Influence of Aeration on NH3, CH4 and N2O Emissions during Kitchen Waste Composting

Because of high moisture content and compact structure, composting kitchen waste would discharge by-products such as leachate, ammonia (NH3), and greenhouse gases, and these can cause secondary environmental pollution. In this study, continuous measurements of gas emissions were carried out and detailed gas emission patterns were obtained using forced aeration system at aerations of 2·10-4 (T1), 4·10-4 (A2) and 6·10-4 ( (A3) m3·kgDM-1·min-1. During the experiment, temperature and oxygen content were determined, and continuous measurements of NH3 and gaseous emissions (CH4, N2O, and NH3) were taken. The results indicated that the aeration had a significant effect on NH3, CH4 and N2O emission (p<0.05). The highest concentration of NH3, CH4 and N2O were all observed in the treatment of T2. The productions of NH3 were reduced by 59.6% and 33.7%, and greenhouse gases (GHG) were reduced by 50.8% and 40.5% for T1 and T2 that compared to T3, respectively. Obviously, the aeration has great influence on NH3 and GHG emissions. In this study, the aeration was 2·10-4 m3·kgDM-1·min-1 in favor of NH3 and GHG reduction.

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Rare Earth Electrolysis: key issues for measurement of greenhouse gases from oxide-fluoride systems

10.21203/rs.3.rs-839313/v1 ◽

2021 ◽

Author(s):

Sandra Harumi Harumi Fukurozaki ◽

Fernando José Gomes Landgraf

Keyword(s):

Rare Earth ◽

Greenhouse Gases ◽

Environmental Protection Agency ◽

Ghg Emissions ◽

Industrial Process ◽

Metal Production ◽

Ghg Mitigation ◽

Primary Metal ◽

Ghg Reduction ◽

Key Issues

Abstract Over the past decade, the reduction of greenhouse gases (GHG) has been recognized as one of the key factors for sustainable primary metal production, in which the rare earth (RE) industry can be affected both in terms of price and use by GHG reduction policies and nontariff technical barriers. From environmental and economic standpoint, the perfluorocarbons (PFC) emissions generated in RE electrolysis during events known as anode effects (AE) are strong infrared-absorbing GHG and play an important role for RE metals process improvements. However, there is no standard methodology to account these GHG emissions from RE metal production industry and the assessment of the contribution of PFC emissions from different technologies to the global warming is urgently needed. This paper focuses on the analysis of PFC measurements from RE metal production in terms of GHG inventory and sustainable production. The state of art of RE fused oxide-fluoride electrolysis, particularly of neodymium electrolysis, provides the technical fundamentals for the evaluation of PFC emissions factors reported in scientific articles. Based on International Panel on Climate Change (IPCC) standard methods and US Environmental Protection Agency (EPA) and International Aluminium Institute (IAI) protocol applied to analogous industrial process, the analysis of key issues for estimate CF4 and C2F6 emission factors from electrolytic RE production indicates the additional refinements are necessary to optimize the accuracy of total PFC emission amount from each currently RE technology. Additionally, the selection of emission estimation technique (EET) or mix EET should be considered on case-by-case basis as to their purposes and suitability for a particular process and facility. Finally, this paper highlights the technological implications related to the PFC emissions measurements and trends towards to set goals and develop strategies for GHG mitigation.

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Lignite Improved the Quality of Composted Manure and Mitigated Emissions of Ammonia and Greenhouse Gases during Forced Aeration Composting

Sustainability ◽

10.3390/su122410528 ◽

2020 ◽

Vol 12 (24) ◽

pp. 10528

Author(s):

Robert Impraim ◽

Anthony Weatherley ◽

Trevor Coates ◽

Deli Chen ◽

Helen Suter

Keyword(s):

