Total Greenhouse Gas Emissions Research Articles

The impact of refrigeration on food losses and associated greenhouse gas emissions throughout the supply chain

One-third of food produced globally is wasted while approximately 800 million people suffer from hunger. Meanwhile, food losses produce approximately 8% of total anthropogenic greenhouse gas (GHG) emissions. This study develops a food loss estimation tool to assess how improved access to the cold chain could impact food loss and its associated GHG emissions for seven food types in seven regions. This study estimates that poor cold chain infrastructure could be responsible for up to 620 million metric tons (Mmt) of food loss, responsible for 1.8 GtCO2-eq annually. Utilizing fully optimized cold chains could save over 100 Mmt of fruit and vegetable loss in South & Southeast Asia and over 700 Mmt CO2-eq in Sub-Saharan Africa. Developing more localized, less industrialized (‘farm-to-table’) food supply chains in both industrialized and non-industrialized contexts may save greater quantities of food than optimized cold chains. Utilizing localized supply chains could save over 250 Mmt of roots and tubers globally (over 100 Mmt more savings than those of an optimized cold chain) and reduce GHG emissions from meat losses in industrialized regions by over 300 Mmt CO2-eq. Due to the differences in the environmental intensity of food types, cold chain investments that prioritize reducing overall food losses will have very different outcomes than those that prioritize reducing GHG emissions.

Investigating the Nexus Between GHG Emissions and AFOLU Activities: New Insights from C-Vine Copula Approach

The greenhouse gas (GHG) emissions from agriculture, forestry, and other land use (AFOLU) account for more than 10% of the total GHG emissions in Iran. To reduce the environmental impact, assessments of Iran’s GHG emissions status are critical for identifying the national policies to achieve Sustainable Development Goals (SDGs) in the bio-based industry. However, there is no study exploring the dependency between AFOLU and GHG emissions in Iran by using the Vine Copula approach. Hence, the study aims to examine the causality direction and correlation structure among selected horticulture, farming crops, livestock, and poultry products and carbon dioxide (CO2), nitrogen dioxide (N2O), and methane emissions (CH4) in the Iranian agriculture sector over the period 1961–2019, to determine which crops or products are more responsible to deteriorate the environment. The empirical strategy used a C-Vine Copula model to measure the correlations together with the Granger causality (GC) test to analyze the causality links. According to the empirical findings, several crops and products are the sources of emissions. Rice and vegetable cultivations, as well as meat and milk products (Kendall’s τ values of 0.37, 0.33, 0.31, and 0.31, respectively), are the leading sources of CH4 emissions. Legumes, eggs, maize, rice, and milk enhance N2O emissions, while CO2 emissions are caused by apple, potato, and apricot crops (Kendall’s τ values of 0.22, 0.18, and 0.16, respectively). Finally, based on the findings, policy implications are offered.

Quantification of the environmental impact of radiotherapy and associated secondary human health effects: a multi-institutional retrospective analysis and simulation

The health-care industry is a substantial contributor to global greenhouse gas emissions, yet the specific environmental impact of radiotherapy, a cornerstone of cancer treatment, remains under-explored. We aimed to quantify the emissions associated with the delivery of radiotherapy in the USA and propose a framework for reducing the environmental impact of oncology care. In this multi-institutional retrospective analysis and simulation study, we conducted a lifecycle assessment of external beam radiotherapy (EBRT) for ten anatomical disease sites, adhering to the International Organization for Standardization's standards ISO 14040 and ISO 14044. We analysed retrospective data from Jan 1, 2017, to Oct 1, 2023, encompassing patient and staff travel, medical supplies, and equipment and building energy use associated with the use of EBRT at four academic institutions in the USA. The primary objective was to measure the environmental impacts across ten categories: greenhouse gases (expressed as kg of carbon dioxide equivalents [CO2e]), ozone depletion, smog formation, acidification, eutrophication, carcinogenic and non-carcinogenic potential, respiratory effects, fossil fuel depletion, and ecotoxicity. Human health effects secondary to these environmental impacts were also estimated as disability-adjusted life years. We also assessed the potential benefits of hypofractionated regimens for breast and genitourinary (ie, prostate and bladder) cancers on US greenhouse gas emissions using an analytic model based on the 2014 US National Cancer Database for fractionation patterns and patient commute distances. We estimated that the mean greenhouse gas emissions associated with a standard 25-fraction EBRT course were 4310 kg CO2e (SD 2910), which corresponded to 0·0035 disability-adjusted life years per treatment course. Transit and building energy usage accounted for 25·73% (1110 kg CO2e) and 73·95% of (3190 kg CO2e) of total greenhouse gas emissions, respectively, whereas supplies contributed only 0·32% (14 kg CO2e). Across the other environmental impact categories, most of the environmental impact also stemmed from patient transit and energy use within facilities, with little environmental impact contributed by supplies used. Hypofractionated treatment simulations suggested a substantial reduction in greenhouse gas emissions-by up to 42% for breast and 77% for genitourinary cancer-and environmental impacts more broadly. This comprehensive lifecycle assessment of EBRT delineates the environmental and secondary health impacts of radiotherapy, and underscores the urgent need for sustainable practices in oncology. The findings serve as a reference for future decarbonisation efforts in cancer care and show the potential environmental benefits of modifying treatment protocols (when clinical equipoise exists). They also highlight strategic opportunities to mitigate the ecological footprint in an era of escalating climate change and increasing cancer prevalence. Mount Zion Health Fund.

