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The current data on climate change and environmental degradation are dramatic. The consequences of these changes are already having a significant impact on people's health. Physicians - as advocates of the patients, but also as citizens - have an ethical obligation to be involved in efforts to stop these changes. The European Federation of Internal Medicine (EFIM) strongly encourages the Internal Medicine societies and internists across Europe to play an active role in matters related to climate change and environmental degradation. At a national level, this includes advocating the adoption of measures that reduce greenhouse gas (GHG) emissions and environmental degradation and contributing to policy decisions related to these issues. At a hospital level and in clinical practice, supporting actions by the health sector to reduce its ecological footprint is vital. At the level of EFIM and its associated internal societies, promoting educational activities and developing a toolkit to prepare internists to better care for citizens who suffer from the consequences of climate change. In addition to advocating and implementing effective actions to reduce the ecological footprint of the health industry, recommending the introduction of these themes in scientific programs of Internal Medicine meetings and congresses and the pre- and postgraduate medical training. At a personal level, internists must be active agents in advocating sustainable practices for the environment, increasing the awareness of the community about the health risks of climate change and environmental degradation, and being role models in the adoption of environmentally friendly behaviour.

This study aimed to investigate the influence of herbal residues on the fermentation quality and ruminal fermentation of paper mulberry silage. Clove, mint, and purple perilla residues were used as additives. Silage treatments were designed as control (no additives), 5% of clove, 5% of mint, and 5% of purple perilla. After 21 and 75 days of fermentation, the fermentation characteristics, bacterial communities, and ruminal greenhouse gas emissions in vitro incubation of paper mulberry were analyzed. The results showed that the used herbal residues could reduce the protein losses in paper mulberry silage based on the lower contents of ammoniacal nitrogen and nonprotein nitrogen. Compared with control, higher lactic acid and propionic acid contents were observed in the silages treated with mint and purple perilla but with a higher acetic acid content in clove treatment. Real-time sequencing technology (single-molecule real-time) revealed that Lactobacillus was the dominant bacteria in all silages at the genus level, whereas the bacterial abundance in the treated silages differed greatly from control at the species level. Lactobacillus hammesii abundance was the highest in control, whereas Lactobacillus acetotolerans was the first predominant in the treated silages. All the additives enhanced the digestibility of in vitro dry matter significantly. However, purple perilla decreased the production of total gas, methane, and carbon dioxide. The findings discussed earlier suggested that herbal residues have potential effects in improving fermentation quality, reducing protein loss, and modulating greenhouse gas emissions in the rumen of paper mulberry silage by shifting bacterial community composition.

China's paper industry development is rapid, but the recycling rate of China's waste paper has been low all the time. Meanwhile, material flow analysis can help determine the flow of waste paper, and life cycle assessment (LCA) is the methodological framework for quantifying greenhouse gas emissions. Therefore, present study integrates these two methods into the model construction of China's waste paper recycling decision system. Present study constructs a benchmark model of China's waste paper recycling decision system in 2017, focusing on the impact of nonstandard waste paper recycling on the economic and environmental benefits of China's domestic waste paper recycling system. This model construction is followed by sensitivity analysis of the relevant parameters affecting the efficiency of the waste paper recycling system. Finally, present study forecasts the system's economic benefits and greenhouse gas (GHG) emissions in the context of integrating and regulating nonstandard recycling vendors. The results show that the economic benefit of China's waste paper recycling in 2017 is approximately 458.3 yuan/t and that the GHG emissions are 901.1 kgCO2eq. The standard recovery rate and nonstandard recovery acceptance rate will both have a significant impact on the system's economic benefits and improve the GHG emissions structure. In the context of integrating nonstandard recycling enterprises and individual recycling vendors, the economic benefits will rise to 3312.5 yuan/t in 2030, while GHG emissions will rise to 942.9 kgCO2eq. Present study can play a certain guiding role for policy makers in formulating waste paper recycling industry specifications and formulating relevant policies.

Alkaline residuals, such as wood ash and lime mud generated from pulp and paper mills, could be recycled as liming agents in sugar maple (Acer saccharum Marsh.) forests affected by soil acidification. The objectives of this study were (1) to evaluate soil chemistry, in particular soil acidity, after the application of three alkaline residuals from the pulp and paper industry, and (2) to determine if these alkaline residuals altered soil greenhouse gas (GHG) emissions as a result of the change in soil pH or due to their chemical composition. Soil properties and GHG fluxes were monitored for two years after alkaline residuals were applied to six forest sites dominated by sugar maple in southeastern Quebec, Canada. Each site received six treatments: wood ash applied at 5, 10 and 20 t ha−1, lime mud (7.5 t ha−1), a mixture of slaker grits and green liquor sludge (7 t ha−1) and an unamended control. These treatments had acid-neutralizing power from 0 to 9 t ha−1. All alkaline residuals buffered soil acidity as a function of their neutralizing power, and more neutralization occurred in the forest floor layer than in the underlying mineral soil. In the forest floor, the alkaline residual treatments significantly increased pH by more than one unit, nearly doubled the base saturation, and reduced exchangeable acidity, Al and Fe concentrations compared to control plots. The CO2 and N2O fluxes were lower after application of alkaline residuals, and this was related to the soil pH increase and the type of alkaline residual applied. Lime mud was more effective at reducing GHG fluxes than other alkaline residuals. We conclude that these alkaline residuals can effectively counteract soil acidity in sugar maple forests without increasing soil GHG emissions, at least in the short term.

The paper by K. L. Blaxter and J. L. Clapperton (1965) 'Prediction of the amount of methane produced by ruminants.

Large areas of mine tailings are reclaimed by applying organic amendments such as paper mill sludge (PMS). Although mining industries can use PMS freshly generated by paper mills, operational constraints on paper industries make temporary landfilling of this material an unavoidable alternative for the paper industries, creating the most prominent PMS source for mining industries. This study aimed to quantify soil greenhouse gas (GHG) emissions (N2O, CO2, and CH4) after application of landfilled PMS (LPMS; i.e., excavated from a landfill site at a paper mill) and LPMS combined with a seeding treatment of white clover (Trifolium repens L.) on nonacidic mine tailings site prior to reforestation. Soil N2O, CO2, and CH4 fluxes were measured after applications of 50 and 100 Mg dry LPMS ha−1 during two consecutive snowfree seasons on two adjacent sites; LPMS was applied once in the first season. The LPMS application increased N2O emissions (7.6 to 34.7 kg N2O-N ha−1, comprising 1.04 to 2.43% of applied N) compared with the unamended control during the first season; these emissions were negligible during the second season. The LPMS application increased CO2 emissions (~5800 to 11,400 kg CO2–C ha−1, comprising 7 to 27% of applied C) compared with the unamended control on both sites and in both seasons. Fluxes of CH4 were negligible. White clover combined with LPMS treatments did not affect soil GHG emissions. These new GHG emission factors should be integrated into life-cycle analyses to evaluate the C footprint of potential symbioses between the mining and paper industries. Future research should focus on the effect of PMS applications on soil GHG emissions from a variety of mine tailings under various management practices and climatic conditions to plan responsible and sustainable land reclamation.

