Regulated and unregulated emissions from Euro VI Diesel and CNG heavy-duty vehicles.

This study compares emissions from Euro VI-D Diesel and CNG buses across temperatures from -7 °C to 35 °C. Pollutants including NOx, THC, CH4, CO, NH3, N2O, HCHO, Solid Particle Number larger than 23 nm (SPN23) and larger than 10 nm (SPN10) were measured. Both buses complied with Euro VI-D but exceeded European Commission's proposed Euro 7 limits, notably for NOx and SPN10. The CNG bus also surpassed NH3, CO, and CH4 limits, while the Diesel exceeded N2O limits. High NH3 emissions were observed from CNG (up to 0.320 g/kWh), with Diesel reporting lower levels (up to 0.021 g/kWh). HCHO emission from both vehicles were very low. SPN23 was under limits, but SPN10 exceeded Euro 7 limits at cold start tests. CNG's CH4 and N2O emissions constituted up to 4.6% and 3.5% of CO2 equivalent, respectively. Diesel bus showed negligible CH4 but N2O emissions represented up to 37% of CO2 equivalent.

Life cycle assessment of tomato biomass residue anaerobic digestion preceded by ethanol-based organosolv and choline chloride-based deep eutectic solvent.

Anaerobic digestion (AD) of lignocellulosic wastes (LW) has garnered substantial interest because of its notable energy and nutrient recovery, along with its potential for reducing greenhouse gas emissions. However, the LW is resistant to degradation, and its hydrolysis typically requires harsh conditions, hence the need for a pretreatment. Conducting a life cycle assessment (LCA) to evaluate the pretreatment of LW is an effective way to assess the environmental impacts associated with various pretreatment methods. This work evaluates and compares three scenarios for handling lignified tomato green waste (TGW), generated in the Greater of Agadir in Morocco, in terms of their environmental impacts and energy demand, using the LCA approach, performed with OpenLCA software. To achieve this aim, the impact of these scenarios on 11 indicators is studied. The analyzed management options include a base case scenario S0 where TGW undergoes a direct anaerobic digestion (AD), organosolv pretreatment of TGW followed by AD of the free-lignin fraction (S1), and choline chloride-based deep eutectic solvent (DES) delignification followed by AD of the free-lignin fraction (S2). The data used for the analysis comes from the Tamelast landfill, laboratory tests, literature, CML-IA baseline and Monte Carlo simulation calculations. The results obtained showed that the introduction of pretreatments in S1 and S2 mitigates significantly the environmental impact in different categories compared to S0. Scenario S2, with its enhanced recovery processes, shows the highest positive environmental contributions, despite its reliance on additional external electricity. S1 and S0 both respect energy circularity. Through this study, it has been demonstrated that chemical pretreatment of LW is energy, water and solvent-intensive and requires a large investment. It opens up perspectives for further works on pretreatment using natural DES technology, its development and its applications in the delignification of ligneous biomass on an industrial scale.

Enhancing energy and nitrogen removal efficiency through automatic split injection and innovative aeration device: A study of low C/N ratio environments.

A new aeration device based on Bernoulli's principle, Jetventrumixer (JVM), was introduced into an aeration tank in denitrification process, which involved an automatic split injection system (ASIS) into two denitrification tanks every 10 minutes. Real-time monitoring of influent water allowed the calculation of the C/N ratio, enhancing the utilization efficiency of internal carbon sources while reducing the need for external carbon. The comparison of the JVM with the conventional air diffuser for 100 days operation showed that the removal efficiency for NH4+-N in both systems was approximately 98 %, but the nitrification efficiencies were 84 % and 80 %, respectively. This indicates that the JVM achieves an high enough removal efficiency and nitrification efficiency compared with conventional air diffuser system with dramatic reduction in energy consumption by 52.1 %. When the influent wastewater was split and injected into duplicate denitrification tanks at ratios of 3:7, 5:5, and 7:3, the total nitrogen (TN) removal efficiencies were 77 %, 73 %, and 72 %, respectively. In contrast, with the implementation of the ASIS, the TN removal efficiency increased up to 82 %. The increase in TN removal indicates that real-time monitoring could stably track changes chemical composition in wastewater influent over 24 h and introducing ASIS facilitate the efficient utilization of internal carbon sources, thereby enhancing denitrification efficiency and improving TN removal efficiency. Finally, the greenhouse gas (GHG) emissions from the JVM and air diffuser were 9.39401 and 19.60488 tCO2eq year-1, respectively, representing a 52% reduction. Therefore, JVM and ASIS successfully reduced energy consumption and enhanced both nitrification and denitrification efficiencies.