Trends in the contribution of greenhouse gas emissions from food and beverage purchases in Mexico: 1989–2020

BackgroundAssessing the trends in dietary GHGE considering the social patterning is critical for understanding the role that food systems have played and will play in global emissions in countries of the global south. Our aim is to describe dietary greenhouse gas emissions (GHGE) trends (overall and by food group) using data from household food purchase surveys from 1989 to 2020 in Mexico, overall and by education levels and urbanicity.MethodsWe used cross-sectional data from 16 rounds of Mexico’s National Income and Expenditure Survey, a nationally representative survey. The sample size ranged from 11,051 in 1989 to 88,398 in 2020. We estimated the mean total GHGE per adult-equivalent per day (kg CO2-eq/ad-eq/d) for every survey year. Then, we estimated the relative GHGE contribution by food group for each household. These same analyses were conducted stratifying by education and urbanicity.ResultsThe mean total GHGE increased from 3.70 (95%CI: 3.57, 3.82) to 4.90 (95% CI 4.62, 5.18) kg CO2-eq/ad-eq/d between 1989 and 2014 and stayed stable between 4.63 (95% CI: 4.53, 4.72) and 4.89 (95% CI: 4.81, 4.96) kg CO2-eq/ad-eq/d from 2016 onwards. In 1989, beef (19.89%, 95% CI: 19.18, 20.59), dairy (16.87%, 95% CI: 16.30, 17.42)), corn (9.61%, 95% CI: 9.00, 10.22), legumes (7.03%, 95% CI: 6.59, 7.46), and beverages (6.99%, 95% CI: 6.66, 7.32) had the highest relative contribution to food GHGE; by 2020, beef was the top contributor (17.68%, 95%CI: 17.46, 17.89) followed by fast food (14.17%, 95% CI: 13.90, 14.43), dairy (11.21%, 95%CI: 11.06, 11.36), beverages (10.09%, 95%CI: 9.94, 10.23), and chicken (10.04%, 95%CI: 9.90, 10.17). Households with higher education levels and those in more urbanized areas contributed more to dietary GHGE across the full period. However, households with lower education levels and those in rural areas had the highest increase in these emissions from 1989 to 2020.ConclusionsOur results provide insights into the food groups in which the 2023 Mexican Dietary Guidelines may require to focus on improving human and planetary health.

Assessing the effectiveness of building retrofits in reducing GHG emissions: A Canadian school case study

This paper investigates the impact of energy retrofits on life cycle greenhouse gas (GHG) emissions across different electricity grid profiles in Montreal, Ottawa, and Halifax, using an existing school building as a case study. Using DesignBuilder for energy simulations and OneClick LCA for GHG emissions estimation, this study evaluates whether the reduction in the operational emission achieved by energy savings from retrofits can outweigh the increased embodied emissions from new envelope materials and equipment. In Montreal and Ottawa, where electricity is mainly generated from renewables and non-fossil fuels, retrofits involving electric heating and envelope improvements could decrease life cycle GHG emissions by up to 75 %. However, if the building initially used electric heating, the retrofits led to an increase in life cycle carbon emissions by 170 % in Montreal and 56 % in Ottawa, respectively, due to the embodied emissions of retrofit materials and equipment. In Halifax, where the electricity grid relies heavily on fossil fuels, all retrofit scenarios showed a positive impact on GHG reductions. Enhancing the building envelope and transitioning from natural gas to electric heating slightly reduced total emissions by 4 %, but retaining natural gas heating decreased the total life cycle GHG emissions by 27 %. This study emphasizes the importance of a comprehensive life cycle assessment in developing policies for achieving carbon neutrality. It demonstrates that the effectiveness of retrofits in reducing GHG emissions significantly depends on the local energy grid, suggesting tailored approaches based on regional energy profiles to optimize emission reductions and energy efficiency.

