Katı atık yönetiminin geliştirilmesinde malzeme akış analizi: Ankara örneği

The progress of recent civilisation and the associated growth in population worldwide has contributed considerably to the increase in the quantity of waste produced. The ever-increasing consumption of resources has resulted in high amounts of solid waste from domestic activities, which can pose significant threats to the environment and human health. Waste management and recycling activities have a complex and multifaceted mechanism that requires comprehensive and integrated approaches. In this study, the current status of municipal solid waste management in Ankara was identified and waste streams were investigated by using Materials Flow Analysis (Stan 2 software). It was aimed to analyse material flows by visualising the waste management system of Ankara. This study resulted that approximately 1.6 million tonnes of solid waste is collected per year (4500 tonnes per day) in the province. Almost 470 thousand tonnes of it is being used for methane production and more than 400 thousand tonnes of compost is being produced each year. The result of the model also points out that 286 thousand tonnes get accumulated in landfills each year. This reveals the possible requirement for a capacity investment of Mamak Landfill Area, which is already on the agenda of city authorities.Sürekli gelişim ve buna bağlı olarak dünya çapında nüfusla ilişkili büyüme, üretilen atık miktarındaki artışa önemli ölçüde katkıda bulunmuştur. Giderek fazlalaşan kaynak tüketimi, üretilen evsel katı atık miktarının artmasına neden olmuş, bu da çevre ve insan sağlığı için önemli bir tehdit oluşturmaya başlamıştır. Atık yönetimi ve geri dönüşüm faaliyetleri, kapsamlı ve entegre yaklaşımlar gerektiren karmaşık ve çok yönlü bir mekanizmaya sahiptir. Bu çalışmada, Ankara ilindeki evsel katı atık yönetiminin mevcut durumu belirlenip, katı atık akımları, Malzeme Akış Analizi (Stan 2 yazılımı) kullanılarak araştırılmıştır. Bu çalışmanın amacı, Ankara ilinin atık yönetiminin görsel olarak ortaya çıkarılıp atık akımlarının analiz edilmesidir. Bu çalışma göstermiştir ki, Ankara’da her yıl yaklaşık 1,6 milyon ton katı atık (günde 4500 ton) toplanmaktadır. Toplanan bu atıkların yılda yaklaşık 470 bin tonluk kısmı metan üretimi için, 400 bin tondan fazlası ise kompost üretimi için kullanılmaktadır. Ayrıca, model sonucuna göre düzenli depolama alanlarında her yıl 286 bin ton atık biriktiği tespit edilmiştir. Bu durum, şehir yetkililerinin de gündeminde olan Mamak Atık Depolama Sahası için kapasite arttırımı ihtiyacına işaret etmektedir

Characterisation of aluminium industrial wastewater and investigation of recovery alternatives

Aluminium industry is one of the largest sectors and wastewater generated from this industry could cause crucial environmental problems due to its high heavy metal concentration and conductivity. Therefore, this study aims to determine the characterisation of the wastewater discharged from the two aluminium facilities by considering water recovery potential. While Facility-A produces stainless steel kitchenware, such as pots and pans, In Facility-B, anodised coating takes place from secondary aluminium and wastewater is generated from the units where anodised coating baths and control processes are carried out. For the analyses, the wastewater composite samples from different sections, such as washing, sand-blasting and dyeing in Facility-A were taken in 2 and 24 hours. In Facility-B, three 2-hour composite influent water samples and an effluent sample from chemical wastewater treatment were taken to determine conductivity, pH, chemical oxygen demand (COD), total suspended solids (TSS), etc. As a result of the analyses made, a high value of TSS was detected at all sampling points in Facility-A. It was also seen that the conductivity after demineralisation process in Facility-A was below 30. In Facility-B, it was determined that while the pH obtained from two influent samples was below the discharge limits and showed acidic characteristics, one sample was very basic with a pH value of 12.19 and exceeds the upper limit of discharge. All influent samples in Facility-B show high TSS content in comparison with discharge limits specified in the regulation