Bayesian model of tilling wheat confronting climatic and sustainability challenges.

Conventional farming poses threats to sustainable agriculture in growing food demands and increasing flooding risks. This research introduces a Bayesian Belief Network (BBN) to address these concerns. The model explores tillage adaptation for flood management in soils with varying organic carbon (OC) contents for winter wheat production. Three real soils, emphasizing texture and soil water properties, were sourced from the NETMAP soilscape of the Pang catchment area in Berkshire, United Kingdom. Modified with OC content at four levels (1, 3, 5, 7%), they were modeled alongside relevant variables in a BBN. The Decision Support System for Agrotechnology Transfer (DSSAT) simulated datasets across 48 cropping seasons to parameterize the BBN. The study compared tillage effects on wheat yield, surface runoff, and GHG-CO2 emissions, categorizing model parameters (from lower to higher bands) based on statistical data distribution. Results revealed that NT outperformed CT in the highest parametric category, comparing probabilistic estimates with reduced GHG-CO2 emissions from "7.34 to 7.31%" and cumulative runoff from "8.52 to 8.50%," while yield increased from "7.46 to 7.56%." Conversely, CT exhibited increased emissions from "7.34 to 7.36%" and cumulative runoff from "8.52 to 8.55%," along with reduced yield from "7.46 to 7.35%." The BBN model effectively captured uncertainties, offering posterior probability distributions reflecting conditional relationships across variables and offered decision choice for NT favoring soil carbon stocks in winter wheat (highest among soils "NT.OC-7%PDPG8," e.g., 286,634 kg/ha) over CT (lowest in "CT.OC-3.9%PDPG8," e.g., 5,894 kg/ha). On average, NT released minimum GHG- CO2 emissions to "3,985 kgCO2eqv/ha," while CT emitted "7,415 kgCO2eqv/ha." Conversely, NT emitted "8,747 kgCO2eqv/ha" for maximum emissions, while CT emitted "15,356 kgCO2eqv/ha." NT resulted in lower surface runoff against CT in all soils and limits runoff generations naturally for flood alleviation with the potential for customized improvement. The study recommends the model for extensive assessments of various spatiotemporal conditions. The research findings align with sustainable development goals, e.g., SDG12 and SDG13 for responsible production and climate actions, respectively, as defined by the Agriculture and Food Organization of the United Nations.

Evaluation of greenhouse gas emission and reduction potential of high-food-waste-content municipal solid waste landfills: A case study of a landfill in the east of China.

This study proposes a comprehensive evaluation method based on a two-stage model to assess greenhouse gas (GHG) emissions and reductions in high-food-waste-content (HFWC) municipal solid waste (MSW) landfills. The proposed method considers typical processes such as fugitive landfill gas (LFG), LFG collection, flaring, power generation, and leachate treatment. A case study of an HFWC MSW landfill in eastern China is considered to illustrate the evaluation. The findings revealed that the GHG emissions equivalent of the case landfill amounted to 21.23 million tons from 2007 to 2022, averaging 1.03 tons CO2-eq per ton of MSW. There was a potential underestimation of LFG generation at the landfill site during the initial stages, which led to delayed LFG collection and substantial fugitive LFG emissions. Additionally, the time distribution of GHG emissions from HFWC MSW was significantly different from that of low-food-waste-content (LFWC) MSW landfills, with peak emissions occurring much earlier. Owing to the rapid degradation characteristics of HFWC MSW, the cumulative LFG production of the landfill by 2022 (2 years after the final cover) was projected to reach 77 % of the total LFG potential. In contrast, it would take until 2030 for LFWC MSW landfills to reach this level. Furthermore, various scenarios were analyzed, in which if the rapid LFG generation characteristics of HFWC MSW are known in advance, and relevant facilities are constructed ahead of time, the collection efficiency can be improved from 31 % to over 78 %, resulting in less GHG emissions.

