The food industry wastewater is known to present a high organic matter content, due to specific raw materials and processing activities. Even if these compounds are not directly toxic to the environment, high concentrations in effluents could represent a source of pollution as discharges of high biological oxygen demand may impact receiving river's ecosystems. Identifying the main organic contaminants in wastewater samples represents the first step in establishing the optimum treatment method. The sample analysis for the non-target compounds through the GC-MS technique highlights, along with other analytical parameters, the efficiency of the main physical and biological treatment steps of the middle-size Wastewater Treatment Plant (WWTP). Long-chain fatty acids and their esters were the main abundant classes of non-target identified compounds. The highest intensity detection signal was reached by n-hexadecanoic acid or palmitic acid, a component of palm oil, after the physical treatment processes with dissolved air flotation, and by 1-octadecanol after biological treatment.
{"title":"Short investigation on occurrence and removal of semivolatiles during wastewater treatment processes","authors":"Maria Diana Puiu","doi":"10.21698/rjeec.2021.216","DOIUrl":"https://doi.org/10.21698/rjeec.2021.216","url":null,"abstract":"The food industry wastewater is known to present a high organic matter content, due to specific raw materials and processing activities. Even if these compounds are not directly toxic to the environment, high concentrations in effluents could represent a source of pollution as discharges of high biological oxygen demand may impact receiving river's ecosystems. Identifying the main organic contaminants in wastewater samples represents the first step in establishing the optimum treatment method. The sample analysis for the non-target compounds through the GC-MS technique highlights, along with other analytical parameters, the efficiency of the main physical and biological treatment steps of the middle-size Wastewater Treatment Plant (WWTP). Long-chain fatty acids and their esters were the main abundant classes of non-target identified compounds. The highest intensity detection signal was reached by n-hexadecanoic acid or palmitic acid, a component of palm oil, after the physical treatment processes with dissolved air flotation, and by 1-octadecanol after biological treatment.","PeriodicalId":21370,"journal":{"name":"Romanian Journal of Ecology & Environmental Chemistry","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83037301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Complex studies were performed combining macroscopic and biochemical analyzes of selected biomonitors, exposed in exposure systems outdoor with mixtures of pollutants as well as controlled exposure with certain concentrations of pollutants in fumigation chambers. In this study, the following plant species were used as bioindicators: Nicotiana tabacum, Petunia hybrida, Ricinus comunis, Trifolium pretense. The exposure plant samples were compared with control samples of biomonitors maintained under standardized conditions in the climate chamber. Classical methods of biochemistry combined with those of exposure biomonitoring have led to the completion of knowledge about the ways of action of plants to pollution. The analysis of some of the antioxidant compounds that are representing a structural class of chemicals (enzymes) with a wide range of biological functions, with the role of free radical inhibition, was performed. Many of the constituent compounds in certain cell types, also called active compounds, in this case, polyphenols are present in the body of some plant species. Polyphenol's presence in organisms, that are not usually present or are in normal quantities, is caused by stress, (pollution being a stress factor). Large amounts of polyphenols in plants are also given by the presence of pollutants in the environment. Through these extensive combined studies, it has been demonstrated that pollution can be a degenerative factor at the biochemical and physiological level, at the plant tissue level, with irreversible effects.