Reducing energy and carbon footprint through diversified rainfed cropping systems

Agriculture is the second largest contributor (20 %) to total anthropogenic greenhouse gas (GHG) emissions in the world. There is a need to identify energy and carbon efficient cropping systems that reduce GHG emission and improve environmental quality. Using life cycle assessment (LCA), we evaluated the four cropping systems namely fallow – chickpea (F–C); Sesbania – mustard (Ses–M); blackgram – chickpea (B–C); sorghum + cowpea – mustard (S + C–M) cultivated during the 2018–2022 period. The energy use pattern and the input-output relationship were analysed. Three measures were utilized to quantify carbon footprints: CFa, which denotes emissions per unit area; CFb, indicating emissions per kilogram of yield; and CFe, representing emissions per unit of economic output. The result indicates that non-renewable sources of energy (diesel and fertilizer) contributed more than ∼80 % of the total energy consumed in the different cropping systems. The total energy requirement was the highest for S + C–M (16,972 MJ ha–1), followed by Ses–M (14,365 MJ ha–1), B–C (11,132 MJ ha–1) and F–C (8679 MJ ha–1) cropping systems. The S + C–M cropping system also had the highest energy use efficiency (9.13) followed by F–C (6.03), B–C (5.41) and Ses–M (5.41). The fallow–chickpea cropping system had the lowest values of CFa, CFb, and CFe however, the highest carbon efficiency (10.7) and the carbon sustainability index (9.7) were computed in S + C–M cropping system. Our findings indicate that thoughtfully structured, varied crop systems that integrate legumes and forage crops have the potential to significantly reduce energy consumption and carbon emissions, while sustaining or potentially improving overall productivity within these systems.

Greenhouse gas reduction in a medium-duty compression ignition engine with optimization for B20

Soy-based biodiesel can reduce well-to-wheels greenhouse gas (GHG) emissions per unit energy (i.e., gCO2e/MJ) by 66%–72% as compared to the petroleum-based diesel fuel with currently adopted agricultural and industrial practices. Biodiesel can reduce particulate matter and carbon monoxide emissions with a manageable degree of increase in NOx emissions. From the perspective of GHG emissions reduction per unit travelling distance (i.e., gCO2e/mile), the application of B20 in compression ignition engines without the adjustment in engine control unit (ECU) settings will not extract the best carbon emissions reduction that B20 could achieve. Optimizing the engine control settings permits re-calibration to achieve the maximum brake fuel conversion efficiency (BFE) based on comprehensive understanding on the impact of both “fuel” and “ECU calibration” on BFE and other criteria pollutant emissions. The maximum GHG emissions reduction with B20 application is experimentally measured with the optimized ECU calibration, thus providing the understanding of the combined impact of biodiesel fuel and calibrations on engine performance and emissions. Six steady operating modes were considered, that can be combined to estimate the US federal test procedure BFE and emissions over the Federal Test Protocol (FTP) 75 cycle. Combined with the weight factors to simulate the EPA FTP 75 cycle from these 6 “mini-map” test points, 0.53% improvement in the energy requirement per unit traveling distance (i.e., MJ/mile) is achieved for B20 with the final ECU calibration, in addition to the degree of GHG emissions reduction on a “gCO2e/MJ” basis from the use of B20 blend of soy biodiesel of ∼12.5% reduction in gCO2e/MJ, for a total GHG emissions reduction of 13%.

