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1.
Proc Natl Acad Sci U S A ; 119(11): e2200997119, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35263229
2.
J Public Health Manag Pract ; 24 Suppl 2: S28-S35, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29369254

Resumo

CONTEXT: The use of biogas systems to treat livestock waste is a common practice in Vietnam. However, farmers' knowledge and practices of the safe and appropriate use of household biogas units (HBUs) are still limited and could negatively impact human, animal, and environmental health. OBJECTIVE: To assess the effectiveness of an intervention to improve knowledge and practices of biogas operation among farmers in 2 communes of Ha Nam Province, Vietnam. DESIGN: A community-based intervention approach. SETTING: This study was conducted from 2015 to 2016 in 2 communes of Ha Nam Province, Vietnam. PARTICIPANTS: Only farmers with HBUs (N = 399) participated in this research. Farmers were assigned to either an intervention group or a control group at a ratio of 1:2. INTERVENTION: Two intervention steps were implemented over a 6-month period as follows: (i) the core farmer group trained in 6 steps of HBU safe handling practice; and (ii) the core farmer group conducted peer-to-peer communication with its neighbors in the commune using the provided material. MAIN OUTCOME MEASURE(S): Farmers' knowledge and practices in biogas operation were assessed by a structured questionnaire. The questionnaire was administered before (baseline) and after the intervention (follow-up) to both the control and intervention groups. RESULTS: There was a significant difference in the knowledge and practices of biogas operation between the 2 groups, in which farmers in the intervention group demonstrated better understanding of the related topic than the control group (P < .05, t test). A linear regression model indicated that baseline and follow-up scores in both knowledge and practices of the intervention group were higher than those of the control group. After the intervention, the mean difference score in knowledge and practices between the intervention and control groups was 5.0 and 2.0 points, respectively (P < .01). CONCLUSION: A community-based intervention approach could be applied to improve knowledge and practices among farmers in using biogas systems. However, further studies should be conducted to assess the sustainability and effectiveness of this model.


Assuntos
Biocombustíveis/efeitos adversos , Culinária/instrumentação , Fazendeiros/psicologia , Conhecimento , Adulto , Biocombustíveis/normas , Participação da Comunidade/métodos , Culinária/métodos , Fazendeiros/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vietnã
3.
Sci Eng Ethics ; 23(2): 509-519, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27168332

Resumo

A new trend in the production technology of solid biof uels has appeared. There is a wide consensus that most solid biofuels will be produced according to the new production methods within a few years. Numerous samples were manufactured from agro-residues according to conventional methods as well as new methods. Robust analyses that reviewed the hygienic, environmental, financial and ethical aspects were performed. The hygienic and environmental aspect was assessed by robust chemical and technical analyses. The financial aspect was assessed by energy cost breakdown. The ethical point of view was built on the above stated findings, the survey questionnaire and critical discussion with the literature. It is concluded that the new production methods are significantly favourable from both the hygienic and environmental points of view. Financial indicators do not allow the expressing of any preference. Regarding the ethical aspect, it is concluded that the new methods are beneficial in terms of environmental responsibility. However, it showed that most of the customers that took part in the survey are price oriented and therefore they tend to prefer the cheaper-conventional alternative. In the long term it can be assumed that expansion of the new technology and competition among manufacturers will reduce the costs.


Assuntos
Biocombustíveis , Ética , Biocombustíveis/economia , Biocombustíveis/normas , Economia , Meio Ambiente , Inquéritos e Questionários
4.
Soc Stud Sci ; 47(1): 7-32, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28195029

Resumo

While there is ample scholarly work on regulatory science within the state, or single-sited global institutions, there is less on its operation within complex modes of global governance that are decentered, overlapping, multi-sectorial and multi-leveled. Using a co-productionist framework, this study identifies 'epistemic jurisdiction' - the power to produce or warrant technical knowledge for a given political community, topical arena or geographical territory - as a central problem for regulatory science in complex governance. We explore these dynamics in the arena of global sustainability standards for biofuels. We select three institutional fora as sites of inquiry: the European Union's Renewable Energy Directive, the Roundtable on Sustainable Biomaterials, and the International Organization for Standardization. These cases allow us to analyze how the co-production of sustainability science responds to problems of epistemic jurisdiction in the global regulatory order. First, different problems of epistemic jurisdiction beset different standard-setting bodies, and these problems shape both the content of regulatory science and the procedures designed to make it authoritative. Second, in order to produce global regulatory science, technical bodies must manage an array of conflicting imperatives - including scientific virtue, due process and the need to recruit adoptees to perpetuate the standard. At different levels of governance, standard drafters struggle to balance loyalties to country, to company or constituency and to the larger project of internationalization. Confronted with these sometimes conflicting pressures, actors across the standards system quite self-consciously maneuver to build or retain authority for their forum through a combination of scientific adjustment and political negotiation. Third, the evidentiary demands of regulatory science in global administrative spaces are deeply affected by 1) a market for standards, in which firms and states can choose the cheapest sustainability certification, and 2) the international trade regime, in which the long shadow of WTO law exerts a powerful disciplining function.


