Life cycle assessment of wood plastic decking manufacturing: Reduction of environmental impacts based on an industrial case study in China.

With the method of life cycle assessment, the paper takes Bayan County, Heilongjiang Province as the case to analyze the resources’ consumption and pollutant releasing of conventional and organic rice cultivation system in northeast China. On the basis of that, the comparative environmental assessment was accomplished. The results showed that the significant environmental impact factors are global warming potential, acidification potential, eutrophication potential and fresh water eco-toxicity potential. The environmental impact index of conventional rice is 5.24 in comparison with 4.15 for organic rice. If conventional rice were widely replaced by organic rice, acidification, eutrophication, human toxicity and fresh water eco-toxicity potential would be reduced by 47%, 32%, 85% and 67%. However, global warming and fossil energy consumption potential would increase 65% and 14%. In terms of environmental impact, organic rice is not totally superior to conventional rice. In the system of conventional rice cultivation, the agricultural materials period contributes most to environmental impact, occupying more than 60% in eutrophication, fresh water eco-toxicity, terra firma eco-toxicity, human toxicity, acidification and fossil energy consumption potential. In the system of organic rice cultivation, growing period contributes most to environmental impact, taking the place of the agricultural materials period. Thus, actualizing energy-saving and cleaner production in the fertilizer industry, promoting fair irrigation projects and optimizing fertilizer application are the key points to control the potential environmental impacts.

Due to the rise in clothing consumption per person and growing consumer awareness of environmental issues with products, the textile industry must adopt new practices for improving sustainability. The current study thoroughly investigates the benefits of using organic cotton fiber instead of conventional cotton fiber. Because of the extensive use of natural resources in the production of cotton, the primary raw material for textiles, which accounts for the environmental effects of a pair of jeans, a life cycle assessment methodology was used to examine these effects in four different scenarios. The additional scenarios were chosen based on the user preferences for washing temperatures, drying methods, and the type of cotton fiber used in the product. The environmental impact categories of global warming potential, eutrophication potential terrestrial ecotoxicity potential, acidification potential, and freshwater ecotoxicity potential were analyzed by the CML-IA method. The life cycle assessment results revealed that the lowest environmental impacts were obtained for scenario 4 with 100% organic cotton fiber with an improvement of 87% in terrestrial ecotoxicity potential and 59% in freshwater ecotoxicity potential. All of the selected environmental impacts of a pair of jeans are reduced in all scenarios when organic cotton is used. Additionally, consumer habits had a significant impact on all impact categories. Using a drying machine instead of a line dryer during the use phase is just as important as the washing temperature. The environmental impact hotspots for a pair of jeans were revealed to be the eutrophication potential, acidification potential, and global warming potential categories during the use phase, and the terrestrial ecotoxicity potential and freshwater ecotoxicity potential categories during the fabric manufacturing including cotton cultivation. The use of organic cotton as a raw material in manufacturing processes, as well as consumer preferences for washing temperature and drying methods, appears to have significant environmental impacts on a pair of jeans' further sustainable life cycle.

Environmental impact assessment of chicken meat production using life cycle assessment

The ecological floating beds (EFB) are widely used in water quality restoration because of its low cost, high efficiency, and green characteristics. However, there is a potential impact of the EFB on the environment while water purification is not in progress. In this study, the life cycle assessment (LCA) and life cycle cost (LCC) methods were used to evaluate the overall environment of mixed-fill and biofilm enhanced EFB. The results show that the total environmental impact of the mixed-fill ecological floating beds (MEFB) is greater than that of the biofilm ecological floating beds (BEFB). In the raw material acquisition and operational stages, the environmental impact of the MEFB is smaller than that of the BEFB, while the environmental impact of the MEFB during the construction phase is much greater than that of the BEFB. The environmental impact of the construction stage of the MEFB accounts for 98.3% of the environmental impact of the entire life cycle. The operational stage of the MEFB was eco-friendly with regard to eutrophication potential, photochemical oxidation potential, ozone layer depletion potential, human toxicity potential, freshwater aquatic eco-toxicity potential, and terrestrial eco-toxicity potential environmental impact, and these effects of the operational stage of the MEFB account for 45.5% of the total environmental impact. The impact of the BEFB on the environment during raw material acquisition, construction, and operation accounts for 46.7%, 37.7%, and 15.6%, respectively, of the entire life cycle impact. Both two EFB technologies, the capital cost was the main expenditure with LCC, accounting for 60.4% and 52.9% of the MEFB and BEFB, respectively.