Living emission abolish filters (LEAFs) for methane mitigation: design and operation

As one of the most potent greenhouse gases, methane is a critical target for the near-term mitigation of global warming. Efficient, scalable, easy-to-implement, and robust mitigation technologies are urgently needed to assist in reaching methane abolishment. The goal of this research was to test the applicability of active, extremophilic methanotrophic cells as a baseline concept for engineered systems aiming at methane capturing. The system, named living emission abolish filters (LEAFs), represents an array of immobilized biomaterials capable of capturing methane directly from vent streams. The biomaterials were made using cells of Methylotuvimicrobium alcaliphilum 20ZR, a robust halophilic methanotrophic bacterium with the ability to consume methane gas at low concentrations. Several critical parameters were tested, including (i) the composition of the matrix and optimal immobilization to increase catalyst load, (ii) the stability of methanotrophic cells, and (iii) the toxicity of trace gases (i.e. CO). We found that hydrogels coated with 2.3 mg cell dry weight/cm3 methanotrophic cells represent the best-performing biomaterials. The methane reduction potential of LEAFs fluctuated from 20% to 95% and depended on the methane concentration in the gas stream and the stream flow rates. The potential for commercial-scale deployment and emissions reductions was also evaluated. Total greenhouse gas emissions (combined using the global warming potential GWP100) from an example using a ventilation air methane source over a one-year period was shown to be reduced in two LEAF scenarios by 51% and 75%. Over longer time horizons, more significant reductions are possible as consistent methane consumption can be sustained. The study highlights the overall potential of the liquid-free bio-based composite methane mitigation system. Further improvements essential for system assembly and implementations should include (a) optimization of the cell immobilization protocols to improve cell load and the shelf-life of the system and (b) implementation of matrix moldings for cell immobilization to achieve optimal gas flow and increase the cell-gas interface.

Potential for low-emissions oil palm production in Indonesia: insights from spatiotemporal dynamics

Rising global demand for palm oil has created environmental pressures related to deforestation, burning, and peat exploitation, which in turn drives increased greenhouse gas (GHG) emissions. GHG emissions in oil palm (OP) production are known to vary spatially. However, temporal changes across contrasting management and soil types, are less well studied. This paper quantifies spatiotemporal GHG emissions across contrasting regions, management types, and soil types for the period 1990–2019 to assess the potential for reducing emission. The study focusses on Indonesia, as the biggest producer of OP, and in particular on the North Sumatra and Riau provinces, where OP is intensively produced. GHG inventories in 5 year time steps were constructed to investigate the change in drivers of emissions using spatial data, resampled to a 500 m grid. Total GHG emissions were found to have increased in both regions due to expanding OP production. However, results show a reduction in emissions flux from 1.98 to 1.15 Ton Ceq. ha−1yr−1 in North Sumatra and 9.63–2.67 Ton Ceq. ha−1yr−1 in Riau over the study period. This reduced flux was linked to the decreased deforestation and burning activities, together with increased biomass increment from lower carbon stock area conversion to OP. In both provinces, smallholder plantations emitted fewer emissions than industrial ones, and production on organic soils resulted in consistently higher emissions than on mineral soils. In North Sumatra, emissions under all management and soil types were found to decrease. In Riau, however, GHG emissions on organic soils regardless of management types, remained high. Our findings emphasise that potential for low-emissions OP production is attainable by reducing emissions per unit area through an improved understanding of GHG emissions spatiotemporal variability and their drivers. These contribute to reinforcing ongoing government regulations and guiding the industry towards low-emission OP productions.

Enhancing sustainable ethanol fuel production from cassava in Vietnam

This study focused on developing a comprehensive model to perform techno-economic analysis and calculate greenhouse gas emissions and net energy balance of cassava-based ethanol production in Vietnam. Four steps were involved in this study: (1) collecting data on the cassava-based ethanol conversion pathway, (2) modeling an ethanol production plant, (3) calculating greenhouse gas emissions and net energy balance, and (4) evaluating economic feasibility. The total capital investment and production cost per liter of ethanol are 0.6 $/l/yr and 0.4 $/l, respectively. The fossil energy consumption and net energy ratio during cultivation, transportation, production, and use of ethanol are 12.4 MJ/l and 1.70, respectively. The total greenhouse gas emissions of cassava-based ethanol production are 1252 gCO2eq/l or 59.1 gCO2eq/MJ, which equals 63 % of greenhouse gas emissions from gasoline. This finding confirms that cassava-based ethanol can be an alternative fuel based on economic feasibility and environmental benefit by reducing greenhouse gas emissions in Vietnam.

Causal relationship between household consumption transition and CO2 emission in China: a dynamic panel model.