Greenhouse Gases ◽

Ghg Emissions ◽

N2o Emissions ◽

Emission Mitigation ◽

Total N ◽

Compost Stability ◽

Nh3 Emission ◽

Forced Aeration ◽

Carbon Dioxide Co2

Lignite amendment of livestock manure is considered a viable ammonia (NH3) emission mitigation technique. However, its impact on the subsequent composting of the manure has not been well studied. This work compared changes in biochemical parameters (e.g., organic matter loss and nitrogen (N) transformation) and also the emissions of NH3 and greenhouse gases (GHGs) between lignite-amended and unamended cattle manure during forced aeration composting. Amending manure with lignite did not alter the time to compost stability despite delaying the onset of the thermophilic temperatures. Lignite treatments retained N in the manure by suppressing NH3 loss by 35–54%, resulting in lignite-amended manure composts having 10–19% more total N than the unamended compost. Relative to manure only, lignites reduced GHG emissions over the composting period: nitrous oxide (N2O) (58–72%), carbon dioxide (CO2) (12–23%) and methane (CH4) (52–59%). Low levels of CH4 and N2O emissions were observed and this was attributed to the continuous forced aeration system used in the composting. Lignite addition also improved the germination index of the final compost: 90–113% compared to 71% for manure only. These findings suggest that lignite amendment of manure has the potential to improve the quality of the final compost whilst mitigating the environmental release of NH3 and GHGs.

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The potential of agroforestry to reduce atmospheric greenhouse gases in Canada: Insight from pairwise comparisons with traditional agriculture, data gaps and future research

The Forestry Chronicle ◽

10.5558/tfc2017-024 ◽

2017 ◽

Vol 93 (02) ◽

pp. 180-189 ◽

Cited By ~ 11

Author(s):

Mark Baah-Acheamfour ◽

Scott X. Chang ◽

Edward W. Bork ◽

Cameron N. Carlyle

Keyword(s):

Greenhouse Gases ◽

Agricultural Landscape ◽

Ghg Emissions ◽

Agroforestry Systems ◽

Traditional Agriculture ◽

Future Research ◽

Ghg Mitigation ◽

C Stocks ◽

Ghg Reduction ◽

Data Gaps

Canadian agriculture is a source of greenhouse gases (GHG) and agroforestry has the potential to sequester carbon (C), and mitigate agricultural GHG emissions. Agroforestry systems are common features in Canada’s agricultural landscape; however, there are limited empirical data to support implementation of agroforestry practices for GHG mitigation. This shortfall of data may be a contributing factor to the lack of policy that supports the use of agroforestry for GHG mitigation in the Canadian agricultural landscape. We reviewed published studies that compared C stocks in vegetation and soils, and/or GHG emissions in agroforestry systems to traditional agriculture across Canada, with the aims of assessing the benefit of adopting agroforestry for GHG reduction. We then identified data gaps and obstacles that could direct future research. We found that most studies reported increases in vegetation and soil organic C storage in areas with woody species compared to herbaceous crops. Agroforestry systems also reduced the emission of CH4 and N2O, and increased CO2 respiration from soil, but few studies have examined these gases. The small set of studies we reviewed demonstrated the potential of agroforestry to store terrestrial C and mitigate GHG emissions. However, additional research is required to verify this pattern across geographic regions, determine the regional potential for development of agroforestry systems, and assess the potential atmospheric GHG reduction at regional and national scales.

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Rare Earth Electrolysis: key issues for measurement of greenhouse gases from oxide-fluoride systems

10.21203/rs.3.rs-839313/v2 ◽

2021 ◽

Author(s):

Sandra Harumi Harumi Fukurozaki ◽

Fernando José Gomes Landgraf

Keyword(s):

