Trihalomethanes (THM) and haloacetic acids (HAA) are the two important groups of disinfection by-... more Trihalomethanes (THM) and haloacetic acids (HAA) are the two important groups of disinfection by-products (DBPs) which are produced during the reaction between chlorine and natural organic matter. These substances are thought to be mutagenic and carcinogenic. In the present study, HAA, THM, and adsorbable organic halide (AOX) formation potentials in 29 reservoirs which are used as drinking water supply were
Waste management & research : the journal of the International Solid Wastes and Public Cleansing Association, ISWA, Jan 11, 2015
This study presents the options for source-segregation and selective collection of recyclable was... more This study presents the options for source-segregation and selective collection of recyclable waste fractions for Cetinje, Montenegro, with the aim of meeting the European Union 50% waste recycling target in 2023, and extending collection and disposal system that builds on the existing strengths of the city. To this end, three options were considered: (1) source separation and separate collection of dry recyclable materials and central sorting of residual waste; (2) source separation and collection of co-mingled dry recyclable materials, and central sorting in a clean material recovery facility of comingled recyclables and central sorting of residual waste; (3) collection of mixed waste (current situation) and subsequent central sorting. Scenarios 1 and 2 were found to meet the European Union 50% recycling target in 2023, provided that a fast implementation of the new separate collection schemes to fine sort the co-mingled collected recyclable materials is available. Finally, a fina...
Water science and technology : a journal of the International Association on Water Pollution Research, 2006
Landfilling is one of the most common methods that are used in the final disposal of sludge world... more Landfilling is one of the most common methods that are used in the final disposal of sludge world wide, as well as in Turkey. However, increasing sludge quantities and limited landfilling areas make this method difficult to apply. The use of sludge in agriculture presents a possible alternative for disposal. However, it also poses some risks to be evaluated. In this respect, it is important to identify the heavy metal content of sewage sludges because of its adverse health effects. This study aims to determine the heavy metal contents of sludges and wastewaters from three different wastewater treatment plants in Turkey. The selection of plants was carried out according to the different treatment technologies applied to wastewater and sludge in those plants. Heavy metal analysis of sludges and wastewaters was conducted using a microwave assisted digestion procedure. After sampling and analysis, the results show that all the related metal concentrations are below the values that are s...
Waste management & research : the journal of the International Solid Wastes and Public Cleansing Association, ISWA, 2014
Hazardous waste (HW) generation information is an absolute necessity for ensuring the proper plan... more Hazardous waste (HW) generation information is an absolute necessity for ensuring the proper planning, implementation, and monitoring of any waste management system. Unfortunately, environmental agencies in developing countries face difficulties in gathering data directly from the creators of such wastes. It is possible, however, to construct theoretical HW inventories using the waste generation factors (WGFs). The objective of this study was to develop a complete nationwide HW inventory of Turkey that relies on nation-specific WGFs to support management activities of the Turkish Ministry of Environment and Urbanization (MoEU). Inventory studies relied on WGFs from: (a) the literature and (b) field studies and analysis of waste declarations reflecting country-specific industrial practices. Moreover, new tools were introduced to the monitoring infrastructure of MoEU to obtain a comprehensive waste generation data set. Through field studies and a consideration of country specific cond...