The mitigation of carbon dioxide (CO2) generated from household consumption, accounting for 52% of China's total greenhouse gas emissions, plays a pivotal role in China's pursuit of reaching a carbon peak by 2030. The study used three waves of nationally representative longitudinal data, energy statistics data, and input-output table to estimate household CO2 emissions (HCEs) in China at the micro-scale. The dynamic relationship between household consumption pattern transition and HCEs per capita was explored by applying maximum likelihood and structural equation modeling (ML-SEM) with panel data. The results indicate that per capita HCE level in a given year appears to be positively associated with HCE level for the same household in the previous year. A U-shaped relationship between consumption pattern transition and HCEs per capita was confirmed, as well as the reinforcement effect of income on the impacts of consumption pattern transition. The increase in consumption propensity, household income, share of wage-income, household asset values, and house space results in higher HCEs per capita. The family size and dependency ratio have a negative relationship with HCEs, whereas households that are female-oriented and more Internet-dependent tend to produce more CO2. Exploring the consumption transition of households is crucial for reducing CO2 emissions at the household level in China.

Energy Utilization and Greenhouse Gas (GHG) Emissions of Tillage Operation in Wetland Rice Cultivation

In Malaysia, wetland rice is cultivated over two cropping seasons: the main season, from June to November, and the off-season, from January to June. The aim of this study was to investigate tillage operations in rice production in relation to actual field operations and under real field conditions for two rice cultivation seasons. The results showed that 80.7%, 17%, and 2.3% of the total time was spent on the actual operation, turning time, and reversing time, respectively. The results also showed that the mean effective field capacity, field efficiency, and fuel consumption were 1.2 ha/h, 80%, and 7.6 L/ha, respectively. The distribution of energy used in the first, second, and third tillage passes amounted to 37%, 33%, and 30% of the total energy, respectively. Fuel, machinery, and total GHG emissions were 62.4, 7.6, and 70 kg CO2eq/ha, respectively. Fuel represented the highest contributor of energy expenditure and GHG emissions. The distributions of GHG emissions in the first, second, and third tillage passes were 37%, 32%, and 31% of the total GHG emissions. The results reveal that carrying out minimum-tillage operations led to a reduction in environmental impacts.

The Effects of Local Food on Carbon Emissions: The Case of the Republic of Korea

This study addresses the urgent environmental issue of climate change, focusing specifically on the role of local food, which is produced and consumed locally, in helping to reduce carbon emissions by eliminating the need for long-distance transportation. Through quantitative analysis, this study elucidates the potential benefits of environmental impact achieved through the consumption of local food, i.e., the significant reduction in carbon emissions. Specifically, the consumption of local food has been found to yield an annual decrease of 2,421,296 tCO2 emissions, representing 2.5% of the Republic of Korea’s total greenhouse gas emissions from the transportation sector. This reduction further translates into an estimated economic value of USD 54.23 million (KRW 70.5 billion). These findings underscore the potential of local food consumption as a tangible strategy to overcome environmental problems. Moreover, the academic contribution of this study lies in its comprehensive analysis of the economic and empirical impacts of local food consumption on the environment. Moving forward, we propose policies such as supporting local food distribution networks, providing public education on local food, fostering local food industries, and implementing incentives to revitalize local food consumption.

Economic and Environmental Benefits of Heating of Poultry Houses with Geothermal Energy: A Case Study for Nevşehir Province of Turkey

In this study, as an example of the use of geothermal energy resources for the air-conditioning of animal shelters, the technical, economic and environmental gains that will be achieved in the case of heating a chicken coop with a total floor area of 480 m2 in Nevşehir province of Turkey in the winter months have been evaluated. For this purpose, a standard chicken coop with a length of 40 m, a width of 12 m and a height of 2.5 m and a capacity of 4320 chickens has been considered. The optimum indoor temperature for adult chickens is considered to be 22 °C. The total heat losses related to the different structural components of the considered standard house were determined. The annual total highest heat load for the poultry house was calculated as Qt = 197.32 kW. For geothermal resources suitable for house heating in the region, the amount of heat to be gained from the geothermal fluid to the house environment was calculated, taking into account the lowest physical properties (the lowest temperature Tgeo = 30 °C and the lowest flow rate mgeo = 30 m3/h). Since the amount of heat energy gained to the poultry environment with geothermal fluid (Qgeo=278.96 kW) is higher than the total heat losses (Qt = 197.32 kW) of the poultry house (Qgeo>Qt), it can be used for poultry heating with geothermal fluid. In case the considered poultry house is heated with geothermal energy, a total of 45073 kg of fuel will be saved annually from LPG consumption and 42186.4 kg of diesel fuel consumption will be saved. If Diesel or LGP fuel is used instead of geothermal fluid for poultry heating, the annual total fuel cost will be 266 211.6 TL for LPG usage and 274 585.2 TL for Diesel usage. In case the considered house is heated with geothermal energy, 136 571.2 kgCO2-eq or 133 798.3 kgCO2-eq from the annual total greenhouse gas emissions will save compared to the use of LPG and Diesel, respectively.