Rare Earth ◽

Greenhouse Gases ◽

Environmental Protection Agency ◽

Ghg Emissions ◽

Industrial Process ◽

Metal Production ◽

Ghg Mitigation ◽

Primary Metal ◽

Ghg Reduction ◽

Key Issues

Abstract Over the past decade, the reduction of greenhouse gases (GHG) has been recognized as one of the key factors for sustainable primary metal production, in which the rare earth (RE) industry can be affected both in terms of price and use by GHG reduction policies and non-tariff technical barriers. From environmental and economic standpoint, the perfluorocarbons (PFC) emissions generated in RE electrolysis during events known as anode effects (AE) are strong infrared-absorbing GHG and play an important role for RE metals process improvements. However, there is no standard methodology to account these GHG emissions from RE metal production industry and the assessment of the contribution of PFC emissions from different technologies to the global warming is urgently needed. This paper focuses on the analysis of PFC measurements from RE metal production in terms of GHG inventory and sustainable production. The state of art of RE fused oxide-fluoride electrolysis, particularly of neodymium electrolysis, provides the technical fundamentals for the evaluation of PFC emissions factors reported in scientific articles. Based on International Panel on Climate Change (IPCC) standard methods and US Environmental Protection Agency (EPA) and International Aluminium Institute (IAI) protocol applied to analogous industrial process, the analysis of key issues for estimate CF4 and C2F6 emission factors from electrolytic RE production indicates the additional refinements are necessary to optimize the accuracy of total PFC emission amount from each currently RE technology. Additionally, the selection of emission estimation technique (EET) or mix EET should be considered on case-by-case basis as to their purposes and suitability for a particular process and facility. Finally, this paper highlights the technological implications related to the PFC emissions measurements and trends towards to set goals and develop strategies for GHG mitigation.

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Environmental Bio Economic Impact in Nicaragua

Journal of Agricultural Studies ◽

10.5296/jas.v1i2.4033 ◽

2013 ◽

Vol 1 (2) ◽

pp. 53

Author(s):

Blanco Orozco ◽

Napoleón Vicente ◽

Zúniga González ◽

Carlos Alberto

Keyword(s):

Greenhouse Gases ◽

Power Plants ◽

Cost Benefit Analysis ◽

Thermal Power ◽

Ghg Emissions ◽

Cost Benefit ◽

Interconnected System ◽

Ghg Reduction ◽

Sugar Mills ◽

The Impact

In this article the Bio economy of power plants connected to the national interconnected system of Nicaragua is analyzed, through the study of environmental effects of greenhouse gases emissions from the use of solid biomass from sugarcane bagasse and oil to generate electricity. In addition, an analysis of Cost - Benefit of investments to the electricity generation using fossil fuel and bagasse is done. The Methodology EX-Ante Carbon-balance Tool (EX-ACT) was used; this methodology was proposed by the United Nations Organization for Food and Agriculture (FAO) to determine the overall greenhouse gases (GHG) emission balance. Additionally, the WinDASI program, also developed by FAO, was used for the Cost - Benefit Analysis of investment in power plants. Furthermore, we performed marginal costing GHG reduction. The results show, that all plants are sources of GHG emissions, however the impact of sugar mills is partially positive by reforestation components and annual crops. However, the component inputs had negative environmental and socially impact. In the case of thermal power generation plants based on petroleum connected to the national grid, they were found to be sources of greenhouse gases. The analysis of the Benefit Cost in their investment indicates that there is a positive financially impact except in ALBANISA power plant and sugar Mills power plants.

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Enhancement of Food Waste Management and Its Environmental Consequences

Energies ◽

10.3390/en14061790 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1790

Author(s):

Jan den Boer ◽

Gudrun Obersteiner ◽

Sebastian Gollnow ◽

Emilia den Boer ◽

Renata Bodnárné Sándor

Keyword(s):

