Impact Categories Global Warming Research Articles

Hybrid Life Cycle Assessment (LCA) of prefabrication: A comparison of conventional and mixed reality-based solutions

Conventional prefabrication in construction is causing distinct challenges, including environmental pollution and high energy usage. However, integrating emerging technologies such as Mixed Reality (MR) in prefabrication is expected to mitigate the environmental impacts and improve overall sustainability. This study evaluates and analyses the environmental benefits and burdens associated with implementing MR technologies in prefabrication compared to conventional prefabrication. The production stages in prefabrication, including reinforcement, side formworks, concreting, and human labor, have been identified as primary unit processes, and their respective contributions to the overall environmental impact have been assessed. A comprehensive assessment using a hybrid Input-Output Life Cycle Assessment (IO-LCA) model, while incorporating human labor hours is necessary for a thorough environmental assessment. The cradle-to-gate LCA results of a declared unit of 1 m3 volume of conventional prefabrication are compared with MR-enabled prefabrication. The results show that using MR technology in prefabrication significantly decreases the environmental burdens of the prefabrication in impact categories of Global warming (8%), Terrestrial acidification (8%), Marine eutrophication (10%), and Stratospheric ozone depletion (17%). Furthermore, with the higher levels of MR implementation, there is a significant reduction (around 60%) in the environmental impact associated with prefabrication. Accordingly, the contribution of MR technology in designing, planning, monitoring, assembling, and collaborating in prefabrication leads to effective resource management, minimization of waste, and enhancement of overall efficiency. The reinforcement process has notably elevated environmental impact in prefabrication while recognizing the improvement opportunities through MR implementation. MR-enabled quality inspection is of great importance in significantly reducing environmental burdens.

Study of Environmental Impact Improvement for Fish Feed Production Companies

The national fish consumption increases from 2020 to 2021 of 1.10%. The practices of fish feed production have direct environmental impacts related to emissions to air, water, and soil. The fish feed production process is divided into several stages including the intake, fine grinder, mixer, press, post pellet, dryer, cooler, sieveter, bagging off, and boiler. Considering the environmental impacts from fish feed production activities, there is a need for analysis of those impacts using the LCA method. LCA includes four stages: goal and scope definition, LCI, LCIA, and interpretation. This research is limited to the fish feed production process (gate to gate) and is based on the impact category method ReCiPe 2016 (H) with a midpoint characterization factor. Subsequently, determining environmental improvement program recommendations based on LCA study results and the AHP. The results of the LCA analysis on fish feed production indicate that the production of 1 ton of fish pellets generates 13 impact categories using the ReCiPe 2016 (H) midpoint method. The hotspot in the fish feed production process are found in the boiler unit with the global warming impact category (487,5868956 kg CO? eq/ Ton of fish pellets) and the WWTP with the freshwater eutrophication impact category (0,0003883 kg P eq/Ton of fish pellets). The global warming impact is influenced by the emission inventory of CO2, CH4, and N2O, while the freshwater eutrophication impact is influenced by the inventory data of COD and BOD5.

Life Cycle Assessment of Bioenergy Production Using Wood Pellets: A Case Study of Remote Communities in Canada

In remote communities of Canada, diesel is the primary source of electricity and heat. Promoting sustainable and diverse means of heat and power generation is essential to providing reliable and less carbon-intensive energy supply to remote communities. Among renewable energy sources in Canada, biomass is a major source of energy, with wood pellets being a notable contributor. In this study, using wood pellets in a remote community of Canada is investigated using life cycle analysis (LCA). Furthermore, wood pellet combustion is compared with diesel combustion, the most common fossil fuel in these regions. SimaPro (version 8.4.0.0) was used with Ecoinvent 3 as the primary library because of the nature of the feedstock. Harvesting, transportation, sawmill operation, pelletization, and combustion stages are considered in LCA. In doing so, first, life cycle data related to each of these stages are collected with respect to eight impact categories of global warming, ozone depletion, carcinogenic, non-carcinogenic, smog, respiratory effects, acidification, eutrophication, ecotoxicity, and fossil fuel depletion. The results indicate that pelletization and combustion stages have the greatest environmental impact, specifically in terms of non-carcinogenic effects from pelletization and respiratory effects from pellet combustion. Additionally, when comparing wood pellets to diesel, wood pellet combustion exhibits superior performance across various impact categories, particularly in non-carcinogenic effects.