Finance and the environment: The eco‐impact of market‐ and institution‐driven development in Africa using land‐use‐adjusted metrics across sources of greenhouse gases

AbstractAfrica must ensure that its development trajectories are sustainable. In pursuit of viable policy pathways, this study examines the eco‐impact of the energy mix (Te) and financial development (FD) in selected African countries. The Te path is defined using the emission‐intensity paradigm, where positive trends indicate a strong dependence on fossil fuels, while negative trends suggest a shift toward greener energy sources. The FD impact is disaggregated to recognize the separate effects of market‐based (FM) and institution‐based (FI) development. This study utilized land‐use metrics across major greenhouse gas (GHG) sources, drawing data from a panel of 33 countries spanning from 1982 to 2021. It employs a novel instrumental‐variables approach for fitting panel‐data models, addressing cross‐sectional dependence issues and incorporating heterogeneous slope coefficients using the mean‐group estimator. Empirical findings reveal that positive trends in Te have a significant and positive impact on total GHG emissions (GHGe), whereas FM has a negative and significant effect on GHGe, suggesting its active role in mitigating climate impacts. The disaggregation of GHGe highlights the distinct impacts on CO2 (CO2e), nitrous oxide (N2Oe) and methane (CH4e) emissions. Economic affluence positively impacts CH4e, while positive trends in Te primarily increase CO2e. FI significantly reduces N2Oe, while FM notably decreases CO2e. Furthermore, FI has a significant negative impact on the emission intensity of Te, indicating its role in promoting green energy transition. These findings underscore the necessity for nuanced policy interventions that integrate FD with environmental objectives, promote green energy transition and address land‐use challenges.

CO2 adsorption and storage over FAU-zeolites for environmental remediation: Understanding the role of oxygen vacancy and promotor loading

The CO2 level is rising in the atmosphere and has reached well above 400 ppm. Thus, there is growing concern about increasing CO2 levels in the atmosphere as it is a greenhouse gas, constituting 20–25 % of total greenhouse gas emissions. CO2 is quite a resilient molecule and is a by-product of any combustion-driven process. The CO2 conversion is a non-spontaneous process due to its strong stability. The IEA and IPCC constantly mandate laws to monitor and regulate CO2 emissions in the atmosphere. One efficient way is to scrub off CO2 coming out of the exhaust. Several technologies have been developed around this concept, like adsorption and absorption. In this work, we have used zeolite for CO2 adsorption. Four different zeolites with a Si/Al ratio of one, which possess varied pore diameters of 3 Å, 4 Å, 5 Å and 10 Å are tested for CO2 adsorption. The zeolite with the pore diameter of 5 Å exhibited the best performance, which adsorbed 0.3 mmol/g (13.203 mg/g) of CO2. The adsorption capacity of zeolites is further enhanced by creating oxygen vacant sites and loading sodium (Na) promotor. The creation of oxygen vacancy ∼11 % for MZE600 sample raises the CO2 adsorption by 1.6 times compared to the ZE. Various concentrations of Na promotor are loaded on zeolite namely 5,10,15,20,25,35 %. About 11.97 mmol/g (527 mg/g) of CO2 adsorption was observed for 25 % loading of Na promotor on zeolite (M25NaZE). With the sequential increase in promotor loading (up to 25 %), CO2 adsorption increases. Further increase in loading reduces the CO2 adsorption, attributed to blockage of pores on sorbent and plausible agglomeration of the promotor. The M25NaZE sample is stable for a minimum of 10 regeneration cycles and exhibits linear response to variation in CO2 concentration from 2.5 % to 16 % and feed flow rate of 50–500 mL/min.

