Prof. Dr. Nilgün Cılız danışmanlığındaki tezler
11 tez · Boğaziçi University
Comparative life cycle assessment of plastic (PET), glass, and aluminum cans for soft drink packaging in accordance with the transition to decarbonisation and pollution prevention principles
Packaging materials have numerous applications in our daily lives and in industry. One of them is soft drink packaging products. Both in Turkey (locally) and the EU, packaging-related regulations, directives, and policies have been updated in accordance with circular economy and the EU Green Deal principles. Although LCA is associated with the cradle-to-grave approach, when considering this concept under the circular economy approach, the cradle-to-cradle approach can also be adopted. Therefore, Sustainable Consumption and Production (SDG 12) is a point that needs to be related to Life Cycle Assessment (LCA). The primary objective of this study is to assess the environmental outcomes associated with decarbonization, reuse, recycling, and recycled content targets by conducting a Life Cycle Assessment (LCA) across various scenarios for soft drink packaging of PET, glass, and aluminum. During scenario development, relatable actions were taken together with the EU Green Deal, circular economy, and Paris Agreement targets. Initially, only for the pre-consumer stage, 2020 was set as the baseline scenario, i.e., for the production of the selected materials, less renewable energy and no recycled content were considered. With the increasing share of renewable electricity, 2035 and 2053 were targeted to improve both the pre-consumer stage by applying electrified systems and recycled content, and the post-consumer stage by supporting reuse and recycling. In the context of the selected impact categories, the thesis concluded that for the pre-consumer stage of each product, the use of recycled content, electrified processes and renewable electricity have favorable aspects under proper conditions. Attention must be paid to the necessary efficiency and redesign points in renewable electricity generation and electrification process. In the post-consumer stage, the reuse process (especially for glass) can be promoted in terms of primary resource savings and energy efficiency by improving water consumption in the washing (also applied in recycling) processes. While the reuse stage for PET sounds more environmentally friendly but needs to be considered in the context of health concerns and product durability during consumption, but as well as the aluminum, recycling for PET must be supported compared to their remanufacturing.
Resource and environmental profile evaluation of personal care and cosmetic products with life cycle assessment methodology
Resource and energy depletion have been limiting for many industries, including the personal care and cosmetic products (PCCPs) sector. Moreover, intense use of chemical ingredients has fastened emerging problems occurring in aquatic environments at the end of life of these chemicals. As they have an immense ecological footprint, their fate should be tracked for elimination of the adverse environmental impacts. The PCCPs sector has reached a large trade capacity due to accelerating demands of consumers. As the participation of companies/policymakers to the green initiatives affects the behavior intention of consumers, the sales rate of ecolabelled products have ascended. Correspondingly, manufacturers are required to choose ingredients considering potential improvements towards product formulations, to lessen the environmental impacts of their product chain, to promote their products as environmentally friendly, and to fulfil the consumers' expectations. Under the guidance of ecolabel standards, a selected group of PCCPs (liquid & bar soaps, shampoo, hair conditioner, body cleaning products) was analyzed with LCA methodology. Two products providing the same service in each product category were compared to determine environmental hotspots in their product chain. Although characterization results varied depending on the life cycle stage by composition, consumption, and end-of-life stages, Global Warming Potential (GWP) was the highest impact category for all the selected products. The highest contribution to GWP originated from wastewater treatment (WWT) and transportation processes in hand wash products while in shower products energy use in production & consumption, and the WWT process had the highest impact; 90.3 % and 7.4 %, respectively.
