Improved Estimation of Bio-Oil Yield Based on Pyrolysis Conditions and Biomass Compositions Using GA- and PSO-ANFIS Models.

This paper incorporates the adaptive neurofuzzy inference system (ANFIS) technique to model the yield of bio-oil. The estimation of this parameter was performed according to pyrolysis conditions and biomass compositions of feedstock. For this purpose, this paper innovates two optimization methods including a genetic algorithm (GA) and particle swarm optimization (PSO). Primary data were gathered from previous studies and included 244 data of biodiesel oils. The findings showed a coefficient determination (R 2) of 0.937 and RMSE of 2.1053 for the GA-ANFIS model, and a coefficient determination (R 2) of 0.968 and RMSE of 1.4443 for PSO-ANFIS. This study indicates the capability of the PSO-ANFIS algorithm in the estimation of the bio-oil yield. According to the performed analysis, this model shows a higher ability than the previously presented models in predicting the target values and can be a suitable alternative to time-consuming and difficult experimental tests.

Application of Genetic Algorithm for Increasing the Utilization of Poor-quality Biodiesel through Blending.

Biodiesel is a viable alternative to petroleum diesel. The properties of the biodiesel depend on the feedstock used to produce it. A significant difference in properties exists between different biodiesels. Therefore, standards for biodiesel fuel had been developed considering many factors such as safe handling, corrosion, ignition quality, stability, cold flow property, and performance. For using biodiesel as fuel, the properties of the biodiesel should be within the limits specified in the standard. Unfortunately, biodiesel produced from many feedstocks does not comply with the specifications for all the properties. To utilize biodiesel with poor quality, biodiesels can be blended so that the properties of the blend comply with the specifications. Determining the optimal biodiesel blend ratio experimentally requires a lot of effort particularly when the number of parameters to be optimized is more and when the number of constituent biodiesels in the blend is more. In this work, the application of non-dominated sorting genetic algorithm to predict optimal blends for different scenarios is demonstrated.

Biofuels and Sustainability.

Energy security and climate change have cascading effects on the world's burgeoning population in terms of food security, environment, and sustainability. Due to depletion of fossil fuels and undesirable changes of climatic conditions, increase in air and water pollution, mankind started exploring alternate and sustainable means of meeting growing energy needs. One of the options is to use renewable sources of fuel-biofuel. In this chapter the authors have reviewed and presented sustainability impact on production of biofuels. Authors further reviewed state-of-the-art gene editing technologies toward improvement of biofuel crops. The authors recommend a phased transition from first-generation biofuel, and an acceleration toward use of technology to drive adoption of second-generation biofuels. Key aspects of technology and application of resource management models will enable these crops to bridge the global energy demand before we can completely transition to a more sustainable biofuel economy.

Household cooking fuel use and its health effects among rural women in southern India-A cross-sectional study.

The use of biomass fuel is associated with the deterioration of human health and women are more likely to develop health conditions due to their exposure to indoor air pollution during cooking. This study was conducted to assess the pattern of fuel used for cooking in households as well as to determine the association between the types of fuel used with respect to socio-demographic characteristics and health status of women. A community based cross-sectional survey was conducted between August 2016 and September 2018 in four rural areas and one semi-urban area of Udupi district, Karnataka, India. The study comprised 587 families including 632 women. A pre-tested semi-structured questionnaire was used to collect data on the type of fuel as well as self-reported health conditions. Overall, 72.5% of the families used biomass, where 67.2% families were currently using both biomass and liquefied petroleum gas while only biomass was used in 5.3% of the families for cooking. Among women, being ever exposed to biomass fuel was significantly associated with their age, literacy level, occupation and socio-economic status (p < 0.001). Those who were exposed to biomass fuel showed a significant association with self-reported ophthalmic (AOR = 3.85; 95% CI: 1.79-8.29), respiratory (OR = 5.04; 95% CI: 2.52-10.07), cardiovascular (OR = 6.07; 95% CI: 1.88-19.67), dermatological symptoms /conditions (AOR = 3.67; 95% CI: 1.07-12.55) and history of adverse obstetric outcomes (AOR = 2.45; 95% CI: 1.08-5.57). A positive trend was observed between cumulative exposure to biomass in hour-years and various self-reported health symptoms/conditions (p < 0.001). It was observed that more than two-thirds of women using biomass fuel for cooking were positively associated with self-reported health symptoms. Further longitudinal studies are essential to determine the level of harmful air pollutants in household environment and its association with various health conditions among women in this region.