As China's demand for paper products increases, China's paper industry faces enormous pressure to reduce greenhouse gas emissions. By using material flow analysis in combination with input-output analysis, this study measured the waste paper recovery rate in a more accurate method and analyzed the impact of waste paper recycling on the carbon emissions from China's paper industry. China's waste paper recovery rate estimated in this study was close to 70% in 2017, much higher than that of 48% obtained with the traditional method. The regression results displayed a negative relationship between waste paper recovery rate and CO

The technical design project, Carbon Capture, Utilization and Storage, explores the feasibility of converting carbon dioxide captured from stack gas from a natural gas power plant, Pastoria Energy Facility, into diesel. The plant is retrofitted with an amine scrubbing system to remove and isolate the carbon dioxide (CO2) gas from the power plant exhaust using monoethanolamine (MEA). The CO2 is then fed into a reverse water-gas shift reactor followed by a Fischer-Tropsch reactor, which converts the CO2 into carbon monoxide (CO) and a variety of hydrocarbons, respectively. The final recommended solution from mainly an economic standpoint is to sequester captured CO2 as opposed to pursuing synthetic fuel generation. The overall capital cost for the recommended option is $56,805,108 with utility costs of $26,392,029 per year, labor costs of $1,664,600 per year, and CO2 transportation and storage costs of $6,411,006 per year. Overall, this project would remove 56,000 kg/hr of CO2 from the atmosphere, a 27% reduction from the total plant emissions, at a process cost of $34,804,505 per year. This cost for carbon removal can be offset by earned carbon credits of $6,740,000 per year and a price increase of 3.6% for 10 years and 3.0% after in electricity sold by the plant. Climate change brought on by the excessive release of greenhouse gases, namely CO2¬, is negatively impacting agriculture on a global scale. The Science, Technology, and Society analysis of this thesis explores specifically the cultivation and harvest of Arabica coffee, which is under great duress due to a perfect storm of shifting climate conditions and poor harvest techniques. Carbon capture, utilization and storage (CCUS) technologies have the potential to mediate a portion of greenhouse gas (GHG) emissions by capturing point source CO2 emissions, but even with the implementation of these technologies, farmers must still consider adaptation techniques to reduce the potential for extinction of Coffea arabica. China and the United States are the source of nearly 50% of global greenhouse gas emissions (U.S. EPA, 2014). The top 10 coffee consuming countries per capita all have a human development index (HDI) greater than 0.90, which reflects a very developed nation (World Atlas, 2018). That being said, Greater than 90% of coffee production is located in developing countries (Ponte, 2002), and the residents of these areas are found to be extremely vulnerable to climate change. These communities feel the effect on their livelihood through reduction of suitable locations for coffee cultivation brought on by greenhouse gas emissions. Technological determinism is a theory of STS that applies to the analysis of the effect of climate change on the cultivation of Arabica coffee. This framework emphasizes the deterministic effect of technology on societal norms and cultures of affected areas based upon its interaction with situational circumstance and ideology of localities impacted. In this specific case of arabica coffee harvesting in developing nations, farmers are left with virtually no option but to adapt according to the effects of climate change that they experience. Personal opinions from local Charlottesville coffee shop personnel that source coffee beans through the use of a short survey was gathered to support the analysis. Primary data was also gathered through the use of published academic journals that include interviews from rural farmers located in the geographical areas of interest themselves. It was found that climate change is projected to have an overwhelming negative effect on the cultivation of Arabica coffee over the next few decades. Farmers are unlikely to have a full grasp of the changes brought on their livelihood caused by climate change, since they are mostly located very far from the epicenter of greenhouse gas emissions and lack the education necessary for a depth of understanding of climate change science. No single technology has the ability to save Arabica coffee from the effects of climate change. The coffee industry will not prevail due to simply the implementation of CCUS technologies at certain power producing facilities. That being said, these technologies implemented in concert with more sustainable agricultural practices and increased education of farmers has the potential to prolong the lifespan the coffee industry.

In 2015, a CO2/CH4/CO CRDS was installed at the Izaña station (Tenerife). We present the acceptance tests and the processing of raw data applied through novel numerical codes. The ambient measurements performed, and their comparison with other continuous in situ measurements are shown. We determine: a slight CO2 correction that takes into account changes in the inlet pressure/flow rate; the H2O correction for CO in a novel way; and the origin of the CRDS-flow inlet pressure and H2O dependences. The acquisition of the instrument was largely financed by European ERDF funds through the Spanish R+D infrastructure project AEDM15-BE-3319 of the Spanish “Ministerio de Economía, Industria y Competitividad”

We present lower/middle tropospheric column-averaged CH4 mole fraction time series measured by nine globally distributed ground-based FTIR (Fourier transform infrared) remote sensing experiments of the Network for the Detection of Atmospheric Composition Change (NDACC). We show that these data are well representative of the tropospheric regional-scale CH4 signal, largely independent of the local surface small-scale signals, and only weakly dependent on upper tropospheric/lower stratospheric (UTLS) CH4 variations. At Ny-Ålesund and Izaña, the FTIR work has received funding from the European Community’s Seventh Framework Programme ([FP7/2007–2013]) under grant agreement no. 284421 (see Article II.30. of the Grant Agreement). At Izaña has also received funding from the Ministerio de Economía and Competitividad from Spain for the project CGL2012-37505 (NOVIA project). This study has strongly benefited from work made in the framework of the project MUSICA, which is funded by the European Research Council under the European Community’s Seventh Framework Programme (FP7/2007–2013)/ERC grant agreement number 256961.

Ground-based Fourier transform infrared (FTIR) measurements of solar absorption spectra can provide ozone total columns with a precision of 2% but also independent partial column amounts in about four vertical layers, one in the troposphere and three in the stratosphere up to about 45km, with a precision of 5–6%. We use eight of the Network for the Detection of Atmospheric Composition Change (NDACC) stations having a long-term time series of FTIR ozone measurements to study the total and vertical ozone trends and variability, namely, Ny-Ålesund (79° N), Thule (77° N), Kiruna (68° N), Harestua (60° N), Jungfraujoch (47° N), Izaña (28° N), Wollongong (34° S) and Lauder (45° S). This study has been supported by the EU FP7 project NORS, the ESA PRODEX project A3C, as well as the AGACC-II project within the Science for a Sustainable Development research program funded by the Belgian Science Policy Office.

1.Neotropical peatlands emit large amounts of methane (CH4) from the soil surface, but fluxes from tree stems in these ecosystems are unknown. In this study we investigated CH4 emissions from five tree species in two forest types common to neotropical lowland peatlands in Panama.2.Methane from tree stems accounted for up to 30% of net ecosystem CH4 emissions. Peak CH4 fluxes were greater during the wet season when the water table was high and temperatures were lower. Emissions were greatest from the hardwood tree Campnosperma panamensis, but most species acted as emitters, with emissions declining exponentially with height along the stem for all species. 3.Overall, species identity, stem diameter, water level, soil temperature and soil CH4 fluxes explained 54% of the variance in stem CH4 emissions from individual trees. On the landscape level, the high high emission from Campnosperma panamensis forest these emitted comparable amounts of CH4 from tree stems as mixed forests at 340 kg CH4 day‐1 during flooded periods despite their substantially lower areal cover. 4.We conclude that emission from tree stems is an important emission pathway for CH4 flux from Neotropical peatlands, and that these emissions vary strongly with season and forest type.

The acceptance of combined pre-composting and vermicomposting systems is increasing because of the advantage in rapidly stabilizing organic wastes and reducing emission of greenhouse gasses (GHG). However, GHG emission during the pre-composting phase is often neglected when evaluating the system. This study aimed to quantify GHG emission from a combined pre-composting and vermicomposting system and to investigate the effects of earthworms on GHG emission. A combined system using Eisenia fetida was employed to stabilize maize stover and cow dung (mixing ratio 60:40). The inoculating densities were 60 (T1), 120 (T2), and 180 (T3) earthworms per kilogram of substrate. A traditional composting system without earthworms was set as a control (T0). The results indicated that earthworms increased CO2 while decreased CH4 and N2O emissions compared to the control. Higher emission of CO2 suggested that the earthworms promoted the degradation of the substrates. Lower emission of CH4 and N2O showed the advantage of the combined system because CH4 and N2O possess extremely higher global warming potential than that of CO2. T2 is recommended for stabilizing maize stover and cow dung when making a tradeoff between stabilization rate and reduction of GHG. The percentages of GHG emission during pre-composting relative to total GHG emission in T1, T2, and T3 were 34%, 35%, and 30%, respectively. GHG emission is non-negligible when using a combined system, especially the emission of GHG during the pre-composting phase cannot be ignored.

