg.
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Authors and Affiliations

G. Włoch
E. Rudnik
L. Szatan
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Abstract

This work presents results of the release of polycyclic aromatic hydrocarbons (PAH) from granules composed of fly ashes, which are the product of hard and coal combustion and sewage sludge. 3 types of granulates by a weight ratio of ash to sludge 3:7 and 1: 1 were used. The research of PAH leaching was conducted within a simulated period of 24 months, with the examination of PAH washing out every three months. The highest amounts of PAH (297 - 330 μg/kg dw.) were obtained_from granulates containing 7 parts by weights of sewage sludge (3 times higher in comparison with the granulate containing ash and sludge in ratio of I: 1 ). The maximum PAH release from all the examined granulates took place in the 9th month of the research. Benzo(k)fluoranthene revealed the highest fraction (67.4-76.0%) of all examined compounds.
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Authors and Affiliations

Czesława Rosik-Dulewska
ORCID: ORCID
Urszula Karwaczyńska
Tomasz Ciesielczuk
ORCID: ORCID
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Abstract

Industrial steelmaking (EAF) flue dust was characterized in terms of chemical and phase compositions, leaching behaviour in 20% sulphuric acid solution as well as leaching thermal effect. Waste product contained about 43% Zn, 27% Fe, 19% O, about 3% Pb and Mn and lesser amounts of other elements (Ca, Si, Mo, etc.). It consisted mainly of oxide-type compounds of iron and zinc. Dissolution of metals (Zn, Fe, Mn) from the dust was determined in a dependence of solid to liquid ratio (50-200 g/L), temperature (20-80oC) and leaching time (up to 120 min). The best result of 60% zinc recovery was obtained for 50 g dust/L and a temperature of 80oC. Leaching of the material was an exothermic process with a reaction heat of about –318 kJ/kg. Precipitation purification of the solution was realized using various ratios of H2O2 to NH3aq. A product of this stage was hydrated iron(III) oxide. Final solution was used for zinc electrowinning. Despite that pure zinc was obtained the highest cathodic current efficiency was only 40%.

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Authors and Affiliations

E. Rudnik
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Abstract

New technologies and the globalization of the electrical and electronic equipment market cause a continuous increase in the amount of electrical and electronic waste. They constitute one of the waste groups that grows the fastest in quantity. The development of the new generation of electrical and electronic devices is much faster than before. Recently attention has been concentrated on hydrometallurgical methods for the recovery of metals from electronic waste. In this article the role of an oxidizing agent, mainly ozone and hydrogen peroxide was presented in hydrometallurgical processes. Leaching process of printed circuits boards (PCBs) from used cell phones was conducted. The experiments were carried out in the presence of sulfuric acid and ozone as an oxidizing agent for various temperatures, acid concentration, ozone concentration. As a result, the concentrations of copper, zinc, iron and aluminum in the obtained solution were measured. The obtained results were compared to results obtained earlier in the presence of hydrogen peroxide as an oxidizing agent and discussed.
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Authors and Affiliations

M. Saternus
A. Fornalczyk
M. Lisińska
J. Willner
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Abstract

There are two methods to produce primary copper: hydrometallurgical and pyrometallurgical. Copper concentrates, from which copper

matte is melted, constitute the charge at melting primary copper in the pyrometallurgical process. This process consists of a few stages, of

which the basic ones are roasting and smelting. Smelting process may be bath and flash. Slag from copper production, on the end of

process contain less 0,8%. It is treat as a waste or used other field, but only in a few friction. The slag amount for waste management or

storage equaled 11 741 – 16 011 million tons in 2011. This is a serious ecological problem. The following slags were investigated: slag

originated from the primary copper production process in the flash furnace of the Outtokumpuja Company in HM Głogów 2 (Sample S2):

the same slag after the copper removal performed according the up to now technology (Sample S1): slag originated from the primary

copper production process in the flash furnace of the Outtokumpuja Company in HM Głogów 2, after the copper removal performed

according the new technology (Sample S3). In practice, all tested slags satisfy the allowance criteria of storing on the dumping grounds of

wastes other than hazardous and neutral.