Household biogas digesters or medium-large-scale biogas plants: a conflicting issue in rural China.

There has been a conflicting issue in rural China that whether or not encouraging the development of medium-large-scale biogas plants (MLBPs) to reduce household biogas digesters (HBDs) will be better for China in the long run. In this study, we investigate the difference between HBD users and MLBP users and the factors that affect the biogas use of these two user types on the basis of a survey of 1125 households in four provinces in China. The results indicate that compared to HBD users, MLBP users have a higher ratio (29%) of biogas use, obtain a higher subsidy-to-cost ratio (25%), and present a more positive evaluation of biogas service (3%). For HBD users, installation years and service evaluation are significant predictors of biogas use. For MLBP users, in addition to installation years and service, the subsidy-to-cost ratio affects biogas use negatively, and the biogas price is a key constraint for biogas use. These results provide valuable insights into the future development of biogas energy in rural China and guidance for the development of biogas in similar countries worldwide.

Table of contents Ujjwala 2. 0 from access to sustained usage

By September 2019, some 80 million poor households will have been connected to LPG since 2015 through the national programme, Pradhan Mantri Ujjwala Yojana (Ujjwala). This is in addition to "normal" growth in LPG connections amounting to approximately 40 million households. By any account, this is a remarkable achievement, bringing total households with LPG connections from about 60% of the country early this decade to some 95% by the beginning of the next. Connection, however, does not mean full usage and many new Ujjwala households and others continue to use significant amounts of biomass fuel, with consequent impacts on the health of village populations from the smoke. In addition, it is now well established that smoke from household biomass use is the largest single source of outdoor air pollution in the country, although of course not the only one.3 Its continued use thus is a problem for all Indians. How to continue to fulfill the promise of Ujjwala in its second phase, here called Ujjwala 2.0, is an important policy discussion in the country.

Assessing the efficiency of changes in land use for mitigating climate change.

Land-use changes are critical for climate policy because native vegetation and soils store abundant carbon and their losses from agricultural expansion, together with emissions from agricultural production, contribute about 20 to 25 per cent of greenhouse gas emissions1,2. Most climate strategies require maintaining or increasing land-based carbon3 while meeting food demands, which are expected to grow by more than 50 per cent by 20501,2,4. A finite global land area implies that fulfilling these strategies requires increasing global land-use efficiency of both storing carbon and producing food. Yet measuring the efficiency of land-use changes from the perspective of greenhouse gas emissions is challenging, particularly when land outputs change, for example, from one food to another or from food to carbon storage in forests. Intuitively, if a hectare of land produces maize well and forest poorly, maize should be the more efficient use of land, and vice versa. However, quantifying this difference and the yields at which the balance changes requires a common metric that factors in different outputs, emissions from different agricultural inputs (such as fertilizer) and the different productive potentials of land due to physical factors such as rainfall or soils. Here we propose a carbon benefits index that measures how changes in the output types, output quantities and production processes of a hectare of land contribute to the global capacity to store carbon and to reduce total greenhouse gas emissions. This index does not evaluate biodiversity or other ecosystem values, which must be analysed separately. We apply the index to a range of land-use and consumption choices relevant to climate policy, such as reforesting pastures, biofuel production and diet changes. We find that these choices can have much greater implications for the climate than previously understood because standard methods for evaluating the effects of land use4-11 on greenhouse gas emissions systematically underestimate the opportunity of land to store carbon if it is not used for agriculture.

