Life Cycle Impact Assessment of Recycled Aggregate Concrete, Geopolymer Concrete, and Recycled Aggregate-Based Geopolymer Concrete

This study presents a life cycle impact assessment of OPC concrete, recycled aggregate concrete, geopolymer concrete, and recycled aggregate-based geopolymer concrete by using the mid-point approach of the CML 2001 impact-assessment method. The life cycle impact assessment was carried out using OpenLCA software with nine different impact categories, such as global warming potential, acidification potential, eutrophication potential, ozone depletion potential, photochemical oxidant formation, human toxicity, marine aquatic ecotoxicity, and freshwater and terrestrial aquatic ecotoxicity potential. Subsequently, a contribution analysis was conducted for all nine impact categories. The analysis showed that using geopolymer concrete in place of OPC concrete can reduce global warming potential by up to 53.7%. Further, the use of geopolymer concrete represents the reduction of acidification potential and photochemical oxidant formation in the impact categories, along with climate change. However, the potential impacts of marine aquatic ecotoxicity, freshwater aquatic ecotoxicity, human toxicity, eutrophication potential, ozone depletion potential, and terrestrial aquatic ecotoxicity potential were increased using geopolymer concrete. The increase in these impacts was due to the presence of alkaline activators such as sodium hydroxide and sodium silicate. The use of recycled aggregates in both OPC concrete and geopolymer concrete reduces all the environmental impacts.

Life Cycle Assessment of Ethiopian Cement Manufacturing: A Potential Improvement on the Use of Fossil Fuel in Mugher Cement Factory

The use of imported fuel in the Ethiopian cement industry increased the cost of production and the environmental burden, necessitating intervention. The greenhouse gas (GHG) emission, energy usage intensity, and resource exploitation of Ethiopian cement production were evaluated using the life cycle impact assessment (LCA) tool, aiming to recommend improvements. The LCA study used cumulative energy demand (CED) and Intergovernmental Panel on Climate Change (IPCC) 2006 life cycle impact assessment (LCIA) methods. For the case study of Mugher cement factory (MCF), the results on energy use intensities showed 3.74, 3.67, and 2.64 GJ/ton of clinker, Ordinary Portland cement (OPC), Pozzolana Portland cement (PPC), respectively. The result revealed MCF's energy use intensity was within the global range of 3.32 to 5.11 GJ/ton of cement production using similar kiln technology. The results on the GHG emissions were 0.87, 0.84, and 0.59 tons of CO2-equivalent/ton of clinker, OPC, and PPC, respectively. Process emissions accounted for 60% of overall CO2 emissions, with energy-related emissions accounting for the remaining 40%. CO2 emissions of MCF are below the global limit of 0.9 tons/ton of clinker, where all energy sources are fossil fuels. However, it is higher than the 0.65 ton/ton of clinker from a moderate rotary kiln in China. MCF used 70% of its total energy sources from imported fossil fuels, and transportation of the imported fuel added 1.2% CO2 to total emissions. A suggested fossil fuel use improvement scenario for MCF, where coffee husk replaces 50% of the imported coal improved the energy intensity, GHG emissions, and total cost of coal in clinker production by 1.2%, 14%, 36%, respectively.

Life-cycle impact assessment methods for physical energy scarcity: considerations and suggestions

Purpose Most approaches for energy use assessment in life cycle assessment do not consider the scarcity of energy resources. A few approaches consider the scarcity of fossil energy resources only. No approach considers the scarcity of both renewable and non-renewable energy resources. In this paper, considerations for including physical energy scarcity of both renewable and non-renewable energy resources in life cycle impact assessment (LCIA) are discussed. Methods We begin by discussing a number of considerations for LCIA methods for energy scarcity, such as which impacts of scarcity to consider, which energy resource types to include, which spatial resolutions to choose, and how to match with inventory data. We then suggest three LCIA methods for physical energy scarcity. As proof of concept, the use of the third LCIA method is demonstrated in a well-to-wheel assessment of eight vehicle propulsion fuels. Results and discussion We suggest that global potential physical scarcity can be operationalized using characterization factors based on the reciprocal physical availability for a set of nine commonly inventoried energy resource types. The three suggested LCIA methods for physical energy scarcity consider the following respective energy resource types: (i) only stock-type energy resources (natural gas, coal, crude oil and uranium), (ii) only flow-type energy resources (solar, wind, hydro, geothermal and the flow generated from biomass funds), and (iii) both stock- and flow-type resources by introducing a time horizon over which the stock-type resources are distributed. Characterization factors for these three methods are provided. Conclusions LCIA methods for physical energy scarcity that provide meaningful information and complement other methods are feasible and practically applicable. The characterization factors of the three suggested LCIA methods depend heavily on the aggregation level of energy resource types. Future studies may investigate how physical energy scarcity changes over time and geographical locations.

Social Impact Analysis of Products under a Holistic Approach: A Case Study in the Meat Product Supply Chain

Social impact assessment of products can be approached through different methodologies that need to be adapted to the particularities and features of the studied subject. Thus, the Social Life Cycle Assessment methodology can be used to assess different innovative practices of product manufacturing, under a circular economy approach, by identifying potential positive as well as negative impacts along products’ life cycle. This paper presents the results of the Social Life Cycle Impact Assessment of a reference product from the Spanish meat industry using existing and new innovative methods of social impact analysis. Worker discrimination, health and safety for workers, consumers and local community were identified as the social aspects with relevant significance into the business or for the influence on customer’s perception of the products studied. Therefore, results can represent a reference scenario for the future assessment of innovative solutions in the Spanish meet sector. Despite the scarce use of Social Life Cycle Impact Assessment, this case study is a good example of how this innovative kind of assessment can be helpful for companies to identify their weak and strong social performance areas and design strategies to improve in Social Responsibility Management.

An overview of environmental impacts of lighting products at the end of life stage through life cycle impact assessment

Life Cycle Impact Assessment (LCIA) of lighting products is a methodology that analyses and evaluates environmental impacts throughout their total life cycle, from the extraction and processing of raw materials, design, construction, transportation, distribution, use, recycling and re-use of materials, and last their final disposal. According to the results of a large number of LCIAs, lighting products have a substantial environmental impact in multiple areas, as for example in primary energy, toxicological effects, the effect on global warming, the level of environmental acidification, etc. All of those impacts could result in more efficient products by enhancing the product design process (using Ecodesign). At the initial design stage of lighting products, the manufacturer should also take into consideration circular economy aspects at the End of Life stage (EoL) such as repair, reuse, remanufacturing, retrofitting, recycling, and upcycling and not only the energy savings from the use stage or the selection of raw materials. The scope of this paper is to collect and present an overview of all environmental impacts of LCIA analyses focusing at EoL stage of lighting products. Those impacts could be used as data input into a future model that determines which lighting products are more environmentally friendly.