Cradle to gate environmental impact assessment of the Iranian forestry operations

This study conducts the first cradle-to-gate life cycle assessment (LCA) study on forestry operations in Iran and provides comprehensive regionalized life cycle inventory (LCI) data on the Iranian forest sector. This LCA employs midpoint and endpoint impact categories based on the IMPACT 2002+ method in addition to the cumulative exergy demand (CExD) indicator. The results of this study show that fuel consumption in harvesting machinery and fertilizer application in reforestation are two sources of direct emissions that contribute to different environmental impact categories. Transportation is the main hotspot in most midpoint environmental impact categories, such as global warming, or endpoint categories, such as human health. The total exergy removed from nature to produce 1 t of wood as logs is about 978 MJ-eq, accounting for 7.7% of the energy content in 1 t of wood. The global warming impact category equals 58 kg CO2-eq or 5.4% of the total CO2-eq contained in 1 t of wood as logs. The environmental performance of the system could be improved by expanding local clients rather than clients from other regions and upgrading inefficient machinery. Gains are also possible by conducting a comparative LCA analysis of different adaptable forest management strategies and harvesting methods compared to the business-as-usual approach in the Iranian forestry sector.

Environmental life cycle assessment of treatment and management strategies for food waste and sewage sludge

A consequential life cycle assessment (LCA) was utilized to compare the environmental impacts of food waste and sewage sludge management strategies. The strategies included a novel two-phase anaerobic digestion (AD) system and alternatives including landfill, waste-to-energy, composting, anaerobic membrane bioreactor, and conventional AD (wet continuous stirred-tank reactor [CSTR]). The co-management of food waste with sewage sludge was also considered for the two-phase AD system and for a conventional AD reactor. A multidimensional LCA approach was taken, considering the five-midpoint impact categories of global warming, smog, human health particulate, acidification, and eutrophication estimated using the U.S. EPA Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts. Co-management of food waste and sewage sludge using the novel two-phase AD system was shown to maximize energy recovery and had a net global warming benefit while reducing other environmental impacts compared with the alternative management strategies. It had similar relative environmental advantages across all categories as conventional AD, with the advantage of a smaller physical footprint. However, both approaches featured net environmental burdens when the background electric grid intensity fell below 0.25 kg CO2-eq kWh−1, as could be expected in a decarbonized electric future. Upgrading the biogas produced from AD to renewable natural gas can displace the use of fossil natural gas for other non-electricity energy requirements that are difficult to decarbonize and may extend the time period of significant environmental benefits of utilizing AD for organic waste management. Treatment of the nutrient-rich supernatant generated by the novel two-phase AD system could be an obstacle for utilities with stringent nutrient discharge limits. Future research and full-scale implementation are needed to demonstrate the benefits of the two-phase AD system predicted through this analysis.

Identifying the environmental hotspots of sulfur-free odorant for LPG storage and filling by life cycle approach

The main objective of this study is to determine the potential environmental impact of storage and filling the liquefied petroleum gas (LPG) with sulfur-containing (ethyl mercaptan) and sulfur-free (Greenodor) odorants by comparative life cycle assessment (LCA). The LCA was carried out within the scope of ISO 14040 and 14044 Standards in a facility that stores and fills LPG and potential environmental impact was calculated for eleven different impact categories. According to the characterization results, it was determined that the overseas transportation process had the highest impact among all impact categories. Because environmental impact was suppressed by other processes in characterization results due to the very low inclusion of the odorants in LPG, the percentage contribution of consumption of both odorants was compared and it was revealed that Greenodor had a lower environmental impact in all mid-point impact categories. For both tanker and cylinder filling, the impact category with the highest difference was photochemical oxidation with a rate of 79 %. The lowest difference was found in the global warming impact category with 18 % for tanker filling and 19 % for cylinder filling. Considering uncertainty analysis results for LPG tanker filling, Greenodor preceded ethyl mercaptan for all mid-point categories. However, in terms of LPG cylinder filling, there was no significant difference between two odorants.