Lignocellulose comprises a significant portion of municipal solid waste (MSW) - 40-70% in developed countries, including paper, wood, and yard waste. Cellulose and hemicellulose are often shielded by lignin, posing a barrier to waste decomposition and landfill gas generation. Unfortunately, lignin is resistant to microbial degradation under low-oxygen conditions that normally occur in MSW landfills. The bacterium strain TAV5, microaerophilic and member of phylum Verrucomicrobia, isolated from the hindgut of the Reticulitermes flavipes termite, the most widely distributed subterranean termite in North America. Its genome contains genes associated with methylotrophic competency which code for enzymes that structurally modify lignin. The overall goal of this research was to use TAV5 to modify lignin and boost methane production from MSW. Batch-scale reactors (125mL) were filled with paper, yard, or wood waste, and four ratios of mixed of waste. Reactors were seeded with different ratios of TAV5 to anaerobic digester (AD) microorganisms (representing landfill anaerobic microorganisms). Based on batch tests, optimal ratios of TAV5 to AD microorganisms were used to seed wastes (mixed, yard, and wood) in 6-gallon reactors. Addition of TAV5 increased methane production from mixed waste, yard waste, and wood, by 49%, 34%, and 297%, respectively. TAV5 decreased acid soluble lignin by 7-39%, depending on waste type. TAV5 grown under aerobic conditions and room temperature (not requiring a heated anaerobic chamber) was found to remain viable and increase methane production under low-level oxygen conditions (1-2%). This finding will potentially lessen costs for growing large volumes of it for seeding landfills.

This paper presents the greenhouse gas (GHG) emissions during ultrasonication of sludge and anaerobic digestion (AD) of the ultrasonicated sludge using mass-energy balance. Computation of the net energy (energy recovered - energy input) revealed that high solids concentration with low sonication specific energy provides positive net energy. Moreover, the GHG emissions can be minimised at low sonication specific energy input and high solids concentration compared to that of the control without sonication. Increase in temperature of sludge during sonication will reduce the energy input required for raising the sludge temperature to AD temperature and thus decreases the GHG emissions. With energy recovery from the methane produced in AD, the total GHG emissions can further be reduced, lower than that without energy recovery from methane.

Currently, sustainable utilization, including recycling and valorization, is becoming increasingly popular in waste management. Black soldier fly larvae (BSFL) can convert the carbon (C) and nitrogen (N) from organic waste into biomass and improve properties of the substrate to reduce greenhouse gas and NH3 emissions. In this study, the recycling of C and N and the emissions of greenhouse gas and NH3 during BSFL bio-treatment of mixtures of pig manure and corncob were investigated under different C/N ratios. The results indicated that initial C/N ratios of feedstock are a crucial parameter affecting the biomass generation of larvae. The BSFL recycled approximately 4.17–6.61% of C and 17.45–23.73% of N from raw materials under different C/N ratios. Cumulative CO2, CH4, NH3, and N2O emissions at the different C/N ratios ranging from 15 to 35 were 107.92–151.68, 0.08–0.76, 0.14–1.17, and 0.91–1.18 mg kg−1, respectively. Compared with conventional composting, BSFL treatment could reduce the total greenhouse gas emissions by over 90%. The study showed that bio-treatment of mixtures of pig manure and corncob with a proper C/N ratio by BSFL could become an avenue to achieve higher nutrient recycling, which is an eco-friendly process.

The reduction of greenhouse gases (GHG) emissions is important challenge in the wastewater treatment plants. In this way, the present study aimed to evaluate the GHG emissions and carbon dioxide fixation by duckweed ponds (DWP) applied to treat municipal wastewater in a polishing stage. Two pilot DWP (3000 L) were operated in a series with real wastewater receiving a flow rate of 200 L d−1 and organic load rate of 39 g COD ha−1 d−1. Beyond the standard physicochemical parameters for wastewater monitoring, the gases emissions from pond surface were measures by using a static flux chamber with infrared probes installed inside to detect CO2 and CH4 concentration. Operating the DWP with a load of 18.1 kg TN ha−1 d−1 and 2 kg TP ha−1 d−1, across 425 days of monitoring, higher COD and nutrient removal efficiency was identified (79%, 93% and 84% for COD, TN and TP, respectively). The CO2 emission rate ranged from 3048 to 6017 mg CO2 m−2 d−1 and the fixation rate ranged from 19,592 to 42,052 mg CO2 m−2 d−1. Methane emission was not detected (less than 0.1%). Moreover, low abundance of archaeal community was identified in both DWP. The results showed that in presented conditions, under low COD loading rate DWP could fix at least three times more CO2 than it emits, highlighting the sustainability of this natural technology.

Addition of sulfuric acid (H2SO4) to liquid dairy manure (slurry) reduces methane (CH4), nitrous oxide (N2O), and ammonia (NH3) emissions. There is interest in understanding how gaseous emissions respond to decreasing rates of acidification, to determine economically optimum application rates. Acidification rates were tested ranging from 0 to 2 g sulfuric acid (H2SO4) L−1 slurry in six meso-scale outdoor storage tanks, each filled with 10.6 m3 slurry and stored for 114 d. Results showed that the rate of acidification for maximum inhibition of CH4 and NH3 emissions varied markedly, whereas N2O reductions were modest. Reductions of CH4 increased with acid rate from 0 to 1.2 g L−1, with no additional response beyond >1.2 g L−1. In contrast to CH4, inhibitions of NH3 showed a linear response across all rates, although reductions were ≤ 30%. Thus, higher acidification rates would be required to achieve greater NH3 emission reductions. Our findings indicate that achieving >85% NH3 emissions reductions would require 4 × more acid than achieving >85% CH4 reductions. Decisions on optimum H2SO4 rates will depend on the need to mitigate CH4 emissions (the primary greenhouse gas emitted from stored liquid manure) or reduce NH3 emissions (which is regulated in some regions). These results will help develop guidelines related to the potential costs and benefits of reducing emissions through acidification.

Simultaneous on‐chip sensing of multiple greenhouse gases in a complex gas environment is highly desirable in industry, agriculture, and meteorology, but remains challenging due to their ultralow concentrations and mutual interference. Porous microstructure and extremely high surface areas in metal–organic frameworks (MOFs) provide both excellent adsorption selectivity and high gases affinity for multigas sensing. Herein, it is described that integrating MOFs into a multiresonant surface‐enhanced infrared absorption (SEIRA) platform can overcome the shortcomings of poor selectivity in multigas sensing and enable simultaneous on‐chip sensing of greenhouse gases with ultralow concentrations. The strategy leverages the near‐field intensity enhancement (over 1500‐fold) of multiresonant SEIRA technique and the outstanding gas selectivity and affinity of MOFs. It is experimentally demonstrated that the MOF–SEIRA platform achieves simultaneous on‐chip sensing of CO2 and CH4 with fast response time (, Porous metal–organic frameworks are provided with excellent gas adsorption selectivity due to their extremely high surface areas. Integrating it into the multiresonant surface‐enhanced infrared absorption platform overcomes the shortcomings of poor selectivity in gas sensing and enables simultaneous on‐chip sensing of greenhouse gases. Importantly, the strategy shows a competitive advantage in terms of response time, accuracy, footprint, and linearity.