{"title":"Exposure assessment using biomonitoring","authors":"A. Cozea, G. Tanase, M. Neagu","doi":"10.21698/rjeec.2021.211","DOIUrl":"https://doi.org/10.21698/rjeec.2021.211","url":null,"abstract":"Complex studies were performed combining macroscopic and biochemical analyzes of selected biomonitors, exposed in exposure systems outdoor with mixtures of pollutants as well as controlled exposure with certain concentrations of pollutants in fumigation chambers. In this study, the following plant species were used as bioindicators: Nicotiana tabacum, Petunia hybrida, Ricinus comunis, Trifolium pretense. The exposure plant samples were compared with control samples of biomonitors maintained under standardized conditions in the climate chamber. Classical methods of biochemistry combined with those of exposure biomonitoring have led to the completion of knowledge about the ways of action of plants to pollution. The analysis of some of the antioxidant compounds that are representing a structural class of chemicals (enzymes) with a wide range of biological functions, with the role of free radical inhibition, was performed. Many of the constituent compounds in certain cell types, also called active compounds, in this case, polyphenols are present in the body of some plant species. Polyphenol's presence in organisms, that are not usually present or are in normal quantities, is caused by stress, (pollution being a stress factor). Large amounts of polyphenols in plants are also given by the presence of pollutants in the environment. Through these extensive combined studies, it has been demonstrated that pollution can be a degenerative factor at the biochemical and physiological level, at the plant tissue level, with irreversible effects.","PeriodicalId":21370,"journal":{"name":"Romanian Journal of Ecology & Environmental Chemistry","volume":"57 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81476181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ecaterina Anca Serban, G. Vasile, S. Gheorghe, C. Stoica, G. Catrina, C. Dinu
The paper presents an experimental laboratory study of the bioaccumulation of the toxic metal arsenic in the medicinal plant chamomile (Matricaria Chamomilla L.). The study makes a comparison regarding the bioaccumulation capacity of the chamomile plant in which arsenic is found as a unique contaminant, as well as in mixtures of 2, 3, or 4 toxic metals (Cd, Ni and Pb) on a natural soil enriched with metals, compared to the chamomile plant developed on an unpolluted substrate. The tests followed the effects of soil pollution with metals on the germination and development of chamomile. The experimental results indicated that arsenic does not bioaccumulate in the chamomile plant, remaining in the soil. The experiment that was an exception is the one with arsenic as the only contaminant (E1) in which at 90 days, the arsenic content in the chamomile plant was 3.58 mg/kg arsenic, the value that is within normal limits, below the phytotoxic value of 5 mg/kg, but was higher than that determined in the plant from the control test experiment (<0.75 mg/kg). The bioaccumulation factor (BCF) after 90 days, in all experiments, either by a combination of metals or a single contaminant had values lower than 1, indicating that the plant does not accumulate arsenic. The total chlorophyll from the results obtained indicates that the toxicity in the E1 experiment is higher than in the metal mixture.
{"title":"The effect of toxic metal As on the Matricaria Chamomilla L. medicinal plant","authors":"Ecaterina Anca Serban, G. Vasile, S. Gheorghe, C. Stoica, G. Catrina, C. Dinu","doi":"10.21698/rjeec.2021.219","DOIUrl":"https://doi.org/10.21698/rjeec.2021.219","url":null,"abstract":"The paper presents an experimental laboratory study of the bioaccumulation of the toxic metal arsenic in the medicinal plant chamomile (Matricaria Chamomilla L.). The study makes a comparison regarding the bioaccumulation capacity of the chamomile plant in which arsenic is found as a unique contaminant, as well as in mixtures of 2, 3, or 4 toxic metals (Cd, Ni and Pb) on a natural soil enriched with metals, compared to the chamomile plant developed on an unpolluted substrate. The tests followed the effects of soil pollution with metals on the germination and development of chamomile. The experimental results indicated that arsenic does not bioaccumulate in the chamomile plant, remaining in the soil. The experiment that was an exception is the one with arsenic as the only contaminant (E1) in which at 90 days, the arsenic content in the chamomile plant was 3.58 mg/kg arsenic, the value that is within normal limits, below the phytotoxic value of 5 mg/kg, but was higher than that determined in the plant from the control test experiment (<0.75 mg/kg). The bioaccumulation factor (BCF) after 90 days, in all experiments, either by a combination of metals or a single contaminant had values lower than 1, indicating that the plant does not accumulate arsenic. The total chlorophyll from the results obtained indicates that the toxicity in the E1 experiment is higher than in the metal mixture.","PeriodicalId":21370,"journal":{"name":"Romanian Journal of Ecology & Environmental Chemistry","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87838957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Birch ssp. in the sub-Carpathians curvature can be found in composition with beech and other resinous species, unevenly distributed from the mountain peaks at around 1200 m down to 500-600, mainly from high hills to depressions at 600m, rarely seen on plain sites, crossing different geomorphological structures and overall accounting for 3857.1 ha. The main objective of the paper was to analyze the site and stand characteristics of Betula pendula ssp. Roth. in the subCarpathians curvature as followed: stand structure, stand types and stand site types, soils and different metrics, from growth to yields and its connectivity.The ecological adaptability to climate and soil and early fast growth, makes silver birch fulfill the overall requirements as a pioneer species, mostly naturally regenerated. Birch distribution is highly influenced by stand structure having low proportion in compositions, mean height of 15 m at age 50, and a diameter of 20m. Regarding the site, characteristics are more commonly found on fertile soils, corrugated or fragmented site type with a slope of 20-50° and it is distributed as secondary species in stands, averaging 750m in attitude, ranging from 500 to 1200m, 90% being in mixtures with other species with a mean annual increment of approximately 7 m³/year/ha regardless of stand site type. As an early successional species, it serves as a first colonizer but secondary species and quite often as an ecological instrument to improve the soil characteristics, biodiversity and prevent landslides in certain sites, lacking economic value other than fuel wood or other non-wood products.