Life Cycle Assessment of Natural Zeolite-Based Warm Mix Asphalt and Reclaimed Asphalt Pavement

Today, an important part of paved surfaces in the world uses asphalt mixtures. This practice increases the use of aggregates and fossil fuels, the availability of which is limited. Most of the studies referring to asphalt mixtures reported and compared the mechanical performances without detailing the environmental impacts of the different technologies proposed. The objective of this study was to present and compare through a life cycle assessment using a “cradle-to-gate” approach of different types of asphalt mixtures designed for the same performance, hot mix asphalt (HMA) as a control sample, and warm mix asphalt (WMA) using natural zeolite, Evotherm® and reclaimed asphalt material (RAP) in different proportions. The analysis was performed using SimaPro 9 software, using the ReCiPe method version 1.11. For the comparison of the environmental impacts, 1 ton of asphalt mixture was used as a functional unit. The most relevant results show that the use of natural zeolite or Evotherm® helps to reduce environmental impacts. In the global warming impact category, the decrease between the standard HMA and a mix with RAP and natural zeolite was 8%, while in the fossil fuel depletion, the decrease was 13%.

Environmental assessment of a single-family photocatalytic greywater treatment system based on the design and operating conditions

A life cycle assessment was carried out to compare the environmental impacts of an alternative water supply for toilet flushing in households with those of water currently supplied for this purpose through the municipal potable water network. In the proposed system, greywater from showers, baths and wash-hand basins is collected and treated using heterogeneous TiO2 photocatalysis. Several scenarios comprising different design and operating conditions were studied. Using the ReCiPe (H) 2016 method, the following environmental impact categories were assessed: global warming, stratospheric ozone depletion, terrestrial acidification, freshwater eutrophication, marine eutrophication, human carcinogenic toxicity, human non-carcinogenic toxicity, terrestrial ecotoxicity, freshwater ecotoxicity, marine ecotoxicity, and water consumption. The results show that for the water reuse device to be less impactful than the municipal water system in at least 7 of the selected impact categories by more than 20 %, the product between the number of reactors and the operating time should not exceed 8 reactors·h·day−1, also taking the influence of the UVA-LED's power into account. Of the 18 alternative scenarios analyzed, 14 present a potential for reducing the environmental impacts compared to the municipal water supply system in at least 7 of the 11 evaluated environmental impact categories. For instance, the municipal supply of one cubic meter of water and its subsequent wastewater treatment in the baseline scenario produces 4.21 kg CO2 eq·m−3, whereas only 1.62 kg CO2 eq·m−3 are produced in the optimum scenario of the greywater reuse system. Moreover, the use of solar photovoltaic panels as a source of electricity for the systems is found to be an effective measure to further improve the environmental performance, mainly for the impact categories of global warming, stratospheric ozone depletion, and terrestrial acidification. The study also highlights the benefits of recycling components and materials in the end-of-life stage of the proposed system.

Life cycle assessment of bioelectrochemical and integrated microbial fuel cell systems for sustainable wastewater treatment and resource recovery

Bioelectrochemical system (BES) is an emerging technology that can treat wastewater via microbial activity while producing energy simultaneously. The system can couple with conventional systems to improve system performance. This study aims to compare the environmental performance of BES and the integrated microbial fuel cell (MFC) systems via a life cycle assessment methodology and identify the major environmental hotspots of the system. Fifteen treatment options are assessed with the ReCiPe 2016 characterization method using SimaPro 9.2 software. The results show double chamber air-cathode microbial electrolysis cell (MEC1) and membrane distillation integrated MFC (MD + MFC) treatment options present as the most environmental favourable among the BES and integrated MFC systems, respectively, due to the offset of the environmental loads from the avoided impacts contributed by their value-added by-product, which is hydrogen fuel for MEC1 and tap water for MD + MFC. Electricity consumption dominates the environmental loads of all the BES options for up to 90% of the global warming impact category. The environmental benefits from the electricity generation of BES are minor (i.e., MFC: 0.01–2% while microbial desalination cell: 0.01–7% of the total environmental impact in a system) to offset the environmental loads incurred by the system. Platinum-based cathode incurs 2.5–24 times higher environmental burdens than non-platinum configurations in MFC under the human carcinogenic toxicity impact category. In line with Sustainable Development Goals 6 and 13, this study provides scientific references to wastewater treatment stakeholders in selecting suitable BES and integrated MFC systems to improve water sanitation and address climate change simultaneously.