Spatiotemporal patterns of greenhouse gas fluxes in the subtropical wetland ecosystem of Indian Himalayan foothill.

The study characterized the temporal and spatial variability in greenhouse gas (GHG) fluxes (CO2, CH4, and N2O) between December 2020 and November 2021 and their regulating drivers in the subtropical wetland of the Indian Himalayan foothill. Five distinct habitats (M1-sloppy surface at swamp forest, M2-plain surface at swamp forest, M3-swamp surface with small grasses, M4-marshy land with dense macrophytes, and M5-marshy land with sparse macrophytes) were studied. We conducted in situ measurements of GHG fluxes, microclimate (AT, ST, and SMC(v/v)), and soil properties (pH, EC, N, P, K, and SOC) in triplicates in all the habitat types. Across the habitats, CO2, CH4, and N2O fluxes ranged from 125 to 536 mg m-2 h-1, 0.32 to 28.4 mg m-2 h-1, and 0.16 to 3.14 mg m-2 h-1, respectively. The habitats (M3 and M5) exhibited higher GHG fluxes than the others. The CH4 flux followed the summer > autumn > spring > winter hierarchy. However, CO2 and N2O fluxes followed the summer > spring > autumn > winter. CO2 fluxes were primarily governed by ST and SOC. However, CH4 and N2O fluxes were mainly regulated by ST and SMC(v/v) across the habitats. In the case of N2O fluxes, soil P and EC also played a crucial role across the habitats. AT was a universal driver controlling all GHG fluxes across the habitats. The results emphasize that long-term GHG flux monitoring in sub-tropical Himalayan Wetlands has become imperative to accurately predict the near-future GHG fluxes and their changing nature with the ongoing climate change.

Spatial mapping of greenhouse gases using a UAV monitoring platform over a megacity in China.

Urban environments are recognized as main anthropogenic contributors to greenhouse gas (GHG) emissions, characterized by unevenly distributed emission sources over the urban environments. However, spatial GHG distributions in urban regions are typically obtained through monitoring at only a limited number of locations, or through model studies, which can lead to incomplete insights into the heterogeneity in the spatial distribution of GHGs. To address such information gap and to evaluate the spatial representation of a planned GHG monitoring network, a custom-developed atmospheric sampler was deployed on a UAV platform in this study to map the CO2 and CH4 mixing ratios in the atmosphere over Zhengzhou in central China, a megacity of nearly 13 million people. The aerial survey was conducted along the main roads at an altitude of 150 m above ground, covering a total distance of 170 km from the city center to the suburbs. The spatial distributions of CO2 and CH4 mixing ratios in Zhengzhou exhibited distinct heterogeneities, with average mixing ratios of CO2 and CH4 at 439.2 ± 10.8 ppm and 2.12 ± 0.04 ppm, respectively. A spatial autocorrelation analysis was performed on the measured GHG mixing ratios across the city, revealing a spatial correlation range of approximately 2 km for both CO2 and CH4 in the urban area. Such a spatial autocorrelation distance suggests that the urban GHG monitoring network designed for emission inversion purposes need to have a spatial resolution of 4 km to characterize the spatial heterogeneities in the GHGs. This UAV-based measurement approach demonstrates its capability to monitor GHG mixing ratios across urban landscapes, providing valuable insights for GHG monitoring network design.

Energy efficiency in medium-scale airports: Two Mexican airports as case of study.