The use of the white-rot fungus Polyporous versicolor in Ni(II) removal as biosorbent was investi... more The use of the white-rot fungus Polyporous versicolor in Ni(II) removal as biosorbent was investigated. Kinetic and isotherm sorption experiments were conducted to evaluate the effects of pH, time, temperature, and mixing intensity. Time-course variation of Ni(II) uptake at various temperatures (20, 25, and 35°C) and initial Ni(II) concentrations revealed that both the initial Ni(II) uptake rate and the Ni(II)
Reperfusion injury is a perplexing cause of early graft failure after lung transplantation and to... more Reperfusion injury is a perplexing cause of early graft failure after lung transplantation and today we know that reperfusion may be more harmful to tissues than the preceding ischemia. We hypothesized that administration of the nitric oxide donor nitroglycerin (NTG) during flush perfusion and reperfusion periods would ameliorate reperfusion-induced lung injury. Using an IN SITU normothermic ischemic lung rabbit model, three groups were studied (n = 7/group): (1) NTG given during flush perfusion (ischemia group); (2) NTG given in the flush perfusion and the reperfusion period (reperfusion group); and (3) no NTG (control group). All groups were flushed with low potassium dextran glucose solution. Blood gas analysis, tissue nitrite (nitric oxide metabolite) level analysis, bronchoalveolar lavage (BAL) fluid examination and morphological examinations were performed. Compared with the ischemia group, the reperfusion group had significantly improved arterial oxygenation (318 +/- 31.4 mmHg vs. 180 +/- 14.7 mmHg, P < 0.05), decreased BAL fluid neutrophil percentage (21 +/- 1.9 % vs. 30 +/- 5.6 %, P < 0.05), increased tissue nitrite level (32.55 +/- 4.12 nmol/g vs. 27.81 +/- 1.05 nmol/g, P < 0.05), and decreased tissue histopathological lesion scores (0.42 +/- 0.53 vs. 1.14 +/- 0.37, P < 0.05). This study suggests that nitric oxide donors supplemented during flush perfusion and reperfusion have more beneficial effects on lung functions against reperfusion injury than any other treatment modalities during IN SITU normothermic ischemic lung model.
Management of contaminated sites is a critical environmental issue around the world due to the hu... more Management of contaminated sites is a critical environmental issue around the world due to the human health risk involved for many sites and scarcity of funding. Moreover, clean-up costs of all contaminated sites to their background levels with existing engineering technologies may be financially infeasible and demand extended periods of operation time. Given these constraints, to achieve optimal utilization of available funds and prioritization of contaminated sites that need immediate attention, health-risk-based soil quality guidelines should be preferred over the traditional soil quality standards. For these reasons, traditional soil quality standards are being replaced by health-risk-based ones in many countries and in Turkey as well. The need for health-risk-based guidelines is clear, but developing these guidelines and implementation of them in contaminated site management is not a straightforward process. The goal of this study is to highlight the problems that are encountered at various stages of the development process of risk-based soil quality guidelines for Turkey and how they are dealt with. Utilization of different definitions and methodologies at different countries, existence of inconsistent risk assessment tools, difficulties in accessing relevant documents and reports, and lack of specific data required for Turkey are among these problems. We believe that Turkey's experience may help other countries that are planning to develop health-risk-based guidelines achieve their goals in a more efficient manner.
The MEDAWARE Project was initiated by the collaboration of 7 Med countries in 2003. The main aim ... more The MEDAWARE Project was initiated by the collaboration of 7 Med countries in 2003. The main aim of the project was to develop tools and guidelines for the promotion of the urban wastewater treatment and reuse in the agricultural production in the ...
This study aims at coupling of activated sludge treatment with nanofiltration to improve denim te... more This study aims at coupling of activated sludge treatment with nanofiltration to improve denim textile wastewater quality to reuse criteria. In the activated sludge reactor, the COD removal efficiency was quite high as it was 91+/-2% and 84+/-4% on the basis of total and soluble feed COD, respectively. The color removal efficiency was 75+/-10%, and around 50-70% of removed color was adsorbed on biomass or precipitated within the reactor. The high conductivity of the wastewater, as high as 8 mS/cm, did not adversely affect system performance. Although biological treatment is quite efficient, the wastewater does not meet the reuse criteria. Hence, further treatment to improve treated water quality was investigated using nanofiltration. Dead-end microfiltration (MF) with 5 microm pore size was applied to remove coarse particles before nanofiltration. The color rejection of nanofiltration was almost complete and permeate color was always lower than 10 Pt-Co. Similarly, quite high rejections were observed for COD (80-100%). Permeate conductivity was between 1.98 and 2.67 mS/cm (65% conductivity rejection). Wastewater fluxes were between 31 and 37 L/m2/h at 5.07 bars corresponding to around 45% flux declines compared to clean water fluxes. In conclusion, for denim textile wastewaters nanofiltration after biological treatment can be applied to meet reuse criteria.