Assuntos
Biocombustíveis/normas , Regulamentação Governamental , Cooperação Internacional , União Europeia , Organizações
5.
Ecotoxicol Environ Saf ; 134(Pt 2): 455-461, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26849952

Resumo

This paper deals with emission quality of diesel engine based on eco toxicological studies with different methods of environmental standard toxicity tests satisfy the Bharath and European emission norms. Based on the emission norms, Corn Oil Methyl Ester (COME) with diesel is tested in a compression ignition engine and the performance and combustion characteristics are discussed. The corn oil was esterified and the property of corn oil methyl ester was within the limits specified in ASTM D 6751-03. The COME was blended together with diesel in different proportion percentages along with B20, B40, B60, B80, and B100. The emission and performance tests for various blends of COME was carried out using single cylinder, four stroke diesel engine, and compared with the performance obtained with 100% diesel (D100). The results give clear information that COME has low exhaust emissions and increase in performance compared to D100 without any modifications. It gives better performance, which is nearer to the obtained results of D100. Specific Fuel Consumption (SFC) of B100 at the full load condition is found to be 4% lower than that of (D100). The maximum Brake Thermal Efficiency (BTE) of B100 is found to be 8.5% higher than that of the D100 at full load. Also, the maximum BTE of part load for different blends is varied from 5.9% to 7.45% which is higher than D100. The exhaust gas emissions like Carbon Monoxide (CO), Carbon Dioxide (CO2), Hydro Carbon (HC) and Nitrogen Oxide (NOx) are found to be 2.3 to 18.8% lower compared to D100 for part as well as full load. The heat release rate of biodiesel and it blends are found to 16% to 35% lower as compared to D100 for part load, where as for full load it is 21% lower than D100. The results showed that the test of emissions norms are well within the limits of Bharath VI and European VI and it leads to less pollution, less effect on green eco system and potential substitute to fossil fuels.


Assuntos
Biocombustíveis/análise , Óleo de Milho , Meio Ambiente , Emissões de Veículos , Zea mays , Biocombustíveis/normas , Carbono/análise , Dióxido de Carbono/análise , Monóxido de Carbono/análise , Ésteres , Gasolina/análise , Óxido Nítrico/análise , Óxidos de Nitrogênio/análise
6.
Environ Sci Technol ; 49(1): 93-102, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25478782

Resumo

The narrow scope of the U.S. renewable fuel standard (RFS2) is a missed opportunity to spur a wider range of biomass use. This is especially relevant as RFS2 targets are being missed due to demand-side limitations for ethanol consumption. This paper examines the greenhouse gas (GHG) implications of a more flexible policy based on RFS2, which includes credits for chemical use of bioethanol (to produce bioethylene). A Monte Carlo simulation is employed to estimate the life-cycle GHG emissions of conventional low-density polyethylene (LDPE), made from natural gas derived ethane (mean: 1.8 kg CO2e/kg LDPE). The life-cycle GHG emissions from bioethanol and bio-LDPE are examined for three biomass feedstocks: U.S. corn (mean: 97g CO2e/MJ and 2.6 kg CO2e/kg LDPE), U.S. switchgrass (mean: -18g CO2e/MJ and -2.9 kg CO2e/kg LDPE), and Brazilian sugar cane (mean: 33g CO2e/MJ and -1.3 kg CO2e/kg LDPE); bioproduct and fossil-product emissions are compared. Results suggest that neither corn product (bioethanol or bio-LDPE) can meet regulatory GHG targets, while switchgrass and sugar cane ethanol and bio-LDPE likely do. For U.S. production, bioethanol achieves slightly greater GHG reductions than bio-LDPE. For imported Brazilian products, bio-LDPE achieves greater GHG reductions than bioethanol. An expanded policy that includes bio-LDPE provides added flexibility without compromising GHG targets.