Reducing energy consumption in the operation of airports has been identified as one of the approaches to achieve the commitments of the countries in reducing their greenhouse gas (GHG) emissions. The first step in this approach is the development of an energy diagnostic. However, multiple practical aspects remain unresolved when applying the existing methodologies to perform energy diagnostics, especially in the case of small and medium-scale airports. Seeking to address these issues, this work presents energy diagnostics of two Mexican international airports so that it can be used to carry out energy diagnostics in other airports with similar characteristics. Emphasis is given to identifying and prioritizing, from a sustainable point of view, the strategies to reduce energy consumption and GHG emissions. The Ciudad del Carmen Airport (CME) is located in a nearshore region with high ambient temperatures (27 °C) and humidities. It was found that in 2019, the CME airport consumed 123 MWh with an average of 577 Wh per passenger, with the HVAC system being the primary energy consumer. Critical strategies for the CME airport include photovoltaic systems and HVAC renovation. In contrast, the Puebla airport (PBC) is located in a region with comfortable ambient conditions (16 °C). In 2019, the PBC airport consumed 61.31 MWh/year and 442 Wh per passenger. The main strategies for PBC include expanding its photovoltaic energy generation system, employee awareness programs, and renewing the vehicle fleet with electric vehicles.

Climate change from the Asia-Pacific perspective: What an allergist needs to know and do.

Allergic diseases such as asthma, atopic dermatitis, and food allergies are a burgeoning health challenge in the Asia-Pacific region. Compounding this, the region has become increasingly susceptible to the impacts of climate change. The region has weathered extreme precipitation, intense heat waves, and dust storms over the recent decades. While the effects of environmental and genetic factors on allergic diseases are well understood, prevailing gaps in understanding the complex interactions between climate change and these factors remain. We aim to provide insights into the various pathways by which climate change influences allergic diseases in the Asia-Pacific population. We outline practical steps that allergists can take to reduce the carbon footprint of their practice on both a systemic and patient-specific level. We recommend that allergists optimize disease control to reduce the resources required for each patient's care, which contributes to reducing greenhouse gas emissions. We encourage the responsible prescription of metered dose inhalers by promoting the switch to dry powder inhalers for certain patients, at each clinician's discretion. We also recommend the utilization of virtual consultations to reduce patient travel while ensuring that evidence-based guidelines for rational allergy management are closely adhered to. Finally, eliminating unnecessary testing and medications will also reduce greenhouse gas emissions in many areas of medical care.

Atmospheric chemistry of CF3CHFCF2OCH3 (HFE-356mec3) and CHF2CHFOCF3 (HFE-236ea1) initiated by OH and Cl and their contribution to global warming.

The kinetic study of the gas-phase reactions of hydroxyl (OH) radicals and chlorine (Cl) atoms with CF3CHFCF2OCH3 (HFE-356mec3) and CHF2CHFOCF3 (HFE-236ea1) was performed by the pulsed laser photolysis/laser-induced fluorescence technique and a relative method by using Fourier Transform infrared (FTIR) spectroscopy as detection technique. The temperature dependences of the OH-rate coefficients (kOH(T) in cm3s-1) between 263 and 353 K are well described by the following expressions: 9.93 × 10-13exp{-(988 ± 35)/T}for HFE-356mec3 and 4.75 × 10-13exp{-(1285 ± 22)/T} for HFE-236ea1. Under NOx-free conditions, the rate coefficients kCl at 298 K and 1013 mbar (760 Torr) of air were determined to be (2.30 ± 1.08) × 10-13 cm3s-1and (1.19 ± 0.10) × 10-15 cm3s-1, for HFE-356mec3 and HFE-236ea1, respectively. Additionally, the relative kinetic study of the Cl + CH2ClCHCl2 reaction was investigated at 298 K, as it was used as a reference reaction in the kinetic study of the Cl-reaction with HFE-356mec3 and discrepant rate coefficients were found in the literature. The global atmospheric lifetimes were estimated relative to CH3CCl3 at the tropospheric mean temperature (272 K) as 1.4 and 8.6 years for HFE-356mec3 and HFE-236ea1, respectively. These values combined with the radiative efficiencies for HFE-356mec3 and HFE-236ea1 derived from the measured IR absorption cross sections (0.27 and 0.41 W m-2 ppv-1) yield global warming potentials at a 100-yrs time horizon of 143 and 1473, respectively. The contribution of HFE-356mec3 and HFE-236ea1 to global warming of the atmosphere would be large if they become widespread increasing their atmospheric concentration.