Characterisation study of solid wastes: A case of districts in Tekirdağ

In this study, solid waste characterisation of high-income, middle-income, low-income regions and market areas in Tekirdağ Metropolitan Municipality was carried out in winter and summer, 2016. As a result, the amount of organic wastes (kitchen wastes, park and green wastes) and packaging waste (paper, cardboard, bulky cardboard, plastics, glass, metals and bulky metals) in Tekirdağ were determined as 41.02% and 32.4% respectively, by waste sampling. When waste characterisation was analysed based on the districts, it was seen that paper and plastic waste is mostly produced from the Çorlu district. The reason for this could be the high level of welfare of the citizens living in Çorlu and the high number of working people compared to other districts due to the high density of industrial facilities. It was also seen that the ash percentage of waste is high in the districts of Hayrabolu, Şarköy, Muratlı, Marmaraereğlisi, Malkara and Saray, which are the districts not covered by natural gas distribution grid. Waste samples were characterised in the Tubitak Energy Institute Laboratory to determine the moisture content, calorific value and glow loss. The results showed that there is a high moisture and organic matter in the wastes, which makes the incineration method not suitable for the treatment of solid wastes in Tekirdağ. The results of this study highlighted that there is a potential for introducing recycling schemes especially in high income regions in Tekirdağ. To initiate such programmes, collected municipal waste could be separated in two streams in place; organics and co-mingled dry-recyclables

EXPLORING THE EFFECT OF COVID-19 ON MUNICIPAL WASTE GENERATION WITH SYSTEM DYNAMICS MODELLING

This study examines the dynamic change in population and municipal waste generation during the COVID-19 pandemic. A stockflow infection modelling was used to link population dynamics with disease transmission parameters (such as probability to catch COVID-19 and population interactions) to estimate municipal waste generation in the province of Tekirdag, Turkey. Three different scenarios (Scenario 1: severe conditions with possible mutation of coronavirus, Scenario 2: moderate conditions with the continuation of the current case and Scenario 3: mild conditions with intensified vaccination) were produced and simulation results were analysed. The results show that it is expected to have a peak with 230 000 people with severe symptoms in Scenario 1. It is also expected to have 1 person/week to pass away due to inadequate health infrastructure if the annual healthcare capacity improvement rate in the province remains at its current rate (1%). The results indicate that the amount of dry recyclables increases over time in the three scenarios. However, in Scenario 3, a total of 450 000 - 780 000 tonnes of dry recyclables are expected to be produced at the end of 3 years. This high amount of waste is likely to cause dynamism in the recycling activities of the province. As far as it is concerned that 750 000 - 1 000 000 tonnes of residual waste (including used masks) are expected to be produced in Scenario 3, capacity improvement for the only landfill site of the province should be made urgently or an alternative solid waste disposal facility should be put into use to meet this need

Comparison of Conventional and Ultrasonic-Assisted Adsorption Processes by Using H3PO4 Activated Cypress Tree Cone for Methylene Blue Removal (vol 44, pg 269, 2022)

[Abstract Not Available

Comparison of Conventional and Ultrasonic-Assisted Adsorption Processes by Using H3PO4 Activated Cypress Tree Cone for Methylene Blue Removal

Recycling agricultural waste, such as corn cobs, tree cones or grape stalks, contributes to converting waste into a new resource by encouraging the development of the circular economy. In this study, colour removal efficiency of H3PO4 activated cypress tree cone (H3PO4-CTC) from Methylene Blue (MB) (C16H18N3SCl) was investigated by using conventional and ultrasonic-assisted adsorption processes. The properties of the prepared H3PO4-CTC adsorbent were obtained by SEM-EDX and FTIR analysis, and the optimum pH and adsorbent dose effect on MB adsorption was determined. Kinetic and isotherm models were presented for conventional and ultrasonic-assisted adsorption processes under optimum conditions. The removal of MB was found favourable at conventional and ultrasonic-assisted adsorption processes. Comparing the Freundlich isotherm, the Langmuir isotherm was also found to fit the experimental data more. According to the Langmuir isotherm, qmax values were obtained as 3.87 and 4.50 mg/g, respectively, by conventional and ultrasonic-assisted adsorption processes. It was also determined that MB removal was over 90% in the first two uses of H3PO4-CTC. In the study, it was observed that H3PO4 activated cypress tree cone could be used as a low-cost adsorbent in MB adsorption, and it was also seen that MB adsorption could be increased with the ultrasonic adsorption process compared to the conventional adsorption process

Decolorization potential of reactive dyes by using galvanising industry's waste (aluminum hydroxide sludge) depending on dye chromophore