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Authors and Affiliations

W. Wołczyński
M. Holtzer
A. Bydałek
A. Kmita
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Abstract

Sludge from cardboard mill is most commonly landfilled, but it could also be recycled on-site into production or reused in some other way. In this study the use of sludge from cardboard mill as stabilizing agent in the stabilization treatment of cadmium polluted sediment was examined. The effectiveness of treatment and long-term leaching behavior of cadmium was evaluated by determining the cumulative percentage of cadmium leached, diffusion coefficients (De) and by applying different leaching tests (semi-dynamic test, toxicity characteristic leaching procedure, waste extraction test). In order to simulate the “worst case” leaching conditions, the semi-dynamic leaching test was modified using 0.014 M acetic acid (pH = 3.25) and humic acids solution (20 mg l-1 TOC) as leachants instead of deionized water. A diffusion-based model was used to elucidate the controlling leaching mechanisms. Applied treatment was effective in immobilizing cadmium irrespective of high availability in the untreated sample. The controlling leaching mechanism appeared to be diffusion, which indicates that a slow leaching of cadmium could be expected when the cardboard mill sludge as stabilization agent is applied.

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Authors and Affiliations

Milena Becelic
Miljana Prica
Milena Dalmacija
Bozo Dalmacija
Vesna Pesic
Dejan Krcmar
Rastko Milosevic
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Abstract

In this research, the high arsenic content dust of copper smelting, as a raw material, the extraction of copper and arsenic from the high arsenic content dust in the leaching system containing acidic and alkaline compounds was investigated. Meanwhile, the effects of acid/alkaline initial concentration, liquid to solid ratio, leaching temperature, leaching time on the leaching rate of copper and arsenic were studied. The optimum conditions for the leaching of high arsenic content dust and preparation of copper arsenate were determined. The results showed that acidic/alkaline leaching of high arsenic content dust was particularly effective. 93.2% of the copper, and 91.6% of the arsenic were leached in an acidic leaching process and 95% of the arsenic, while less than 3% of the copper, less than 5% of the antimony, less than 2% of the bismuth was also leached in an alkaline leaching process. A new method (the parallel flow drop precipitate method) was developed in the synthesis of copper arsenate process. The parallel flow drop method was employed to adjust the molar ratio (copper to arsenic) of the mixed solution of the acid-leaching solution and the alkali-leaching solution by taking the drop acceleration of an acidic leaching solution and an alkaline leaching solution at 10 mL/min and 12 mL/min, at a temperature of 60°C and a reaction time of 1 h. Copper arsenate was prepared by mixing an acidic leaching solution and an alkaline leaching solution. The main phases of copper arsenate were CuHAsO4·1.5H2O and Cu5As4O15·9H2O. Copper arsenate contained 30.13% copper and 31.10% arsenic.

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Authors and Affiliations

W. Sheng
Y.-Y. Shen
Z. Sheng-Quan
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Abstract

The goal of the study was to determine the risk posed to soil, groundwater and plants by the application of sewage sludge from a mechanical-biological wastewater treatment plant of nominal capacity of 46 000 m3/d. as fertilizer. Soil samples were collected from an agricultural and vegetable production farm. The leaching experiment was carried out in PCV lizymeters (with percolation water outlet). With respect to the chemistry and biology, the analyzed sludge meets the standards set up for sludge used for agricultural purposes. After 8, 16 and 24 weeks of simulated leaching with atmospheric precipitation, the lecheate from lizymeters showed changes in pH (increasing tendency), electrolytic conductivity (decreasing tendency) as well as slightly lowering content of heavy metals. Heavy metal speciation in sewage sludge showed that they occur in forms of compounds sparingly releasable to the soil solution (fractions III, IV, V). The analysis of sequential chemical extraction carried out in soil with applied sewage sludge, after 24 weeks treatment with simulated atmospheric precipitation doses showed similar heavy metal occurrence tendency as in the case of pure sludge. The total heavy metal content in fractions I-III amounted from 18,6% for Cr to 44,8% for Zn. The remaining content of heavy metals was basically bound with fraction V, which is completely unavailable for plants.
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Authors and Affiliations

Czesława Rosik-Dulewska
ORCID: ORCID
Mirosław Mikszta
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Abstract

In this study, laboratory-scale experiments were carried out to investigate the effects of microwave-assisted alkaline leaching on the treatment of electric arc furnace dusts to recover zinc and lead. Microwave treatment is a new innovative technology in waste treatment and now is an attractive advanced inter-disciplinary field and also environmental friendly. The highest zinc extraction, 50.3% in 60 minutes using 5 M NaOH at 750 W and L:S ratio 20, and lead extraction up to 92.84% was achieved in these same conditions but in 30 minutes. Compared with conventional leaching, the top extraction rate using MW-assisted leaching was higher by 16% (Zn) and 26% (Pb). Zinc presents in the flue dust in the form of franklinite (ZnFe2O4), its leaching in sodium hydroxide does not occur under the examined conditions, because it is enclosed in a matrix of iron.