Cascading Crypthecodinium cohnii Biorefinery: Global Warming Potential and Techno-Economic Assessment

Prior to the commissioning of a new industrial biorefinery it is deemed necessary to evaluate if the new project will be beneficial or detrimental to climate change, one of the main drivers for the sustainable development goals (SDG) of the United Nations. In particular, how SDG 7, Clean and Efficient Energy, SDG 3, Good Health and Well Being, SDG 9, Industry Innovation and Infrastructure, and SDG 12, Responsible Production and Consumption, would engage in a new biorefinery design, beneficial to climate change, i.e., fostering SDG 13, Climate Action. This study uses life cycle assessment methodology (LCA) to delve in detail into the Global Warming Impact category, project scenario GHG savings, using a conventional and a dynamic emission flux approach until 2060 (30-year lifetime). Water, heat and electricity circularity are in place by using a water recirculation process and a combined heat and power unit (CHP). A new historical approach to derive low and higher-end commodity prices (chemicals, electricity, heat, jet/maritime fuel, DHA, N-fertilizer) is used for the calculation of the economic indicators: Return of investment (ROI) and inflation-adjusted return (IAR), based upon the consumer price index (CPI). Main conclusions are: supercritical fluid extraction is the hotspot of energy consumption; C. cohnii bio-oil without DHA has higher sulfur concentration than crude oil based jet fuel requiring desulfurization, however the sulfur levels are compatible with maritime fuels; starting its operation in 2030, by 2100 an overall GHG savings of 73% (conventional LCA approach) or 85% (dynamic LCA approach) is projected; economic feasibility for oil productivity and content of 0.14 g/L/h and 27% (w/w) oil content, respectively (of which 31% is DHA), occurs for DHA-cost 100 times higher than reference fish oil based DHA; however future genetic engineering achieving 0.4 g/L/h and 70% (w/w) oil content (of which 31% is DHA), reduces the threshold to 20 times higher cost than reference fish oil based DHA; N-fertilizer, district heating and jet fuel may have similar values then their fossil counterparts.

Comparative evaluation of different operation scenarios for a full-scale wastewater treatment plant: Modeling coupled with life cycle assessment

All inputs and outputs of a technical system can be interpreted from an environmental point of view and some modifications, that are less harmful to the environment, can be incorporated into the system by using the life cycle assessment (LCA) approach. The energy footprint of wastewater treatment plants (WWTPs) is one of the most important environmental indicators. The sustainability of wastewater treatment systems can be evaluated in terms of energy consumption based on LCA. The aim of this study was to determine the environmental performance of a biological nutrient removal (BNR) plant in conjunction with mathematical modeling and the LCA approach based on three scenarios, which would reduce the net electricity consumption of the treatment plant by 10%. Three scenarios were constructed by the combinations of different values in dissolved oxygen (DO) concentration, sludge retention time (SRT) and internal recirculation (IR) parameters. A mathematical modeling study was carried out in order to determine the values of those parameters that decreased the net electricity consumption by 10%. Scenario 0 was developed based on a reference WWTP with default DO concentration, SRT and IR. The pairs of SRT and IR; SRT and DO; IR and DO were analyzed in Scenario 1, 2 and 3, respectively. The results showed that the global warming impact category has approximately the same values in Scenario 0 and Scenario 1 and these scenarios have the best performances in this category. Scenario 0 is also the best environmental performing with respect to marine eutrophication, while it has the highest environmental loads in terrestrial ecotoxicity and fossil resource scarcity categories. In freshwater eutrophication, Scenario 1 has the best environmental performance while the highest environmental burden in marine eutrophication is occurred in Scenario 1. Moreover, Scenario 1 and Scenario 2 have the same values and the worst environmental performances in the terrestrial acidification impact category. Scenario 1 and 2 have much better performances in fossil resource scarcity impact than in other scenarios while Scenario 2 is the worst environmental performing with respect to the global warming besides terrestrial acidification. Scenario 3 has a worse environmental performance in the freshwater eutrophication category in comparison to other scenarios, while it has the best environmental performances in the terrestrial acidification and terrestrial ecotoxicity categories. Scenario 1, 2 and 3 have better environmental performances in energy-related impact categories compared to the baseline scenario.