Incorporating socio-economic considerations (SECs) into national biosafety regulations regarding genetically modified (GM) crops have opportunity costs. Australia approved the cultivation of GM canola through a science-based risk assessment in 2003, but allowed state moratoria to be instituted based on potential trade impacts over the period 2004 to 2008 and 2010 in the main canola growing states. This analysis constructs a counterfactual assessment using Canadian GM canola adoption data to create an S-Curve of adoption in Australia to measure the environmental and economic opportunity costs of Australia's SEC-based moratoria between 2004 and 2014. The environmental impacts are measured through the amount of chemical active ingredients applied during pest management, the Environmental Impact Quotient indicator, and greenhouse gas emissions. The economic impacts are measured through the variable costs of the weed control programs, yield and the contribution margin. The environmental opportunity costs from delaying the adoption of GM canola in Australia include an additional 6.5 million kilograms of active ingredients applied to canola land; a 14.3% increase in environmental impact to farmers, consumers and the ecology; 8.7 million litres of diesel fuel burned; and an additional 24.2 million kilograms of greenhouse gas (GHG) and compound emissions released. The economic opportunity costs of the SEC-based moratoria resulted in foregone output of 1.1 million metric tonnes of canola and a net economic loss to canola farmers' of AU$485.6 million. The paper provides some of the first quantified, post-adoption evidence on the opportunity cost and environmental impacts of incorporating SECs into GM crop regulation.

The aim of this work was to evaluate simultaneously the effect of produced ethanolic biodiesel from several feedstocks (soybean, crambe, macaw, sunflower, and waste cooking oil) and engine operational conditions (low and high engine speed) during combustion of biodiesel/diesel blends on the N2O, NOx, NO, CO2, and CO emission levels in the atmosphere. The biodiesel samples were prepared in one and/or two reaction steps, according to the acid index of each raw material, by esterification using H2SO4 and/or chemical transesterification using sodium ethoxide, both, through ethanolic route. The quality of the produced biodiesels was confirmed by ASTM/EN specifications. Then, biodiesel/diesel blends were prepared according to the following proportions: 10% (B10), 15% (B15), 25% (B25), and 50% (B50). In general way, all raw materials under combustion at low and high engine speed contributed to the formation of NOx and this effect was more drastically increased as the biodiesel concentration in the blends increases. N2O presented a similar behavior except for blends containing crambe and macaw biodiesel whose emissions were slightly reduced as a function of biodiesel content in these blends. Then, Principal component analysis (PCA) was applied to discriminate the effect of engine operating conditions, biodiesel kind, and biodiesel content in the blends during their combustion on the exhaust emissions. The attained results point to crambe and macaw as more environmentally sustainable feedstocks for biodiesel production because they generate less greenhouse gas emissions. These results are particularly attractive considering that, both, crambe and macaw are non-edible feedstocks with great potential for biodiesel production.

The environmentally safe disposal of the large quantity of orange peels waste produced each day causes economic and environmental problems, which after conversion into biochar via pyrolysis technique might be used as an effective soil amendment. In this study, a 90-day incubation experiment was conducted to investigate the effects of orange peel waste and waste-derived biochar amendments on greenhouse gas emissions (GHG), soil biochemical properties, and soil enzyme activities. There were five treatments with different amendment levels: control without an amendment (Control), orange waste 1% (W1), orange waste 2% (W2), orange waste biochar 1% (B1), and orange waste biochar 2% (B2). The results showed that, compared with control, the amendments decreased cumulative N2O emissions by 59.2% (B2), 45.2% (B1), 20.6% (W2) and 10.2% (W1), respectively; and increased cumulative CH4 emissions by 81.7% (W1), 84.4% (W2), 75.8% (B1) and 74.9% (B2), respectively. Cumulative CO2 emissions decreased for the B1 (29.3%) and B2 (43.5%) over the waste treatments. While soil pH, SOC, nitrate nitrogen (NO3--N) and enzyme activities (urease and catalase) were significantly increased with the passage of time from the biochar amendments, ammonium nitrogen (NH4+-N) and invertase activities did not show this trend with time. Our study suggests that orange peel waste conversion to biochar should be a viable alternate method of disposal since land application resulted in reduced GHG and improvements in soil fertility.

Substituting harvested wood products (HWP) for greenhouse gas (GHG) intensive nonwood materials in long-lived end uses has the potential to significantly reduce GHG emissions. To determine the mitigation effects of HWP substitution, we produced China-specific wood displacement factors (DFs) by HWP end use subcategory, defined as tonnes of carbon (tC) of reduced emissions per tC contained by the HWP substituted for typical alternative nonwood materials. The weighted average DFs for substituting HWP for nonwood materials in construction and furniture production in China were estimated to be 3.48 tC/tC and 1.36 tC/tC, respectively, or 2.90 tC/tC for HWP substitution when these two sectors were combined. If annual solid HWP consumption in China increased by 10% on the basis of 2014 consumption (an increase of 25.9 million m3 of HWP) and these HWP were used to substitute for GHG-intensive materials in construction and furniture production, 18.76 Mt C of emission reduction can be achieved annually. Substituting...

The interest in utilizing algae for wastewater treatment has been increased due to many advantages. Algae-wastewater treatment system offers a cost-efficient and environmentally friendly alternative to conventional treatment processes such as electrocoagulation and flocculation. In this biosystem, algae can assimilate nutrients in the wastewater for their growth and simultaneously capture the carbon dioxide from the atmosphere during photosynthesis resulting in a decrease in the greenhouse gaseousness. Furthermore, the algal biomass obtained from the treatment process could be further converted to produce high value-added products. However, the recovery of free suspended algae from the treated effluent is one of the most important challenges during the treatment process as the current methods such as centrifugation and filtration are faced with the high cost. Immobilization of algae is a suitable approach to overcome the harvesting issue. However, there are some drawbacks with the common immobilization carriers such as alginate and polyacrylamide related to low stability and toxicity, respectively. Hence, it is necessary to apply a new carrier without the mentioned problems. One of the carriers that can be a suitable candidate for the immobilization is zeolite. To date, various types of zeolite have been used for the immobilization of cells of bacteria and yeast. If there is any possibility to apply them for the immobilization of algae, it needs to be considered in further studies. This article reviews cell immobilization technique, biomass immobilization onto zeolites, and algal immobilization with their applications. Furthermore, the potential application of zeolite as an ideal carrier for algal immobilization has been discussed.

This study analyzed emissions characteristics of NH3 and greenhouse gases (i.e. N2O, CH4, and CO2) from a municipal sewage sludge aerobic composting plant. Samples were collected during different seasons in which ambient temperatures and aeration frequencies varied. Results revealed (1) the maximum gas emissions occurred during the mesophilic phase for N2O (22%–56%) and CH4 (65%–95%), and in the thermophilic phase for NH3 (84%–86%) and CO2 (65%–74%); (2) raising ambient temperatures promoted emissions of NH3 and greenhouse gases, while improved aeration frequency increased NH3 but decreased greenhouse gas emissions; (3) CO2 and N2O were found to be the key greenhouse gases emitted during aerobic composting according to assessment of the CO2 equivalent. The results obtained from this study suggest that adjusting ambient temperature to −3 to 5 °C and aeration frequency in composting workshops can be useful approaches for the reduction of NH3 and greenhouse gas emissions from municipal sewage sludge composting plants.

Methane (CH4) and nitrous oxide (N2O) emissions from two-stage membrane bioreactor (MBR) bio-augmented by Alcaligenes faecalis no. 4 during municipal solid waste leachate treatment were investigate...