Influence of the Depth of Nitrogen-Phosphorus Fertilizer Placement in Soil on Maize Yielding and Carbon Footprint in the Loess Plateau of China

Deep fertilization is a beneficial approach for reducing nitrogen losses. However, the effects of various fertilization depths on maize (Zea mays L.) productivity and environmental footprints have not been thoroughly understood. Therefore, a field experiment was conducted to investigate the effects of different fertilization depths of 5 cm (D5), 15 cm (D15), 25 cm (D25), and 35 cm (D35) on maize productivity and environmental footprints. Reactive nitrogen (Nr) losses and greenhouse gas (GHG) emissions were assessed using life cycle analysis. We hypothesized that deep fertilization can obtain lower carbon and nitrogen footprint. The results indicated that deep fertilization decreased the N2O and NH3 emissions while increasing the CH4 uptake. Compared with D5, D15 resulted in an increase in total GHG emissions and carbon footprint (CF), whereas D25 decreased by 13.0% and 23.6%, respectively. Compared with D5, the Nr losses under D15, D25, and D35 conditions was reduced by 11.3%, 17.3%, and 21.0%, respectively, and the nitrogen footprint (NF) was reduced by 16.0%, 27.4%, and 19.0%, respectively. The maize yield under D15 and D25 increased by 5.7% and 13.8%, respectively, compared with the D5 treatment, and the net economic benefits of the ecosystem increased by 7.1% and 17.1%, respectively. In summary, applying fertilizer at a depth of 25 cm can significantly reduce the environmental footprints and increase maize productivity, making it an effective fertilization strategy in the Loess Plateau region of China.

Environmentally sustainable opportunities for health systems: metered-dose inhaler prescribing, dispensing, usage, and waste at The Ottawa Hospital

BackgroundThe carbon footprint of Canada's health sector is among the worst in the world, responsible for 4·6% of Canada's total greenhouse gas emissions. A quarter of emissions from Canada's health sector are linked to pharmaceuticals, including metered dose inhalers (MDIs). MDIs use propellants, such as hydrofluorocarbons, which act as greenhouse gas emissions and contribute to the health-care sector's overall carbon footprint. The objective of this study was to describe MDI prescribing, dispensing, usage, and waste patterns at The Ottawa Hospital (Ottawa, ON, Canada). Secondary objectives included estimating the monetary and carbon cost of current practice and the potential benefits and costs of switching to the more environmentally friendly dry powder inhalers. MethodsIn this retrospective point-prevalence cohort study, we identified 100 consecutive patients from medical and surgical services at both campuses of The Ottawa Hospital from health records discharged from medical and surgical services and who were prescribed at least one MDI during their admission. Medical records were reviewed and data related to demographics, MDI prescribing, dispensing, usage, and wastage were collected using a pre-piloted electronic case report form. Financial cost was calculated using local costing estimates and carbon cost was calculated using published estimates. FindingsBetween Jan 1, 2023, and June 1, 2023, we collected data for 100 eligible patients, of whom 60 (60%) were female and 90 (90%) were admitted to hospital medicine wards (10% from surgical wards). The median length of stay was 7 (range 1–47) days. The most common inpatient diagnoses were respiratory tract infections in 43 (43%) of 100 patients and chronic obstructive pulmonary disease exacerbations in 28 (28%) of 100 patients. The median number of MDIs prescribed during a patients stay was two (range one to 15) and the median number dispensed was one (range one to seven). For formulary options of MDIs, of the 200 (range 30–1400) actuations dispensed per patient, 8% were used, representing 92% wastage. During the audit, 315 MDIs were dispensed in total, of which 97 were not used at all. InterpretationMDIs are significant contributors to the carbon footprint attributed to pharmaceutical use in hospitals. This study suggests that 90% of MDI doses are wasted, showing that there is substantial room for improvement. FundingNone.