{"title":"Betula pendula Ssp. distribution and growth in the sub-Carpathian curvature","authors":"Mihai Harpa, L. Dincă","doi":"10.21698/rjeec.2021.202","DOIUrl":"https://doi.org/10.21698/rjeec.2021.202","url":null,"abstract":"Birch ssp. in the sub-Carpathians curvature can be found in composition with beech and other resinous species, unevenly distributed from the mountain peaks at around 1200 m down to 500-600, mainly from high hills to depressions at 600m, rarely seen on plain sites, crossing different geomorphological structures and overall accounting for 3857.1 ha. The main objective of the paper was to analyze the site and stand characteristics of Betula pendula ssp. Roth. in the subCarpathians curvature as followed: stand structure, stand types and stand site types, soils and different metrics, from growth to yields and its connectivity.The ecological adaptability to climate and soil and early fast growth, makes silver birch fulfill the overall requirements as a pioneer species, mostly naturally regenerated. Birch distribution is highly influenced by stand structure having low proportion in compositions, mean height of 15 m at age 50, and a diameter of 20m. Regarding the site, characteristics are more commonly found on fertile soils, corrugated or fragmented site type with a slope of 20-50° and it is distributed as secondary species in stands, averaging 750m in attitude, ranging from 500 to 1200m, 90% being in mixtures with other species with a mean annual increment of approximately 7 m³/year/ha regardless of stand site type. As an early successional species, it serves as a first colonizer but secondary species and quite often as an ecological instrument to improve the soil characteristics, biodiversity and prevent landslides in certain sites, lacking economic value other than fuel wood or other non-wood products.","PeriodicalId":21370,"journal":{"name":"Romanian Journal of Ecology & Environmental Chemistry","volume":"252 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83494899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The developed method of determining KS from pH metric data has a number of advantages compared to those used traditionally. First, in place of the residual concentrations of the salt components, only the pH value of the saturated solution is used in the derived expressions. Thus, the number of independent variables, which need to be measured experimentally, is reduced. Furthermore, the potentiometric method, used to determine the pH, is sufficiently accurate, simple and universal and does not necessitate the use of ion-selective electrodes. At the same time, the residual concentrations are usually measured by chemical methods, which are inferior in most cases, for several reasons, compared to the potentiometric method. Second, the KS value calculated by the developed method has a thermodynamic character. The organization of the experiment must be appropriate to the applied equations. Therefore, it is necessary to draw attention to the need for high accuracy in the process of preparing the initial solutions, because the initial concentrations of the precipitate components are included in the calculation formulas. The developed method for determining Ks can be applied for systems of any degree of complexity, which contain additional complexing agents.