This paper investigated the biodegradation kinetics of 4-chlorophenol (4-CP) and 2,4-dichlorophen... more This paper investigated the biodegradation kinetics of 4-chlorophenol (4-CP) and 2,4-dichlorophenol (2,4-DCP) separately in batch reactors and mixed in sequencing batch reactors (SBRs). Batch reactor experiments showed that both 4-CP and 2,4-DCP began to inhibit their own degradation at 53 and 25 mg l(-1), respectively, and that the Haldane equation gave a good fit to the experimental data because r(2) values were higher than 0.98. The maximum specific degradation rates (q(m)) were 130.3 and 112.4 mg g(-1) h for 4-CP and 2,4-DCP, respectively. The values of the half saturation (K(s)) and self-inhibition constants (K(i)) were 34.98 and 79.74 mg l(-1) for 4-CP, and 13.77 and 44.46 mg l(-1) for 2,4-DCP, respectively. The SBR was fed with a mixture of 220 mg l(-1) of 4-CP, 110 mg l(-1) of 2,4-DCP, and 300 mg l(-1) of peptone as biogenic substrate at varying feeding periods (0-8h) to evaluate the effect of feeding time on the performance of the SBR. During SBR operation, in addition to self-inhibition, 4-CP degradation was strongly and competitively inhibited by 2,4-DCP. The inhibitory effects were particularly pronounced during short feeding periods because of higher chlorophenol peak concentrations in the reactor. The competitive inhibition constant (K(ii)) of 2,4-DCP on 4-CP degradation was 0.17 mg l(-1) when the reactor was fed instantaneously (0 h feeding). During longer feedings, increased removal/loading rates led to lower chlorophenol peak concentrations at the end of feeding. Therefore, in multi-substrate systems feeding time plus reaction time should be determined based on both degradation kinetics and substrate interaction. During degradation, the meta cleavage of 4-chlorocatechol resulted in accumulation of a yellowish color because of the formation of 5-chloro-2-hydroxymuconic semialdehyde (CHMS), which was further metabolized. Isolation and enrichment of the chlorophenols-degrading culture suggested Pseudomonas sp. and Pseudomonas stutzeri to be the dominant species.
The task of rehabilitating the already existing waste treatment facilities of a sugar factory was... more The task of rehabilitating the already existing waste treatment facilities of a sugar factory was undertaken. A detailed survey of the water and wastewater streams indicated a necessity for immediate action towards water conservation within the plant. The spent waters from the beet-washing unit were first being intercepted at an integrated solids–liquid separation system (ISLSS) where they were partially recycled
Trihalomethanes (THM) and haloacetic acids (HAA) are the two important groups of disinfection by-... more Trihalomethanes (THM) and haloacetic acids (HAA) are the two important groups of disinfection by-products (DBPs) which are produced during the reaction between chlorine and natural organic matter. These substances are thought to be mutagenic and carcinogenic. In the present study, HAA, THM, and adsorbable organic halide (AOX) formation potentials in 29 reservoirs which are used as drinking water supply were
Waste management & research : the journal of the International Solid Wastes and Public Cleansing Association, ISWA, Jan 11, 2015
This study presents the options for source-segregation and selective collection of recyclable was... more This study presents the options for source-segregation and selective collection of recyclable waste fractions for Cetinje, Montenegro, with the aim of meeting the European Union 50% waste recycling target in 2023, and extending collection and disposal system that builds on the existing strengths of the city. To this end, three options were considered: (1) source separation and separate collection of dry recyclable materials and central sorting of residual waste; (2) source separation and collection of co-mingled dry recyclable materials, and central sorting in a clean material recovery facility of comingled recyclables and central sorting of residual waste; (3) collection of mixed waste (current situation) and subsequent central sorting. Scenarios 1 and 2 were found to meet the European Union 50% recycling target in 2023, provided that a fast implementation of the new separate collection schemes to fine sort the co-mingled collected recyclable materials is available. Finally, a fina...
Water science and technology : a journal of the International Association on Water Pollution Research, 2006
Landfilling is one of the most common methods that are used in the final disposal of sludge world... more Landfilling is one of the most common methods that are used in the final disposal of sludge world wide, as well as in Turkey. However, increasing sludge quantities and limited landfilling areas make this method difficult to apply. The use of sludge in agriculture presents a possible alternative for disposal. However, it also poses some risks to be evaluated. In this respect, it is important to identify the heavy metal content of sewage sludges because of its adverse health effects. This study aims to determine the heavy metal contents of sludges and wastewaters from three different wastewater treatment plants in Turkey. The selection of plants was carried out according to the different treatment technologies applied to wastewater and sludge in those plants. Heavy metal analysis of sludges and wastewaters was conducted using a microwave assisted digestion procedure. After sampling and analysis, the results show that all the related metal concentrations are below the values that are s...
