Madencilik endüstrisi modern toplumun gelişmesinde rol oynayan en önemli endüstriyel faaliyetleri... more Madencilik endüstrisi modern toplumun gelişmesinde rol oynayan en önemli endüstriyel faaliyetlerinden biri olmakla birlikte dünyanın en büyük atık üreten endüstrisidir. Gelişen teknoloji ve endüstriyel faaliyetlerin ihtiyacı olan hammaddelerin madencilik faaliyetleri ile doğal kaynaklardan elde edilmesi, biyolojik çeşitliliğin yok edilmesine ve çevre kirliliği sorunlarına neden olabilmektedir. Madencilik faaliyetlerinden vazgeçilmesi mümkün olmadığına göre, madenlerin çıkartılmasında kamu yararının yanında doğal kaynakların korunması ve çevre kirliliği oluşturmaması konusunda da daha duyarlı olunmalı ve uygun bertaraf yöntemleri için çeşitli mühendislik tekniklerinin uygulanması hedeflenmelidir. Madencilik faaliyetleri sonucu oluşan atıklardan olan çamur genel olarak arazilerde (atık barajlarında veya atık döküm sahalarında) depolanarak bertaraf edilmektedir. Bu depolama alanlarında ise asit maden drenajı (sülfit oksidasyonundan dolayı), geoteknik stabilite ve diğer bazı sebeplerden dolayı çevresel sorunlar meydana gelebilmektedir. Yerüstü atık barajları depolama alanlarında oluşan olumsuz nedenlerden dolayı maden atığı çamurların sucul alıcı ortamlarda bertarafı, özellikle sabit indirgeme koşulları altında ve sülfit minerallerinin jeokimyasal olarak istikrarlı olduğu derin deniz altlarında bertarafı bir seçenek olarak görülebilir. Bu çalışmada, maden atıklarının ve maden cevheri zenginleştirme atıklarından olan sulu çamurun (maden atık çamurunun) genel bertaraf yöntemleri, özellikle denizaltına deşarj ve denizaltında depolama yöntemi incelenmiştir. Bu yöntemin olası olumlu/olumsuz çevresel etkileri tartışılmıştır. Türkiye'de bulunan maden atığı çamuru derin denizaltı depolama (Karadeniz için) tesisi ve bu deşarjın (yöntemin) etkilerini belirlemek için yapılan deneysel çalışmalar değerlendirilmiştir. Bu kapsamda yapılan deneysel çalışmalar değerlendirildiğinde, derin deniz deşarjı tesisiyle Karadeniz'e deşarj edilen maden atık çamurlarının denizin tabanına doğru hareket eden bir atık olduğu (negatif yüzerliliğe sahip veya batan atık), anoksik bölgeden oksijenli bölgeye yükselemediği belirlenmiştir.
Polyacrylic acid diallyl dimethyl ammonium chloride (AAC-Dadmac) hydrogel was used as adsorbent f... more Polyacrylic acid diallyl dimethyl ammonium chloride (AAC-Dadmac) hydrogel was used as adsorbent for the removal of heavy metals (Cu(II), Ni(II), Zn(II) and total Cr) from electroplating wastewater. The effects of hydrogel dosage, contact time and shaking speed on heavy metal removal from electroplating wastewater were studied in a batch system. The equilibrium adsorption isotherm of heavy metals on the AAC-Dadmac hydrogel was studied using Langmuir and Freundlich isotherm models. The adsorption equilibrium data fitted well to the Langmuir isotherm model. The maximum adsorption capacities, q m (mg/g), of the AAC-Dadmac hydrogel for Cu(II), Ni(II), Zn(II) and total Cr were 2.336, 0.960, 5.319, and 4.608 mg/g, respectively. Kinetics of adsorption was found to follow the pseudo-second-order rate equation. The results showed that the AAC-Dadmac hydrogel can be used as an alternative adsorbent for the removal of heavy metal ions from electroplating wastewater.
In this study, effects of shallow water depths on initial dilution levels of heated water dischar... more In this study, effects of shallow water depths on initial dilution levels of heated water discharge from thermal effluent outfalls concerning water surface boundary effects using an inclined circular port were investigated. Receiving water environment was selected as stagnant and uniform characteristics. The inclination angle of discharge port was θ = 60°. Normalized port depths, H/dF, which was obtained from water depth (H) over port diameter (d) multiplied by densimetric Froude number (F) of jet defined as dF, were calculated for experimental setups. H/dF values were 3.871, 1.545, 1.160, 0.774, and 0.388 from deep to shallower depths, respectively. Rhodamine B was used as tracer of experiments. Normalized forms of impingement point horizontal distance values, x i /dF, and vertical distance values, y i /dF were decreased according to decreased water depths, H/dF. According to obtained results of this study, jet impingements occurred in the upper boundary of the receiving water body and they got closer to the nozzle when H/dF values decreased. In addition, the decreasing H/dF values caused a decrease in dilutions of horizontal distances for both complete jet centerlines (especially impact points compared to experimental) and VP estimates of free jet conditions. According to this study, VP dilution estimations were found very close to experimental impingement point dilutions no matter how VP software originally designed for only free jet conditions. This study suggests VP UM3 model can calculate realistic and conservative jet centerline dilutions at the impingement point in very limited depths in the range of normalized water depth ratio H/dF between 0.388 and 1.545.