A comparative Life Cycle Assessment (LCA) of solar photo-Fenton and solar photoelectro-Fenton, two solar-driven advanced oxidation processes (AOPs) devoted to the removal of non-biodegradable pollutants in water, is performed. The study is based on the removal, at laboratory scale, of the amino acid α-methylphenylglycine, a good example of soluble and non-biodegradable target pollutant. The system under study includes chemicals, electricity, transport of all raw materials to the plant site, and the generation of emissions, but it does not take into account the impact of the infrastructure needed to build a hypothetical solar plant. Nine environmental impact categories are included in the LCA: global warming potential, ozone depletion potential, aquatic eutrophication potential, acidification potential, human toxicity potential, photochemical ozone formation potential, fresh water aquatic ecotoxicity potential, marine aquatic ecotoxicity potential, and terrestrial ecotoxicity potential and abiotic resource depletion potential. Although previous experimental results show that both AOPs are able to efficiently degrade the pollutant, the LCA indicates that solar-driven photo-Fenton is the most environmentally friendly alternative, mainly because the use of electricity in solar photoelectro-Fenton experiments involves high environmental impacts.

PURPOSE: An osmotic microbial fuel cell (OsMFC) is derived from the integration of a forward osmosis (FO) membrane into a conventional microbial fuel cell (MFC), with enhanced performance in bioelectricity generation from organic matter and recovery of high-quality water. The environmental impacts of this newly developed technology, however, have not been studied. To understand and potentially reduce the environmental impacts of the OsMFC technology, the environmental impacts have been assessed. METHODS: An attributional life cycle assessment (LCA) model has been developed to evaluate the cradle-to-grave environmental impacts of the OsMFC based on a lab-scale prototype. The International Life Cycle Data System (ILCD) method has been applied to calculate and characterize the environmental impacts of treating 1 L of water by using the OsMFC technology in GaBi 8.7. Sensitivity and scenario analyses have been employed to assess the environmental impact variations based on changing power densities and different disposal methods, respectively. RESULTS AND DISCUSSION: The results indicate that several factors including raw material extraction, system operation, and end-of-life (EoL) stages have relatively large impacts in certain categories. The raw material extraction and system operation take up 50.04% and 32.06% of global warming potential (GWP), respectively. The EoL expends 98.02% of ecotoxicity potential (ETP), 54.31% of eutrophication potential (EP), and 52.24% of human toxicity potential (HTP). A comparison of the OsMFC with other bioelectrochemical systems (BESs) reveals that it has higher GWP due to the polymethylmethacrylate (PMMA) sheeting used to construct the cell and the stainless steel used to build the cathode electrode, but comparable acidification potential (AP), eutrophication potential (EP), ozone depletion potential (ODP), and respiratory inorganics (RI). The greenhouse gas (GHG) emissions of the OsMFC are also benchmarked with those of the conventional wastewater treatment methods, and it shows that the OsMFC has higher GHG emissions than the conventional wastewater treatment methods at the current power density. However, the results may change dramatically with the change of materials and cell configurations. CONCLUSIONS: According to the analysis, cell materials, cell configuration, electricity usage during the operation stage, and disposal methods are major problems to solve in the development of the OsMFC technology. Enhancement of power density and alternation of cell materials and configuration may turn out to be effective methods to alleviate the environmental impacts and increase market competitiveness of the OsMFC technology in the future.

Life cycle assessment on polylactide-based wood plastic composites toughened with polyhydroxyalkanoates

This study reported life cycle assessment (LCA) of six copper mines in Australia, Papua New Guinea and Portugal. Inventory data was sourced from published papers, sustainability reports by mining companies, independent technical reports and previous CSIRO studies. SimaPro software and various databases were used to evaluate life cycle based environmental impacts. The impact indicators were: global warming potential (GWP), acidification potential, water footprint, ecotoxicity potential, ozone depletion potential and human toxicity potential (carcinogenic and non-carcinogenic), abiotic resource depletion potential (minerals and fossil fuels), particulate matter and ionizing radiation. Generally, open pit mines were found to have a GWP of approximately 1.0 t CO2-eq/t Cu concentrate while underground mines had approximately 1.3 to 1.8 t CO2-eq/t Cu concentrate. Environmental impacts varied between mines considerably due to several factors, most notably: ore grade, mining method, flowsheets and ore mineralogy. Energy consumption and sources were significant contributors to most impact categories.