Odour impact from farms with animal husbandry and biogas facilities.

Agricultural biogas facilities are usually combined with animal husbandry. Their siting near residential areas can lead to odour complaints by residents. The aim of this study was to identify relevant odour sources, to record odour impact, and to determine the main variables influencing odour impact. Therefore, a combined approach was designed to account for individual odour sources as well as the farms as a whole. On eight farms with cattle husbandry and biogas facilities, two of which kept pigs and poultry, the odour-relevant area sources ranged between 475 and 1810 m2. Solid manure from poultry, cattle and horses as well as grass cuttings, vegetable peelings, liquid-silage effluent and fermentation residues figured among the odour-intensive sources, in addition to biogas. Odour-plume inspections were performed at various distances from the farm, and assessors determined their odour perception and -intensities. The odour intensity in the downwind plume axis was explainable in a linear mixed-effects model by distance (p < 0.001), emitting surface area (p = 0.002) and wind speed (p = 0.018). As distance increased, odour intensity decreased by a factor of two per 50 m. Higher odour intensities resulted from larger surface areas in the animal enclosure, substrate storage, or especially odour-relevant sources. A mixture of odours was frequently perceived in the odour plume. If biogas escaped, an increase in odour impact was recognisable (p = 0.021). Biogas leakage should be avoided with a sufficiently large storage capacity, process optimisation, and regular servicing. In summary, animal husbandry and biogas facilities are to be viewed as an entire plant in terms of downwind odour perception. In planning processes for biogas facilities with animal husbandry, great care in the choice of site is called for, as are structural-technical and organisational measures for abatement.

Environmental impact of biogas: A short review of current knowledge.

The social acceptance of biogas is often hampered by environmental and health concerns. In this study, the current knowledge about the impact of biogas technology is presented and discussed. The survey reports the emission rate estimates of the main greenhouse gases (GHG), namely CO2, CH4 and N2O, according to several case studies conducted over the world. Direct emissions of gaseous pollutants are then discussed, with a focus on nitrogen oxides (NOx); evidences of the importance of suitable biomass and digestate storages are also reported. The current knowledge on the environmental impact induced by final use of digestate is critically discussed, considering both soil fertility and nitrogen release into atmosphere and groundwater; several case studies are reported, showing the importance of NH3 emissions with regards to secondary aerosol formation. The biogas upgrading to biomethane is also included in the study: with this regard, the methane slip in the off-gas can significantly reduce the environmental benefits.

Impact of military on biofuels consumption and GHG emissions: the evidence from G7 countries.

It was aimed to test the relation among the greenhouse gases emissions, economic growth, biofuels consumption, and militarization in G7 countries during the 1985-2015 period by Pedroni 1995 and panel Johansen tests and two long-run estimators-dynamic OLS and fully modified OLS. Long-run estimators found that economic growth and militarization have statistically significant positive impact on CO2 emission of G7 countries. Furthermore, the panel causality tests were applied: Dumitrescu and Hurlin (Econ Model 29(4):1450-1460, 2012) and panel Granger causality. These tests determined the causal relationship between the variables. The results of this paper implied that economic growth and biofuels consumption depend on militarization, and economic growth and militarization are granger causes of the greenhouse gases emissions.

Total environmental impacts of biofuels from corn stover using a hybrid life cycle assessment model combining process life cycle assessment and economic input-output life cycle assessment.