{"title":"pH-metric method determining the solubility and solubility products of slightly soluble salts of arbitrary composition","authors":"I. Povar, O. Spînu, B. Pintilie","doi":"10.21698/rjeec.2021.208","DOIUrl":"https://doi.org/10.21698/rjeec.2021.208","url":null,"abstract":"The developed method of determining KS from pH metric data has a number of advantages compared to those used traditionally. First, in place of the residual concentrations of the salt components, only the pH value of the saturated solution is used in the derived expressions. Thus, the number of independent variables, which need to be measured experimentally, is reduced. Furthermore, the potentiometric method, used to determine the pH, is sufficiently accurate, simple and universal and does not necessitate the use of ion-selective electrodes. At the same time, the residual concentrations are usually measured by chemical methods, which are inferior in most cases, for several reasons, compared to the potentiometric method. Second, the KS value calculated by the developed method has a thermodynamic character. The organization of the experiment must be appropriate to the applied equations. Therefore, it is necessary to draw attention to the need for high accuracy in the process of preparing the initial solutions, because the initial concentrations of the precipitate components are included in the calculation formulas. The developed method for determining Ks can be applied for systems of any degree of complexity, which contain additional complexing agents.","PeriodicalId":21370,"journal":{"name":"Romanian Journal of Ecology & Environmental Chemistry","volume":"116 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72932898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, original methods for determining such thermodynamic characteristics as solubility K S0 product (KS) or the activity product ( )of slightly soluble hydroxides and acids are communicated. Developed methods for determining KS and solubility S are based only on the pH values of the saturated aqueous solution for a known initial composition of the heterogeneous mixture and the equilibrium constants of an arbitrary set of possible side reactions in the aqueous natural systems. The determination of solubility S and solubility product KS is also possible in the presence of other hydroxides or acids of known concentrations. Deduced equations allow the calculation of such characteristics, as the equilibrium concentrations of the components of slightly soluble compounds in aqueous phase and the degree of precipitation γ of the solid phase for various initial concentrations of the components of the heterogeneous mixture which are known in the process of preparing the mixture, requiring only experimental pH values of a saturated solution. From the known experimental pH data, S and KS were calculated for a series of hydroxides and acids of arbitrary composition. The obtained results correlated well with the known tabular values. Analysis of a number of real systems illustrated the deduced expressions, including calculations and theoretical explanations.
{"title":"pH-metric method for determining the solubility and solubility products of slightly soluble hydroxides and acids","authors":"I. Povar, O. Spînu, B. Pintilie","doi":"10.21698/rjeec.2021.204","DOIUrl":"https://doi.org/10.21698/rjeec.2021.204","url":null,"abstract":"In this paper, original methods for determining such thermodynamic characteristics as solubility K S0 product (KS) or the activity product ( )of slightly soluble hydroxides and acids are communicated. Developed methods for determining KS and solubility S are based only on the pH values of the saturated aqueous solution for a known initial composition of the heterogeneous mixture and the equilibrium constants of an arbitrary set of possible side reactions in the aqueous natural systems. The determination of solubility S and solubility product KS is also possible in the presence of other hydroxides or acids of known concentrations. Deduced equations allow the calculation of such characteristics, as the equilibrium concentrations of the components of slightly soluble compounds in aqueous phase and the degree of precipitation γ of the solid phase for various initial concentrations of the components of the heterogeneous mixture which are known in the process of preparing the mixture, requiring only experimental pH values of a saturated solution. From the known experimental pH data, S and KS were calculated for a series of hydroxides and acids of arbitrary composition. The obtained results correlated well with the known tabular values. Analysis of a number of real systems illustrated the deduced expressions, including calculations and theoretical explanations.","PeriodicalId":21370,"journal":{"name":"Romanian Journal of Ecology & Environmental Chemistry","volume":"145 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80990570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Pirvu, I. Paun, M. Niculescu, V. Iancu, L. Pascu, F. Chiriac
Water resources crisis can lead to a new concept of wastewater treatment. Wastewater cannot be considered waste but can be a renewable or non-renewable energy source. Nutrients from wastewater could be recycled and not disposed of. A circular economy can be created that can be based on the ability of algae to absorb and store nutrients: carbon (C), nitrogen (N) and phosphorus (P). This study investigates the stoichiometry between carbon, nitrogen and phosphorus in wastewater from three geographical regions of Romania. The concentrations of inorganic nitrogen, total nitrogen, total phosphorus, and total organic carbon were compared and evaluated. Three wastewater sampling points located in different areas were monitored, in the period 2013-2017 for the sampling point located in the central-northern part of the Romanian Plain and in the period 2015-2017 for the other two studied areas. The obtained results showed very high values of total nitrogen concentrations with values between 28.2 mg/L and 107.2 mg/L for the southeastern part of Romania. The values of the stoichiometric ratio’s C/N, C/P, N/P have varied over time with maximums in the autumn and winter seasons which indicates the existence of significant contamination of wastewater. It may be possible in the future to improve the performance of wastewater treatment by adjusting C, N, and P parameters.