Assuntos
Poluição do Ar/estatística & dados numéricos , Biocombustíveis/normas , Efeito Estufa , Polietileno/síntese química , Energia Renovável/normas , Biocombustíveis/economia , Biocombustíveis/estatística & dados numéricos , Biomassa , Etanol , Método de Monte Carlo , Gás Natural , Panicum , Polietileno/economia , Saccharum , Estados Unidos , Zea mays
7.
Ecotoxicol Environ Saf ; 121: 253-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25838071

Resumo

Lipid from microalgae is one of the putative oil resources to facilitate the biodiesel production during this era of energy dissipation and environmental pollution. In this study, the key parameters such as biomass productivity, lipid productivity and lipid content were evaluated at the early stationary phase of Chlamydomonas reinhardtii, CC1010 cultivated in nutrient starved (nitrogen, phosphorous), glucose (0.05%, 0.1%, 0.15% and 0.2%) and vitamin B12 supplementation (0.001%, 0.002% and 0.003%) in Tris-Acetate-Phosphate (TAP) medium. The lipid content in nitrogen starved media was 61% which is 2.34 folds higher than nutrient sufficient TAP medium. Glucose supplementation has lead to proportional increase in biomass productivity with the increasing concentration of glucose whereas vitamin B12 supplementations had not shown any influence in lipid and biomass production. Further, fatty acid methyl ester (FAME) profiling of C. reinhardtii, CC 1010 has revealed more than 80% of total SFA (saturated fatty acid) and MUFA (mono unsaturated fatty acid) content. Quality checking parameters of biodiesel like cetane number, saponification value, iodine number and degree of unsaturation were analyzed and the biodiesel fuel properties were found to be appropriate as per the international standards, EN 14214 and ASTM D6751. Conclusively, among all the treatments, nitrogen starvation with 0.1% glucose supplementation had yielded high lipid content in C. reinhardtii, CC 1010.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Chlamydomonas reinhardtii/crescimento & desenvolvimento , Chlamydomonas reinhardtii/metabolismo , Ácidos Graxos/biossíntese , Biocombustíveis/normas , Biomassa , Ácidos Graxos/análise , Cromatografia Gasosa-Espectrometria de Massas , Glucose/metabolismo , Lipídeos/análise , Lipídeos/biossíntese , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Microscopia Confocal , Nitrogênio/metabolismo , Fósforo/metabolismo
8.
Environ Sci Technol ; 48(1): 573-81, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24298934

Resumo

The potential of a pilot high rate algal pond (HRAP) interconnected via liquid recirculation with an external absorption column for the simultaneous removal of H2S and CO2 from biogas using an alkaliphilic microalgal-bacterial consortium was evaluated. A bubble column was preferred as external absorption unit to a packed bed column based on its ease of operation, despite showing a comparable CO2 mass transfer capacity. When the combined HRAP-bubble column system was operated under continuous mode with mineral salt medium at a biogas residence time of 30 min in the absorption column, the system removed 100% of the H2S (up to 5000 ppmv) and 90% of the CO2 supplied, with O2 concentrations in the upgraded biogas below 0.2%. The use of diluted centrates as a free nutrient source resulted in a gradual decrease in CO2 removal to steady values of 40%, while H2S removal remained at 100%. The anaerobic digestion of the algal-bacterial biomass produced during biogas upgrading resulted in a CH4 yield of 0.21-0.27 L/gVS, which could satisfy up to 60% of the overall energy demand for biogas upgrading. This proof of concept study confirmed that algal-bacterial photobioreactors can support an integral upgrading without biogas contamination, with a net negative CO2 footprint, energy production, and a reduction of the eutrophication potential of the residual anaerobic effluents.