Environmental sustainability for selected packaging wastes
Rapid production and consumption have led to increase in the waste generation in the past several decades. According to the Eurostat (2018) 19% of total municipal solid waste is comprised of packaging waste. To alleviate the environmental impacts associated with packaging waste in both production and disposal phases, recycling is a key solution. The aim of this study is to evaluate selected plastic and glass beverage packaging wastes in Turkey according to the national recycling targets using a Life Cycle Assessment (LCA) methodology and provide science-based recommendations for development of roadmap for achieving sustainable consumption and production goals. For this purpose, the current years (2017 and 2018) and the future (2025) national and EU recycling targets were assessed by LCA on an annual basis. The data for both production and recycling processes were obtained from packaging factories and recycling facilities. The energy processes used in the study were calculated according to the primary energy sources of the relevant year. With this study, the contribution of recycling to the environmental impacts of glass and PET packaging during the life cycle was analyzed.
Development of electricity production from lignite and hard coal LCA processes for future national database of Turkey
The reliability of life cycle assessment (LCA) studies is determined by the quality of the inventory data used in the analysis and the degree to which the processes reflect the true production conditions of the country. The goal of this study is to develop country-average LCA processes for electricity production from lignite and hard coal of Turkey. Air emissions for 15 lignite and 8 hard coal power plants operating in Turkey were estimated based on coal combustion and emission control technologies and the properties of coal utilized at the plants using the emission factors of the United States Environmental Protection Agency (US EPA) WebFIRE database. The calculated emission values were then used to developed the country average electricity production processes from lignite and hard coal using Ecoinvent template datasets. The environmental impacts of the newly developed and the original Ecoinvent processes were compared for consistency using LCA methodology. The air emission calculations for CO2, CO, N2O, NOx and SOx have yielded values that are close to the values in Ecoinvent datasets, with most accurate results obtained for CO and SOx emissions in lignite and CO2 and NOx emissions in hard coal processes. LCA comparison has revealed the environmental impacts of the newly developed processes to be comparable with their Ecoinvent counterparts, where difference in total normalized environmental impacts are less than 2% for lignite and 21% for hard coal processes. In overall, the obtained results demonstrate the adequacy of the approach utilized in the study for developing the LCA energy processes.
Environmental sustainability analysis of renewable energy generation with photovoltaic solar panels in Turkey
ENVIRONMENTAL SUSTAINABILITY ANALYSIS OF RENEWABLE ENERGY GENERATION WITH PHOTOVOLTAIC SOLAR PANELS IN TURKEY Life Cycle Assessment is a method that scrutinizes in detail the toxic environmental effects of products and services over their entire life span. The aim of this study is to reveal the environmental effects of solar panels, which are accepted as the cleanest method of obtaining energy, throughout their life cycle and to present a more sustainable solar energy generation roadmap. For this reason, multi-Si PV solar panel type, which is the most widely used type and dominates the world market, has been studied. Environmental impact categories were assessed using GaBi 9.5 Software, EcoInvent Database and CML Assessment Methodology. While evaluating the life cycle of the multi-Si PV panel, metallurgical silicon smelting, solar grade multi-Si purification, wafer slicing, ingot casting, cell processing, panel assembly, transportations and recycling stages were studied. In addition, three different recycling scenarios, which diverge according to delamination methods, were also examined in terms of their environmental effects. Thus, a framework has been put forward on how the toxic effects of solar panels at the end of their life can be minimized. In this research, both real sector data and literature data were used. The multisilicon production process, which consists of the stages of metallurgical silicon smelting and solar grade multi-Si purification, and module assembly stage emerged as the two processes that cause the most environmental impact. In recycling scenarios, the FRELP2 process, which is a combination of thermal and chemical delamination processes, provided the best results in terms of environmental impact.
