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The paper presents the overview of using the modification natural zeolites for heavy metals removal from aquatic environment. Zeolites occurred naturally as microporous materials. They are hydrated aluminosilicates with special ion-exchange and sorption properties. These minerals with special three-dimensional porous structure possess advantages over other cation exchange materials such as prize, the strong selectivity for different cations at low temperatures followed with loosen of non-toxic replaceable cations to the environment. Zeolites are used in many sectors of industry (filters for emission gases, waste water treatment, separators, ion exchange for softening water, catalysts for petroleum processing, organic synthesis and others). Modification of these minerals can be made by the various methods. They can be modified thermally or chemically. This work presents the treatment of zeolites by acid or bases treatment, inorganic salts and organic surfactants, which are adsorbed on the surface and lead to increasing of heavy metals removal efficiency. The results of these studies have shown that by these methods the efficiency of adsorption, selectivity, and catalytic properties of zeolite can be improved. [ABSTRACT FROM AUTHOR]

The analysis of bottom sediment quality is an important yet sensitive issue. The anthropological influences (i.e., urban, industrial and agricultural activities) as well as the natural processes (i.e., changes in precipitation amounts, erosion and weathering of crustal materials) degrade surface water quality and impair its use for drinking, industrial, agricultural, recreational and other purposes. Due to spatial and temporal variations in water chemistry, a monitoring program that provides a representative and reliable estimation of the quality of surface waters has become an important necessity. Heavy metals are usually present at low concentrations in aquatic environments but deposits of anthropogenic origin have raised their concentrations, causing environmental problems in rivers. This research was realised in order to determine and analyse selected heavy metals present in sediment samples from six river basin on East of Slovakia, representing by the rivers Hornad, Laborec, Torysa, Ondava, Topla and Poprad. Sampling points were selected based on the current surface water quality monitoring network. Investigation was focused on heavy metals (Zn, Cu, Pb, Cd, Ni, Hg, As, Fe, Mn). The content of heavy metals reflected the scale of industrial and mining activities in a particular locality. The degree of sediment contamination in the rivers and their comparison, has been evaluated using a Pollution load index. [ABSTRACT FROM AUTHOR]

The removal of sulphate ions from different types of wastewater is an environmental challenge faced by several industrial sectors, such as the mining, petrochemical or metallurgical industry. Sulphates and heavy metals represent one of the main pollution sources is industrial effluents such as acid mine drainage (AMD) and other mining effluents. Manufacturing processes, primarily mining activities, often result in the production of effluents containing high amounts of inorganic pollutants e.g. heavy metals or sulphates. AMD consists of an aqueous solution containing high metals and sulphate concentration, which impact surface and groundwater and lead to serious environmental problems. Low pH and high concentrations of heavy metals and sulphates are limiting for many various treatment technologies in these acidic waters. Currently used technologies for removal of inorganic compounds are result of a need by industry to achieve acceptable effluent quality standards set by the governments. These conventional and emerging treatment methods include precipitation, secondary co-precipitation, differential precipitation, ion exchange, membrane separation, evaporative recovery, reductive electrolysis, etc. Ion exchange is a very powerful technology where one or more undesirable contaminants are removed from water by exchange with another non-objectionable or less objectionable substance. A wide range of materials is available for the ion - exchange treatment, which are available in a variety of forms and have widely differing chemical and physical properties. The type of material to be used is selected based on its ability to remove impurities and undesirable ions and to control pH. Organic resins are often used for a number of treatment cycles with suitable solutions and then restoring the ion exchanger to its original ionic form before its reuse. Inorganic materials are commonly used for the treatment of liquid waste streams for which very high chemical cleanliness is not required. The paper deals with study of ion - exchange process under dynamic conditions for sulphate removal from acidic model solutions using ion - exchange resin with the aim to apply the results for treatment of acid mine drainage. [ABSTRACT FROM AUTHOR]

