Mehmet Cakmakcı

Yıldız Technical University · Department of Environmental Engineering

The objective of this study is to improve the filtration efficiency of commercially available PES ultrafiltration membranes, with a specific focus on removing NOMs and preventing membrane fouling. The modification of ultrafiltration membranes was accomplished by utilizing chitosan-multi walled carbon nanotube (CS/MWCNT-OH) and employing both dip an...

The mixed wastewater generated by anodic oxidation coating facilities contains high levels of various contaminants, including iron, aluminum, conductivity, chemical oxygen demand (COD), and sulfate. In this study, the effectiveness of the membrane distillation (MD) process using polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) memb...

Bioflocculants can be used for cost-effective harvesting of microalgae biomass on an industrial scale. This study investigates the flocculation-based harvesting approach to recovering Chlorella vulgaris microalgae biomass using chitosan biopolymer. Response surface methodology (RSM) was used to design the experiments and optimize the critical opera...

Oxytetracycline (OTC) is a tetracycline group antibiotic with high environmental pollution potential and is resistant to conventional treatment processes. This study provides an environmentally friendly and efficient OTC treatment by ultraviolet (UV)-based advanced oxidation processes. UV irradiation was used for the activation of hydrogen peroxide...

The acidic anodic oxidation plating facility has high-strength wastewater which contains pollutants such as sulfate, chemical oxygen demand (COD), conductivity, aluminum, and iron. This study investigated the treatability of acidic wastewater provided by an anodized plating facility using chemical precipitation and membrane distillation (MD) techni...

Silt density index (SDI) and Modified fouling index (MFI) are tests to measure and assess the fouling potential of pressure driven membranes such as reverse osmosis (RO) and nanofiltration (NF), which are widely used in water treatment applications. The process efficiency and the useful membrane life of such systems are mainly affected by the fouli...

Vanadium is a naturally occurring metal that can be found in the earth's crust at concentrations of 100 mg/kg. Vanadium are annually entered the environment from natural sources almost 65.000 tonnes and from anthropogenic sources almost 200.000 tonnes. In this study, vanadium removal was investigated by precipitating iron(III) chloride (FeCl3) from...

A lab-scale reverse electrodialysis module was constructed to highlight the optimal feed solutions concentration, the flow rate and their importance in improving the power density in reverse electrodialysis. The results showed that the increase of the feed solutions flow rate is beneficial by augmenting the power output, but too high flow rate harm...

The reverse electrodialysis (RED) process fed with natural solutions was operated for six days and resulted to power densities for the combination ultrafiltration (UF) effluent-seawater, membrane bioreactor (MBR) effluent-seawater, advanced biological treatment (ABT) effluents-seawater around 0.52, 0.50 and 0.48 W.m−2, respectively, while the synth...

The present study investigated the reverse electrodialysis (RED) energy generation potential of treated wastewaters from Ataköy and Ambarlı wastewater treatment plant (WWTP) when discharged at the Marmara Sea. The good quality of the WWTP effluents and their suitable conductivity (around 1 mS.cm⁻¹) resulted in a power density around 0.5 W.m⁻² when...

Fossil fuel is scanty and negatively affects the earth by inducing climate change. As a result, alternative and renewable energy (RE) sources are being investigated to replace fossil fuel. Wind and solar energy are leaders in the RE market, but huge and accessible other energy sources such as salinity gradient power (SGP) exist and need to be colle...

Landfill leachate is high-strength wastewater containing harmful pollutants and very rich in ammonia (NH3), an undesired element in wastewaters. NH3 is used as a liquid fertilizer in agriculture and as a reactant in many other fields. The present study investigated the reclamation of NH3 during the treatment of middle-age landfill leachate by direc...

Ammonium (NH4 +) is an undesired compound in wastewater, but when isolated it is a useful product. The recovery of ammonium from contaminated sources such as landfill leachates can be beneficial as it could be used as a liquid fertilizer in the agriculture and as a reactant in many other fields. The present study investigated the recovery of NH4 +...