Waste management & research : the journal of the International Solid Wastes and Public Cleansing Association, ISWA, 2014
Hazardous waste (HW) generation information is an absolute necessity for ensuring the proper plan... more Hazardous waste (HW) generation information is an absolute necessity for ensuring the proper planning, implementation, and monitoring of any waste management system. Unfortunately, environmental agencies in developing countries face difficulties in gathering data directly from the creators of such wastes. It is possible, however, to construct theoretical HW inventories using the waste generation factors (WGFs). The objective of this study was to develop a complete nationwide HW inventory of Turkey that relies on nation-specific WGFs to support management activities of the Turkish Ministry of Environment and Urbanization (MoEU). Inventory studies relied on WGFs from: (a) the literature and (b) field studies and analysis of waste declarations reflecting country-specific industrial practices. Moreover, new tools were introduced to the monitoring infrastructure of MoEU to obtain a comprehensive waste generation data set. Through field studies and a consideration of country specific cond...
The use of the white-rot fungus Polyporous versicolor in Ni(II) removal as biosorbent was investi... more The use of the white-rot fungus Polyporous versicolor in Ni(II) removal as biosorbent was investigated. Kinetic and isotherm sorption experiments were conducted to evaluate the effects of pH, time, temperature, and mixing intensity. Time-course variation of Ni(II) uptake at various temperatures (20, 25, and 35°C) and initial Ni(II) concentrations revealed that both the initial Ni(II) uptake rate and the Ni(II)
Reperfusion injury is a perplexing cause of early graft failure after lung transplantation and to... more Reperfusion injury is a perplexing cause of early graft failure after lung transplantation and today we know that reperfusion may be more harmful to tissues than the preceding ischemia. We hypothesized that administration of the nitric oxide donor nitroglycerin (NTG) during flush perfusion and reperfusion periods would ameliorate reperfusion-induced lung injury. Using an IN SITU normothermic ischemic lung rabbit model, three groups were studied (n = 7/group): (1) NTG given during flush perfusion (ischemia group); (2) NTG given in the flush perfusion and the reperfusion period (reperfusion group); and (3) no NTG (control group). All groups were flushed with low potassium dextran glucose solution. Blood gas analysis, tissue nitrite (nitric oxide metabolite) level analysis, bronchoalveolar lavage (BAL) fluid examination and morphological examinations were performed. Compared with the ischemia group, the reperfusion group had significantly improved arterial oxygenation (318 +/- 31.4 mmHg vs. 180 +/- 14.7 mmHg, P < 0.05), decreased BAL fluid neutrophil percentage (21 +/- 1.9 % vs. 30 +/- 5.6 %, P < 0.05), increased tissue nitrite level (32.55 +/- 4.12 nmol/g vs. 27.81 +/- 1.05 nmol/g, P < 0.05), and decreased tissue histopathological lesion scores (0.42 +/- 0.53 vs. 1.14 +/- 0.37, P < 0.05). This study suggests that nitric oxide donors supplemented during flush perfusion and reperfusion have more beneficial effects on lung functions against reperfusion injury than any other treatment modalities during IN SITU normothermic ischemic lung model.
Management of contaminated sites is a critical environmental issue around the world due to the hu... more Management of contaminated sites is a critical environmental issue around the world due to the human health risk involved for many sites and scarcity of funding. Moreover, clean-up costs of all contaminated sites to their background levels with existing engineering technologies may be financially infeasible and demand extended periods of operation time. Given these constraints, to achieve optimal utilization of available funds and prioritization of contaminated sites that need immediate attention, health-risk-based soil quality guidelines should be preferred over the traditional soil quality standards. For these reasons, traditional soil quality standards are being replaced by health-risk-based ones in many countries and in Turkey as well. The need for health-risk-based guidelines is clear, but developing these guidelines and implementation of them in contaminated site management is not a straightforward process. The goal of this study is to highlight the problems that are encountered at various stages of the development process of risk-based soil quality guidelines for Turkey and how they are dealt with. Utilization of different definitions and methodologies at different countries, existence of inconsistent risk assessment tools, difficulties in accessing relevant documents and reports, and lack of specific data required for Turkey are among these problems. We believe that Turkey's experience may help other countries that are planning to develop health-risk-based guidelines achieve their goals in a more efficient manner.