GHG emission quantification and reduction pathway of subway shield tunnel engineering: a case study on Guangzhou Metro, China.

The shield method is a commonly used construction technique in subway tunnel engineering. However, studies on greenhouse gas (GHG) emissions specifically in subway shield tunnel engineering are lacking. This study aims to investigate the GHG emission characteristics and GHG reduction pathways during the construction period of subway shield tunnels. Firstly, based on the life cycle assessment (LCA) method, a greenhouse gas (GHG) emission quantification model for the shield tunnel construction period was developed using a multi-level decomposition of construction. Then, the GHG emission level and intensity during the construction period of a case project are quantified, and its emission characteristics and GHG reduction potential points are assessed. Finally, a comprehensive path for GHG reduction in subway shield tunnel engineering is proposed. The research results indicate that constructing 1 km of subway shield tunnel can generate 19,294.28 t CO2eq. Among these, material production element dominates the emissions with a percentage of 89.05%, while transportation and mechanical construction elements contribute 1.81% and 9.14%, respectively. From the structure perspective, the main structure contributes 88.73% of total emissions, while the ancillary structure contributes 11.27%. Among them, the working shaft and tunnel segments are the main sources of emissions for the main structure, accounting for 23.65% and 65.08%, respectively. Connecting channel and end reinforcement are the main emission sources of the ancillary structures, accounting for 43.63% and 31.30%, respectively. These findings provide a scientific foundation for the environmentally friendly transformation of urban railway development regarding pursuing "carbon peaking and carbon neutrality" strategic goals.

Carbon footprint analysis of wastewater treatment processes coupled with sludge in situ reduction.

The goal of this study was to assess the impacts or benefits of sludge in situ reduction (SIR) within wastewater treatment processes with relation to global warming potential in wastewater treatment plants, with a comprehensive consideration of wastewater and sludge treatment. The anaerobic side-stream reactor (ASSR) and the sludge process reduction activated sludge (SPRAS), two typical SIR technologies, were used to compare the carbon footprint analysis results with the conventional anaerobic - anoxic - oxic (AAO) process. Compared to the AAO, the ASSR with a typical sludge reduction efficiency (SRE) of 30 % increased greenhouse gas (GHG) emissions by 1.1 - 1.7 %, while the SPRAS with a SRE of 74 % reduced GHG emissions by 12.3 - 17.6 %. Electricity consumption (0.025 - 0.027 kg CO2-eq/m3), CO2 emissions (0.016 - 0.059 kg CO2-eq/m3), and N2O emissions (0.009 - 0.023 kg CO2-eq/m3) for the removal of secondary substrates released from sludge decay in the SIR processes were the major contributor to the increased GHG emissions from the wastewater treatment system. By lowering sludge production and the organic matter content in the sludge, the SIR processes significantly decreased the carbon footprints associated with sludge treatment and disposal. The threshold SREs of the ASSR for GHG reduction were 27.7 % and 34.6 % for the advanced dewatering - sanitary landfill and conventional dewatering - drying-incinerating routes, respectively. Overall, the SPRAS process could be considered as a cost-effective and sustainable low-carbon SIR technology for wastewater treatment.

Influence of mandatory waste classification on environmental and economic impacts of residual waste treatment in Xiamen, China.

