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Bioconcrete is widely believed to be environmentally beneficial over conventional concrete. However, the process of bioconcrete production involves several steps, such as waste recovery and treatment, that potentially present significant environmental impacts. Existing life-cycle assessments of bioconcrete are limited in the inventory and impact analysis; therefore, they do not consider all the steps involved in concrete production and the corresponding impacts. The purpose of this study is to extensively study the cradle-to-gate environmental impacts of all the production stages of two most common bioconcrete types (i.e. sludge-based bioconcrete and cement kiln dust-rice husk ash (CKD-RHA) bioconcrete) as opposed to conventional concrete.

A cradle-to-gate life-cycle assessment process model is implemented to systematically analyze and quantify the resources consumed and the environmental impacts caused by the production of bioconcrete as opposed to the production of conventional concrete. The impacts analyzed in this assessment include global warming potential, ozone depletion potential, eutrophication, acidification, ecotoxicity, smog, fossil fuel use, human toxicity, particulate air and water consumption.

The results indicated that sludge-based bioconcrete had higher levels of global warming potential, eutrophication, acidification, ecotoxicity, fossil fuel use, human toxicity and particulate air than both conventional concrete and CKD-RHA bioconcrete.

The contribution of this study to the state of knowledge is that it sheds light on the hidden impacts of bioconcrete. The contribution to the state of practice is that the results of this study inform the bioconcrete production designers about the production processes with the highest impact.

Sustainable agriculture implies the ability of agro‐ecosystems to remain productive in the long‐term. It is not easy to point out unambiguously whether or not current production systems meet this sustainability demand. A priori thinking would suggest that organic crops are environmentally favourable, but may ignore the effect of reduced productivity, which shifts the potential impact to other parts of the food provision system. The purpose of this paper is to assess the ecological sustainability of conventional and organic leek production by means of life cycle assessment (LCA).

A cradle‐to‐farm gate LCA is applied, based on real farm data from two research centres. For a consistent comparison, two functional units (FU) were defined: 1ha and 1 kg of leek production.

Assessed on an area basis, organic farming shows a more favourable environmental profile. These overall benefits are strongly reduced when the lower yields are taken into account. Related to organic farming it is therefore important that solutions are found to substantially increase the yields without increasing the environmental burden. Related to conventional farming, important potential for environmental improvements are in optimising the farm nutrient flows, reducing pesticide use and increasing its self‐supporting capacity.

The research is a cradle‐to‐farm gate LCA, future research can be expanded to comprise all phases from cradle‐to‐grave to get an idea of the total sustainability of our present food consumption patterns. The research is also limited to the case of leek production. Future research can apply the methodology to other crops.

To date, there is still lack of clear evidence of the added value of organic farming compared to conventional farming on environmental basis. Few studies have compared organic and conventional food production by means of LCA. This paper addresses these issues.

The purpose of this study is to compare the environmental impacts of two additive manufacturing machines to a traditional computer numerical control (CNC) milling machine to determine which method is the most sustainable.

A life-cycle assessment (LCA) was performed, comparing a Haas VF0 CNC mill to two methods of additive manufacturing: a Dimension 1200BST FDM and an Objet Connex 350 “inkjet”/“polyjet”. The LCA’s functional unit was the manufacturing of two specific parts in acrylonitrile butadiene styrene (ABS) plastic or similar polymer, as required by the machines. The scope was cradle to grave, including embodied impacts, transportation, energy used during manufacturing, energy used while idling and in standby, material used in final parts, waste material generated, cutting fluid for CNC, and disposal. Several scenarios were considered, all scored using the ReCiPe Endpoint H and IMPACT 2002+ methodologies.

Results showed that the sustainability of additive manufacturing vs CNC machining depends primarily on the per cent utilization of each machine. Higher utilization both reduces idling energy use and amortizes the embodied impacts of each machine. For both three-dimensional (3D) printers, electricity use is always the dominant impact, but for CNC at maximum utilization, material waste became dominant, and cutting fluid was roughly on par with electricity use. At both high and low utilization, the fused deposition modeling (FDM) machine had the lowest ecological impacts per part. The inkjet machine sometimes performed better and sometimes worse than CNC, depending on idle time/energy and on process parameters.