ABSTRACT The purpose of the study described in this paper was to compare the removal of the heavy... more ABSTRACT The purpose of the study described in this paper was to compare the removal of the heavy metals zinc, nickel, and copper from synthetic wastewater by using nanoparticles of CuFe2O4 and NiFe2O4. The nanoparticles of nickel and copper ferrite (CuFe2O4 and NiFe2O4) were produced by the PEG assisted hydrothermal method. The structural and morphological characterizations were determined using XRD, FT-IR, and SEM. These nanoparticles were dispersed into synthetic wastewater contaminated with zinc, nickel, and copper. Once they had bound to the heavy metals, they were removed from the water solution using a strong magnet. The metal concentrations of the filtered samples were determined by using atomic absorption spectrophotometry (AAS). Then the heavy metal removal efficiencies and adsorption capacities of the nanoparticles (CuFe2O4 and NiFe2O4) were calculated. The removal efficiencies of Cu(II), Ni(II) and Zn(II) by using CuFe2O4 nanoparticles was calculated as 83.50%, 98.85%, and 99.80%, respectively. The removal efficiencies of Cu(II), Ni(II), and Zn(II) by using NiFe2O4 nanoparticles were calculated as 92.55%, 36.56%, and 99.91%, respectively. The measurements were repeated several times with the same sample and almost the same results were obtained each time.
15 Lake Van (eastern Turkey) earthquake (M w = 5.6) was retrieved using the method of Kikuchi & K... more 15 Lake Van (eastern Turkey) earthquake (M w = 5.6) was retrieved using the method of Kikuchi & Kanamori for source inversion of complex body waveforms. The event has been reported by USGS as a deep (67 km) subcrustal earthquake resulting from a rupture on a normal fault beneath the Bitlis Suture zone where continental collision is in action between the Arabian and Eurasian plates. However, our source model based on the analysis of complex body-waveforms suggests that the earthquake is a shallow crustal event comprised of two subevents on a predominantly reverse fault at depths of 12.5 and 15 km with a time interval of about 18 s. The seismic moment of the second subevent (M o = 1.6 × 10 17 Nm; strike = 76 • , dip = 55 • and rake = 120 •) is larger than the first subevent (M o = 1.0 × 10 17 Nm; strike = 87 • , dip = 62 • and rake = 110 •). Visual inspection of the strong ground motion records and waveform inversion analysis of the near-field records from four broad-band stations confirm the occurrence of the two subevents at shallow depths. We examined whether or not the observed complex waveforms of the main shock can be modelled in terms of a single point source embedded at an intermediate depth, and the result turned out to be further evidence for the multiple rupture. The plausibility of the focal depths and mechanisms of the two subevents was also examined by retrieving the source parameters of 14 aftershocks from near-field waveform data. Most of the aftershocks were relocated at depths around 15 km, which agrees with the shallow main shock. In addition, the analysis of near-field waveform data indicates subcrustal earthquake activity neither in the source region of the Lake Van earthquake nor in the Turkey-Iran border region. In the Turkey-Iran border region, an event on 1999 February 19 was reported to have taken place at a depth of 66 km (USGS) and 77 km (ISC), which also conflicts with our focal depth (18 km) determined through CMT inversion analysis of the broad-band records at the station GNI.
Bulletin of Environmental Contamination and Toxicology, 2013
The purpose of this study was to investigate the biodegradability of propylene glycol in anaerobi... more The purpose of this study was to investigate the biodegradability of propylene glycol in anaerobic conditions by using methanogenic culture. A master reactor was set up to develop a culture that would be acclimated to propylene glycol. After reaching steady-state, culture was transferred to serum bottles. Three reactors with same initial conditions were run for consistency. Propylene glycol was completely biodegradable under anaerobic methanogenic conditions. Semi-continuous reactors operated at a temperature of 35°C had consistently achieved a propylene glycol removal of higher than 95 % based on chemical oxygen demand (COD). It was found that in semi-continuous reactors, anaerobic treatment of propylene glycol at concentrations higher than 1,500 mg COD m(-3) day(-1) was not convenient due to instable effluent COD.