Anaerobic digestion and incineration are widely used sewage sludge (SS) treatment and disposal approaches to recovering energy from SS, but it is difficult to select a suitable technical process from the various technologies. In this study, life-cycle assessments were adopted to compare the energy- and greenhouse gas- (GHG) emission footprints of two sludge-to-energy systems. One system uses a combination of AD with incineration (the AI system), whereas the other was simplified by direct incineration (the DI system). Comparison between three SS feedstocks (VS/TS: 57.61 -73.1 ds.%) revealed that the AI system consistently outperformed the DI system. The results of sensitivity analyses showed that the energy and GHG emission performances were mainly affected by VS content of the SS, AD conversion efficiency, and the energy consumption of sludge drying. Furthermore, the energy and GHG emission credit of the two systems increased remarkably with the increase in the VS content of the SS. For the high-organic-content sludge (VS/TS: 55%–80%), the energy and GHG emission credit of the AI system increase with the increase of AD conversion efficiency. However, for the low organic content sludge (VS/TS: 30%–55%), it has the opposite effect. In terms of energy efficiency and GHG performance, the AI system is a good choice for the treatment of high-organic-content sludge (VS/TS>55%), but DI shows superiority over AI when dealing with low organic content sludge (VS/TS

Two primary concerns of dairies that store manure wastewater in anaerobic ponds are greenhouse gas (GHG) emissions and unpredictable nutrient availability after applying it to forage crops. Solid-liquid separation of dairy manure wastewater with chemical coagulants significantly reduces the fraction of organic matter stored in anaerobic conditions. However, the effects of coagulants on methane emissions from ponds and nutrient availability following field application are not well understood. In this experiment, several metal salts and organic polymers were used to coagulate dairy manure wastewater for separation into solid (floc) and liquid (effluent) fractions. The coagulants tested were ferric sulfate, ferric chloride, polyaluminum chloride, Superfloc C-569, and chitosan. An anaerobic incubation of manure effluent to simulate liquid manure storage and an aerobic incubation of manure floc-amended soil to simulate field application were conducted with analysis of GHGs and carbon and nitrogen transformations. The treatment of chemically separating organic matter from manure wastewater effectively eliminated methane emissions under anaerobic conditions in the laboratory. In the solid manure fraction, organic carbon was stabilized in the chemically separated flocs, and, apart from flocs produced with ferric iron, nitrogen mineralization was reduced as well. Carbon dioxide emissions were also reduced from the flocs applied to soil compared with untreated manure solids.

Compost can realize the recycling of organic waste. However, it also emits NH3 and greenhouse gases (GHGs) to the environment, which leads to nitrogen loss and global warming. Adding additives to compost can alleviate the emission of NH3 and GHGs. The mechanism of nitrogen transformation and GHGs emission was studied with deer manure and corn straw as compost substrate, and biochar and zeolite as additives. The results showed that the addition of zeolite in compost is good for prolonging high-temperature composting time. The addition of zeolite reduced the transformation of NH3-N and the N2O emission. The addition of zeolite is beneficial to reduce nitrogen loss during composting. CH4 emission is an important factor affecting the global warming potential of composting, and it is necessary to improve ventilation conditions in order to alleviate anaerobic. This study is of great significance to reduce nitrogen loss and improve composting effect.

The aim of this study was to develop a new experimental setup to determine parallel the emissions of greenhouse gases (GHG) and volatile organic compounds (VOCs) from silage during the opening as well as the subsequent aerobic storage phase of the complete bale without wrapping film. For this purpose, a special silage respiration chamber was used in which a silage bale could be examined. The gas analysis (CO2, methanol, ethanol, ethyl acetate) of inlet, ambient and outlet air of the silage respiration chamber was carried out by photoacoustic spectroscopy. The gas samples taken inside the bale were analysed by gas chromatography for CO2, O2, CH4, and N2O. Three silage bales (grass and lucerne) as the smallest silage unit commonly used in practice were examined. The emission behaviour of the bales was recorded during experimental periods up to 55 days. The results allow a differentiation of the outgassing processes. On the one hand, gases produced during the anaerobic ensiling process (CO2, CH4, N2O) are released once in a large amount during the first experimental hours after opening the silage. On the other hand, a continuous outgassing process takes place, which is particularly true for the VOCs ethanol, methanol, and ethyl acetate, whereby VOC emissions increase with rising ambient air temperatures. In this study, the emissions during the first 600 experimental hours from the grass silage bale and lucerne silage bale were 2313 g and 2612 g CO2, 17.6 g and 145.2 g methanol, 132.3 g and 675.9 g ethanol, 55.1 g and 66.2 g ethyl acetate, respectively. Nevertheless, the focus of this study was on the technical recording of gas concentrations inside the silage bale itself and the emissions in the ambient air of the bale. For a better interpretation of the data, additional factors should be considered in further investigations.

Objective:To develop a greenhouse gas emissions (GHGE) database for Japanese foods using three different approaches, compare the results of estimated diet-related GHGE and determine major food contributors among Japanese adults.Design:Cross-sectional. Three GHGE databases were developed: (1) a literature-based method including a literature review of life cycle assessment studies of Japanese foods and (2) production- and (3) consumption-based input–output tables (IOT)-applied methods using the Japanese IOT. All databases were linked to the Japanese food composition table and food consumption data. Diet-related GHGE was estimated based on each database and the 4-d dietary record data. Diet-related GHGE were compared in both total and food group level between the databases.Setting:Japan.Participants:392 healthy adults aged 20–69 years.Results:The mean diet-related GHGE significantly differed according to the calculation methods: 4145 g CO2-equivalent (CO2-eq)/d by the literature-based method, 4031 g CO2-eq/d by the production-based method and 7392 g CO2-eq/d by the consumption-based IOT-applied methods. It significantly differed in food group level as well. Spearman’s correlation coefficients between three methods ranged from 0·82 to 0·86. Irrespective of the methods, the top contributor to GHGE was meat (19·7–28·8 %) followed by fish and seafood (13·8–18·3 %).Conclusions:Although the identified major food contributors to GHGE were comparable between the three methods, the estimated GHGE values significantly differed by calculation methods. This finding suggested that caution must be taken when interpreting the estimated diet-related GHGE values obtained using the different calculation methods of GHGE.

A novel integrated microalgae and activated sludge (MA/AS) system was constructed to minimize greenhouse gas emission from traditional wastewater treatment plants. Its removal properties for aqueous pollutants were assessed as well. The ratio of microalgae-to-activated sludge volatile suspended solids of 1.3 and an incident light intensity of 12 W/m2 provided the best performance: COD, NH4+, and total phosphorus (TP) removals were up to 100%, 99.6% and 100%, respectively. Even without illumination, COD, NH4+, and TP removal efficiencies were as high as 95.1%, 96.5% and 100%, respectively. In both cases, nutrient uptake by MA was proved to play an important role in nutrients removal. And no CH4 or N2O emissions were detected during the whole experimental period of the MA/AS system (mass ratio of 1.3:1). Only negligible CO2 was detected up to 45 μmol with illumination and 130 μmol without illumination in the headspace of the serum bottles, which merely accounted for 2.0% and 5.8% of the initial total carbon equivalent (glucose serving as organic carbon source). Since photosynthesis by microalgae could provide oxygen to heterotrophs or nitrifying bacteria, extra energy demand (mainly from aeration units) could be greatly cut down, which would heavily reduce the total energy demands and further indirect CO2 emission from wastewater treatment plants. Our integrated system is demonstrated to be a sustainable approach for contaminants removal from aqueous phase, restraining greenhouse gas emission and saving energy consumption contemporaneously.