4대 공작기계 재제조에 대한 LCA 분석을 통한 환경부하 및 온실가스 저감효과 분석

The industrial sector that can actively respond to the circular economy is remanufacturing. In the case of machine tools, the need for remanufacturing of machine tools is emphasized because it is expected that waste products will increase before the mechanical life expires due to the change in perception of low carbon energy reduction and the increase in demand for advanced high-precision machine tools due to the development of ultra-precision industry. This study calculated the environmental load and greenhouse gas reduction effects through LCA analysis of the remanufacturing of four major machine tools used throughout the industry, such as grinding machines, planar millers, presses, and lathes, using LCA. Due to the nature of the remanufacturing process, some consumables are replaced or put in to improve quality and function by using the core of the product (or part) after use. In the case of cores used in the remanufacturing process, environmental impacts have already occurred during manufacturing by new manufacturers. In remanufacturing, only the environmental impacts caused by the use of newly input auxiliary materials and energy, excluding cores, occur. As a result of the Midpoint LCA analysis, the amount of reduction in environmental impact for each product remanufactured were 4,439 kg CO2 eq. per machine based on the global warming impact category during characterization, the planar miller 90,080 kg CO2 eq., the press 636,390 kg CO2 eq., the lathe 24,638 kg CO2 eq., it was found that the reduction of environmental impact was the highest when one press was remanufactured.

Environmental Performance of Alternative Green Polyol Synthesis Routes: A Proposal for Improvement

This study verified the environmental effectiveness of potentially less aggressive routes for the synthesis of poly(propylene/ethylene oxide) glycol (PPG). The analysis was developed in two stages. Firstly, the environmental performance of the conventional PPG processing route was compared to alternative variants—vegetal PPG and CO2-based PPG—applying the life cycle assessment technique to measure the primary energy demand, global warming potential, acidification, photochemical oxidation, and freshwater ecotoxicity impact categories. The synthesis of vegetable polyols from bio-based assets, such as vegetable oils, and the application of CO2 conversion routes as an alternative to technologies supported by petroleum and natural gas were studied. The use of CO2 recovered through carbon capture and usage practices resulted in environmental gains for PPG production. The processing routes within vegetal assets were not an environmentally attractive option as the performance was worse than the conventional arrangement by 144% for the global warming impact category, an increase related to the deforestation carried out to expand soybean cultivation in Brazil. Secondly, improvement scenarios to mitigate the environmental impacts of alternative routes were performed. The hypothesis of using cleaner inputs to obtain a more ecofriendly route was tested. The analysis concluded that the use of high-purity CO2 brings fewer benefits compared to other capturing sources that need a purification process before feeding the PPG synthesis.

Energy, economic, and environmental assessment of the integrated production of palm oil biodiesel and sugarcane ethanol

The key objective of this study was to evaluate and compare, within the concept of integrated biorefining, the potential environmental gains of the life cycle, economic feasibility and energy balance of the production of bioenergetics from palm and sugarcane. In this context, the research model developed in this work involved several assessment techniques; in terms of environmental assessment, the tool used was the Life Cycle Assessment (LCA) from the Well-To-Tank perspective, which is based on the LCA “cradle-to-gate” assignment method. The environmental assessment was performed using SimaPro v.8.0.3 software and the impacts were quantified using the IMPACT 2002+ method. On the other hand, energy performance evaluation was based on the 1st law indicators. Likewise, economic feasibility was based on the evaluation of the fixed capital investment index and the estimate of investment costs for the entire integrated system. Two different scenarios were proposed in order to compare and evaluate traditional systems with the integrated biorefinery. The first conversion scenario (baseline scenario) consisted of a traditional palm oil extraction plant in addition to an ethanol and sugar plant, concerning the use of fossil fuels in all stages of production. The second conversion scenario (improved scenario) explored the substitution of fossil energy sources as well as the energy recovery of residual biomass in more efficient energy conversion systems. The results indicated significant reductions of 29.5% and 29.1% in the global warming impact category when the baseline scenario was compared to the improved scenario. Additionally, the improved scenario achieved a reduction of 2.1 g CO2eq MJ−1 (ethanol) and 2.61 g CO2eq MJ−1 (biodiesel). On the other hand, the improved scenario presented better energy rates since it showed an increase of 3.82% in the global efficiency of the system and produced 106.32 kWh more per ton of processed raw material. Finally, when considering the Life Cycle Energy Efficiency, an increase of 83% was observed and in the case of the Renewability Factor showed an increase of 7.12 energy units. Integration is also economically feasible; however, it could be significantly improved through fiscal incentives founded on the reduction of fossil energy use, enhanced conversion yielding, and improvements in conversion technologies.