{"title":"Stoichiometry of carbon, nitrogen and phosphorus in wastewater from Romania","authors":"F. Pirvu, I. Paun, M. Niculescu, V. Iancu, L. Pascu, F. Chiriac","doi":"10.21698/rjeec.2021.215","DOIUrl":"https://doi.org/10.21698/rjeec.2021.215","url":null,"abstract":"Water resources crisis can lead to a new concept of wastewater treatment. Wastewater cannot be considered waste but can be a renewable or non-renewable energy source. Nutrients from wastewater could be recycled and not disposed of. A circular economy can be created that can be based on the ability of algae to absorb and store nutrients: carbon (C), nitrogen (N) and phosphorus (P). This study investigates the stoichiometry between carbon, nitrogen and phosphorus in wastewater from three geographical regions of Romania. The concentrations of inorganic nitrogen, total nitrogen, total phosphorus, and total organic carbon were compared and evaluated. Three wastewater sampling points located in different areas were monitored, in the period 2013-2017 for the sampling point located in the central-northern part of the Romanian Plain and in the period 2015-2017 for the other two studied areas. The obtained results showed very high values of total nitrogen concentrations with values between 28.2 mg/L and 107.2 mg/L for the southeastern part of Romania. The values of the stoichiometric ratio’s C/N, C/P, N/P have varied over time with maximums in the autumn and winter seasons which indicates the existence of significant contamination of wastewater. It may be possible in the future to improve the performance of wastewater treatment by adjusting C, N, and P parameters.","PeriodicalId":21370,"journal":{"name":"Romanian Journal of Ecology & Environmental Chemistry","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85214287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coagulation-flocculation is an important step for the treatment of drinking water obtained from surface water sources. Various types of flocculants are available in the drinking water treatment market but only some of them are friendly for the environment due to their specific structure, which includes natural compounds. Starch-based flocculants are included in this category and some types of them were tested in our research work, in similar conditions with ordinary polyelectrolytes, in order to prove their efficiencies for turbidity and organic load (COD-Mn) removal. Five types of flocculants based on starch and acrylamide were tested during the classic treatment flow coagulation-flocculation-settling with aluminum sulfate as coagulant (1-10 mg Al/L) and 0.5-10 mL/L flocculant dose (0.2% active substance). Better removal efficiencies of turbidity and organic load (COD-Mn) in case of flocculants based on starch and acrylamide copolymers: over 99% for turbidity and ~90% for COD-Mn in case of 300-400 NTU initial surface water turbidity were registered.
{"title":"Environmental friendly flocculants for drinking water treatment","authors":"M. Ștefănescu, L. Dinu, C. Bumbac","doi":"10.21698/rjeec.2021.106","DOIUrl":"https://doi.org/10.21698/rjeec.2021.106","url":null,"abstract":"Coagulation-flocculation is an important step for the treatment of drinking water obtained from surface water sources. Various types of flocculants are available in the drinking water treatment market but only some of them are friendly for the environment due to their specific structure, which includes natural compounds. Starch-based flocculants are included in this category and some types of them were tested in our research work, in similar conditions with ordinary polyelectrolytes, in order to prove their efficiencies for turbidity and organic load (COD-Mn) removal. Five types of flocculants based on starch and acrylamide were tested during the classic treatment flow coagulation-flocculation-settling with aluminum sulfate as coagulant (1-10 mg Al/L) and 0.5-10 mL/L flocculant dose (0.2% active substance). Better removal efficiencies of turbidity and organic load (COD-Mn) in case of flocculants based on starch and acrylamide copolymers: over 99% for turbidity and ~90% for COD-Mn in case of 300-400 NTU initial surface water turbidity were registered.","PeriodicalId":21370,"journal":{"name":"Romanian Journal of Ecology & Environmental Chemistry","volume":"104 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84810186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Catrina, B. Stanescu, A. Serbanescu, Georgiana Cernica, Lidia Kim
Long-term landfilling of hazardous waste should be a careful choice for any producer or generator of waste, as the behavior of the waste is different due to the physical-chemical conditions or following contact with other hazardous waste. In this study, the research undertaken was aimed at developing an experimental method for the assessment and characterization of hazardous waste for long-term storage. The method consists in the assessment of the behavior of heavy metals from waste, under different leaching conditions. To study various hazardous wastes, fly ash from the incineration of medical waste and slag from aluminum casting were chosen. Contact time, pH and redox potential are important parameters in the leaching process. The solubility of metals increases at pH values between 2 - 5 pH units and decreases at pH values between 6-12 pH units. The highest solubility of metals (As, Cr, Cu, Ni, Pb and Zn) in the tested waste was obtained after 48 hours at pH values between 2 - 5 pH units. Also, the values of the redox potential decrease almost linearly as the pH value increases. The developed method is a useful tool to assess the behavior of hazardous waste for long-term storage in landfills for this category of wastes.