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Authors and Affiliations

M. Laubertova
T. Havlik
L. Parilak
B. Derin
J. Trpcevska
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Abstract

The presence of inorganic elements in solid fuels is not only considered a direct source of problems in the furnace but is also connected with the release of pollutants into air during combustion. This article focuses on the sintering characteristics of biomass and coal ashes, in particular on the leaching processes, and their impact on the tendency to sinter ash. Biomass and coal ash with high alkali metal concentration can deposit in boiler sections and cause severe operating problems such as slagging, fouling and corrosion of boiler and heat exchanger surface, limiting heat transfer. Two biomass types and one coal ash with different origin and different chemical compositions were investigated. A sequential leaching analysis was employed in this study to elucidate the modes of occurrence of metals that can transform into fuel extract. Sequential leaching analysis was conducted as a two-step process: using distilled water in the first step and acetic acid in the second step. The chemical composition of ashes, before and after each step of the leaching processwas studied using ICP-OES method. The standard Ash Fusion Temperature (AFTs) technique was also employed to assess the sintering tendency of the tested samples. It was observed that the presence of key elements such as sodium, potassium, magnesium and sulphur (elucidated in the leaching process) plays a significant role in sintering process. The sintering tendency enhances when the concentration of these elements increases.

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Authors and Affiliations

Arkadiusz Szydełko
Dorota Nowak-Woźny
Bartosz Urbanek
Laura González Valdés
Wiesław Rybak
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Abstract

This paper introduces a novel approach to building network cluster structures, based on the modified LEACH algorithm. The proposed solution takes into account the multitasking of the network infrastructure, resulting from various functions performed by individual nodes. Therefore, instead of a single head, dedicated to a given cluster, a set of heads is selected, the number of which corresponds to the number of performed functions. Outcomes of simulations, comparing the classical and the multifunctional approach, are presented. The obtained results confirm that both algorithms deliver similar levels of energy consumption, as well as efficiency in terms of the number of individual nodes discharged.
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Authors and Affiliations

A. Paszkiewicz
1
ORCID: ORCID
C. Ćwikła
2
M. Bolanowski
1
ORCID: ORCID
M. Ganzha
3
ORCID: ORCID
M. Paprzycki
3
ORCID: ORCID
M. Hodoň
4
ORCID: ORCID

  1. Department of Complex Systems, Rzeszow University of Technology, Al. Powstańców Warszawy 12, Rzeszów 35-959, Poland
  2. Rzeszow University of Technology, Al. Powstańców Warszawy 12, Rzeszów 35-959, Poland
  3. Systems Research Institute Polish Academy of Sciences, Newelska 6, Warszawa 01-447, Poland
  4. Department of Technical Cybernetics, University of Žilina, Univerzitná 8215/1, 010 26 Žilina, Slovakia
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Abstract

Contamination of soil with heavy metals has become a worldwide environmental problem, and receives great attention. In this study, we aim to investigate soil pollution level affected by an industrial district nearby. The total amount of typical heavy metals in the soils (Hengyang Songmu Industrial Park, Hunan Province, China) was analyzed. In addition, the fraction analysis and laboratory simulation leaching via different pH rainwater was carried out to study the migration and transformation of heavy metals. The main results show that the contents of Cu, Zn, Pb, Cr and Cd in the samples were higher than the soil background values in Hunan Province. The heavy metals forms, analyzed by sequential extraction method, show that the proportion of the unstable form of Cd, Zn and Pb was more than 50%. Igeo values indicate that the heavy metal pollution degree of soil sample #5 at the investigated area is recorded in the order of Cd(6.42), Zn(2.28), Cu(1.82), Pb(1.63), and Cr(0.37). Cu, Zn, Pb, Cr and Cd in this area could pose a potential leaching risk to the environment which may affect the food chain and constitute a threat to human health. It would be necessary to take steps to stabilize and monitor the heavy metals in soil.