The effectiveness of specific concentrations of bamboo biochar (BB) on nutrient conservation based on gaseous emissions during poultry manure composting was investigated. The results indicate that the total carbon and nitrogen losses were significantly reduced with elevated of biochar from 542.8 to 148.9% and 53.5 to 12.6% (correspondingly with an additive of 0%, 2%, 4%, 6% and 8% to 10% BB dry weight based). The primary contributor was CO2 and NH3 losses (542.3-148.8% and 47.8-10.81%). The enzyme activities related to carbon and nitrogen metabolism indicated a positive and significantly enhanced with high concentration biochar amended composting. Simultaneously, the alteration of total organic carbon and total Kjeldahl nitrogen as well as maturity indexes during ultimate compost also confirmed a high quality product under higher content biochar amended composting. Carbon and nitrogen were best preserved with 10%BB and produced a superior final product. The analysis of a network and heat map illustrated the correlation of gaseous and physicochemical elements as well as enzyme activities, with an intersection of 68.81%.

Handling of digestate produced by anaerobic digestion impacts the environment through emission of greenhouse gases, reactive nitrogen, and phosphorus. Previous life cycle assessments (LCA) evaluating the extraction of nutrients from digestate using struvite precipitation and ammonia stripping did not relate synthetic fertilizer substitution (SFS) to nutrient use efficiency consequences. We applied an expanded LCA to compare the conventional management of 1 m3 of liquid digestate (LD) from food waste against the production and use of digestate biofertilizer (DBF) extracted from LD, accounting for SFS efficacy. Avoidance of CH4, N2O, and NH3 emissions from LD handling and enhanced SFS via more targeted use of nutrients in the versatile DBF product could generate environmental savings of up to 0.129 kg Sb eq, 4.16 kg SO2 eq, 1.22 kg PO4 eq, 33 kg CO2 eq, and 20.6 MJ eq per m3 LD, for abiotic resource depletion, acidification, eutrophication, global warming, and cumulative energy demand burdens, respectively....

Almond hulls and citrus pulp have been fed to dairy cows with variable responses for milk production, but no information exists on their effect on enteric methane emissions. This experiment examined the effects of dietary supplementation with either almond hulls or ensiled citrus pulp on the milk yield, milk composition, and enteric methane emissions of dairy cows. Thirty-two Holstein dairy cows in mid lactation were offered 1 of 3 diets over a 28-d experiment. Twelve cows received a control (CON) diet, 10 cows a diet containing almond hulls (ALH), and 10 cows a diet containing ensiled citrus pulp (CIT). All cows were offered 6.0 kg of dry matter (DM)/d of crushed corn, 2.0 kg of DM/d of cold-pressed canola, and 0.2 kg of DM/d of a mineral mix. In addition, cows fed the CON diet were offered 14.5 kg of DM/d of alfalfa cubes; cows fed the ALH diet were offered 10.5 kg of DM/d of alfalfa cubes and 4.0 kg of DM/d of almond hulls; and cows on the CIT diet were offered 11.5 kg of DM/d of alfalfa cubes and 3.0 kg of DM/d of ensiled citrus pulp. Milk yield was measured daily and milk composition was measured on 4 d of each week. Individual cow methane emissions were measured by a sulfur hexafluoride tracer technique on d 24 to 28 of the experiment. The mean milk yield of cows fed the CON diet (27.4 kg/d) was greater than the mean milk yield of cows fed the ALH diet (24.6 kg/cow per day), whereas the mean milk yield of cows fed the CIT diet (26.2 kg/cow per day) was not different from the mean milk yield from cows fed the other 2 diets. Dietary treatment did not influence the concentrations of milk fat, protein, and lactose or fat yields, but the mean protein yield from cows fed the CON diet (0.87 kg/d) was greater than that from cows fed the ALH diet (0.78 kg/d) but not different to those fed the CIT diet (0.85 kg/d). In general, we found no differences in the proportion of individual fatty acids in milk. The mean pH of ruminal fluid from cows offered the CON diet was not different to the pH in the ruminal fluids of cows offered the ALH or the CIT diets. The mean methane emissions (g/d) and yields (g/kg of DM intake) were not influenced by dietary treatment. These findings indicate that, although almond hulls and ensiled citrus pulp can be used as a low-cost feed supplement, almond hulls did negatively affect milk production and neither inhibited enteric methane emissions.

Composting is recognised a promising technology for recycling and adding value to agro-food wastes. There are, however, potential environmental risks associated with composting, such as the emission of greenhouse gases (GHGs). The aim of this study was to quantify the emissions of carbon dioxide, methane, nitrous oxide, nitric oxide and ammonia during composting of five agro-food wastes originated from the broccoli, chestnut, olive and grape industries, and to study the relationship between the emissions and the lignin, cellulose, hemicellulose and phenolic contents of the wastes. According to physicochemical indicators monitored during the process, all agro-food residues tested were suitable for composting, with chestnut in the top and broccoli in the bottom of the range. Composting of chestnut and olive led to higher carbon dioxide, methane and nitrous oxide emissions, whereas lower emissions were observed with white grape. A positive correlation was found between phenolics and nitric oxide (r = 0.63; p < 0.01), but not with the other gases. Lignocellulose showed a positive correlation with nitrous oxide (r = 0.51; p < 0.05), but not with carbon dioxide and methane. The accumulation of lignin was highest in the chestnut compost, which was associated with lower nitric oxide and ammonia emissions relative to the other waste materials. The results show that wastes with high lignocellulose can be managed using composting with additional benefits on the environment in relation to mitigating nitrogen losses. info:eu-repo/semantics/publishedVersion

Open anaerobic lagoons are widely used for liquid manure storage and treatment, with excess greenhouse gas (GHG) and odor emissions. In this study, liquid manure was valorized through hybrid nitrogen and phosphorous recovery as value-added products using an airlift reactor. Also, the organic load of liquid manure was reduced before discharging into anaerobic lagoons, which simultaneously mitigated GHG emissions. The results showed that 14.5% of total nitrogen (TN) was recovered as ammonium sulfate, while 38.8% of TN and 79.3% of total phosphorus (TP) were recovered as phosphorus-rich sludge. After the pre-treatment in the reactor, the odor could be controlled effectively due to a 94.2% decrease in total VFAs. In addition, 59.0% of COD was removed, which decreased the theoretical modeled GHG emissions by 51.7% compared to the traditional direct discharging. The application is promising for upgrading anaerobic lagoons of liquid manure.

Milk production has been estimated to contribute 3-4% of anthropogenic greenhouse gas (GHG) emissions. However, the carbon footprint associated with raw milk can vary, depending on a variety of factors, such as the geographical area, species of cow and production system. In this study, a global overview of research published on the carbon footprint (CF) of raw cow milk is provided. Additionally, two different dairy systems (semi-confinement and pasture-based) have been analysed by life-cycle assessment (LCA) in order to determine their effect on the CF of the milk produced. Inventory data were obtained directly from these facilities, and the main factors involved in milk production were included (co-products, livestock food, water, electricity, diesel, cleaning elements, transport, manure and slurry management, gas emissions to air etc.). In agreement with reviewed literature, it was found that the carbon footprint of milk was basically determined by the cattle feeding system and gas emissions from the cows. The values of milk CF found in the systems under study were within the range for cow milk production worldwide (0.9-4.7 kgCO2eq kgFPCM-1). Specifically, in the semi-confinement and the pasture-based dairy farms, 1.22 and 0.99 kgCO2eq kgFPCM-1 were obtained, respectively. The environmental benefits obtained with the pasture grazing system are not only mainly due to the lower use of purchased fodder but also to the allocation between milk and meat that was found to be a determining methodological factor in CF calculation. Finally, data from the evaluated dairy systems have been employed to analyse the influence of raw milk production on cheese manufacturing. With this aim, the CF of a small-scale cheese factory has also been obtained. The main subsystems involved (raw materials, water, electricity, energy, cleaning products, packaging materials, transport, wastes and gas emissions) were included in the inventory of the cheese factory. CF values were 16.6 and 14.7 kgCO2eq kg-1 of cheese for milk produced in semi-confinement and pasture-based systems, respectively. The production of raw milk represented more than 60% of CO2eq emissions associated with cheese, so the primary production is the critical factor in reducing the GHG emissions due to cheese making.