Rinsing wastewater from dyeing and bleaching processes in a cotton dyeing facility has been separately characterized to evaluate the suitable treatment processes and reuse options. Alternative treatment processes were proposed based on molecular weight distribution (MWD), ultraviolet absorbance of 254 nm (UV254) and specific ultraviolet absorbance...

Compost leachate contains high concentrations of organic matter, sulphate and ammonia which requires combined treatment systems. In case of the use of membrane containing combined systems, the effect of pretreatment on molecular weight distribution (MWD) is important in terms of appropriate membrane selection. In this study the leachate from Istanb...

Membrane distillation (MD) is a well-known process for the quality of the treatment effluents. However, the quality of the permeate solution depends on many parameters including the feed solution pollutants natures and concentrations. In the present study, the permeate quality and the transmembrane flux of a direct contact membrane distillation (DC...

Membrane distillation (MD) is a process of point for purification of highly polluted waters. As a membrane process, the management of the generated concentrate that is almost 30% of the initial feed solution is one of the major issue in MD. In the present study, the evaporation of the concentrate from a DCMD performed using a hydrophobic polytetraf...

The purpose of this study was to investigate membrane fouling caused by microalgal cells in submerged membrane systems consisting of polymeric and ceramic microfiltration membranes. In this study, one polymeric (flat-sheet, pore size: 0.2 μm) and two ceramic (flat-sheet, pore size: 0.2 μm and cylindrical, pore size: 1 μm) membranes were used. Physi...

The removal of some pollutants in the Sakarya River was investigated in this study. Sakarya River located in Turkey flows from the northeast of Afyonkarahisar City to the Black Sea. Nineteen different micropollutants including trihalomethanes (THMs), haloacetic acids (HAAs), endocrine disrupting compound (EDC) and pharmaceuticals personal care prod...

The performances of the hydrophobic polytetrafluoroethylene (PTFE) membranes purchased from Hangzhou Anow (HA) Microfiltration Co. Ltd., Solar Spring (SS) GmbH and Membrane Solution (MS) have been investigated in a direct contact membrane distillation process (DCMD) for the treatment of landfill leachate. The contact angles of the membranes, the tr...

Landfill leachate is a high strength wastewater with a high content of pollutants and very rich in ammonium (NH4+). NH4+ is undesired in wastewater, but it is a useful product. The present study investigated the recovery of NH4+ during the treatment of landfill leachate by direct contact membrane distillation (DCMD). The treatment was performed wit...

Landfill leachate is a high-strength wastewater with high concentration of harmful pollutants and is produced in almost all countries with high variation in constituents. In this study, a modified direct contact membrane distillation (DCMD) has been used to investigate the treatability of raw and pretreated landfill leachate. Two different hydropho...

In this study, hydrophilic and fouling-resistant polysulfone (PS) membranes were fabricated using the phase inversion method to reduce membrane fouling caused by microalgal culture. The Pluronic F-127 polymer, which is used as a hydrophilic co-polymer, was added to the membranes to improve the membrane properties. Characteristic specifications of t...

Fossil fuel reserves which supplying a major portion of energy needs, are depleting rapidly, and its environmental damages increases day by day. Therefore, like all developed and developing countries, our country have focused on the use of renewable energy sources. Within this scope in the our country, it was aimed gain of renewable energy sources...

Bu calismada, ticari ve laboratuvar ortaminda uretilen farkli ozelliklere sahip polimerik membranlarla evsel atiksularin aritilabilirligi arastirilmistir. Calisma dikey akisli duz plaka membran modulunde 4 adet ticari membran (UP005, UP020, US100 ve NF270) ve 5 adet farkli oranlarda hazirlanmis kitosan (Ct) ve Fe 3 O 4 katkili poliakrilonitril (PAN...

The present study investigated the treatability of raw and biologically pretreated municipal wastewater (MWW) by direct contact membrane distillation (DCMD). The treatment was performed at three various feed temperatures, 40, 50 and 60 0C and at constant 10 oC cooling water, with two hydrophobic membranes made of polytetrafluoroethylene (PTFE) and...