The study only compared additive manufacturing in plastic, and did not include other additive manufacturing technologies, such as selective laser sintering or stereolithography. It also does not include post-processing that might bring the surface finish of FDM parts up to the quality of inkjet or CNC parts.

Designers and engineers seeking to minimize the environmental impacts of their prototypes should share high-utilization machines, and are advised to use FDM machines over CNC mills or polyjet machines if they provide sufficient quality of surface finish.

This is the first paper quantitatively comparing the environmental impacts of additive manufacturing with traditional machining. It also provides a more comprehensive measurement of environmental impacts than most studies of either milling or additive manufacturing alone – it includes not merely CO₂ emissions or waste but also acidification, eutrophication, human toxicity, ecotoxicity and other impact categories. Designers, engineers and job shop managers may use the results to guide sourcing or purchasing decisions related to rapid prototyping.

The UK′s Control of Industrial Major Accident Hazards (CIMAH) Regulations 1984 implement the European Communities “Seveso” Directive (82/501/EEC). Central to these regulations are requirements for manufacturers in control of qualifying activities which meet certain indicative criteria or involve specific dangerous substances in an industrial activity to provide evidence which identifies the major accident hazards from their activities and which shows that they have taken adequate steps to prevent such major accidents and to limit their consequences to people and the environment. Provides background to a presentation at “Disaster ′93” which will outline the environmental aspects of CIMAH with particular reference to the technical difficulties and current research work involved in the assessment of major accidents to the environment.

The purpose of this research is to establish that data on chemicals detected in the environment are urgently needed to comply with the future environment and chemicals policy in the European Union. The availability of data on chemicals can be evaluated by environmetrical and chemometrical methods.

The Hasse Diagram Technique (HDT) which originated in discrete mathematics is applied in this paper. It is a multi‐criteria evaluation method which can be used to measure information quality and is therefore also applicable for decision making. The study evaluated 15 environmental and chemical free internet databases with respect to the existence of data on chemicals in these resources. Two test‐sets were used first, 12 high production volume chemicals and, second 12 pharmaceuticals which are proven to enter the environment in considerable concentrations.

The evaluation indicates a rather disturbing situation in the data availability on existing chemicals, an especially bad result concerning the data availability on pharmaceuticals and hence an alarming signal concerning the chemicals policy of the EEC.

The information gap, especially for pharmaceuticals entering the environment, is demonstrated with a mathematically recognised method. The Hasse Diagram Technique can be applied to different questions in science when several objects are to be ranked by several criteria at the same time. Concerning the topic of the data availability on chemicals, the gaps are identified and should inspire future research to generate new and valuable data.

This study aims to introduce an approach to evaluate environmental impact of a piston-prop engine from the view point of life cycle assessment (LCA).

In the aviation industry, safety is an important issue. For reliable and safe flights, the maintenance of aerial vehicles and engines is mandatory. Additionally, regular and correct maintenance plays a key role in keeping efficiency at a high level. With this in mind, a LCA of a regular 50 hourly maintenance process of Cessna type training aircraft is conducted. During the assessment, the starting of the engine before maintenance, replacement of the oil filter, test procedure of the spark plugs, a compressor test, engine cleaning and engine starting following maintenance are taken into account.

At the end of the study, normalization and characterization values for the maintenance, electricity consumption during maintenance and used fuel are obtained.

Regarding the number of this type aircraft worldwide, the current study offers a valuable contribution to the literature. The authors also intend to introduce an approach which may be useful for the assessment of large body aircraft still in service.

The present paper is a pioneer for future applications of LCA methodology to piston-prop engines and training aircraft.

The aim of this study is to understand the environmental benefits and economic savings associated with adoption of circular economy in the construction sector. The research findings will support different stakeholders and decision makers to develop business models based on responsible consumption of resources and build sustainable business models.

The research uses mixed methodology wherein inventory for life cycle assessment and life cycle costing for environmental and economic impacts is based on primary data using on-site visits for qualitative and quantitative data.

Different types of land transportation infrastructures are compared for their environmental impacts. It is found that bridges have the highest environmental impacts as compared to tunnels, roads and railways. Further, the results affirm the environmental and economic benefits of adopting circular economy practices.