Sediments are usually regarded as the ultimate sink for heavy metals discharged into environment, and can be sensitive indicators for monitoring contaminants in aquatic environments. Therefore, the environmental problem of sediment pollution by heavy metals has received increasing attention in the last few decades in both developing and developed countries through the world. Environmental risk assessments, including sediment monitoring, are typical tools for supporting decision making in the regulatory context, and cover all kinds of spatial situations, from local to world-wide assessments, under very different regulatory contexts. This contribution provides an overview of the sediment management legislative. River sediment quality in the territory of East of Slovakia, representing the water basins of the rivers Hornad, Laborec, Poprad, Torysa, Ondava and Topla was investigated. Sampling points were selected based on the current surface water quality monitoring network. This study presents the results of pollutants concentration in sediments from the rivers on Eastern Slovakia and their comparison with worldwide legislation. [ABSTRACT FROM AUTHOR]

The contamination of aquatic and terrestrial ecosystems with heavy metals and other mining chemicals have been major environmental problems in many mining areas of the world. Industrial wastes, geochemical structure and metals mining form a potential source of metal contaminants in the aquatic environment especially in sediment. Pollution of the natural environment by heavy metals is a universal problem because of their undegradability. Transmission spectroscopy is the oldest and most commonly used method for identifying either organic or inorganic chemicals providing specific information on molecular structure, chemical bonding and molecular environment. It can be applied to study solids, liquids or gaseous samples being a powerful tool for qualitative and quantitative studies. From the IR absorption band or locations of the different peaks, the minerals were identified with the available literature. In addition to the band position, sharpness or diffuseness of bands helpful in the identification of mineral components. The IR study on sediment samples was highly useful in identifying the various minerals in sediment. This method was non-destructive and can be used in the identification of mineralogical composition. These results confirmed that applied technique is relatively quicker and more reliable in mineral analysis. The IR study on sediment samples was highly use. The paper deals with the study of sediment quality from different sampling sites from watersheds of East Slovakia using of XRF, FTIR and XRD analyses. [ABSTRACT FROM AUTHOR]

Sulphates are present in effluents of many industries, especially hydrometallurgy due to the widespread use of sulfuric acid in many processes and they are also the main anions in acid mine drainages that are product of sulphide oxidation. Sulphates are the contaminant with negative impact on water environment, therefore it should be removed from wastewater using an adequate process of treatment. Sulphates containing wastewaters or mine drainages are usually treated by a combination of operations including acidity neutralization, lime (or limestone) precipitation, reverse osmosis, electrodialysis and adsorption. The selection of the treatment process of such effluents is a function of many factors such as chemical availability, local regulations and process economics. Recent research has shown that biosorption by low cost biomass can also be an effective alternative. The paper deals with the sulphate removal from model solutions (initial concentration of sulphate ions 15 and 75 mg.L-1, respectively) by the natural biosorbents - wood sawdusts. Hornbeam sawdust had over 99 % efficiency for sulphate removal from model solution with initial concentration 15 mg.L-1. [ABSTRACT FROM AUTHOR]

The contamination of aquatic and terrestrial ecosystems with heavy metals and other mining chemicals have been major environmental problems in many mining areas of the world. Industrial wastes, geochemical structure and metals mining create a potential source of heavy metal pollution in the aquatic environment especially in sediment. Water reservoir Ruzin located in east Slovakia is one of the most contaminated sites by heavy metals originating from mining activity. Water reservoir Ruzin I. is situated in territory, which is well-known by its mining and metallurgical history for several centuries, such as ore deposit Smolnik. Surface water from this area is contaminated by acid mine drainage (AMD) outflowed from abandoned sulphide mine Smolnik. AMD with low value of the pH (about 3-4) is a result of chemical oxidation of sulphides and other chemical processes in mine. The pH increasing due to the mixture AMD with surface water is followed by metal precipitation and its sedimentation in water environment. Contaminated sediment is transported by erosion processes into the river Hnilec and then into water reservoir Ruzin. The data in this work were undergo several experimental procedures including statistical analyses, normalization and estimating anthropogenic impact factors to establish the concentration and identify the status of each heavy metal under investigation. The aim of this study was to evaluate the chemical quality of the sediment influenced by the mining activities from Smolnik creek through the Hnilec river until to water reservoir Ruzin I. by calculation of the enrichment factor, pollution load index and geoaccumulation index. [ABSTRACT FROM AUTHOR]