The aim of the study was to investigate oxidative precipitation of As(III) with ozone and sodium hypochlorite in Fe(II) containing water. As guideline value was achieved with both ozone and hypochlorite for 100 µg/l of initial As(III) concentration. High As removal efficiencies were achieved by dosing 2.5 and 5 times the stoichiometric amounts of h...

The purpose of this study was to investigate the efficient harvesting of microalgal biomass through crossflow membrane filtration. The microalgal biomass harvesting experiments were performed using one microfiltration membrane (pore size: 0.2 µm, made from polyvinylidene fluoride) and three ultrafiltration membranes (molecular weight cut-off: 150,...

The main objective of this study was to determine whether methane potential of waste could be estimated more easily by a limited number of waste characterization variables. 36 samples were collected from 12 locations and 3 waste depths in order to represent almost all waste ages at the landfill. Actual remaining methane potential of all samples was...

Main objective of this study was to develop a statistical model for easier and faster Biochemical Methane Potential (BMP) prediction of landfilled municipal solid waste by analyzing waste composition of excavated samples from 12 sampling points and three waste depths representing different landfilling ages of closed and active sections of a sanitar...

In this study, electricity production from old age landfill leachate was investigated using dual chambered microbial fuel cell with Ti-TiO2 electrodes. The effect of organic loading rate on microbial fuel cell performance was examined by changing the hydraulic retention time and leachate chemical oxygen demand (COD) concentration. Microbial diversi...

In this study, the treatability of metal-plating waste water by modified direct contact membrane distillation (DCMD) at different temperature differences (∆T = 30°C, 40°C, 50°C, and 55°C was investigated. Two different hydrophobic membranes made of poly(tetrafluoroethylene) (PTFE) and poly(vinylidene fluoride) (PVDF) having different pore sizes (0....

The main objective of this study was to investigate the differences between the main pollutants in young and intermediate age landfill leachate in terms of molecular weight distribution (MWD). Parameters of chemical oxygen demand (COD), five day - biochemical oxygen demand (BOD5), ultraviolet-visible spectrophotometry (UV-VIS spectrum), total kjehl...

This study investigated the treatability and changes in molecular weight distributions (MWD) of membrane concentrate. Nanofiltration (NF) concentrate from textile wastewater was subjected sole anaerobic treatment (R1) and pre-ozonation (R2) plus anaerobic treatment. BOD5, COD and TOC, color, sulphate and specific ultraviolet absorbtion at 254 nm (S...

In this study, the treatability of arsenic (As) contaminated water by direct contact membrane distillation (DCMD) at different delta temperatures (ΔT) 30, 40 and 50°C has been investigated. Two different pore sizes (0.22 μm and 0.45 μm) of hydrophobic membranes made of polyvinylidene fluoride (PVDF) were used. The membrane pore sizes, the operating...

The present study investigated the influence of ferric iron (Fe (III)) and organic matter (OM) on arsenite (As (III)) rejection from a synthetic contaminated water by direct contact membrane distillation (DCMD). Two different pore sizes (0.22 μm and 0.45 μm) of hydrophobic membranes made of Polytetrafluoroethylene (PTFE) were used at different feed...

This study was focused on anaerobic treatment of textile wastewater. In this research, treatability of concentrate from nanofiltration of textile wastewater. Results indicated that membrane concentrate could be effectively treated with bacterial treatment. Moreover it can be said that both fermantors were approximately the same in terms of removal...

In this study, the treatability of metal-plating waste water by modified direct contact membrane distillation (DCMD) at different temperature differences (ΔT = 30◦C, 40◦C, 50◦C, and 55◦C was investigated. Two different hydrophobic membranes made of poly(tetrafluoroethylene) (PTFE) and poly(vinylidene fluoride) (PVDF) having different pore sizes (0....

The removal of arsenic was investigated by four types of thin-film polyamide nanofiltration (NF) (NF270, NF90) and reverse osmosis (RO) (XLE, BW30) membranes in a flat-sheet module. The influence of membrane types, pressure, pH, and pre-oxidation step on the removal of arsenic (As(III)) was investigated. Initial As(III) concentration was 100 μg/l f...

