Prospective life cycle assessment (LCA) studies are widely used for evaluating emerging resource recovery systems. Simulations, engineering-based process calculations and stoichiometric methods are frequently used methods to generate life cycle inventory (LCI) in prospective LCAs. The engineering-based upscaling calculation is an efficient method for LCI generation requiring fewer resources than simulations. This study aims to test an engineering-based upscaling method for LCI generation and adapt it to biochemical resource recovery processes. The method's validity for biochemical resource recovery processes was tested using data for biogas generation by anaerobic digestion in laboratory, pilot, and full scales, and using a combination of lab-scale data and kinetic equations. Biogas generation was chosen for two reasons: (1) there are several emerging technologies based on anaerobic digestion with products other than biogas, and (2) data is available for different scales. The results showed, a substantial difference between the methane production amount in actual and conceptual plants, is an important cause of the variation in impact category results. Different estimations of fugitive emissions have an important impact on the global warming potential results. Combination of lab-scale data and kinetic equations approximates best with the actual plant for the abiotic depletion, eutrophication, freshwater aquatic ecotoxicity, global warming and photochemical ozone creation potentials. The results are sensitive to biogas generation amount in several categories.

Water is among the essential inputs of many industrial production processes. Substantial amounts of water with varying qualities is of importance in running quite a number of industrial sectors. The water quality requirements necessitate the application of different water purification systems. This study concentrates on comparing the environmental impacts of reverse osmosis and an ion exchange system that treat the water supplied from a well to a quality suitable for boiler water makeup. Life cycle assessment methodology is adopted for this evaluation. Purification system with the ion exchanger requires 18.6% less energy in comparison with the reverse osmosis system. However, substantially higher environmental impacts are obtained for the ion exchanger system when compared with the treatment scheme of reverse osmosis. Hence, the reverse osmosis system should be favored. Changing the source of energy from the grid mix to wind power is observed to further reduce abiotic depletion potential (fossil), human toxicity potential, acidification potential, eutrophication potential, and terrestric ecotoxicity potential for the reverse osmosis system.

This study concentrates on environmental impacts of PCB manufacturing. The objective is to examine the effect of Cu recycling rate, transportation, energy sources and end-of-life (EoL) on global warming potential (GWP), marine aquatic ecotoxicity potential (MAEP), terrestric ecotoxicity potential (TETP), freshwater aquatic ecotoxicity potential (FAETP), human toxicity potential (HTP), ozone layer depletion (ODP), photochemical ozone creation potential (POCP), eutrophication potential (EP), acidification potential (AP) and abiotic depletion potential (ADP fossil, ADP elements) potentials. Increasing Cu recycling rate from 30% to 47%, reduce the impacts by 10 to 103%. The most significant reduction is for HTP. Transportation elevates AP and POCP by 29%, ADP fossil by 23% and GWP by 21%. Obtaining energy from renewable sources causes 56, 40 and 39% reductions in HTP, ADP fossil and GWP, namely. Apart from GWP where PCB manufacturing and EoL has equal impacts, for the other categories PCB manufacturing has more than 75% contribution.

The transition from wastewater treatment plants to wastewater resource recovery facilities has led to research into and development of various new processes. The production from wastewater of volatile fatty acids (VFAs), an intermediate product of anaerobic digestion, is one of these processes. The purpose of this study is to evaluate the environmental sustainability of VFA production from dairy wastewater, which is still in the laboratory research phase, and to investigate the discrepancies between lab-scale and conceptual full-scale life cycle assessment (LCA) results. In laboratory-scale LCA, electricity consumption for mixing and heating is the major contributor to all impact categories. The material usage and disposal of these materials also contribute significantly to the environmental impacts. Full-scale LCA results show that heating of the reactor and addition of NaOH during the operation stage are the main contributors. Scenario analysis is conducted for heating device efficiency and operating temperature. The recommendations are to use alternative chemicals to NaOH or to co-treat dairy wastewater with alkaline wastewater, using a heating device with a high efficiency, and to try experiments at lower temperatures. There are discrepancies between the LCA results based on laboratory data and upscale data, meaning that there is a further need for investigation of upscaling for LCA purposes.