Evaluating environmental burdens and resource consumption in the olive oil industry by using LCA methodology
Türkiye is one of the major worldwide olive oil producers; thus, it is substantial to examine and evaluate the environmental impacts of its production. In this study, virgin olive oil production in Türkiye is extensively evaluated concerning its environmental impacts utilizing the life cycle assessment methodology with cradle-to-gate approach. Additionally, the environmental performance of two and three-phase extraction technologies was compared, the importance of fertilization in raw material extraction stage was assessed, the environmental impacts of valorization of waste were discussed, and the study was related to Türkiye's 2030 Climate Change and 2053 Net Zero Targets. Additionally, the impact of the use of chemicals in olive orchards is comprehensively analyzed, referencing The EU Green Deal Farm to Fork Strategy .These analyses are intended to emphasize the potential contribution of sustainable agriculture to virgin olive oil production and its environmental performance. The outcomes of the study are examined: global warming potential, abiotic depletion , eutrophication potential, and marine aquatic ecotoxicity potential impact categories. The analysis showed that the agricultural activities had the highest environmental impacts, and increasing the share of renewable energy sources in electricity generation improved the environmental performance of producing 1 kg of unpacked virgin olive oil. Furthermore, the two-phase extraction method showed more environmentally favorable results, and waste valorization processes proved crucial. Additionally, it becomes evident that Türkiye's VOO production holds an important position in terms of environmental impacts. The study emphasize the necessity of adopting cleaner energy resources, improved agricultural practices, and optimizing industrial processes.
The potentials and limitations of utilizing animal manure for biogas production in rural agricultural households: A comprehensive analysis of Ethiopia and Türkiye
With the growing threat of climate change and global warming along with the exponential exploitation of resources, the need for adaptation of renewable and cleaner energy technologies especially in emerging and developing economies has been inevitable. This thesis provides a comprehensive analysis of the potentials and limitations associated with the utilization of animal manure for biogas production in rural agricultural households, with a specific focus on Ethiopia and Türkiye. The thesis aims to identify the key factors that influence the adoption of biogas technology in these countries and provide insights into the socio-economic and environmental benefits and challenges associated with the use of animal manure for energy generation. The thesis employs a mixed-methods approach that combines a systematic literature review with primary data collected through surveys and interviews with farmers, policymakers, and other stakeholders. The results reveal that the utilization of animal manure for biogas production has significant potential for rural agricultural households in both Ethiopia and Türkiye, as it can provide an efficient, reliable, and affordable source of energy while also reducing greenhouse gas emissions. However, the thesis also highlights several limitations and challenges that need to be addressed to promote the uptake of biogas technology in these countries. These include technical, financial, and policy-related barriers, as well as social and cultural factors that influence the acceptance and use of biogas systems.
Evaluation of the environmental impacts of the selected household appliances via life cycle assessment approach
With industrialization, products which make human life more comfortable have become widespread and household appliances having adverse environmental impacts on earth's system through their lifecycle are one of those product groups. On behalf of minimizing the adverse impact of human living on the earth system, the current environmental impact of these products should be measured and analyzed. Since environmental impacts cannot be minimized unless it is measured and analyzed regarding their hot spots. The objective measurement of product groups' environmental impacts is figured out through life cycle assessment (LCA) from cradle to grave within the scope of CML 2001 method by using GaBi 8 software in this study for the use phase having the highest environmental impact in some of the impact categories of dishwashers, washing machines, and refrigerators due to their high electricity consumption. The impact categories with the largest environmental impact include CC, ADP-Fossil fuel, FAETP, HTP, and MAETP, according to the normalization result. The goal of this study is to compare the impact of possible scenarios for circular economy approaches including cleaner electricity mix of Türkiye in 2035, product durability, customer choices, and behavior, and to lessen their environmental burden. As a result of this study, the most environmentally friendly scenarios are the combination of Türkiye's 2035 electricity mix, 20 % fewer washing cycles and 20 % more energy-efficient (S8), and renewing the appliances with 20 % more energy-efficient ones (S5) for Türkiye to achieve its net zero emission target instead of extending lifespan up to 2053.