The occurrence of acid mine drainage is usually associated with mining activities. Acid mine drainage usually due to low pH (3-4) contains high concentrations of sulphates and heavy metals, and because of water pollution and devastation of the country can cause serious environmental problems. Depending on the hydrological characteristics of the region, it may affect a much larger area and can cause the deterioration of the quality parameters of surface and groundwater and the consequent threat to human health. According to Directive 2000/60/EC of the European Parliament it is necessary to ensure adequate water quality and protection of all water sources. In Slovak Republic, as the country with long mining traditions, now exist a few localities with existing acid mine drainage generation conditions (either in form of direct outflow from mine or leachate from tailing ponds). Low pH of these waters is limiting for many various treatment technologies and must be taken into consideration in the research of potential methods for acid mine drainage treatment. The presented paper deals with the utilisation of different substances for sulphates removal from model acidic solutions that imitate the conditions of acid mine drainage. Results of sorption experiments with surface modified silica and also precipitation using barium chloride and Portland cement are presented. [ABSTRACT FROM AUTHOR]

Aquatic sediment contaminated with heavy metals is still an unsolved problem in Europe. The problem is serious also in the Slovak water reservoirs. Water reservoir Ruzin located in east Slovakia (situated on the Hornad river) is one of the most contaminated sites by heavy metals coming from abandoned metallurgical mines produced acid mine drainage (AMD). These acidic waters, which frequently contain high concentrations of heavy metals, often have adverse effect on the quality and ecology of waters receiving the effluent. Bottom sediments in this reservoir are contaminated above all by heavy metals, which are alluvial into the reservoir from localities of former mining activities and thus they represent ecological load mainly at the inputs into reservoir. The large share of pollution is coming from the Hnilec catchment where is situated the abandoned mine Smolnik. The aim of this paper is assess the quality of sediments along its course from the source (Smolnik creek - Hnilec creek) to the mouth (reservoir Ruzin) based on the requirements of Slovak and EÚ legislation. Use of these tools can provide essential characterizations of key watershed sources, sensitive receptors, natural variation, and both natural and anthropogenic stressors. Only with these multiple tools and an understanding of their interactions can reliable determinations of sediment pollution and longterm consequences be made. Then cost-effective, environmentally protective management decisions can be made about the type, extent, and need for sediment remediation. [ABSTRACT FROM AUTHOR]

Waste water containing different types of heavy metal ions is being discharged from numerous sources and can cause several problems due to high toxicity and their solubility in the water. It is necessary to treat metal containing water before discharging into the environment. In recent years low-cost adsorbents are getting more and more popular. Their positives are low price, handling without further adjustment and in many cases these materials are based on waste or industrial by-products. On the other hand these simple materials exhibit worse sorption properties (specific surface area, sorption efficiency, etc.). Sorption of Cu(II) ions from model solution and acid mine drainage onto four types adsorbents has been investigated. As sorptive materials peat, hemp shives, commercial adsorbent SLOVAKITE and silica were used. The best sorption properties showed modified version of silica (SBA - 15_DTAP) modified by N1-(3-Trimethoxysilylpropyl)diethylenetriamine with 46.3 mg/g of adsorption capacity. From the research also resulted the positive influence of NaOH modification of hemp shives on Cu(II) removal efficiency. Overall this study shows that low-cost adsorbents are able to compete with more expensive synthetically prepared adsorbents. [ABSTRACT FROM AUTHOR]