Madencilik endüstrisi modern toplumun gelişmesinde rol oynayan en önemli endüstriyel faaliyetleri... more Madencilik endüstrisi modern toplumun gelişmesinde rol oynayan en önemli endüstriyel faaliyetlerinden biri olmakla birlikte dünyanın en büyük atık üreten endüstrisidir. Gelişen teknoloji ve endüstriyel faaliyetlerin ihtiyacı olan hammaddelerin madencilik faaliyetleri ile doğal kaynaklardan elde edilmesi, biyolojik çeşitliliğin yok edilmesine ve çevre kirliliği sorunlarına neden olabilmektedir. Madencilik faaliyetlerinden vazgeçilmesi mümkün olmadığına göre, madenlerin çıkartılmasında kamu yararının yanında doğal kaynakların korunması ve çevre kirliliği oluşturmaması konusunda da daha duyarlı olunmalı ve uygun bertaraf yöntemleri için çeşitli mühendislik tekniklerinin uygulanması hedeflenmelidir. Madencilik faaliyetleri sonucu oluşan atıklardan olan çamur genel olarak arazilerde (atık barajlarında veya atık döküm sahalarında) depolanarak bertaraf edilmektedir. Bu depolama alanlarında ise asit maden drenajı (sülfit oksidasyonundan dolayı), geoteknik stabilite ve diğer bazı sebeplerden dolayı çevresel sorunlar meydana gelebilmektedir. Yerüstü atık barajları depolama alanlarında oluşan olumsuz nedenlerden dolayı maden atığı çamurların sucul alıcı ortamlarda bertarafı, özellikle sabit indirgeme koşulları altında ve sülfit minerallerinin jeokimyasal olarak istikrarlı olduğu derin deniz altlarında bertarafı bir seçenek olarak görülebilir. Bu çalışmada, maden atıklarının ve maden cevheri zenginleştirme atıklarından olan sulu çamurun (maden atık çamurunun) genel bertaraf yöntemleri, özellikle denizaltına deşarj ve denizaltında depolama yöntemi incelenmiştir. Bu yöntemin olası olumlu/olumsuz çevresel etkileri tartışılmıştır. Türkiye'de bulunan maden atığı çamuru derin denizaltı depolama (Karadeniz için) tesisi ve bu deşarjın (yöntemin) etkilerini belirlemek için yapılan deneysel çalışmalar değerlendirilmiştir. Bu kapsamda yapılan deneysel çalışmalar değerlendirildiğinde, derin deniz deşarjı tesisiyle Karadeniz'e deşarj edilen maden atık çamurlarının denizin tabanına doğru hareket eden bir atık olduğu (negatif yüzerliliğe sahip veya batan atık), anoksik bölgeden oksijenli bölgeye yükselemediği belirlenmiştir.
Polyacrylic acid diallyl dimethyl ammonium chloride (AAC-Dadmac) hydrogel was used as adsorbent f... more Polyacrylic acid diallyl dimethyl ammonium chloride (AAC-Dadmac) hydrogel was used as adsorbent for the removal of heavy metals (Cu(II), Ni(II), Zn(II) and total Cr) from electroplating wastewater. The effects of hydrogel dosage, contact time and shaking speed on heavy metal removal from electroplating wastewater were studied in a batch system. The equilibrium adsorption isotherm of heavy metals on the AAC-Dadmac hydrogel was studied using Langmuir and Freundlich isotherm models. The adsorption equilibrium data fitted well to the Langmuir isotherm model. The maximum adsorption capacities, q m (mg/g), of the AAC-Dadmac hydrogel for Cu(II), Ni(II), Zn(II) and total Cr were 2.336, 0.960, 5.319, and 4.608 mg/g, respectively. Kinetics of adsorption was found to follow the pseudo-second-order rate equation. The results showed that the AAC-Dadmac hydrogel can be used as an alternative adsorbent for the removal of heavy metal ions from electroplating wastewater.
In this study, effects of shallow water depths on initial dilution levels of heated water dischar... more In this study, effects of shallow water depths on initial dilution levels of heated water discharge from thermal effluent outfalls concerning water surface boundary effects using an inclined circular port were investigated. Receiving water environment was selected as stagnant and uniform characteristics. The inclination angle of discharge port was θ = 60°. Normalized port depths, H/dF, which was obtained from water depth (H) over port diameter (d) multiplied by densimetric Froude number (F) of jet defined as dF, were calculated for experimental setups. H/dF values were 3.871, 1.545, 1.160, 0.774, and 0.388 from deep to shallower depths, respectively. Rhodamine B was used as tracer of experiments. Normalized forms of impingement point horizontal distance values, x i /dF, and vertical distance values, y i /dF were decreased according to decreased water depths, H/dF. According to obtained results of this study, jet impingements occurred in the upper boundary of the receiving water body and they got closer to the nozzle when H/dF values decreased. In addition, the decreasing H/dF values caused a decrease in dilutions of horizontal distances for both complete jet centerlines (especially impact points compared to experimental) and VP estimates of free jet conditions. According to this study, VP dilution estimations were found very close to experimental impingement point dilutions no matter how VP software originally designed for only free jet conditions. This study suggests VP UM3 model can calculate realistic and conservative jet centerline dilutions at the impingement point in very limited depths in the range of normalized water depth ratio H/dF between 0.388 and 1.545.