This is one of a kind research that compares the environmental and economic tradeoffs of adopting circular economy in different types of land transportation infrastructures.

Wastewater treatment plants (WWTPs) have long-time environmental impacts. The purpose of this paper is to assess the environmental footprint of two advanced wastewater treatment (WWT) technologies in a life cycle and sustainability perspective and identify the improvement alternatives.

In this study life cycle-based environmental assessment of two advanced WWT technologies (moving bed biofilm reactor (MBBR) and sequencing batch reactor (SBR)) has been carried out to compare different technological options. Life cycle impacts were computed using GaBi software employing the CML 2 (2010) methodology. Primary data were collected and analysed through surveys and on-site visits to WWTPs. The present study attempts to achieve significantly transparent results using life cycle assessment (LCA) in limited availability of data.

The results of both direct measurements in the studied wastewater systems and the LCA support the fact that advanced treatment has the best environmental performance. The results show that the operation phase contributes to nearly 99 per cent for the impacts of the plant. The study identified emissions associated with electricity production required to operate the WWTPs, chemical usage, emissions to water from treated effluent and heavy metal emissions from waste sludge applied to land are the major contributors for overall environmental impacts. SBR is found to be the best option for WWT as compared to MBBR in the urban context. In order to improve the overall environmental performance, the wastewater recovery, that is, reusable water should be improved. Further, sludge utilisation for energy recovery should be considered. The results of the study show that the avoided impacts of energy recovery can be even greater than direct impacts of greenhouse gas emissions from the wastewater system. Therefore, measures which combine reusing wastewater with energy generation should be preferred. The study highlights the major shortcoming, i.e., the lack of national life cycle inventories and databases in India limiting the wide application of LCA in the context of environmental decision making.

The results of this study express only the environmental impacts of the operation phase of WWT system and sludge management options. Therefore, it is recommended that further LCAs studies should be carried out to investigate construction and demolition phase and also there is need to reconsider the toxicological- and pathogen-related impact categories. The results obtained through this type of LCA studies can be used in the decision-making framework for selection of appropriate WWT technology by considering LCA results as one of the attributes.

The results of LCA modelling show that though the environmental impacts associated with advanced technologies are high, these technologies produce the good reusable quality of effluent. In areas where water is scarce, governments should promote reusing wastewater by providing additional treatment under safe conditions as much as possible with advanced WWT. The LCA model for WWT and management planning can be used for the environmental assessment of WWT technologies.

The current work provides a site-specific data on sustainable WWT and management. The study contributes to the development of the regional reference input data for LCA (inventory development) in the domain of wastewater management.

The life cycle assessment (LCA) guide of Heijungs et al. has been renewed to the latest methodological developments, aiming to make the ISO 14040 series on life cycle assessment operational. For this, a closer look was taken at intended applications in relation to required and practicable modelling options. Applications determine the required theoretical model, but the theoretical model required often comes into conflict with the available practical models and the needed operationality for decision support. To ease the tension between these requirements, simplifications need to be made in a guide on LCA. Two levels of sophistication have been worked out in the new guide documents: a detailed LCA with some options for extensions, and a simplified version.

This study aims to present the impact of using leaded avgas in piston-prop aircraft, in Turkey.

Increasing air traffic directly increases the total amount of consumed aviation fuels (kerosene or avgas). The number of aircraft and traffic that will increase soon will further increase fuel consumption. For this reason, aircraft power generation methods (long term) must be changed or the fuel must be improved (short term). The avgas used in piston-prop aircraft is known to contain lead and as a result, the production or consumption of avgas has adverse effects on human health, the ecosystem quality and resources.

The overall human health impact, ecosystem quality impact and resource impact in Turkey were determined to be 2.83 disability-adjusted life years, 1.21 × 10⁻⁰⁴ species.yr and $138, respectively. According to the results, although the normalized total effect of Turkey was calculated as 208.18 nkg, 43.89% of the total was observed in the Marmara region.

The originality is the use of real-time values for all calculations. For the purpose of showing the most impacted or damaged regions in Turkey via a life cycle analysis, a new definition, the normalized total effect in nkg, is defined in this study.