Assuntos
Biocombustíveis/análise , Biotecnologia , Dióxido de Carbono/isolamento & purificação , Sulfeto de Hidrogênio/isolamento & purificação , Microalgas/química , Absorção Fisico-Química , Anaerobiose , Biocombustíveis/normas , Biomassa , Biotecnologia/instrumentação , Biotecnologia/métodos , Microalgas/crescimento & desenvolvimento , Fotobiorreatores , Lagoas/microbiologia , Spirulina/química , Spirulina/crescimento & desenvolvimento
9.
Ann Occup Hyg ; 58(8): 971-82, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25060241

Resumo

The contribution of heavy-duty haulage trucks to the concentrations of aerosols and criteria gases in underground mine air and the physical properties of those aerosols were assessed for three fuel blends made with fatty acid methyl esters biodiesel and petroleum-based ultra-low-sulfur diesel (ULSD). The contributions of blends with 20, 50, and 57% of biodiesel as well as neat ULSD were assessed using a 30-ton truck operated over a simulated production cycle in an isolated zone of an operating underground metal mine. When fueled with the B20 (blend of biodiesel with ULSD with 20% of biodiesel content), B50 (blend of biodiesel with ULSD with 50% of biodiesel content), and B57 (blend of biodiesel with ULSD with 57% of biodiesel content) blends in place of ULSD, the truck's contribution to mass concentrations of elemental and total carbon was reduced by 20, 50, and 61%, respectively. Size distribution measurements showed that the aerosols produced by the engine fueled with these blends were characterized by smaller median electrical mobility diameter and lower peak concentrations than the aerosols produced by the same engine fueled with ULSD. The use of the blends resulted in number concentrations of aerosols that were 13-29% lower than those when ULSD was used. Depending on the content of biodiesel in the blends, the average reductions in the surface area concentrations of aerosol which could be deposited in the alveolar region of the lung (as measured by a nanoparticle surface area monitor) ranged between 6 and 37%. The use of blends also resulted in slight but measurable reductions in CO emissions, as well as an increase in NOX emissions. All of the above changes in concentrations and physical properties were found to be correlated with the proportion of biodiesel in the blends.


Assuntos
Aerossóis/análise , Poluentes Ocupacionais do Ar/análise , Biocombustíveis/análise , Gases/análise , Mineração , Emissões de Veículos/análise , Biocombustíveis/normas , Gasolina , Humanos , Óxidos de Nitrogênio/análise , Exposição Ocupacional/prevenção & controle , Tamanho da Partícula , Material Particulado , Enxofre/análise
10.
Mar Drugs ; 12(6): 3218-30, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24879545

Resumo

The marine oleaginous diatom Fistulifera solaris JPCC DA0580 is a candidate for biodiesel production because of its high lipid productivity. However, the substantial eicosapentaenoic acid (EPA) content in this strain would affect the biodiesel quality. On the other hand, EPA is also known as the essential health supplement for humans. EPAs are mainly incorporated into glycerolipids in the microalgal cell instead of the presence as free fatty acids. Therefore, the understanding of the EPA biosynthesis including the incorporation of the EPA into glycerolipids especially triacylglycerol (TAG) is fundamental for regulating EPA content for different purposes. In this study, in order to identify the biosynthesis pathway for the EPA-containing TAG species, a lipidomic characterization of the EPA-enriched polar lipids was performed by using direct infusion electrospray ionization (ESI)-Q-TRAP-MS and MS/MS analyses. The determination of the fatty acid positional distribution showed that the sn-2 position of all the chloroplast lipids and part of phosphatidylcholine (PC) species was occupied by C16 fatty acids. This result suggested the critical role of the chloroplast on the lipid synthesis in F. solaris. Furthermore, the exclusive presence of C18 fatty acids in PC highly indicated the biosynthesis of EPA on PC. Finally, the PC-based acyl-editing and head group exchange processes were proposed to be essential for the incorporation of EPA into TAG and chloroplast lipids.


Assuntos
Biocombustíveis/normas , Diatomáceas/metabolismo , Ácido Eicosapentaenoico/química , Lipídeos/química , Cloroplastos/metabolismo , Ácido Eicosapentaenoico/biossíntese , Ácidos Graxos/biossíntese , Ácidos Graxos/metabolismo , Lipídeos/biossíntese , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem/métodos , Triglicerídeos/biossíntese , Triglicerídeos/química
11.
Appl Environ Microbiol ; 78(16): 5929-34, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22660702

Resumo

Biodiesel production was examined with Scenedesmus obliquus in a recirculatory aquaculture system with fish pond discharge and poultry litter to couple with waste treatment. Lipid productivity of 14,400 liter ha(-1) year(-1) was projected with 11 cultivation cycles per year. The fuel properties of the biodiesel produced adhered to Indian and international standards.