Mandatory waste classification has been widely considered as an effective solution for reducing the production and treatment amount of municipal solid waste. However, there is limited evidence regarding whether and how waste classification can affect the composition of residual waste (RW) and its environmental economic impacts. Here, an accounting method recommended by the Intergovernmental Panel on Climate Change, field surveys and cost-benefit analysis was utilized to investigate the changes in RW composition, environmental impacts and economic benefits under the waste classification policies implementation in Xiamen, China. This study found that: (1) The implementation of waste classification policies led to a significant increase in recyclable content from 17% to 51% and a decrease in organic content from 56% to 32%. (2) Waste classification effectively reduces greenhouse gas emissions from landfilling and incineration by an additional 0.34 tCO2-eq t-1 RW. (3) The introduction of mechanical recycling achieves a saving of 0.47 tCO2-eq t-1 RW at 40% recycling efficiency, a 4.5-fold increase compared to business as usual (BAU). (4) The operational benefits (900 yuan t-1 RW) from the recyclables sorting system offset the total expenses of investment, operation and waste disposal. The study successfully demonstrated that RW source-classified management can optimize the structure of waste composition, reduce environmental emissions and offer detailed guidance for the development of solid waste management systems in other cities in China.

Integrated catalytic systems for simultaneous NOx and PM reduction: a comprehensive evaluation of synergistic performance and combustion waste energy utilization.

The global transition towards sustainable automotive vehicles has driven the demand for energy-efficient internal combustion engines with advanced aftertreatment systems capable of reducing nitrogen oxides (NOx) and particulate matter (PM) emissions. This comprehensive review explores the latest advancements in aftertreatment technologies, focusing on the synergistic integration of in-cylinder combustion strategies, such as low-temperature combustion (LTC), with post-combustion purification systems. Selective catalytic reduction (SCR), lean NOx traps (LNT), and diesel particulate filters (DPF) are critically examined, highlighting novel catalyst formulations and system configurations that enhance low-temperature performance and durability. The review also investigates the potential of energy conversion and recovery techniques, including thermoelectric generators and organic Rankine cycles, to harness waste heat from the exhaust and improve overall system efficiency. By analyzing the complex interactions between engine operating parameters, combustion kinetics, and emission formation, this study provides valuable insights into the optimization of integrated LTC-aftertreatment systems. Furthermore, the review emphasizes the importance of considering real-world driving conditions and transient operation in the development and evaluation of these technologies. The findings presented in this article lay the foundation for future research efforts aimed at overcoming the limitations of current aftertreatment systems and achieving superior emission reduction performance in advanced combustion engines, ultimately contributing to the development of sustainable and efficient automotive technologies.

The carbon footprint of health care delivery in Western Australia's public health system.

Background: Health systems have a dual imperative to take action on climate change. First, they must develop climate resilient health services in response to the direct and indirect impacts of climate change on health. Second, they must reduce their own carbon footprint since health systems are a significant contributor to global greenhouse gas emissions. Methods: An environmentally-extended multi-region input-output analysis was carried out, incorporating National Accounts data for Australia and annual expenditure data from WA Health for financial year 2019-20. Expenditure data were categorised to one of 344 economic sectors and by location of the provider of goods or services purchased. Findings: WA Health contributes 8% of WA's total carbon footprint, driven by expenditure on chemicals (23.8% of total), transport (20.2% of total), and electricity supply (19.7% of total). These 3 sectors represent 63.7% of WA Health's carbon footprint, but only 10.8% of its total expenditure. Interpretation: Reducing emissions related to health service provision in WA will require a holistic approach that leverages carbon footprinting insights and integrates them into organisational decision-making across all health programs. The high carbon-intensity of the transport and chemicals sectors supports previous research calling for a reduction in unnecessary pathology testing and the transition to delivery of non-urgent health care via sustainable models of telehealth. The impact of WA's size and location presents challenges, with a predominantly non-renewable energy supply and reliance on transport and supply chains from other states adding significantly to emissions. Funding: The study received funding from the Australian Research Council, The University of Sydney, and the WA Department of Health. The full list of funding information can be found in Acknowledgements.

Urbanization and greenhouse gas emissions from municipal wastewater in coastal provinces of China: Spatiotemporal patterns, driving factors, and mitigation strategies.