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Authors and Affiliations

Wenfa Tan
Yuan Li
Lei Ding
Yachao Wang
Jiangxiang Li
Qinwen Deng
Feng Guo
Xue Xiao
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Abstract

The analysis of leaching behavior of harmful substances, such as arsenic, is one of the parameters of risk assessment resulting from the storage or economic use of coal waste. The leachability depends both on the environmental conditions of the storage area as well as on the properties of the waste material itself. There are a number of leaching tests that allow to model specific conditions or measure the specific properties of the leaching process. The conducted research aimed at comparing two methods with different application assumptions. The study of arsenic leaching from waste from the hard coal enrichment process was carried out in accordance with the Polish PN-EN 12457 standard and the US TCLP procedure. The leaching results obtained with both methods did not exceed the limit values of this parameter, defined in the Polish law. Both methods were also characterized by the good repeatability of the results. The use of an acetic acid solution (TCLP method) resulted in three times higher arsenic leaching from the examined waste compared to the use of deionized water as a leaching fluid (method PN-EN 12457). Therefore, the use of organic acid tests for mining waste intended for storage with municipal waste should be considered, as the results of the basic test based on clean water leaching may be inadequate to the actual leaching of arsenic under such environmental conditions.

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Authors and Affiliations

Dorota Makowska
Katarzyna Świątek
Faustyna Wierońska
Andrzej Strugała
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Abstract

Sixteen samples were designed for analysis (hard coal, aggregate – barren rock, hard coal sludge). The total mercury content and the amount of mercury leaching were determined. The percentage of leachable form in the total content was calculated. The studies were carried out under various pH medium. The leachability under conditions close to neutral was determined in accordance with the PN EN 12457/1-4 standard. The leachability under acidic medium (pH of the solution – approx. 3) was determined in accordance with principles of the TCLP method. The mercury content was determined by means of the AAS method. For hard coal the total mercury content was 0.0384–0.1049 mg/kg. The level of leaching on mean was 2.6%. At the acidic medium the amount of leaching increases to an mean 4.1%. The extractive waste of aggregate type features a higher total mercury content in the finest fraction < 6 mm (up to 0.4564 mg/kg) and a lower content in the fraction 80–120 mm (up to 0.1006 mg/kg). The aggregate shows the percentage of the leachable form on mean from 1.4 to 2.2%. With pH decreasing to approx. 3, the amount of leaching grows up to mean values of 1.7–3.2%. Coal sludge features the total mercury content of 0.1368–0.2178 mg/kg. The percentage of mercury leachable form is approx. 1.8%. With pH decreasing the value increases to mean value of 3.0%. In general, the leachability of mercury from hard coals and extractive waste is low, and the leachability in an acidic medium grows approx. twice. Such factors as the type and origin of samples, their grain composition, and the pH conditions, have basic importance for the process. The time of waste seasoning and its weathering processes have the greatest impact on increasing the leaching of mercury from the extractive waste.
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Authors and Affiliations

Beata Klojzy-Karczmarczyk
1
ORCID: ORCID
Janusz Mazurek
1
ORCID: ORCID

  1. Mineral and Energy Economy Research Institute of the Polish Academy of Sciences, Kraków, Poland
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Abstract

The problem of the migration of metal ions in the environment remains a current problem in light of the quality of obtained crops. The necessity of more and more frequent use of alternative sources of biogens in the form of waste substances, poses a threat of loading significant amounts of metals into the soil – including heavy metals harmful to human health and life. The article discusses a significant problem, namely the comparison of the results of the environmental impact of waste, obtained on the basis of legally authorized leaching tests (three-stage leaching test according to PN-EN 12457:2006), with results obtained from sequential chemical extraction (performed in 4-step chemical extraction developed and recommended in European Union countries by Communities Bureau of References – BCR). The study covered an investigation of industry fly ash from the combustion of lignite, in which Cu, Zn, Cd, Ni, Pb, Cr, Na, K, Li concentrations and loads were calculated. A mobility of analyzed elements was established on this basis. From heavy metals, the highest values in fraction I were noted for nickel and copper and zinc as well as nickel were noted for fraction IV . Peaking values of electrolytic conductivity in eluates was created by high concentrations of macroelements (Na and K). These tests confirm that the leaching tests used for their application in the natural environment indicate such concentrations at the highest levels that can be obtained at the first or second stage of sequential chemical extraction, and thus their proper full environmental impact is not known.