Studies on the environmental analysis of biofuels by fast pyrolysis and hydroprocessing (BFPH) have so far focused only on the environmental impacts from direct emissions and have included few indirect emissions. The influence of ignoring some indirect emissions on the environmental performance of BFPH has not been well investigated and hence is not really understood. In addition, in order to avoid shifting environmental problems from one medium to another, a comprehensive assessment of environmental impacts caused by the processes must quantify the environmental emissions to all media (air, water, and land) in relation to each life cycle stage. A well-to-wheels assessment of the total environmental impacts resulting from direct emissions and indirect emissions of a BFPH system with corn stover is conducted using a hybrid life cycle assessment (LCA) model combining the economic input-output LCA and the process LCA. The Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI) has been used to estimate the environmental impacts in terms of acidification, eutrophication, global climate change, ozone depletion, human health criteria, photochemical smog formation, ecotoxicity, human health cancer, and human health noncancer caused by 1 MJ biofuel production. Taking account of all the indirect greenhouse gas (GHG) emissions, the net GHG emissions (81.8 g CO2 eq/MJ) of the biofuels are still less than those of petroleum-based fuels (94 g CO2 eq/MJ). Maize production and pyrolysis and hydroprocessing make major contributions to all impact categories except the human health criteria. All impact categories resulting from indirect emissions except eutrophication and smog air make more than 24% contribution to the total environmental impacts. Therefore, the indirect emissions are important and cannot be ignored. Sensitivity analysis has shown that corn stover yield and bio-oil yield affect the total environmental impacts of the biofuels more significantly than the biomass transportation distance and biofuel transportation distance. Integr Environ Assess Manag 2018;14:139-149. © 2017 SETAC.

Drying or anaerobic digestion of fish sludge: Nitrogen fertilisation effects and logistics.

Application of fish sludge as fertiliser to agricultural land can contribute to closing nutrient cycles in fish farming. The effect of different treatment technologies on the nitrogen fertilisation effects of fish sludge was studied by a bioassay with barley (Hordeum vulgare), an incubation and a field experiment. Dried fish sludge resulted in relative agronomic efficiency of 50-80% compared with mineral fertiliser. The anaerobic digestate based on fish sludge (20 vol%) and dairy manure did not increase nitrogen uptake in barley. Increasing the ratio of fish sludge in the digestate increased the fertilisation effect, but requires optimisation of the biogas process. A simple logistics analysis conducted for a case hatchery showed that on-site drying and co-digestion of fish sludge in a central biogas plant can be regarded as equal in terms of costs. Norway can become an exporter of fish sludge-based recycling fertilisers if current regulations are modified to facilitate nutrient recycling.

The effects of biodiesels on semivolatile and nonvolatile particulate matter emissions from a light-duty diesel engine.

Semivolatile organic compounds (SVOCs) represent a dominant category of secondary organic aerosol precursors that are increasingly included in air quality models. In the present study, an experimental system was developed and applied to a light-duty diesel engine to determine the emission factors of particulate SVOCs (pSVOCs) and nonvolatile particulate matter (PM) components at dilution ratios representative of ambient conditions. The engine was tested under three steady-state operation modes, using ultra-low-sulfur diesel (ULSD), three types of pure biodiesels and their blends with ULSD. For ULSD, the contribution of pSVOCs to total particulate organic matter (POM) mass in the engine exhaust ranged between 21 and 85%. Evaporation of pSVOCs from the diesel particles during dilution led to decreases in the hydrogen to carbon ratio of POM and the PM number emission factor of the particles. Substituting biodiesels for ULSD could increase pSVOCs emissions but brought on large reductions in black carbon (BC) emissions. Among the biodiesels tested, tallow/used cooking oil (UCO) biodiesel showed advantages over soybean and canola biodiesels in terms of both pSVOCs and nonvolatile PM emissions. It is noteworthy that PM properties, such as particle size and BC mass fraction, differed substantially between emissions from conventional diesel and biodiesels.

Pulmonary Tuberculosis Is Associated With Biomass Fuel Use Among Rural Women in Pakistan: An Age- and Residence-Matched Case-Control Study.