Life cycle assessment for algae-based desalination system

To clearly understand the environmental impacts of algae-based desalination system, a life cycle assessment is undertaken by comparing four different scenarios: (1) multi-stage microalgae based desalination system without algal biomass reuse; (2) multi-stage microalgae based desalination system with algal biomass reuse; (3) hybrid desalination system with microalgae as the pre-treatment for Low Pressure Reverse Osmosis; and (4) conventional Seawater Reverse Osmosis system. It is suggested that scenarios 2 and 4 have the overall lowest and highest environmental impacts, respectively. This phenomenon is probably caused by the lower energy consumption and lower operational and maintenance requirements of high rate algal pond system. Furthermore, scenario 2 considers the algal biomass reuse to generate electricity through anaerobic digestion, which could offset the environmental impacts. It is also identified that the operational phase contributes approximately 50–60% of the total environmental impact in most impact categories for algae-based desalination system, however, the operational phase contributes around 70–80% of the total environmental impact for membrane based desalination system. A sensitivity study is undertaken to evaluate the effects of three key design parameters on environmental impact in global warming impact category. It is identified that the total dissolved solids removal efficiency of high rate algal pond plays the most important role in determining the potential environmental impacts of different scenarios. This study clearly shows that scenario 2 of multi-stage microalgae based desalination system with algal biomass reuse is the most environmentally friendly desalination approach.

Gasification of Woody Biomasses and Forestry Residues: Simulation, Performance Analysis, and Environmental Impact

Wood and forestry residues are usually processed as wastes, but they can be recovered to produce electrical and thermal energy through processes of thermochemical conversion of gasification. This study proposes an equilibrium simulation model developed by ASPEN Plus to investigate the performance of 28 woody biomass and forestry residues’ (WB&FR) gasification in a downdraft gasifier linked with a power generation unit. The case study assesses power generation in Iceland from one ton of each feedstock. The results for the WB&FR alternatives show that the net power generated from one ton of input feedstock to the system is in intervals of 0 to 400 kW/ton, that more that 50% of the systems are located in the range of 100 to 200 kW/ton, and that, among them, the gasification system derived by tamarack bark significantly outranks all other systems by producing 363 kW/ton. Moreover, the environmental impact of these systems is assessed based on the impact categories of global warming (GWP), acidification (AP), and eutrophication (EP) potentials and normalizes the environmental impact. The results show that electricity generation from WB&FR gasification is environmentally friendly for 75% of the studied systems (confirmed by a normalized environmental impact [NEI] less than 10) and that the systems fed by tamarack bark and birch bark, with an NEI lower than 5, significantly outrank all other systems owing to the favorable results obtained in the environmental sector.

Environmental impact of a new concept of food service: A case study for the re-use of naval shipping containers

This study aims to evaluate the environmental sustainability of a new street food format for food service based on the re-use of naval shipping containers and to compare it with the conventional one (street food truck). The environmental impact analysis was performed using the Life Cycle Assessment methodology. The functional unit (FU) was identified in the food service, including three food preparations: a dish of pasta (100 g), one sandwich (150 g) and one portion of fries (200 g). Following a “from cradle to gate” approach, the factors studied are: (i) the customization of a shipping container in a street food format, (ii) the construction and use of the cooking appliance, (iii) the logistics, (iv) the cooking phase (including final packaging as food cup). The life cycle of ingredients for food preparations has been neglected due to the variability of the products.The results show that the two higher hotspots are electricity consumed by cooking appliance (35%) and oil used to fry (34%), attributable only to the fries preparation. The third hotspot is imputable to the customized structure, with an average percentage value equal to 15%. Considering the global warming impact category, the customization into a street food format release 1280 kg CO2eq, while the production of a new container or a new street food truck format implies the emission of 12,800 kg CO2eq and 20,900 kg CO2eq respectively. The impact of the customized container (re-used container) weight for 0.04 kg CO2eq/FU, this value increases 11.6 times for a new container street food format, and 17 times for a new street food truck format.Overall, quantifying the environmental damage, the results showed how the re-use of a naval shipping container can be a way to reduce the environmental impact of food preparation, avoiding dismissing or building activity of the structure reducing the impact of the structure of about 95% offering a more sustainable street food services.