Assuntos
Biocombustíveis/normas , Scenedesmus/crescimento & desenvolvimento , Scenedesmus/metabolismo , Animais , Aquicultura/métodos , Biocombustíveis/análise , Peixes , Metabolismo dos Lipídeos , Aves Domésticas
12.
Environ Sci Technol ; 46(14): 7849-56, 2012 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-22708628

Resumo

Heavy-metal-polluted biomass derived from phytoremediation or biosorption is widespread and difficult to be disposed of. In this work, simultaneous conversion of the waste woody biomass into bio-oil and recovery of Cu in a fast pyrolysis reactor were investigated. The results show that Cu can effectively catalyze the thermo-decomposition of biomass. Both the yield and high heating value (HHV) of the Cu-polluted fir sawdust biomass (Cu-FSD) derived bio-oil are significantly improved compared with those of the fir sawdust (FSD) derived bio-oil. The results of UV-vis and (1)H NMR spectra of bio-oil indicate pyrolytic lignin is further decomposed into small-molecular aromatic compounds by the catalysis of Cu, which is in agreement with the GC-MS results that the fractions of C7-C10 compounds in the bio-oil significantly increase. Inductively coupled plasma-atomic emission spectrometry, X-ray diffraction, and X-ray photoelectron spectroscopy analyses of the migration and transformation of Cu in the fast pyrolysis process show that more than 91% of the total Cu in the Cu-FSD is enriched in the char in the form of zerovalent Cu with a face-centered cubic crystalline phase. This study gives insight into catalytic fast pyrolysis of heavy metals, and demonstrates the technical feasibility of an eco-friendly process for disposal of heavy-metal-polluted biomass.


Assuntos
Biocombustíveis/normas , Biomassa , Cobre/isolamento & purificação , Recuperação e Remediação Ambiental/métodos , Temperatura Alta , Óleos/normas , Poluentes Químicos da Água/isolamento & purificação , Abies/química , Biodegradação Ambiental , Catálise , Carvão Vegetal/química , Espectroscopia de Ressonância Magnética , Espectroscopia Fotoeletrônica , Espectrofotometria Ultravioleta , Difração de Raios X
13.
ScientificWorldJournal ; 2012: 475027, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22593688

Resumo

In this study, the methanolysis process of sunflower oil was investigated to get high methyl esters (biodiesel) content using sodium methoxide. To reach to the best process conditions, central composite design (CCD) through response surface methodology (RSM) was employed. The optimal conditions predicted were the reaction time of 60 min, an excess stoichiometric amount of alcohol to oil ratio of 25%w/w and the catalyst content of 0.5%w/w, which lead to the highest methyl ester content (100%w/w). The methyl ester content of the mixture from gas chromatography analysis (GC) was compared to that of optimum point. Results, confirmed that there was no significant difference between the fatty acid methyl ester content of sunflower oil produced under the optimized condition and the experimental value (P ≥ 0.05). Furthermore, some fuel specifications of the resultant biodiesel were tested according to American standards for testing of materials (ASTM) methods. The outcome showed that the methyl ester mixture produced from the optimized condition met nearly most of the important biodiesel specifications recommended in ASTM D 6751 requirements. Thus, the sunflower oil methyl esters resulted from this study could be a suitable alternative for petrol diesels.


Assuntos
Biocombustíveis/análise , Biotecnologia/métodos , Metanol/metabolismo , Óleos de Plantas/metabolismo , Algoritmos , Biocombustíveis/normas , Catálise , Cromatografia Gasosa , Esterificação , Ésteres/metabolismo , Etanol/metabolismo , Ácidos Graxos/análise , Glicerol/metabolismo , Cinética , Óleo de Girassol , Triglicerídeos/metabolismo
14.
Waste Manag Res ; 30(4): 335-53, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22446971

Resumo

The utilization of solid recovered fuels (SRF) for energy recovery has been increasing steadily in recent years, and this development is set to continue. In order to use SRF efficiently, it is necessary to define quality standards and introduce targeted quality assurance measures. SRF can be used both in mono-incineration and in co-incineration systems, for instance in power generation and cement plants; but as quality requirements differ, it is necessary to unambiguously define the term 'solid recovered fuel'. The purpose of this article is to provide an overview of the origin, development and the current status of quality assurance for SRF. The basic principles of quality assurance for SRF are explained with reference to the development of the German RAL Quality Assurance System and in addition specifications that have emerged from European standardization work of CEN/TC 343 are analysed.