The MEDAWARE Project was initiated by the collaboration of 7 Med countries in 2003. The main aim ... more The MEDAWARE Project was initiated by the collaboration of 7 Med countries in 2003. The main aim of the project was to develop tools and guidelines for the promotion of the urban wastewater treatment and reuse in the agricultural production in the ...
This study aims at coupling of activated sludge treatment with nanofiltration to improve denim te... more This study aims at coupling of activated sludge treatment with nanofiltration to improve denim textile wastewater quality to reuse criteria. In the activated sludge reactor, the COD removal efficiency was quite high as it was 91+/-2% and 84+/-4% on the basis of total and soluble feed COD, respectively. The color removal efficiency was 75+/-10%, and around 50-70% of removed color was adsorbed on biomass or precipitated within the reactor. The high conductivity of the wastewater, as high as 8 mS/cm, did not adversely affect system performance. Although biological treatment is quite efficient, the wastewater does not meet the reuse criteria. Hence, further treatment to improve treated water quality was investigated using nanofiltration. Dead-end microfiltration (MF) with 5 microm pore size was applied to remove coarse particles before nanofiltration. The color rejection of nanofiltration was almost complete and permeate color was always lower than 10 Pt-Co. Similarly, quite high rejections were observed for COD (80-100%). Permeate conductivity was between 1.98 and 2.67 mS/cm (65% conductivity rejection). Wastewater fluxes were between 31 and 37 L/m2/h at 5.07 bars corresponding to around 45% flux declines compared to clean water fluxes. In conclusion, for denim textile wastewaters nanofiltration after biological treatment can be applied to meet reuse criteria.
This paper investigated the biodegradation kinetics of 4-chlorophenol (4-CP) and 2,4-dichlorophen... more This paper investigated the biodegradation kinetics of 4-chlorophenol (4-CP) and 2,4-dichlorophenol (2,4-DCP) separately in batch reactors and mixed in sequencing batch reactors (SBRs). Batch reactor experiments showed that both 4-CP and 2,4-DCP began to inhibit their own degradation at 53 and 25 mg l(-1), respectively, and that the Haldane equation gave a good fit to the experimental data because r(2) values were higher than 0.98. The maximum specific degradation rates (q(m)) were 130.3 and 112.4 mg g(-1) h for 4-CP and 2,4-DCP, respectively. The values of the half saturation (K(s)) and self-inhibition constants (K(i)) were 34.98 and 79.74 mg l(-1) for 4-CP, and 13.77 and 44.46 mg l(-1) for 2,4-DCP, respectively. The SBR was fed with a mixture of 220 mg l(-1) of 4-CP, 110 mg l(-1) of 2,4-DCP, and 300 mg l(-1) of peptone as biogenic substrate at varying feeding periods (0-8h) to evaluate the effect of feeding time on the performance of the SBR. During SBR operation, in addition to self-inhibition, 4-CP degradation was strongly and competitively inhibited by 2,4-DCP. The inhibitory effects were particularly pronounced during short feeding periods because of higher chlorophenol peak concentrations in the reactor. The competitive inhibition constant (K(ii)) of 2,4-DCP on 4-CP degradation was 0.17 mg l(-1) when the reactor was fed instantaneously (0 h feeding). During longer feedings, increased removal/loading rates led to lower chlorophenol peak concentrations at the end of feeding. Therefore, in multi-substrate systems feeding time plus reaction time should be determined based on both degradation kinetics and substrate interaction. During degradation, the meta cleavage of 4-chlorocatechol resulted in accumulation of a yellowish color because of the formation of 5-chloro-2-hydroxymuconic semialdehyde (CHMS), which was further metabolized. Isolation and enrichment of the chlorophenols-degrading culture suggested Pseudomonas sp. and Pseudomonas stutzeri to be the dominant species.
The task of rehabilitating the already existing waste treatment facilities of a sugar factory was... more The task of rehabilitating the already existing waste treatment facilities of a sugar factory was undertaken. A detailed survey of the water and wastewater streams indicated a necessity for immediate action towards water conservation within the plant. The spent waters from the beet-washing unit were first being intercepted at an integrated solids–liquid separation system (ISLSS) where they were partially recycled
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