Coastal cities, as hubs of social and economic activity, have witnessed rapid urbanization and population growth. This study explores the transformative changes in urban municipal wastewater treatment practices and their profound implications for greenhouse gas (GHG) emissions in Chinese coastal provinces. The approach employed in this study integrates comprehensive data analysis with statistical modeling to elucidate the complex interplay between urbanization, wastewater treatment practices, and GHG emissions. Results reveal a substantial surge in GHG emissions from coastal wastewater treatment, rising from 3367.1 Gg CO2e/yr in 1990-23644.8 Gg CO2e/yr in 2019. Spatially, the top 20 cities contribute 56.0% of emissions, with hotspots in the Bohai Sea Region, Yangtze River Delta, and Pearl River Delta. Initially dominated by emissions from untreated wastewater, post-2004, GHG emissions from treatment processes became the primary source, tied to electricity use. Growing population and urbanization rates escalated wastewater discharge, intensifying GHG emissions. From 1990 to 2019, average GHG intensity ranged between 320.5 and 676.6 g CO2e/m3 wastewater, with an annual increase of 12.3 g CO2e/m3. GHG intensity variations relate to the wastewater treatment rate, impacting CH4, N2O, and CO2 emissions, underscoring the need for targeted strategies to mitigate environmental impact.

Estimating carbon and water footprints associated with commercial milk formula production and use: development and implications of the Green Feeding Climate Action Tool.

Carbon offset frameworks like the UN Clean Development Mechanism (CDM) have largely overlooked interventions involving food, health, and care systems, including breastfeeding. The innovative Green Feeding Climate Action Tool (GFT) assesses the environmental impact of commercial milk formula (CMF) use, and advocates for breastfeeding support interventions as legitimate carbon offsets. This paper provides an overview of the GFT's development, key features, and potential uses. The offline and online GFT were developed using the DMADV methodology (Define, Measure, Analyze, Design, Verify). The GFT reveals that the production and use of CMF by infants under 6 months results in annual global greenhouse gas (GHG) emissions of between 5.9 and 7.5 billion kg CO2 eq. and consumes 2,562.5 billion liters of water. As a national example, in India, one of the world's most populous countries, CMF consumption requires 250.6 billion liters of water and results in GHG emissions ranging from 579 to 737 million kg CO2 eq. annually, despite the country's high breastfeeding prevalence among infants under 6 months. The GFT mainly draws on data for low- and middle-income countries (LMICs), as many high-income countries (HICs) do not collect suitable data for such calculations. Despite poor official data on breastfeeding practices in HICs, GFT users can input their own data from smaller-scale surveys or their best estimates. The GFT also offers the capability to estimate and compare baseline with counterfactual scenarios, such as for interventions or policy changes that improve breastfeeding practices. In conclusion, the GFT is an important innovation to quantify CMF's environmental impact and highlight the significance of breastfeeding for planetary as well as human health. Women's contributions to environmental preservation through breastfeeding should be recognized, and breastfeeding interventions and policies should be funded as legitimate carbon offsets. The GFT quantifies CMF's carbon and water footprints and facilitates financing breastfeeding support as a carbon offset initiative under CDM funding facilities.

Techno-economic evaluation of GHG emissions mitigation of biomethane upgrading technologies.

The current trend in the European biogas industry is to shift away from electricity production towards the production of biomethane for the need to replace natural gas. The upgrading of biogas to biomethane is normally performed by separating the biogas in a stream containing natural gas grid quality methane and a stream containing mostly CO2. The CO2 stream is normally released into the atmosphere; however, part of the methane may still remain in it, and, if not oxidized, even a small fraction of methane released may jeopardise all the GHG emissions savings from producing the biomethane, being methane a powerful climate forcer. Scope of this work is to assess the opportunity cost of installing an Off Gas Combustion (OGC) device in biomethane upgrading plants. The currently available technologies for biogas upgrading to biomethane and the most common technology of OGC (the Regenerative Thermal Oxidisers, RTO) are described according to their performances and cost. Then the cost per tonne of CO2eq avoided associated to the adoption of RTO systems in relation to the upgrading performance is calculated to identify a potential threshold for an effective and efficient application of the RTO systems. It is found that, in case of upgrading technologies which can capture almost all biomethane in the upgrading off-gas (i.e. 99.9%), currently the adoption of an RTO to oxidise the methane left in the off-gas would add costs and need additional fuel to be operated, but would generate limited GHG emission savings, therefore the cost per tonne of CO2eq emissions avoided would result not competitive with other GHG emissions mitigation investments. While the installation of RTOs on upgrading systems with a methane slip of 0.3%, or higher, normally results cost competitive in reducing GHG emissions. The installation of an RTO on systems with a methane slip of 0.2% results in a cost per tonne of CO2eq emissions avoided of 50-100 euro, which is comparable to the current cost of CO2 emissions allowances in the EU ETS carbon market, representing therefore a reasonable choice for a threshold on methane slip regulation for biogas upgrading systems.