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Authors and Affiliations

Czesława Rosik-Dulewska
ORCID: ORCID
Urszula Karwaczyńska
Tomasz Ciesielczuk
ORCID: ORCID
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Abstract

The purpose of the present study was to extract high added value titanium from Ti-doped Seaside Magnetite Concentrated (Ti-SMC), which has a high potential reserve for Ti-Fe with 4–6% Ti, 50–52% F e, 1–2% A l, and 1–2% Mg content by applying innovative, economical, environmentally friendly methods. A gitaion HCl leaching was applied to the Ti-SMC sample at different leaching temperatures (25–50–75–90°C), at acid concentrations (8–10–12 N ), and leaching times (30–60– –120–240 min) in atmospheric conditions. A fter the leaching experiments under the indicated conditions, the optimization of the leaching experiments was determined with Ti% recovery that dissoluted by elemental analysis, and the titanium recovery values reached the maximum value with increased leaching time at 50°C and 10 N HCl acid concentration; and 65% Ti was recovered in 30 minutes, 67% in 60 minutes, 74% in 120 minutes, and 82% Ti in 240 minutes. F or Ti-SMC, leaching was carried out at 50°C leaching temperature and at 10 N acid concentration for 480 minutes, and a 92% Ti extraction value was achieved. A ccording to the extraction results of all leaching experiments, the leaching temperature of 50°C, the acid concentration of 10 N , and the leaching time of 480 minutes were determined as the optimum conditions. In this study, it was emphasized that this resource is a potential reserve, which has not been used as a source before, with 92% Ti extraction with atmospheric acid leaching, which is an environmentally friendly method, consuming less energy than Ti-SMC, which is difficult and expensive to extract with traditional methods.
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Authors and Affiliations

Elif Uzun Kart
1
ORCID: ORCID
Mümin Kırman
1
ORCID: ORCID

  1. Marmara University, İstanbul, Turkey
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Abstract

Asbestos cement sheets on building roofs and façades as well as asbestos cement water and sewerage pipes are the most frequently existing elements that contain asbestos in Poland. During removal from a specific building such a material automatically becomes hazardous waste. The presented paper covers studies carried out on leachability of pollutants from asbestos-containing waste, previously used for roofing. Laboratory tests under static conditions were carried out (1:10 test, pursuant to rules of the PN-EN 12457/1-4 standard) using distilled water as the leaching medium. Aluminium, boron, barium, cadmium, chromium, copper, iron, nickel, lead, strontium, zinc, and mercury were determined in the eluate. Low leachability of individual metals under the planned conditions was observed. In general, such metals as cadmium, nickel, lead, zinc, boron and mercury were not observed in solutions. The other analysed metals were observed in eluates, but their concentrations were usually low. The low leachability was found for barium (0.019 to 0.419 mg/dm3), chromium (0.019 to 0.095 mg/dm3), copper (0.006 to 0.019 mg/dm3), and iron (<0.01 to 0.017 mg/dm3). Increased leachability values were found only for strontium, between 0.267 and 4.530 mg/dm3, and aluminium, ranging from 0.603 to 3.270 mg/dm3. The analysed asbestos and cement materials feature a low percentage content of asbestos in flat and corrugated asbestos cement sheets (10–15%). Because of that it is possible to presume that pollutants characteristic of cement will be mainly present in products of leaching.
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Authors and Affiliations

Beata Klojzy-Karczmarczyk
1
ORCID: ORCID
Janusz Mazurek
1
ORCID: ORCID
Jarosław Staszczak
2
ORCID: ORCID

  1. Mineral and Energy Economy Research Institute of the Polish Academy of Sciences, Kraków, Poland
  2. Mineral and Energy Economy Research Institute, Polish Academy of Sciences, Kraków, Poland
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Abstract