{"title":"Experimental method for the assessment and characterization of hazardous waste for long-term storage","authors":"G. Catrina, B. Stanescu, A. Serbanescu, Georgiana Cernica, Lidia Kim","doi":"10.21698/rjeec.2021.103","DOIUrl":"https://doi.org/10.21698/rjeec.2021.103","url":null,"abstract":"Long-term landfilling of hazardous waste should be a careful choice for any producer or generator of waste, as the behavior of the waste is different due to the physical-chemical conditions or following contact with other hazardous waste. In this study, the research undertaken was aimed at developing an experimental method for the assessment and characterization of hazardous waste for long-term storage. The method consists in the assessment of the behavior of heavy metals from waste, under different leaching conditions. To study various hazardous wastes, fly ash from the incineration of medical waste and slag from aluminum casting were chosen. Contact time, pH and redox potential are important parameters in the leaching process. The solubility of metals increases at pH values between 2 - 5 pH units and decreases at pH values between 6-12 pH units. The highest solubility of metals (As, Cr, Cu, Ni, Pb and Zn) in the tested waste was obtained after 48 hours at pH values between 2 - 5 pH units. Also, the values of the redox potential decrease almost linearly as the pH value increases. The developed method is a useful tool to assess the behavior of hazardous waste for long-term storage in landfills for this category of wastes.","PeriodicalId":21370,"journal":{"name":"Romanian Journal of Ecology & Environmental Chemistry","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85266069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Neidoni, V. Nicorescu, Ladislau Andres, S. Negrea, L. A. Diaconu
This paper presents the ecological state of large areas of the Bega and Timis River basins, evaluated based on physical-chemical parameters of water samples in relation to the anthropogenic sources of pollution that occur along these rivers. For the monitoring program, twelve sampling points on the Bega and ten sampling points on the Timis were established in order to determine surface water quality. The potential sources of pollution were highlighted by a downstream vs. upstream analysis. Ecological conditions have been assessed taking into account the national legislation, which transposes the Water Framework Directive on promoting the sustainable use of water based on the long-term protection of water resources. The main sources of pollution were related to the discharges from localities and industry, but the current ecological status of the two water bodies analyzed is in a relatively good state.
{"title":"Database with pollution sources and impact assessment in Bega and Timis River basins","authors":"D. Neidoni, V. Nicorescu, Ladislau Andres, S. Negrea, L. A. Diaconu","doi":"10.21698/rjeec.2021.104","DOIUrl":"https://doi.org/10.21698/rjeec.2021.104","url":null,"abstract":"This paper presents the ecological state of large areas of the Bega and Timis River basins, evaluated based on physical-chemical parameters of water samples in relation to the anthropogenic sources of pollution that occur along these rivers. For the monitoring program, twelve sampling points on the Bega and ten sampling points on the Timis were established in order to determine surface water quality. The potential sources of pollution were highlighted by a downstream vs. upstream analysis. Ecological conditions have been assessed taking into account the national legislation, which transposes the Water Framework Directive on promoting the sustainable use of water based on the long-term protection of water resources. The main sources of pollution were related to the discharges from localities and industry, but the current ecological status of the two water bodies analyzed is in a relatively good state.","PeriodicalId":21370,"journal":{"name":"Romanian Journal of Ecology & Environmental Chemistry","volume":"26 3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83538327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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