Water quality monitoring has one of the highest priorities in environmental protection policy. The main objectives are to control and minimise the incidence of pollutant-oriented problems, and to provide water of appropriate quality to serve various purposes such as drinking water supply, irrigation water, etc. Pollution of the natural environment by heavy metals is a universal problem because these metals are indestructible and most of them have toxic effects on living organisms, when permissible concentration levels are exceeded. The degree of contamination in the the Smolnik creek, for the metals Ca, Mg, Fe, Mn, Al, Cu, Zn, As, Cd and Pb, has been evaluated using Enrichment factor (EF) and Pollution load index (PLI). Effect of heavy metals from mining activities in the Smolnik creek water evaluated using enrichment factor, present all indicators at deficiency to minimal enrichment to moderate enrichment. The content of sulphate in water show an extremely high enrichment in the water flow, it is represent as a high contamination of the water flow in Smolnik creek. Very high levels of pollution load index PLI (> 1) for both sampling sites are extremely high contamination with heavy metals. Declining value of PLI is due to dilution and spreading of heavy metals with distance from the source of contamination. [ABSTRACT FROM AUTHOR]

Sediment delivered from water erosion causes substantial waterway damages and water quality degradation. Characterization of bottom deposits is an important factor in the study of water quality because they are responsible for transporting a significant proportion of many contaminants, particularly nutrients. The valuable tools for assessment of the behaviour of chemicals in the environment are simulation models. Soil erosion models can simulate erosion processes in the watershed and may be able to take into account many of the complex interactions that affect rates of erosion. The aim of this paper is verification of the suggested model for prediction of nutrient concentrations in bottom sediment, which is carried out by statistical assessment of calculated concentrations and measured concentrations in small water basin Klusov, Slovakia, using t-test and F-test, at 0.05 significance level. [ABSTRACT FROM AUTHOR]

Manufacturing process, primarily mining activities, often result in the production of effluents containing high amounts of sulphate and heavy metals. These effluence are known as acid mine drainage (AMD) and is produced when sulphide - bearing material is exposed to oxygen and water. AMD usually due to low pH (2-5) contains high concentrations of inorganic pollutants (such as sulphates and heavy metals), which impact surface and groundwater. Consequently AMD prior to being released into the environment must be treated to meet government standards for the amount of inorganic pollutants contained in the water. Low pH is limiting for many various treatment technologies, including sorption. The paper deals with the study of two different methods (sorption and precipitation connected with oxidation) for heavy metals and sulphates removal from model acidic solutions [ABSTRACT FROM AUTHOR]

Aquatic sediments contaminated with heavy metals are still an unsolved problem in numerous industry sites in Europe. Water reservoir Ruzin located in east Slovakia is one of the most contaminated sites by heavy metals coming from mining and metallurgical industry. Mining activities are known to release significant amounts of toxic metals into the surrounding environment. The Ruzin water reservoir is situated in the Hornad River. The filling process of the reservoir began in 1969. During 40 years its volume was diminished by 10 million cubic meters. Bottom sediments are contaminated by heavy metals, namely Hg, Cu, Zn, Cd, Pb, Cr, Co, Sb and As which originate from the former mining activities e.g. locality Smolnik and represent the ecological loads mainly at the inputs into reservoir. This study presents the characterisation of the contaminated sediments from the water reservoir Ruzin by using of qualitative XRF analysis and FTIR method [ABSTRACT FROM AUTHOR]

Soil erosion associated with non-point source pollution is viewed as a process of land degradation in many terrestrial environments. The question of nutrient loading of rivers and reservoirs, as it relates to sediment in general and farmland erosion in particular, is still a potentially important issue. This paper presents the suggestion of model for predicting the total nitrogen, phosphorus and potassium contents in reservoir bottom sediments. The model is based on the soil loss calculation using the Universal Soil Loss Equation supplemented with determination of the average soil nutrient concentration in top soils, which depends on the nutrient input from fertilizer use and plant nutrient uptake. Verification of this suggested prediction model showed that the expected values of calculated and measured nutrient concentrations were not statistical significantly different and suggested model can be used for prediction the content of total nitrogen, phosphorus and potassium in reservoir bottom sediments. [ABSTRACT FROM AUTHOR]