Scarcity of fresh water resources is the major constraint for agricultural development in Iran as in many other regions with arid and semi-arid climate. With the pressure on fresh water resources, the use of un-conventional water resources including brackish, saline and sewage water has received greater attentions in recent years. The objective of this study was to assess the impact of farmers' practices using saline groundwater on wheat yield and soil salinity in a Mediterranean cli-mate of Fars province in southern Iran. The study was carried out in several commercial wheat production regions for two years. Chemical analysis of irrigation waters, volume of applied irrigation water, electrical conductivity of soil saturation extract (ECe) and yield were measured in each field. General information on agronomic practices was also collected using a questionnaire. Results demonstrate that waters with salinities higher than what has been classified as “suitable for irriga-tion” are being used for the production of wheat crop. Analysis of wheat yield response to saline irrigation water showed that for water salinities up to 10.7 mS∙cm–1 (threshold value) variation in yield was relatively minor, above which wheat yield decreased at a greater rate. Root zone salinity profiles showed the effect of winter rainfall in reducing soil salinity. It is concluded that although acceptable yields are obtained with some of the highly brackish waters, over application of these waters would threaten the sustainability of crop production in the region.

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Authors and Affiliations

Seyed A.M. Cheraghi
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Abstract

The recent decades have seen the growth in the fields of wireless communication technologies, which has made it possible to produce components with a rational cost of a few cubic millimeters of volume, called sensors. The collaboration of many of these wireless sensors with a basic base station gives birth to a network of wireless sensors. The latter faces numerous problems related to application requirements and the inadequate abilities of sensor nodes, particularly in terms of energy. In order to integrate the different models describing the characteristics of the nodes of a WSN, this paper presents the topological organization strategies to structure its communication. For large networks, partitioning into sub-networks (clusters) is a technique used to reduce consumption, improve network stability and facilitate scalability.
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Authors and Affiliations

Sarang Dagajirao Patil
1
Pravin Sahebrao Patil
2

  1. NES Gangamai College of Engineering, Nagaon, Dhule, Maharashta, India
  2. Dept. of E&C Engineering SSVPSBSD College of Engineering Dhule, Maharashtra, India
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Abstract

Thousands of low-power micro sensors make up Wireless Sensor Networks, and its principal role is to detect and report specified events to a base station. Due to bounded battery power these nodes are having very limited memory and processing capacity. Since battery replacement or recharge in sensor nodes is nearly impossible, power consumption becomes one of the most important design considerations in WSN. So one of the most important requirements in WSN is to increase battery life and network life time. Seeing as data transmission and reception consume the most energy, it’s critical to develop a routing protocol that addresses the WSN’s major problem. When it comes to sending aggregated data to the sink, hierarchical routing is critical. This research concentrates on a cluster head election system that rotates the cluster head role among nodes with greater energy levels than the others.We used a combination of LEACH and deep learning to extend the network life of the WSN in this study. In this proposed method, cluster head selection has been performed by Convolutional Neural Network (CNN). The comparison has been done between the proposed solution and LEACH, which shows the proposed solution increases the network lifetime and throughput.
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Authors and Affiliations

Hardik K Prajapati
1
Rutvij Joshi
2

  1. Gujarat Technological University, Ahmedabad, Gujarat, India
  2. Parul University, Vadodara, Gujarat, India
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Abstract

The cement production process is associated with the emission of dust. These are mainly CKD (cement kiln dust) and BPD (by-pass dust), classified as wastes from group 10 – Wastes from thermal processes, subgroups 10 and 13 – wastes from manufacture of cement, lime and plaster and articles and products made from them. Cement kiln dust is a waste of variable composition and properties, which makes it a difficult material to recover. The main directions of recovery presented in the world literature indicate the use of dust from cement kilns in cement, mortar and concrete production, the production of bricks and in order to improve soil quality and wastewater treatment. Factors affecting chemical and phase compositions of dust from cement kilns are the reason why each waste should be analyzed individually. The paper presents the results of the analysis of the cement kiln dust after dedusting cement kilns and two bypass dusts. Analysis of the chemical composition has shown significant concentrations of chlorine, potassium and calcium in all wastes. The content of: Si, S, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Zr, Pb, and Bi has also been confirmed. The analyzed dusts were characterized by the presence of carbonates (calcite, dolomite, and arcanite), quartz, alite, belite, sylvine, anhydrite, and portlandite in their phase composition. The leachates which were characterized by an alkaline reaction. In terms of leachability, high concentrations of chlorine ions in the analyzed dust leachates were confirmed, which significantly limits their use.

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Authors and Affiliations

Alicja Uliasz-Bocheńczyk

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