Assuntos
Biocombustíveis/normas , Eliminação de Resíduos/normas , Biocombustíveis/classificação , União Europeia , Alemanha , Incineração , Controle de Qualidade , Eliminação de Resíduos/legislação & jurisprudência
15.
Environ Sci Technol ; 45(12): 5447-53, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21591673

Resumo

In addition to available country or site-specific life cycle studies on Jatropha biodiesel we present a generic, location-independent life cycle assessment and provide a general but in-depth analysis of the environmental performance of Jatropha biodiesel for transportation. Additionally, we assess the influence of changes in byproduct use and production chain. In our assessments, we went beyond the impact on energy requirement and global warming by including impacts on ozone layer and terrestrial acidification and eutrophication. The basic Jatropha biodiesel system consumes eight times less nonrenewable energy than conventional diesel and reduces greenhouse gas emissions by 51%. This result coincides with the lower limit of the range of reduction percentages available in literature for this system and for other liquid biofuels. The impact on the ozone layer is also lower than that provoked by fossil diesel, although eutrophication and acidification increase eight times. This study investigates the general impact trends of the Jatropha system, although not considering land-use change. The results are useful as a benchmark against which other biodiesel systems can be evaluated, to calculate repayment times for land-use change induced carbon loss or as guideline with default values for assessing the environmental performance of specific variants of the system.


Assuntos
Biocombustíveis/análise , Biocombustíveis/normas , Conservação de Recursos Energéticos/métodos , Meio Ambiente , Jatropha/química , Ácidos/análise , Eutrofização , Aquecimento Global , Ozônio/análise , Padrões de Referência , Termodinâmica
16.
Environ Sci Technol ; 45(13): 5869-77, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21671646

Resumo

This consequential life cycle assessment study highlights the key environmental aspects of producing biogas from separated pig and cow slurry, a relatively new but probable scenario for future biogas production, as it avoids the reliance on constrained carbon cosubstrates. Three scenarios involving different slurry separation technologies have been assessed and compared to a business-as-usual reference slurry management scenario. The results show that the environmental benefits of such biogas production are highly dependent upon the efficiency of the separation technology used to concentrate the volatile solids in the solid fraction. The biogas scenario involving the most efficient separation technology resulted in a dry matter separation efficiency of 87% and allowed a net reduction of the global warming potential of 40%, compared to the reference slurry management. This figure comprises the whole slurry life cycle, including the flows bypassing the biogas plant. This study includes soil carbon balances and a method for quantifying the changes in yield resulting from increased nitrogen availability as well as for quantifying mineral fertilizers displacement. Soil carbon balances showed that between 13 and 50% less carbon ends up in the soil pool with the different biogas alternatives, as opposed to the reference slurry management.


Assuntos
Biocombustíveis/normas , Meio Ambiente , Aquecimento Global/prevenção & controle , Química Verde/métodos , Química Verde/tendências , Esterco , Animais , Carbono/análise , Bovinos , Sensibilidade e Especificidade , Solo/análise , Sus scrofa
17.
Biol Futur ; 72(3): 341-346, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34554554

Resumo

Biogas is the product of anaerobic digestion (AD) of organic waste and is considered to be one of the most valuable natural renewable energy carriers. Plant biomass represents the most abundant eco-friendly energy reservoir on Earth. However, the tenacious and heterogeneous structure of the lignocellulose-rich elements makes it difficult for the involved microbes to digest the recalcitrant substrates. Both the degradation process and the biogas production yield can be enhanced by appropriate pre-treatment of lignocellulosic materials. Filamentous fungi have been known as proficient colonizers of lignocellulosic plant tissues and have been recognized as producers of exceptionally rich and diverse hydrolytic enzymes. We tested Aspergillus nidulans, Trichoderma reesei, Rhizomucor miehei and Gilbertella persicaria filamentous fungal strains for pre-treatment of various agricultural lignocellulosic wastes. During the pre-treatment phase, the ß-glucosidase and endoglucanase activity was measured spectrophotometrically. In the AD step, methane production was monitored by gas chromatography. The preliminary results showed that all the applied strains (Aspergillus nidulans, Trichoderma reesei, Rhizomucor miehei and Gilbertella persicaria) were highly effective in producing both ß-glucosidase and endo-(1,4)-ß-D-glucanase enzymes, which might explain the greatly improved AD results. Pre-treatment with the above-mentioned filamentous fungi positively affected the biogas production, although the effect strongly depended on the selection of the fungal partner for any given biomass substrate. Depending on the used substrate and the pre-treatment strain, overall methane yields were elevated two-fold relative to the controls.