Facility-based, age- and residential area-matched case-control study was conducted in Sindh, Pakistan to determine association between biomass fuel use for cooking and pulmonary tuberculosis (TB). Cases were women with pulmonary TB, and controls were those suffering from other diseases. Current users of biomass fuel were at higher risk of pulmonary TB (adjusted matched odds ratio [mOR] = 3.0; 95% CI = 1.1-4.9) compared with nonusers. In comparison with former biomass users (women not using biomass for >10 years), recent biomass users (women who switched from biomass to nonbiomass ≤10 years ago), and current (lifetime) users were at a higher risk in a dose-response manner (adjusted mOR = 2.8, 95% CI = 0.9-8.2 and adjusted mOR = 3.9, 95% CI = 1.4-10.7, respectively). Population attributable fraction for TB related to biomass fuel use was 40.6% (95% CI = 35.5%-45.7%). This study strengthens the evidence that biomass fuel use for cooking is associated with pulmonary TB and risk increases with duration of exposure.

The impact of biogas and fuelwood use on institutional kitchen air quality in Kampala, Uganda.

Experts have suggested that microscale biogas systems offer a source of renewable energy that improves indoor air quality, but such impacts have not been directly measured. This study documented cooking behaviors and measured 2.5-µm particulate matter (PM2.5 ), carbon monoxide (CO), and sulfur dioxide (SO2 ) concentrations within 14 institutional kitchens in Kampala, Uganda, that prepare meals using biogas (n=5), a mixture of biogas and fuelwood (n=3), and fuelwood (n=6). Small institutions (10-30 people) with biogas kitchens had 99% lower concentrations of PM2.5 (21 µg/m3 ) than fuelwood kitchens (3100 µg/m3 ). Larger institutions (>100 people) had biogas systems that produced insufficient gas and relied on fuelwood to meet over 90% of their energy needs. PM2.5 concentrations in these biogas-firewood kitchens were equivalent to concentrations in fuelwood kitchens. Although concentrations of hydrogen sulfide (H2 S) in biogas were as high as 2000 ppm, 75% of systems had undetectable H2 S levels (<100 ppm) in the biogas. Kitchens using biogas with high H2 S had correspondingly higher SO2 concentrations in the kitchen air. However, even the highest SO2 concentration in biogas kitchens (150 µg/m3 ) was lower than SO2 concentration in fuelwood kitchens (390 µg/m3 ). The results suggest that biogas systems can offer air quality improvements if sized properly for energy demands.

Glicerina bruta em dietas de juvenis de tambaqui / Crude glycerin in diets of juvenile tambaqui

Este estudo verificou o nível de glicerina bruta em substituição total do óleo de soja e parcial do milho em dietas de juvenis de tambaqui sem que o ingrediente interfira no desempenho zootécnico desses animais. O trabalho foi realizado na Universidade Federal do Tocantins, avaliando cinco níveis de inclusão da glicerina bruta (0%; 7,5%; 10%; 12,5% e 15%) em três repetições com 10 animais cada (n=150 tambaquis). Esses animais foram alimentados com as rações experimentais por um período de 75 dias (15 dias de adaptação e 60 dias experimentais). Ao final desse período, os animais foram contidos para a mensuração dos valores do desempenho zootécnico dos animais (taxa de crescimento específico, conversão alimentar aparente, eficiência alimentar, índice hepatossomático, ganho de peso e fator de condição). Durante o período experimental, não houve mortalidade, e de todos os índices avaliados apenas no fator de condição do animal ocorreu diferença estatística, quando se comparou o período inicial e o final do experimento. A inclusão de até 15% de glicerina bruta em dietas de tambaqui em substituição total do óleo de soja e parcial do milho pode ser realizada sem que prejudique o desempenho zootécnico da espécie estudada.(AU)

This study examined the level of crude glycerin in total replacement of soybean oil and partial replacement of corn in diets for tambaqui without ingredient interfering on the growth performance of these animals. The study was conducted at the Federal University of Tocantins, evaluating five levels of crude glycerin inclusion (0%, 7.5%, 10%, 12.5%, and 15%) in 3 replicates with 10 animals each (n = 150 tambaqui.) These animals were fed the experimental diets for a period of 75 days (15 days of adaptation and 60 days of trial), at the end of this period the animals were restrained to measure the values of the growth performance of animals (Specific growth rate, apparent food conversion, feed efficiency, hepatosomatic index, weight gain, and condition factor). During the study period, there were no deaths and in all indices evaluated, only the animal's condition factor presented statistical difference when comparing the initial and final periods of the experiment. The inclusion of up to 15% crude glycerin in tambaqui diets in total replacement of soybean oil and partial replacement of corn can be used without prejudice to the growth performance of the species studied.(AU)

Environmental balance of the UK biogas sector: An evaluation by consequential life cycle assessment.