Comparative life-cycle assessment of a mass timber building and concrete alternative

The US housing construction market consumes vast amounts of resources, with most structural elements derived from wood, a renewable and sustainable resource. The same cannot be said for all nonresidential or high-rise buildings, which are primarily made of concrete and steel. As part of continuous environmental improvement processes, building life-cycle assessment (LCA) is a useful tool to compare the environmental footprint of building structures. This study is a comparative LCA of an 8360-m2, 12-story mixed-us apartment/office building designed for Portland, OR, and constructed from mainly mass timber. The designed mass timber building had a relatively lightweight structural frame that used 1782 m3 of cross-laminated timber (CLT) and 557 m3 of glue-laminated timber (glulam) and associated materials, which replaced approximately 58% of concrete and 72% of rebar that would have been use in a conventional building. Compared with a similar concrete building, the mass timber building had 18%, 1% and 47% reduction in the impact categories of global warming, ozone depletion, and eutrophication, respectively, for the A1-A5 building LCA. The use of CLT and glulam materials substantially decreased the carbon footprint of the building, although it consumed more primary energy compared with a similar concrete building. The impacts for the mass timber building were affected by large amounts of gypsum board, which accounted for 16% of the total building mass. Both lowering the amount of gypsum and keeping the mass timber production close to the construction site could lower the overall environmental footprint of the mass timber building.

Environmental burdens of the comprehensive utilization of straw: Wheat straw utilization from a life-cycle perspective

Agricultural straw utilization has become a big concern in many countries with abundance of the production. While different comprehensive utilization methods have been proposed, the environmental aspects of these methods need to be examined to reduce the environmental burdens of agricultural straw disposal. By deploying life cycle assessment, this article evaluates the environmental impact of different wheat straw utilization methods, including soil incorporation, open burning, indoor incineration with energy recovery, combined electricity and energy recovery, conventional straw pulping, and a new type of straw pulping. The results show that the new type of straw pulping has the best environmental performance, while open burning has the worst. The performance of the new type of straw pulping is mainly attributed to its substitution for sulphate pulp and chemical fertilizers. New type of straw pulping has the best environmental performance for human health, ecosystem quality and resource impact categories, with corresponding −2.08E-03 DALY (Disability-Adjusted Life Years), −1.50E+03 PDF·m2·y (Potentially Disappeared Fraction of species over a certain amount of m2 during a certain amount of years) and −7.75E+03 MJ (Mega Joules) for these three impact categories. While soil incorporation has the smallest environmental impact in global warming impact category, with 2.33E+02 kg CO2-eq. Sound management of agricultural straw should combine different utilization methods. Policy interventions, such as high-quality straw leaving the field, are needed to deal with the substantial generation of agricultural straw.

PET bottles recycling in China: An LCA coupled with LCC case study of blanket production made of waste PET bottles

A large number of polyethylene terephthalate (PET) bottles are discarded daily after usage. Thus, plastic bottle recycling has elicited considerable attention in recent years. In this context, this study aims to quantify the environmental and economic impacts of blanket production from 100% recycled waste plastic bottles in China through a life cycle assessment coupled with life cycle costing method. In addition, the environmental impact of replacing coal with natural gas and solar energy was evaluated. Results show that impact categories of global warming and fossil depletion have significant influence on the overall environment. Carbon dioxide, water, iron, coal and chromium (VI) to water are the main contributors to the overall environmental burden. The internal and external costs are $6433/metric ton and $370/metric ton, respectively. Analysis results indicate that the optimization of organic chemicals, recycled polyester filament and steam production processes can reduce environmental and economic burdens substantially. Energy substitutions with natural gas and the use of solar photovoltaic in steam production and electricity generation are effective measures for decreasing environmental impacts. Finally, suggestions based on research results and the current status of waste plastic bottle recycling in China are proposed.