Potential environmental impacts of plastic packaging of consumer goods in Mediterranean Region
Synthetic plastics produced from non-renewable resources are widely utilized through its useful practices. Packaging is also an industry that highly consumes plastics around 44%, when other plastic industries are considered. The main polymer types, polyolefins, polystyrene, polyethylene-terephthalate, which are broadly used in consumer goods packaging involve single use plastics and cause damage on the environment including marine ecosystem. As impacts on the marine environment has also gained an extensive potential through Mediterranean Action Plan, main objective of this study is determined to assess potential environmental impacts of three plastic packaging materials in Turkey, Italy and Spain which represent nearly 14% of plastic pollution and 100 ton/day of plastic waste disposal in the region. Five environmental impact categories of climate change, acidification, resource depletion, ozone depletion, and photochemical ozone formation were studied to obtain results of packaging materials according to ReCiPe 2016 v1.1 and CML2001–Jan.2016 methodologies with GaBi 9.1.2 software. This study has shown that polypropylene material has had the highest environmental impact results in CML and ReCiPe methodologies due to fossil dependency. Moreover, scenarios with higher renewable energy share in their electricity grid, have received normalization results that have lower environmental impact. Packaging reduction targets set by European Commission were also lowered the environmental impact scores in the implemented scenarios. Climate change and resource depletion impact categories were obtained highest normalization scores among the five environmental impact categories. Also, scenarios with end-of-life options which includes higher recycling shares and lower incineration shares have taken lower environmental impact scores.
Adopting sustainable waste management practices in selected household wastes with green energy approach via life cycle assessment
Over decades, humankind has become more responsible for depletion of Natural Resources (NR) and disturbing the ecological balance of Earth's systems due to rising population and excess amount of industrialization practices. The demand for NR has increased, which leads to call for action on Sustainable Consumption and Production (SCP) patterns globally. In this manner, sustainability and green growth practices in daily short-term and long-term consumer goods as well as sustainable end-of-life practices should be promoted. In this study, food, paper, packaging; and household e-waste (electrical and electronic equipment) are analyzed with the Life Cycle Assessment (LCA) methodology. Sustainable Waste Management (WM) is targeted; mainly focusing on efficiency in recycling rates as proposed in European Union Waste Framework Directive (EU WFD), aiming transition to greener economy. Environmental impacts arising from recycling these wastes are analyzed by conducting LCA studies for a typical family's daily household activities. Different recycling rates of waste products are presented in the light of Turkey's National Energy Plan, and Turkey's Decarbonization Roadmap within the EU Circular Economy Action Plan perspective. The proposed strategies are integrated into the study by comparing the country's electricity generation profile in 2020 with the proposed electricity generation shares of 2030, 2035 and 2050 scenarios as well as EU's recycling rate targets. The results which also consider increased public awareness on recycling clearly revealed that, by developing sustainable public behaviour, in addition to increased recycling efficiency, the increased share of using renewable energy in the recycling equipment significantly reduces the studied environmental impacts.
Life cycle assessment for valorization of orange and apple juice residues
Healthy diet trends increased the demand for natural and nutrient beverages, including fruit juices. In the ever-growing fruit juice market, orange and apple juice are the most popular flavors. Nearly half of the cultivated fruits are processed into juice, creating a great amount of residue. The current waste management techniques for these residues are landfilling or composting. Instead, they can be valorized to produce value-added products within the circular economy model. As the resources are finite, transitioning to a circular economy model is crucial for a sustainable future. Novel technologies have been emerging to support a circular and biobased economy to utilize agricultural waste. In this study, life cycle assessment (LCA) methodology was applied for orange juice residues to produce d-limonene and pectin; and for apple juice residues to produce succinic acid and xylitol. D-limonene was extracted by cold-pressing and solvent-free microwave extraction and pectin was extracted by acid hydrolysis. Waste apple pomace was used to produce succinic acid and xylitol by fermentation. The valorization routes were compared with landfilling, showing all of them performed better environmentally except succinic acid. 3 future scenarios were created based on the decarbonization of electricity and agriculture for climate goals. Results showed that the environmental impacts were caused by intensive electricity use in production and agricultural production, so valorization routes would perform better in future scenarios with decarbonization in electricity and agriculture.