The main drawback of membrane processes is biological membrane fouling which, in turn, leads to the membrane having an increased amount of transmembrane pressure and energy consumption. The fouling of microfiltration (MF) and ultrafiltration (UF) membranes caused by microalgal cells was investigated in this study. An MF membrane with a pore size of...

Composting has been attracting increased interest in the field of organic waste management. During composting, high-strength leachate is produced with a considerable amount of organic and inorganic pollutants. Lab-scale experiments were performed for the removal of chemical oxygen demand (COD) and chloride from compost leachate using a combined mem...

Composting has been attracting increased interest in the field of organic waste management. During composting, high-strength leachate is produced with a considerable amount of organic and inorganic pollutants. Lab-scale experiments were performed for the removal of chemical oxygen demand (COD) and chloride from compost leachate using a combined mem...

Considerable research has been conducted on the treatment of dairy wastewater by anaerobic granular reactors. Upflow anaerobic sludge blanket (UASB) reactors, anaerobic sequencing batch reactors (ASBR) and static granular bed reactors (SGBR) are the conventional granular reactor types most commonly applied in dairy wastewater treatment. Hybrid syst...

Electricity production from brewery wastewater using dual‐chamber microbial fuel cells (MFCs) with a tin‐coated copper mesh in the anode was investigated by changing the hydraulic retention time (HRT). The MFCs were fed with wastewater samples from the inlet (inflow, MFC‐1) and outlet (outflow, MFC‐2) of an anaerobic digester of a brewery wastewate...

Many different chemicals are used in the textile industry, with its effluent being a major pollution source if not treated properly. High-strength textile wastewater requires an environmentally friendly, cost-effective and highly efficient treatment before being discharged into the environment. The goal of this study is to determine the appropriate...

Hydrogen (H2) is one of the most promising alternative fuel sources for satisfying future energy demand, and fermentative hydrogen production is advantageous over other processes. In recent decades, considerable research has been conducted on H2 production from carbohydrate-rich materials since it is a cost-effective approach and has the ability to...

A concentrate stream is generated by the application of nanofiltration (NF) membranes in wastewater reuse. Due to the high concentrations of pollutants, disposal of NF concentrates is an important problem. In this study, ozonation and anaerobic treatment processes were performed to treat cotton dyeing textile mill wastewater NF concentrate. After o...

This study focused on using beer brewery wastewater (BBW) to evaluate membrane concentrate disposal and production of electricity in microbial fuel cells. In the membrane treatment of BBW, the membrane permeate concentration was 570 ± 30 mg/L corresponding to a chemical oxygen demand (COD) removal efficiency of 75 ± 5%, and the flux values changed...

The objective of this study was to investigate powdered activated carbon (PAC) contribution to natural organic matter (NOM) removal by a submerged MF and UF hybrid systems. It was found that filtration of surface waters by a bare MF and UF membranes removed negligible TOC; by contrast, significant amounts of TOC were removed when daily added PAC pa...

In this study, the two-chambered microbial fuel cell (MFC) was continuously long-term operated a young landfill leachate in order to evaluate the impact of cation exchange membrane (CEM) fouling on MFC performance. During the operation, the voltage output decreased sharply to almost zero and the voltage output was recovered completely after replace...

Arsenic removal from drinking water using low-pressure membranes together with chemical oxidation and adsorption on ferric iron coagulates was deeply investigated. Hypochlorite or ozone was used to oxidize arsenite (100 or 1000 μg/L) and ferrous iron (0.5–20 mg/L) simultaneously. As(III) or As(V) rejection by ultrafiltration was negligible. Althoug...

Intercountry and intercontinental transport increasingly continues. In this regard, maritime transport has a major play role due to being cheaper and more reliable. Globalization and technological advances has been a major driving force for goods and people move at a much faster rate and to reach far more distances locations as soon as possible. No...