The galvanising industry's wastewater treatment facilities generate waste metal hydroxide. These sludges have the potential to be used to remove textile dyes from effluents. In this study, three reactive dyes, which are frequently used in cellulosic textile materials' dyeing, Remazol Turquoise Blue G 133% (CI RB21), Remazol Red 3B (CI RR23), and Remazol Red 3BS 133% (CI RR239) were used to investigate the color removal efficiency of aluminum hydroxide sludge (AHS) depending on dye chromophore. Adsorption studies were conducted under varying conditions of pH, initial dye concentrations, and AHS doses. The characteristics of the AHS were examined by SEM (EDX and DX-Mapping), BET, XRD, and FTIR. The maximum dye removal was achieved at pH 3 for CI RB21, and at pH 5 for CI RR239 and CI RR23. Over 90% of dye removal was obtained for CI RR239 and CI RB21, when the adsorbent dosages were 8 g/l and 5 g/l, respectively. For CI RR23, the highest color removal percentage was only 72.7%, when the dosage of adsorbent was 10 g/l. It was also determined that at 500 mg/l initial CI RB21 dye concentration, the removal percentage of CI RB21 reached 95%, while the maximum removal percentages (95% for CI RR239 and 68.3% for CI RR23) were achieved at the 200 mg/l and 100 mg/l initial dye concentrations for CI RR239 and CI RR23, respectively. In the study, it was observed that the number of sulfo groups affecting the ionic charge of dye molecules and molecular weights of the dyes have a significant effect on the dye removal efficiency

Synthesis of ZnCl2 Activated Raising Powder of Cotton Fabrics for Acid and Basic Dye Adsorption: A Way to Reuse Cellulosic Wastes for Sustainable Production

In this study, Cl Basic Blue 9 (BB9) and Cl Acid Blue 193 (AB193) dyes were used to investigate the color removal efficiency of the carbon-based adsorbent material, ZnCl2-RP, which was obtained by activating the raising powder. The raising powder is a waste material that is generated in considerable amounts from the textile industry. The characterization of ZnCl2-RP was conducted by SEM-EDX, FTIR, XRD and BET analyses. As a result of this study, it was determined that ZnCl2-RP contains 4.15% of Zn. While no significant effect of pH on the adsorption of BB9 dye was observed in the experiments, the highest dye removal efficiency was achieved at pH 3. It was seen that Langmuir Isotherm for both dyes was more suitable than the Freundlich Isotherm and the q(max) values of the BB9 and AB193 dyes were 44.8 mg/g and 37.6 mg/g, respectively. Removal kinetics of both dyes were found in accordance with the pseudo-second order kinetics, and k(2) values for 50 mg/L dye concentration were 45.62 g/mg min and 5.31 g/mg min for BB9 and AB193, respectively. It is concluded that the raising powder generated in the textile industry can be used as a low-cost adsorbent for basic and acid dyes

Improvement of anode/HTL interface properties using self-assembled monolayer in organic electronic devices

Fabrication and characterization of highly effcient organic light-emitting diode with surface modification of indium tin oxide anodes by using self-assembled monolayer technique have been studied. Four different self-assembled molecules, K-28 ruthenium complex, octadecylamine hydrochloride, octadecyltrichlorosilane and mercaptohexdecanoic acid are used to modify ITO surface to improve the interface properties. Space charge limited currents measurements have been used to evaluate carrier mobility under steady state current. The results show that the surface properties such as the stability of ITO anode layer have significant effects on charge injection in organic light-emitting diode devices.TUBITAK under grant No. TBAG-108T71

Experimental and computational investigation of graphene/SAMs/n-Si Schottky diodes

We have investigated the effect of two different self-assembled monolayers (SAMs) on electrical characteristics of bilayer graphene (BLG)/n-Si Schottky diodes. Novel 4″bis(diphenylamino)-1, 1′:3″-terphenyl-5′ carboxylic acids (TPA) and 4,4-di-9H-carbazol-9-yl-1,1′:3′1′-terphenyl-5′ carboxylic acid (CAR) aromatic SAMs have been used to modify n-Si surfaces. Cyclic voltammetry (CV) and Kelvin probe force microscopy (KPFM) results have been evaluated to verify the modification of n-Si surface. The current–voltage (I–V) characteristics of bare and SAMs modified devices show rectification behaviour verifying a Schottky junction at the interface. The ideality factors (n) from ln(I)–V dependences were determined as 2.13, 1.96 and 2.07 for BLG/n-Si, BLG/TPA/n-Si and BLG/CAR/n-Si Schottky diodes, respectively. In addition, Schottky barrier height (SBH) and series resistance (R s ) of SAMs modified diodes were decreased compared to bare diode due to the formation of a compatible interface between graphene and Si as well as π–π interaction between aromatic SAMs and graphene. The CAR-based device exhibits better diode characteristic compared to the TPA-based device. Computational simulations show that the BLG/CAR system exhibits smaller energy-level-differences than the BLG/TPA, which supports the experimental findings of a lower Schottky barrier and series resistance in BLG/CAR diode.The Scientific and Technical Research Council of Turkey (112T946