Meat production and consumption contribute significantly to environmental impacts such as greenhouse gas (GHG) emissions. These emissions can be reduced via various strategies ranging from production efficiency improvement to process optimization, food waste reduction, trade pattern change, and diet structure change. On the basis of a material flow analysis approach, we mapped the dry matter mass and energy balance of the meat (including beef, pork, and poultry) supply chain in Germany and discussed the emission reduction potential of different mitigation strategies in an integrated and mass-balance consistent framework. Our results reaffirmed the low energy conversion efficiency of the meat supply chain (among which beef was the least efficient) and the high GHG emissions at the meat production stage. While diet structure change (either reducing the meat consumption or substituting meat by edible offal) showed the highest emissions reduction potential, eliminating meat waste in retailing and consumption and byproducts generation in slaughtering and processing were found to have profound effect on emissions reduction as well. The rendering of meat byproducts and waste treatment were modeled in detail, adding up to a net environmental benefit of about 5% of the entire supply chain GHG emissions. The combined effects based on assumed high levels of changes of important mitigation strategies, in a rank order considering the level of difficulty of implementation, showed that the total emission could be reduced by 43% comparing to the current level, implying a tremendous opportunity for sustainably feeding the planet by 2050.

In order to investigate the improvement of Diatomite (DM) on the production of cleaner composting, reflected by emission of NH3 and greenhouse gases (GHGs), three dosages of DM (0%, 5% and 10%) were added into mixture of pig manure and sawdust for 42 days composting. Addition of DM promoted the transformation of organic matter and improved the quality of end product. Meanwhile, it was confirmed by the increase of NO3−-N formation and nitrogen conservation. Besides, adding DM aided on reducing emission of CH4, N2O and NH3 by 18.27%−30.41%, 26.89%−84.16% and 10.41%−23.70%, respectively. Furthermore, the DM had a positive effect on the maturity of compost products, reflecting by GI value and HA/FA. Consequently, through the factor analysis, 10% was suggested to improve the quality of end product and reduce nitrogen loss as well as GHGs emission.

ObjectiveTo model dietary changes required to shift the UK population to diets that meet dietary recommendations for health, have lower greenhouse gas emissions (GHGE) and are affordable for different income groups.DesignLinear programming was used to create diets that meet dietary requirements for health and reduced GHGE (57 and 80 % targets) by income quintile, taking account of food budgets and foods currently purchased, thereby keeping dietary change to a minimum.Setting/ParticipantsNutrient composition, GHGE and price data were mapped to 101 food groups in household food purchase data (UK Living Cost and Food Survey (2013), 5144 households).ResultsCurrent diets of all income quintiles had similar total GHGE, but the source of GHGE differed by types of meat and amount of fruit and vegetables. It was possible to create diets with a 57 % reduction in GHGE that met dietary and cost restraints in all income groups. In the optimised diets, the food sources of GHGE differed by income group due to the cost and keeping the level of deviation from current diets to a minimum. Broadly, the changes needed were similar across all groups; reducing animal-based products and increasing plant-based foods but varied by specific foods.ConclusionsHealthy and lower-GHGE diets could be created in all income quintiles but tailoring changes to income groups to minimise deviation may make dietary changes more achievable. Specific attention must be given to make interventions and policies appropriate for all income groups.

Fly larvae composting is an emerging waste treatment alternative with great potential to increase revenue from food waste management. For wider implementation, fly larvae composting has to be evaluated in comparison with conventional systems, based on direct greenhouse gas (GHG) emission data for the treatment process, which are currently limited. This study evaluated direct emissions of CO2, CH4, N2O and NH3 from composting of food waste using black soldier fly (BSF) larvae (Hermetia illucens). Use of BSF larvae-associated bacteria in 7-day pre-treatment and seeding at larvae treatment start were evaluated and compared to larvae treatment without bacteria addition. The treatments were performed in a set of 14-day laboratory-scale experiments. Mean substrate reduction was 49 ± 8% and bioconversion ratio was 24 ± 8% (both dry matter basis). Direct GHG emissions from the fly larvae treatment process were generally very small, with emissions of CH4 and N2O equivalent to 0.38 kg CO2-equivalents per ton food waste treated assuming global warming potential over 100 years, while mean total CO2 emissions were 96 g CO2 per kg food waste treated. Additional emissions could be expected to occur in the pre-treatment process, which did not provide any significant improvement in bioconversion ratio or reduction in total GHG emissions during treatment. Similarly, use of BSF larvae-associated bacteria did not significantly improve process efficiency. No NH3 emissions were detected, as reflected in total N mass balance over the treatment cycle. The results show that total direct GHG emissions from food waste treatment by fly larvae composting are lower than those from conventional food waste treatment, and that pre-treatment and seeding of food waste with BSF larvae-associated bacteria do not further reduce total GHG emissions.

In the present work, a complete study of the sewage sludge (SS) biodrying technology was conducted at benchscale, aiming at assessing its performance and providing a valuable insight into the different gaseous emission patterns found for greenhouse gases (GHG) and odorant pollutants. As process key parameters, temperature, specific airflow, dynamic respiration index, final moisture content and Lower Calorific Value (LCV) were evaluated. At the end of the biodrying, a product with a 35.9% moisture content and a LCV of 7.1 MJ·kg−1product was obtained. GHGs emission factor was 28.22 kgCO2eq per Mg of initial mass of dry matter in the SS (DM0-SS). During the biodrying process, maximum odour concentration measured was 3043 ou·m−3 and the estimated odour emission factor of the biological treatment was 3.10E+07 ou per Mg DM0-SS. Finally, VOCs were completely identified and quantified. The most abundant VOCs found in the biodrying gaseous emissions were terpenes, sulphur-compounds and ketones. This study was carried out within the framework of the "SMART-Plant" Innovation Action which has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 690323.

The syngas that is produced from waste biomass often has high levels of CH4 and CO2, which are greenhouse gases. This investigation presents an integrated gasification and catalytic reforming process with a closed gas loop that can improve quality of syngas from corn straw and mitigate CH4 and CO2 emission. The effects of the support type, reforming temperature, steam-to-biomass (S/B) ratio, and catalyst-to-biomass ratio (C/B) ratio on gas yield and composition were experimentally examined with waste corn straw as the feedstock gasified at 850 °C in the proposed closed-loop apparatus. Reformation of syngas using Ni/γ-Al2O3 at 850 °C, S/B = 1 and C/B = 0.5 yielded 1.16 m3/kg of syngas, which contained 48.5% H2, 33.9% CO, 12.2% CO2 and 5.3% CH4, corresponding to 71.0% and 81.5% enhancements of the first two and −77.8% and −58.1% reductions of the last two components.

Biogas purification via water scrubbing produces effluent containing dissolved CH4, H2S, and CO2, which should be removed to reduce greenhouse gas emissions and increase its potential for water regeneration. In this study, a reactor built with air supplies at the top and bottom was utilized for the treatment of biogas purification effluent through biological oxidation and physical stripping processes. Up to 98% of CH4 was removed through biological treatment at a hydraulic retention time of 2 hr and an upper airflow rate of 2.02 L/day. Additionally, a minimum CH4 concentration of 0.04% with no trace of H2S gas was detected in the off gas. Meanwhile, a white precipitate was captured on the carrier showing the formation of sulfur. According to the developed mathematical model, an upper airflow rate of greater than 2.02 L/day showed a small deterioration in CH4 removal performance after reaching the maximum value, whereas a 50 L/day bottom airflow rate was required to strip the CO2 efficiently and raise the effluent pH from 5.64 to 7.3. Microbiological analysis confirmed the presence of type 1 methanotroph communities dominated by Methylobacter and Methylocaldum. However, bacterial communities promoting sulfide oxidation were dominated by Hyphomicrobium.