The EU is one of the largest producers and consumers of wood pellets in the world, covering around 36% of the global wood pellet production and around 50% of the global consumption in 2018. The EU wood pellet consumption is expected to further increase in response to the ambitious energy and climate goals for 2030. Currently, wood pellets are mainly produced from sawdust and other sawmill residues; however, other types of forest feedstock are being investigated in order to meet the increasing wood pellet demand and move toward greater energy independence. The aim of this study is to evaluate and compare the environmental impact of different wood pellet supply chains. A comparative cradle-to-grave life cycle assessment is performed considering the following wood feedstock systems: (i) sawdust from sawmill (S1), (ii) roundwood logs (S2), (iii) whole trees from forest thinning operation (S3), and (iv) logging residues produced during forest tree harvesting (S4). The study focuses on Global Warming Potential (GWP), Ozone Depletion Potential (ODP), Photochemical Ozone Creation Potential (POCP), and Human Toxicity Potential (HTP). Results show that S3 displays the lowest figures on all the environmental impact categories considered in this study. Compared to the reference case S1, S3 shows a GWP reduction of 46%, an ODP reduction of 6.6%, a POCP reduction of 14.8%, and HTP reduction of 13.2%. S3 and S4 have lower GWP than S1 and S2, even when the biogenic CO2 emissions are considered. Overall, the life cycle phases that have the highest GWP, POCP, and HTP are the burning phase and the preparation of the material to be pelletized, particularly the drying process. Nevertheless, the main phases that contribute to the ODP are the forest operations and the pellet preparation.

Environmental life cycle assessment of seafood production: A case study of trawler catches in Tunisia

Experimental, economic and life cycle assessments of recycling end-of-life monocrystalline silicon photovoltaic modules

ENVIRONMENTAL SYSTEM ANALYSIS FOR HORTICULTURAL CROP PRODUCTION

The sustainability of agricultural production is a key issue, particularly in terms of fertilizer use, greenhouse gas emissions, and resource depletion. This study uses life cycle assessment (LCA) to compare the environmental impacts of composted and pelletized poultry manure (CPPL) and six different fertilizers (ammonium nitrate (AN), calcium ammonium nitrate (CAN), urea, monoammonium phosphate (MAP), triple superphosphate (TSP), and potassium chloride (KCl)) during corn and winter wheat production, as well as their impact on broiler chicken production. The study also took into account different fertilization methods and seasonal variations (summer and winter rotation), analyzing eleven environmental impact categories, including global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), abiotic resource use (abiotic depletion potential for elements (ADPe), abiotic depletion potential for fossil fuels (ADPf)), ozone layer depletion potential (ODP), photochemical oxidation potential (POP) and ecotoxicity potentials (freshwater aquatic ecotoxicity potential (FAETP), human toxicity potential (HTP), marine aquatic ecotoxicity potential (MAETP), terrestrial ecotoxicity potential (TETP)). Based on the results, GWP was 11%–14% lower for CPPL production compared to fertilizers, while ADPf was 14%–56% lower. At the same time, AP was significantly higher for CPPL, mainly due to ammonia emissions. In crop production (corn, winter wheat), CPPL-based nutrient replenishment resulted in 11%–34% lower GWP and 14%–56% lower ADPf in most environmental scenarios compared to fertilizer treatments. In toxic impact categories (e.g., FAETP, MAETP), reductions of 3%–15% were observed. However, AP values were 2.6%–6.8% higher, and EP could be up to twice as high as for fertilizer treatments. In broiler chicken farming, when feed was produced from CPPL-grown crops, the environmental impact was 30%–85% lower in almost all categories examined than with fertilizer-based feed. Seasonal differences were moderate, with a 3%–5% increase in some categories during winter. Based on the results, CPPL offers a promising alternative to chemical fertilizers, especially in reducing greenhouse gas emissions and nutrient leaching. In line with circular economy principles, CPPL can contribute to the development of more sustainable agricultural systems.

Life cycle assessment on PERC solar modules

In China, the evaluation mechanism of cleaner production schemes is characterized with flaws and lacks quantitative evaluation methods, which are the key technical aspects in cleaner production audit. This paper is based on a combination of life cycle assessment (LCA) and cost analysis methods to evaluate cleaner production schemes in the iron making industry. Eight environmental impact categories, including Acidification Potential, Eutrophication Potential, Freshwater Aquatic Ecotoxicity Pot, Global Warming Potential, Human Toxicity Potential, Marine Aquatic Ecotoxicity Potential, Photochemical Ozone Creation Potential, and Terrestric Ecotoxicity Potential, are chosen to analyze the environmental impact of the iron making industry. The results show that the greatest contribution factor to the iron making industry is the blast furnace process. The most significant environmental impact category is Global Warming Potential. According to the results, we proposed 14 cleaner production schemes. LCA is used to evaluate the environmental performances of 14 cleaner production schemes, which conclude that the scheme of “the use of recycled water” increases environmental impacts, while the other 13 cleaner production schemes result in environmental benefits. Meanwhile, the cost analysis based on payback period, net present value and internal rate of return indicates that the 13 schemes are economically feasible. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 195–203, 2016