The aim of this study has been to investigate the environmental impacts of an innovative food waste management system and compare it with landfilling as a conventional waste management option. The investigated system is still in the laboratory research and development phase. Therefore, inventory data of the laboratory scale food waste management system was collected and then up-scaled for life cycle assessment purposes. The proposed system consists of a hygenization reactor followed by a fermenter and then a centrifuge. The system converts food waste into volatile fatty acid-rich supernatant. Functional unit is management of 1 ton food waste. The results indicate that the proposed system is a better option than landfilling in terms of all impact categories. The produced VFA-rich supernatant is supposed to be used as a replacement for methanol in the denitrification process. In one of the impact categories (ozone depletion potential) the avoided burdens are higher than the burdens and the system provides net gain (-2.82E-07 kg R11 eq.). Majority of the environmental burdens in the proposed system are due to heat consumption for hygenization. Including sludge disposal in the investigated system boundary increases the environmental burdens but the burdens are still lower compared to landfilling option.

The linear pattern of production-consumption-disposal of cities around the world will continue to increase the emission of pollutants and stocks of waste, as well as to impact on the irreversible deterioration of non-renewable stocks of raw materials. A transition towards a circular pattern proposed by the concept of 'Circular Cities' is gaining momentum. As part of this urban transition, the emergent use of Nature-based Solutions (NBS) intends to shift public opinion and utilize technology to mitigate the urban environmental impact. In this paper, an analysis of the current research and practical investments for implementing NBS under the umbrella of Circular Cities is conducted. A combined appraisal of the latest literature and a survey of ongoing and completed National-European research and development projects provides an overview of the current enabling tools, methodologies, and initiatives for public engagement. It also identifies and describes the links between facilitators and barriers with respect to existing policies and regulations, public awareness and engagement, and scientific and technological instruments. The paper concludes introducing the most promising methods, physical and digital technologies that may lead the way to Sustainable Circular Cities. The results of this research provide useful insight for citizens, scientists, practitioners, investors, policy makers, and strategists to channel efforts on switching from a linear to a circular thinking for the future of cities.

The objective of this study is to examine the environmental impacts arising from the construction phase of a large conventional water treatment plant located in Istanbul by adopting a life cycle assessment methodology. The facility has a maximum flow rate of 400,000 m(3)/d and serves a population of about 2,600,000. A conventional treatment technology composed of rock and fine screens, aeration, coagulation-flocculation units, clarifiers, filters, chlorination, and sludge handling units, is used in the plant. The functional unit is 1,000 kg (1 m(3)) treated water. The investigated environmental impact categories are: global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), abiotic depletion potential fossil (ADP fossil), freshwater aquatic ecotoxicity potential (FAETP), human toxicity potential ( HTP), marine aquatic ecotoxicity potential (MAETP), and terrestrial ecotoxicity potential (TETP). The main contributors to GWP, AP, EP, and HTP are concrete and structural steel. FAETP and TETP are mostly arising due to the polyvinyl chloride pipelines and membranes, and the concrete used. The main shares in MAETP are concrete, aluminum, and structural steel. Transportation does not have a significant contribution to environmental impacts.

The objective of this study is to appraise the environmental burdens of a cataphoresis process, most widely used surface coating operation in automotive sector. An industry having an annual production of around 6,100 trucks and busses is investigated by adopting life cycle assessment methodology. This study is a pioneering one performed with the actual data obtained from a Turkish automotive factory. The impact categories evaluated are climate change, acidification potential, particulate matter and respiratory inorganics, photochemical ozone formation, ecotoxicity freshwater potential, terrestrial eutrophication potential, freshwater eutrophication potential, marine eutrophication potential, human toxicity midpoint cancer effects, ozone depletion potential, and resource depletion (water). The total energy consumption of the cataphoresis process is approximately 12.5 kWh/m(2). Electrodeposition coating and the following ultrafiltration water rinse baths are the main sources of the environmental impacts. The contribution of transportation has insignificant effects on environmental impacts for all categories. Furthermore, energy consumption has substantial influence on almost all of the environmental impact categories. The results related to various energy scenarios conducted with wind, photovoltaic and hard coal instead of Turkish grid electricity indicate the usage of wind energy lowers all impacts.