Life cycle GHG emissions assessment of vanadium recovery from bitumen-derived petcoke fly ash.

Petcoke generated during bitumen upgrading is a potential source of vanadium for the global market. Recovering vanadium from the fly ash originating from the combustion of petcoke appears to be a suitable route for commercial implementation, given its high extraction rate. Although the technical feasibility of the recovery process has been proven, the environmental impact should be addressed. Information on the greenhouse (GHG) emissions from the process is scarce in the public domain. Therefore, a framework was developed for assessment of life cycle GHG emissions for extraction of vanadium from petcoke-based fly ash. This framework was used to perform a life cycle GHG emissions assessment of a water leaching and salt roasting process to extract vanadium from fly ash. For the upstream GHG emissions, we collected direct emissions data and energy consumption from the literature, and, for the process emissions, we developed a model to estimate energy and material balances based on process conditions. The emission factors for electricity production, fuel combustion, production of consumables, and gas treatment were used to obtain the life cycle GHG emissions. The results show that the life cycle GHG emission of vanadium recovery are 26.6-3.9+0.9 kg CO2eq/kg V2O5; 66% of these are direct GHG emissions. The process GHG emissions from fly ash decarbonization contribute the most to the life cycle GHG emissions. The air-to-fuel ratio for roasting and the GHG emission factors for petcoke combustion and the gas treatment operation are the inputs that most effect the model output. Compared with the production of V2O5 from vanadium titano-magnetite ore and bitumen upgrading spent catalyst, the petcoke fly ash pathway generates about twice the life cycle GHG emissions. This study's results can help determine areas of improvement in the upstream operations and the recovery process to reduce the life cycle GHG emissions to levels that can compete with primary and alternative routes to produce vanadium pentoxide. The results of this study can help in decision-making associated with vanadium extract from fly ash produced from combustion of petcoke.

A Comprehensive Approach for Designing Low Carbon Wood Bio-Concretes.

This paper presents a method for designing low carbon bio-based building materials, also named bio-concretes, produced with wood wastes in shavings form (WS) and cementitious pastes. As the aggregates phase of bio-concretes is composed of plant-based particles, known as porous and high water-absorbing materials, the bio-concretes cannot be designed by using the traditional design rules used for conventional mortar or concrete. Then, the method used in the current paper is an adaptation of a previous one that has been developed in a recent paper where bio-concretes were produced with a cement matrix, three types of bio-aggregates, and a proposal of a design abacus. However, when that abacus is used for designing WBC with low cement content in the matrix, the target compressive strength is not reached. In the present paper, the method is extended to low cement content matrix (up to 70% of cement substitution) and also considering the greenhouse gas (GHG) emission of the WBC. To obtain data for proposing a new design abacus, an experimental program was carried out by producing nine workable WBCs, varying wood volumetric fractions (40-45-50%), and water-to-binder ratios. The bio-concretes produced presented adequate consistency, lightness (density between 715 and 1207 kg/m3), and compressive strength ranging from 0.64 to 12.27 MPa. In addition, the GHG emissions of the WBC were analysed through the Life Cycle Assessment methodology. From the relationships obtained between density, compressive strength, water-to-binder ratio, cement consumption, and GHG emissions of the WBC, calibration constants were proposed for developing the updated and more complete abacus regarding an integrated mix design methodology.