ABSTRACT The purpose of the study described in this paper was to compare the removal of the heavy... more ABSTRACT The purpose of the study described in this paper was to compare the removal of the heavy metals zinc, nickel, and copper from synthetic wastewater by using nanoparticles of CuFe2O4 and NiFe2O4. The nanoparticles of nickel and copper ferrite (CuFe2O4 and NiFe2O4) were produced by the PEG assisted hydrothermal method. The structural and morphological characterizations were determined using XRD, FT-IR, and SEM. These nanoparticles were dispersed into synthetic wastewater contaminated with zinc, nickel, and copper. Once they had bound to the heavy metals, they were removed from the water solution using a strong magnet. The metal concentrations of the filtered samples were determined by using atomic absorption spectrophotometry (AAS). Then the heavy metal removal efficiencies and adsorption capacities of the nanoparticles (CuFe2O4 and NiFe2O4) were calculated. The removal efficiencies of Cu(II), Ni(II) and Zn(II) by using CuFe2O4 nanoparticles was calculated as 83.50%, 98.85%, and 99.80%, respectively. The removal efficiencies of Cu(II), Ni(II), and Zn(II) by using NiFe2O4 nanoparticles were calculated as 92.55%, 36.56%, and 99.91%, respectively. The measurements were repeated several times with the same sample and almost the same results were obtained each time.
15 Lake Van (eastern Turkey) earthquake (M w = 5.6) was retrieved using the method of Kikuchi & K... more 15 Lake Van (eastern Turkey) earthquake (M w = 5.6) was retrieved using the method of Kikuchi & Kanamori for source inversion of complex body waveforms. The event has been reported by USGS as a deep (67 km) subcrustal earthquake resulting from a rupture on a normal fault beneath the Bitlis Suture zone where continental collision is in action between the Arabian and Eurasian plates. However, our source model based on the analysis of complex body-waveforms suggests that the earthquake is a shallow crustal event comprised of two subevents on a predominantly reverse fault at depths of 12.5 and 15 km with a time interval of about 18 s. The seismic moment of the second subevent (M o = 1.6 × 10 17 Nm; strike = 76 • , dip = 55 • and rake = 120 •) is larger than the first subevent (M o = 1.0 × 10 17 Nm; strike = 87 • , dip = 62 • and rake = 110 •). Visual inspection of the strong ground motion records and waveform inversion analysis of the near-field records from four broad-band stations confirm the occurrence of the two subevents at shallow depths. We examined whether or not the observed complex waveforms of the main shock can be modelled in terms of a single point source embedded at an intermediate depth, and the result turned out to be further evidence for the multiple rupture. The plausibility of the focal depths and mechanisms of the two subevents was also examined by retrieving the source parameters of 14 aftershocks from near-field waveform data. Most of the aftershocks were relocated at depths around 15 km, which agrees with the shallow main shock. In addition, the analysis of near-field waveform data indicates subcrustal earthquake activity neither in the source region of the Lake Van earthquake nor in the Turkey-Iran border region. In the Turkey-Iran border region, an event on 1999 February 19 was reported to have taken place at a depth of 66 km (USGS) and 77 km (ISC), which also conflicts with our focal depth (18 km) determined through CMT inversion analysis of the broad-band records at the station GNI.
Bulletin of Environmental Contamination and Toxicology, 2013
The purpose of this study was to investigate the biodegradability of propylene glycol in anaerobi... more The purpose of this study was to investigate the biodegradability of propylene glycol in anaerobic conditions by using methanogenic culture. A master reactor was set up to develop a culture that would be acclimated to propylene glycol. After reaching steady-state, culture was transferred to serum bottles. Three reactors with same initial conditions were run for consistency. Propylene glycol was completely biodegradable under anaerobic methanogenic conditions. Semi-continuous reactors operated at a temperature of 35°C had consistently achieved a propylene glycol removal of higher than 95 % based on chemical oxygen demand (COD). It was found that in semi-continuous reactors, anaerobic treatment of propylene glycol at concentrations higher than 1,500 mg COD m(-3) day(-1) was not convenient due to instable effluent COD.
Uploads
Papers by Naim Sezgin