The long maturation period and greenhouse gas (GHG) emission are two major problems that arise during aerobic composting, mainly due to the low efficiency of O2 transmission and utilization. In this study, a novel electric-field-assisted aerobic composting (EAC) process was tested by simply applying a direct-current voltage of 2 V to a conventional aerobic composting (CAC) process. Compared with the CAC process, the maturation time and the total GHG for the EAC process were reduced by 33% and 70%, respectively. Furthermore, the analyses of O2 consumption and microbial communities demonstrated that the electric field had enhanced O2 utilization by 30 ± 9% and increased the relative abundance of electroactive bacteria by about 3.4-fold compared to CAC. This work has represented a proof of principle for EAC and suggests that the electric field is an effective and environmentally friendly strategy for enhancing compost maturity and mitigating GHG emissions during aerobic composting.

Biochar produced from pyrolysis of biomass is a candidate with great potential for climate change mitigation by carbon sequestration and reduction of greenhouse gases (GHG) emission in soil. Its potential depends considerably on biochar properties. Biochar stability or biochar C recalcitrance is decisive to its carbon storage/sequestration potential in soil. Three groups of methods including: I) biochar C structure or composition analyses, II) biochar oxidation resistance determination, and III) biochar persistence assessment by incubation & modelling, have been developed for evaluation of biochar stability. Amongst, incubation & modelling is the most commonly used one and is the basis of the other two assessment methods. However, the strategies for incubation experiment designing and data modelling significantly influence the biochar stability results. Drastic differences were observed for stability results obtained from different studies partly because of the large flexibility of the incubation & modelling method. Biased biochar stability would be obtained if the method was used improperly. The present review aims to provide comprehensive information on method strategies used for incubation and modelling, followed by discussions on the key issues such as what kind of biochar to use, how the experiment should be designed, how to determine biochar C mineralization, how the mineralization data should be expressed, and what model should be used, for an accurate biochar stability evaluation. In general, incubating biochar at long-term duration, modelling incubation data with double-exponential model, using C isotopic technology for CO2 evolution determination with C mineralization data express as percentage of total organic carbon mineralized, applying biochar in the field are favorable to biochar stability assessment. Other strategies such as the use of standard (reference) biochar materials may be effective to improve the assessment.

The agricultural industry is the main emitter of methane (CH4) and nitrous oxide (N2O), gases that each have a global warming potential that is greater than that of CO2 by 23 and 298 times, respectively. On a global scale, enteric fermentation from ruminant animal production (especially of cattle and sheep) is responsible for between 21% and 25% of total anthropogenic CH4 emissions. The search for effective, simple, and fast methods to measure the production of CH4 and other products from ruminal fermentation has been the objective of several studies on ruminant nutrition. Thus, techniques have been developed under experimental conditions of Brazil and other international countries to quantify CH4 emissions of ruminants. The objective of this literature review is to discuss and compare the existing techniques of measuring enteric CH4 from ruminants. Each technique has a shortcoming or disadvantage in its characterization of ruminal fermentation. The ex-situ technique of measuring CH4 from ruminal fermentation has been quite promising, because it facilitates the measurement of CH4 and other fermentation products, such as short chain fatty acids (SOFA). CH4 detection by a portable laser is effective in monitoring fluctuations in emission and is recommended especially for short-term measurements of respiring and eructating animals reared in a feedlot system. Other methods are being improved and better adapted for practical use in the ongoing quest for more efficient uses of ruminal fermentation products. La industria pecuaria es el principal emisor de metano (CH4) y óxido nitroso (N2O) para la atmósfera, eses gases tienen un potencial de calentamiento global, respectivamente, 23 y 298 veces mayor que el CO2. La fermentación entérica y particularmente en animales rumiantes (principalmente ganado vacuno y ovino) producen, en una escala global, entre el 21 y el 25% de las emisiones antropogénicas de CH4. La demanda de métodos precisos, sencillos y rápidos para medir la producción de metano y otros productos de la fermentación ruminal ha sido objeto de investigación en nutrición de rumiantes. Por lo tanto, se desarrollaron técnicas para cuantificar la emisión de metano por los rumiantes, brasileños y extranjeros bajo diferentes condiciones experimentales. Esta revisión de literatura destinada a discutir haciendo una comparación entre las metodologías existentes para la medición de metano entérico en rumiantes. Por lo tanto, se entiende que cada método ha desarrollado algunos insuficiencia o molestias cuando se pretende caracterizar la fermentación ruminal. La técnica de medición de la fermentación ruminal ex-situ de metano ha sido bastante prometedora, ya que permite medir la producción de CH4 y otros productos de fermentación tales como ácidos grasos de cadena corta. Láser portátil detector de metano es eficaz cuando se cruza la información de los picos de metano en eructos y la respiración y se recomienda para mediciones cortas, sobre todo para los animales en el sistema feedlot. Sin embargo, algunas metodologías se están mejorando y satisfaciendo en busca de mejores resultados en productos de la fermentación ruminal. O setor pecuário é o principal emissor de metano (CH4) e óxido nitroso (N2O) para a atmosfera, gases com potencial de aquecimento global, respectivamente, 23 e 298 vezes maior que o CO2. Particularmente a fermentação entérica em animais ruminantes (predominantemente bovinos e ovinos) produz, em escala global, entre 21 e 25% do total das emissões antropogênicas de metano. A procura por métodos acurados, simples e rápidos para mensurar a produção de metano e outros produtos da fermentação ruminal tem sido objetivo de pesquisas na nutrição de ruminantes. Desta forma, técnicas foram desenvolvidas com o objetivo de quantificar-se a emissão de metano por ruminantes, sob diferentes condições experimentais brasileiras e estrangeiras. Esta revisão de literatura teve como objetivo discutir, fazendo um comparativo entre as metodologias existentes para mensuração do metano entérico em ruminantes. Desta forma, entende-se que cada método desenvolvido possui alguma inadequação ou inconveniente quando se objetiva a caracterização da fermentação ruminal. A técnica de fermentação ruminal ex-situ de mensuração de metano tem se mostrado bastante promissora, pois permite mensurar a produção de CH4 e outros produtos da fermentação como os ácidos graxos de cadeia curta. O detector de metano a laser portátil é eficiente ao cruzar as informações dos picos de metano na eructação e respiração e recomendado para mensurações curtas, especialmente para animais em sistema de fedlot. Entretanto algumas metodologias estão sendo aprimoradas e adequando-se em busca de melhores resultados sobre os produtos da fermentação ruminal.

This study was evaluated industrial waste fine coal gasification slag (FCGS) as an additive on pig manure composting by parameters of greenhouse gases, NH3, volatile fatty acids (VFAs) and maturity. Six treatments of FCGS (0%, 2%, 4%, 6%, 8% and 10%) were added into the mixture raw material and composted 42 days. Results illustrated that the FCGS amendment could prolong sanitation stage and promote the degree of maturity, germination index and C/N ratio during composting. With the increasing amendment of FCGS, GI was increased from 9.97 to 28.45%. Compared with control, increasing of FCGS proportion could reduce the mitigation of global warming potential (N2O and CH4), NH3 and cumulative of VFAs from 8.89–77.04%, 3.81–71.65%, 5.18–28.02% and 8.79–83.33%. Finally, present study results revealed that 10%FCGS could improve composting and reduced the maturity period as well as compost quality, thus recommended as effective dosage for efficient pig manure composting.