Anaerobic Digestion ◽

Waste Management ◽

Environmental Effects ◽

Ghg Emissions ◽

Primary Energy ◽

Biological Pretreatment ◽

Environmental Benefit ◽

Kitchen Waste ◽

Considerable Saving ◽

Positive Effects

This paper assesses the potential environmental effects of the optimization of the kitchen waste management in Opole. The separate collection of kitchen waste is improved by distribution of separate collection kits consisting of an in-home bin and 10 L biodegradable bags. The surplus of collected kitchen waste is diverted from treatment in a mechanical-biological pretreatment (MBP) along with the residual waste to anaerobic digestion (AD) with the biowaste. This has positive effects on European and Polish goals, ambitions, and targets, such as (i) increasing the level of renewables in the primary energy supply, (ii) decreasing the level of greenhouse gas (GHG) emissions, (iii) increasing the level of preparation for reuse and recycling of municipal waste. The environmental effects of 1 ton additionally separately collected and treated kitchen waste are determined by using life cycle assessment. It was shown that in all selected impact categories (global warming potential, marine eutrophication potential, acidification potential, and ozone depletion potential) a clear environmental benefit can be achieved. These benefits are mainly caused by the avoided emissions of electricity and heat from the Polish production mix, which are substituted by energy generation from biogas combustion. Optimization of the waste management system by diversion of kitchen waste from mechanical-biological pretreatment to anaerobic digestion can lead to considerable saving of 448 kg CO2-eq/t of waste diverted. With an estimated optimization potential for the demonstration site of 40 kg/inh·year for the city of Opole, this would lead to 680,000 t CO2-eq savings per year for the whole of Poland. The sensitivity analysis showed that with a choice for cleaner energy sources the results would, albeit lower, show a significant savings potential.

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The role of the European small ruminant dairy sector in stabilising global temperatures: lessons from GWP* warming-equivalent emission metrics

Journal of Dairy Research ◽

10.1017/s0022029921000157 ◽

2021 ◽

pp. 1-8

Author(s):

Agustin del Prado ◽

Pablo Manzano ◽

Guillermo Pardo

Keyword(s):

Small Ruminant ◽

Ghg Emissions ◽

Small Ruminants ◽

Feed Additives ◽

Dairy Goat ◽

Emission Rates ◽

Animal Products ◽

Ghg Reduction ◽

Mitigate Climate Change ◽

Climate Neutrality

Abstract Recent calls advocate that a huge reduction in the consumption of animal products (including dairy) is essential to mitigate climate change and stabilise global warming below the 1.5 and 2°C targets. The Paris Agreement states that to stabilise temperatures we must reach a balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases (GHG) in the second half of this century. Consequently, many countries have adopted overall GHG reduction targets (e.g. EU, at least 40% by 2030 compared to 1990). However, using conventional metric-equivalent emissions (CO2-e GWP100) as the basis to account for emissions does not result in capturing the effect on atmospheric warming of changing emission rates from short-lived GHG (e.g. methane: CH4), which are the main source of GHG emissions by small ruminants. This shortcoming could be solved by using warming-equivalent emissions (CO2-we, GWP*), which can accurately link annual GHG emission rates to its warming effect in the atmosphere. In our study, using this GWP* methodology and different modelling approaches, we first examined the historical (1990–2018) contribution of European dairy small ruminant systems to additional atmosphere warming levels and then studied different emission target scenarios for 2100. These scenarios allow us to envision the necessary reduction of GHG emissions from Europe's dairy small ruminants to achieve a stable impact on global temperatures, i.e. to be climatically neutral. Our analysis showed that, using this type of approach, the whole European sheep and goat dairy sector seems not to have contributed to additional warming in the period 1990–2018. Considering each subsector separately, increases in dairy goat production has led to some level of additional warming into the atmosphere, but these have been compensated by larger emission reductions in the dairy sheep sector. The estimations of warming for future scenarios suggest that to achieve climate neutrality, understood as not adding additional warming to the atmosphere, modest GHG reductions of sheep and goat GHG would be required (e.g. via feed additives). This reduction would be even lower if potential soil organic carbon (SOC) from associated pastures is considered.

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Evaluation of a Novel Poultry Litter Amendment on Greenhouse Gas Emissions

Atmosphere ◽

10.3390/atmos12050563 ◽

2021 ◽

Vol 12 (5) ◽

pp. 563

Author(s):

Kelsey Anderson ◽

Philip A. Moore ◽

Jerry Martin ◽

Amanda J. Ashworth

Keyword(s):