Multi-tier life cycle assessment for evaluating low carbon strategies in soil remediation

Addressing soil pollution and achieving global carbon neutrality requires low carbon remediation practices. When selecting the optimal remediation techniques, a comprehensive model is required to assess the environmental and economic impacts accurately. In the present study, a spatial three-tier framework that combines process cycle assessment (PLCA), Input output analysis (IOA) and Multi-Regional Input Output analysis (MRIOA) has been used to evaluate the greenhouse gas (GHG) emissions of three commonly used remediation alternatives at a contaminated site in Hubei Province, China, as well as the indirect GHG emissions of the industry chain at provincial and national scale. The three remediation techniques were coprocessing in a cement kiln (CCK), ex-situ solidification and stabilization (ESS), and soil washing (SLW). Using a tiered hybrid life cycle assessment (THLCA) approach, the results demonstrated the importance of including off-site emissions in life cycle assessments. It was found that CCK had the lowest total GHG emissions among the three alternatives. Off-site greenhouse gas (GHG) emissions associated with three soil remediation alternatives vary significantly, with CCK exhibiting the lowest levels and ESS the highest. Soil remediation emissions mainly affected Hubei Province, with varying spillover effects on other regions, such as Inner Mongolia, Shanxi, Liaoning, and Gansu, which supplied material resources and power supply for the soil remediation project. The production and supply of electricity and heat (PSE) sector contributed the most to off-site emissions, accounting for 56.05%, 67.76%, and 67.30% of total emissions for CCK, ESS, and SLW, respectively. Overall, the present study provides fresh insights to support a more holistic low-carbon assessment of soil remediation options.

Use of ceramic fiber modified with ferrites for the cleaning of flue gases of graphitization furnaces

Gaseous emissions of industrial enterprises as a result of their economic activities adversely affect the ecological situation, and even worsen the sanitary and hygienic working conditions of the personnel. Carrying out chemical reactions in the furnace equipment of metallurgical and electrothermal production, as a rule, lead to the formation of gases containing various toxic impurities, including carbon monoxide, the disposal of which is an important environmental task. As the calculations show, the total amount of annual CO emissions in Ukraine is 704344.218 t/year, which in percentage terms is 31.42% of the total emissions of pollutants and greenhouse gases, except for carbon dioxide - 2242020.75 t/year. The release of significant amounts of poisonous CO into the atmosphere is a serious problem that must be solved at the level of industrial production. One of the effective directions in the field of purification of industrial gas emissions from toxic carbon monoxide is the application of catalytic technologies due to the use of compositions based on transition metals, especially ferrite materials. Recently, systems for neutralizing toxic gases, including glass fiber catalysts, have become widely popular. The study of the CO oxidation process was carried out on a flow-type installation with a stationary weight of the catalyst. Catalytic purification of the gas mixture from CO was studied in the range of 50-450 °C. The concentration of carbon monoxide in the initial gas mixture at the entrance to the reactor was varied in the range of 1-2 vol. %. If necessary, helium was used as an inert gas. Ceramic fiber was used as a fiberglass support for catalytic systems for the oxidation of gaseous emissions containing CO. Ferrite catalysts were applied to ceramic fiber by the method of impregnation from sulfate solutions of iron, copper, and potassium bichromate. From the temperature dependences of the conversion of carbon monoxide with a concentration of 1-2% on ferrite catalysts on a ceramic fiber carrier, it can be seen that 100% conversion of carbon monoxide is not achieved even at a temperature of 450 ºС. In the case of using a mixture of magnetite and copper ferrite, the degree of conversion of CO was 97% at temperatures above 300 ºС and stably ensured the neutralization of CO until the conversion degree of 98% was reached at a temperature of 450 ºС. At a temperature of 450 ºС, the highest degree of conversion of 99% was ensured by using chromium ferrite, but the specified chromium-ferrite catalyst at a temperature of 400 ºС provided a slightly lower oxidation efficiency, that is, the specified catalyst has less advantages for use in fluctuating gas temperatures in industrial conditions. When magnetite and copper ferrite were used separately, the degree of CO conversion was 40% and 75%, respectively. Therefore, the conducted studies showed that the use of ceramic fiber modified with ferrites can be effectively used for the purification of flue gases of electrode graphitization furnaces, in particular, the neutralization of toxic carbon monoxide. Obtaining ceramic fiber modified with ferrite material does not require significant capital investments, as it is based on the use of liquid waste from etching, copper plating, and chrome plating of galvanic production. Laying ceramic fiber on top of the thermal insulation of the graphitization furnaces of electrode production will also reduce the inflow of oxygen into the porous space and reduce the formation of carbon monoxide, which will contribute to the improvement of the ecological situation at the electrode production. The obtained results on the use of ceramic fiber modified with ferrite material as a catalyst for the neutralization of carbon monoxide are a highly effective and affordable measure to reduce the man-made burden of electrode production on the environment.