Assuntos
Agroquímicos/metabolismo , Biocombustíveis/microbiologia , Fungos/metabolismo , Resíduos Industriais/análise , Agroquímicos/síntese química , Biocombustíveis/normas , Fungos/química
18.
Biol Futur ; 72(4): 409-420, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34554493

Resumo

In the present scenario, alternative energy sources are required to achieve the future economic prosperity where shortage of fossil fuels will be a limiting factor and hamper the global economic growth. Therefore, interest in biofuel is increasing continuously. The best way of sustainable development is fossil fuel supplementation with biodiesel to reduce the fossil fuel demand. Biodiesel is a clean burning, ester-based, oxygenated fuel derived from natural and renewable sources. Till now, majority of the people have worked on the biodiesel derived from edible oil. Instead of using edible oil, non-edible oil needs to be explored as feedstock for biofuel because half of the world's population is unable to afford the food oil as feedstock for fuel production. Looking at the significance of biodiesel and the resources of biofuel, in this paper, a comparative exhaustive study has been reported with for three important plants, namely Jatropha curcas, Pongemia pinnata and Balanites aegyptiaca. These plants were selected based on their biodiesel potential, availability, cultivation practices and general information available. The present study involves scientometric publications, comparison of fatty acid composition and biodiesel parameters. We have also compared climatic conditions for the growth of the plants, economic feasibility of biodiesel production and other ecological services. The study paves a way for sustainable solution to policy makers and foresters looking for selection of plant species as bioenergy resource.


Assuntos
Biocombustíveis/normas , Extratos Vegetais/análise , Óleos de Plantas/análise , Balanites/química , Balanites/crescimento & desenvolvimento , Biocombustíveis/provisão & distribuição , Jatropha/química , Jatropha/crescimento & desenvolvimento , Millettia/química , Millettia/crescimento & desenvolvimento , Extratos Vegetais/biossíntese
19.
Conserv Biol ; 24(2): 412-23, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20028415

Resumo

The sustainable production of bioenergy is vital to avoiding negative impacts on environmental goods such as climate, soil, water, and especially biodiversity. We propose three key issues that should be addressed in any biodiversity risk-mitigation strategy: conservation of areas of significant biodiversity value; mitigation of negative effects related to indirect land-use change; and promotion of agricultural practices with few negative impacts on biodiversity. Focusing on biodiversity concerns, we compared principles and criteria set to address biodiversity and other environmental and social issues in seven standards (defined here as commodity-based standards or roundtables, or relevant European legislation): five voluntary initiatives related to bioenergy feedstocks, the Renewable Transport Fuel Obligation (United Kingdom), and the European Renewable Energy Source Directive. Conservation of areas of significant biodiversity value was fairly well covered by these standards. Nevertheless, mitigation of negative impacts related to indirect land-use change was underrepresented. Although the EU directive, with its bonus system for the use of degraded land and a subquota system for noncrop biofuels, offered the most robust standards to mitigate potential negative effects, all of the standards fell short in promoting agricultural practices with low negative impacts on biodiversity. We strongly recommend that each standard be benchmarked against related standards, as we have done here, and that efforts should be made to strengthen the elements that are weak or missing. This would be a significant step toward achieving a bioenergy industry that safeguards Earth's living heritage.


Assuntos
Agricultura/legislação & jurisprudência , Agricultura/normas , Biodiversidade , Biocombustíveis/normas , Conservação dos Recursos Naturais/legislação & jurisprudência , Ecossistema , União Europeia
20.
Biofouling ; 26(6): 623-35, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20628927

Resumo

Experiments were designed to evaluate the nature and extent of microbial contamination and the potential for microbiologically influenced corrosion of alloys exposed in a conventional high sulfur diesel (L100) and alternative fuels, including 100% biodiesel (B100), ultra-low sulfur diesel (ULSD) and blends of ULSD and B100 (B5 and B20). In experiments with additions of distilled water, all fuels supported biofilm formation. Changes in the water pH did not correlate with observations related to corrosion. In all exposures, aluminum 5052 was susceptible to pitting while stainless steel 304L exhibited passive behavior. Carbon steel exhibited uniform corrosion in ULSD and L100, and passive behavior in B5, B20, and B100.


Assuntos
Biocombustíveis/microbiologia , Biocombustíveis/normas , Corrosão , Eletroquímica
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