Air Quality ◽

Greenhouse Gas ◽

Co2 Emissions ◽

Management Practices ◽

Block Design ◽

Poultry Litter ◽

Ghg Emissions ◽

Nitrous Oxide Emissions ◽

Gaseous Emissions ◽

Poultry Facilities

Gaseous emissions from poultry litter causes production problems for producers as well as the environment, by contributing to climate change and reducing air quality. Novel methods of reducing ammonia (NH3) and greenhouse gas (GHG) emissions in poultry facilities are needed. As such, our research evaluated GHG emissions over a 42 d period. Three separate flocks of 1000 broilers were used for this study. The first flock was used only to produce litter needed for the experiment. The second and third flocks were allocated to 20 pens in a randomized block design with four replicated of five treatments. The management practices studied included an unamended control; a conventional practice of incorporating aluminum sulfate (referred to as alum) at 98 kg/100 m2); a novel litter amendment made from alum mud, bauxite, and sulfuric acid (alum mud litter amendment, AMLA) applied at different rates (49 and 98 kg/100 m2) and methods (surface applied or incorporated). Nitrous oxide emissions were low for all treatments in flocks 2 and 3 (0.40 and 0.37 mg m2 hr−1, respectively). The formation of caked litter (due to excessive moisture) during day 35 and 42 caused high variability in CH4 and CO2 emissions. Alum mud litter amendment and alum did not significantly affect GHGs emissions from litter, regardless of the amendment rate or application method. In fact, litter amendments such as alum and AMLA typically lower GHG emissions from poultry facilities by reducing ventilation requirements to maintain air quality in cooler months due to lower NH3 levels, resulting in less propane use and concomitant reductions in CO2 emissions.

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The potential of bio-methane as bio-fuel/bio-energy for reducing greenhouse gas emissions: a qualitative assessment for Europe in a life cycle perspective

Water Science & Technology ◽

10.2166/wst.2008.039 ◽

2008 ◽

Vol 57 (11) ◽

pp. 1683-1692 ◽

Cited By ~ 53

Author(s):

Andrea Tilche ◽

Michele Galatola

Keyword(s):

Wastewater Treatment ◽

Life Cycle ◽

Anaerobic Digestion ◽

Greenhouse Gas ◽

Industrial Wastewater ◽

Ghg Emissions ◽

Energy Crops ◽

Qualitative Assessment ◽

Potential Contribution ◽

Ghg Reduction

Anaerobic digestion is a well known process that (while still capable of showing new features) has experienced several waves of technological development. It was “born” as a wastewater treatment system, in the 1970s showed promise as an alternative energy source (in particular from animal waste), in the 1980s and later it became a standard for treating organic-matter-rich industrial wastewater, and more recently returned to the market for its energy recovery potential, making use of different biomasses, including energy crops. With the growing concern around global warming, this paper looks at the potential of anaerobic digestion in terms of reduction of greenhouse gas (GHG) emissions. The potential contribution of anaerobic digestion to GHG reduction has been computed for the 27 EU countries on the basis of their 2005 Kyoto declarations and using life cycle data. The theoretical potential contribution of anaerobic digestion to Kyoto and EU post-Kyoto targets has been calculated. Two different possible biogas applications have been considered: electricity production from manure waste, and upgraded methane production for light goods vehicles (from landfill biogas and municipal and industrial wastewater treatment sludges). The useful heat that can be produced as by-product from biogas conversion into electricity has not been taken into consideration, as its real exploitation depends on local conditions. Moreover the amount of biogas already produced via dedicated anaerobic digestion processes has also not been included in the calculations. Therefore the overall gains achievable would be even higher than those reported here. This exercise shows that biogas may considerably contribute to GHG emission reductions in particular if used as a biofuel. Results also show that its use as a biofuel may allow for true negative GHG emissions, showing a net advantage with respect to other biofuels. Considering also energy crops that will become available in the next few years as a result of Common Agricultural Policy (CAP) reform, this study shows that biogas has the potential of covering almost 50% of the 2020 biofuel target of 10% of all automotive transport fuels, without implying a change in land use. Moreover, considering the achievable GHG reductions, a very large carbon emission trading “value” could support the investment needs. However, those results were obtained through a “qualitative” assessment. In order to produce robust data for decision makers, a quantitative sustainability assessment should be carried out, integrating different methodologies within a life cycle framework. The identification of the most appropriate policy for promoting the best set of options is then discussed.

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