In recent years, many efforts on electrode materials and microbial fuel cell (MFC) configurations have been made for improving MFC performance. Surface areas of electrodes are one of the important factors for increasing power. High surface areas of electrodes can significantly increase of power density [1-3]. For this reason, tubular electrodes are...

Microbial fuel cell (MFC) is a generally considered to be a sustainable new technology converting to electricity the chemical energy in organic compounds. MFC consists of two components with anode and cathode chambers. In the anodic chamber, electrons and protons are generated due to the anaerobic oxidation of organics (1, 2). New studies about a n...

Changes in temperature, pH, moisture, C/N ratio, and bacterial community were monitored in Istanbul full-scale composting plant. C/N ratio steadily decreased during composting and final mature compost products had a C/N ratio of less than 20. During the composting process, temperature was mostly above 55 °C and decreased to mesophilic conditions in...

In this study, Molecular weight (MW) distributions of a full-scale landfill leachate treatment plant consisting of membrane bioreactor (MBR) and nanofiltration (NF) membrane were investigated. The leachate was sampled from the equalization tank, and effluents of MBR and NF membrane in the landfill leachate treatment plant. Parameters of COD, TOC, T...

This study was focused on anaerobic treatment of textile wastewater. In this research, treatability of concentrate from nanofiltration of textile wastewater. Results indicated that membrane concentrate could be effectively treated with bacterial treatment. Moreover it can be said that both fermantors were approximately the same in terms of removal...

The effect of meteorological factors on the composition and the energy recovery of the landfill gas (LFG) were evaluated in this study. Landfill gas data consisting of methane, carbon dioxide, and oxygen content as well as LFG temperature were collected from April 2009 to March 2010 along with meteorological data. The data set were, first, used to...

The main product of the conversion process of organic wastes to a useful organic fertilizer, known as compost, has gained an increasing interest in management of organic wastes recently. One of the main problems arising in the composting facilities is the high organic loaded leachate. In this study, a treatability experiment for composting leachate...

This study aims at evaluating the performance of a two-chambered continuously fed microbial fuel cell with new Ti-TiO(2) electrodes for bioelectricity generation from young landfill leachate at varying strength of wastewater (1-50 COD g/L) and hydraulic retention time (HRT, 0.25-2 days). The COD removal efficiency in the MFC increased with time and...

This study presents biotreatment of textile wastewaters using electrocoagulation and ozone processes. Ozonation process gave better results than electrocoagulation process. For electrocoagulation, optimum working conditions were found as follows: pH, 6.5; electrode type, iron electrode; current density, 20 mA/cm2; and reaction time, 15 min. Under t...

A literature survey was conducted to appraise the recent applications of artifical intelligence (AI)-based modeling studies in the environmental engineering field. A number of studies on artificial neural networks (ANN), fuzzy logic and adaptive neuro-fuzzy systems (ANFIS) were reviewed and important aspects of these models were highlighted. The re...

In Turkey, particularly in Istanbul, almost all of the surface and underground water sources contain ferrous iron [Fe(II)] at high concentration levels, which generate serious problems in use of water for industrial processes and at drinking water treatment plants. Ferric iron [Fe(III)] on the other hand precipitates as Fe(OH)3 and blocks the filte...

Effluent iron concentration is an important water quality criterion used for the assessment of the performance of rapid sand filters, in addition to other criteria. This study deals with the prediction of effluent iron concentrations by adaptive neuro-fuzzy (ANFIS) model with input parameters including filter hydraulic loading rate, influent iron c...

Arsenic occurs naturally in the ground and surface water and is not desired in the drinking water due to carcinogenic effect on human body. The common types of arsenic are arsenate (As V) and arsenite (As III). Although arsenate removal has been achieved by membranes, adsorption, ion exchange and coagulation, arsenite removal is diffi cult to decre...

Breakthrough and terminal head loss are the main parameters that determine the performance of rapid sand filters. Carman‐Kozeny and Ergun equations can be applied to estimate head loss, but can only be applied to clean filter beds. Elaborated models are needed to predict head loss in dirty filters. In this study, a neuro‐fuzzy modeling approach was...