Anaerobic digestion (AD) is expanding rapidly in the UK. Previous life cycle assessment (LCA) studies have highlighted the sensitivity of environmental outcomes to feedstock type, fugitive emissions, biomethane use, energy conversion efficiency and digestate management. We combined statistics on current and planned AD deployment with operational data from a survey of biogas plant operators to evaluate the environmental balance of the UK biogas sector for the years 2014 and 2017. Consequential LCA was applied to account for all major environmental credits and burdens incurred, including: (i) substitution of composting, incineration, sewer disposal, field decomposition and animal feeding of wastes; (ii) indirect land use change (ILUC) incurred by the cultivation of crops used for biogas production and to compensate for bakery and brewery wastes diverted from animal feed. In 2014, the UK biogas sector reduced greenhouse gas (GHG) emissions by 551-755Gg CO2e excluding ILUC, or 238-755Gg CO2e including ILUC uncertainty. Fossil energy depletion was reduced by 8.9-10.8PJe, but eutrophication and acidification burdens were increased by 1.8-3.4Gg PO4e and 8.1-14.6Gg SO2e, respectively. Food waste and manure feedstocks dominate GHG abatement, largely through substitution of in-vessel composting and manure storage, whilst food waste and crop feedstocks dominate fossil energy credit, primarily through substitution of natural gas power generation. Biogas expansion is projected to increase environmental credits and loadings by a factor of 2.4 by 2017. If all AD bioelectricity replaced coal generation, or if 90% of biomethane replaced transport diesel or grid natural gas, GHG abatement would increase by 131%, 38% and 20%, respectively. Policies to encourage digestion of food waste and manures could maximize GHG abatement, avoiding the risk of carbon leakage associated with use of crops and wastes otherwise used to feed livestock. Covering digestate stores could largely mitigate net eutrophication and acidification burdens.

Clean fuels for resource-poor settings: A systematic review of barriers and enablers to adoption and sustained use.

BACKGROUND: Access to, and sustained adoption of, clean household fuels at scale remains an aspirational goal to achieve sufficient reductions in household air pollution (HAP) in order to impact on the substantial global health burden caused by reliance on solid fuels. AIM AND OBJECTIVES: To systematically appraise the current evidence base to identify: (i) which factors enable or limit adoption and sustained use of clean fuels (namely liquefied petroleum gas (LPG), biogas, solar cooking and alcohol fuels) in low- and middle-income countries; (ii) lessons learnt concerning equitable scaling-up of programmes of cleaner cooking fuels in relation to poverty, urban-rural settings and gender. METHODS: A mixed-methods systematic review was conducted using established review methodology and extensive searches of published and grey literature sources. Data extraction and quality appraisal of quantitative, qualitative and case studies meeting inclusion criteria were conducted using standardised methods with reliability checking. FINDINGS: Forty-four studies from Africa, Asia and Latin America met the inclusion criteria (17 on biogas, 12 on LPG, 9 on solar, 6 on alcohol fuels). A broad range of inter-related enabling and limiting factors were identified for all four types of intervention, operating across seven pre-specified domains (i.e. fuel and technology characteristics, household and setting characteristics, knowledge and perceptions, financial, tax and subsidy aspects, market development, regulation, legislation and standards, and programme and policy mechanisms) and multiple levels (i.e. household, community, national). All domains matter and the majority of factors are common to all clean fuels interventions reviewed although some are fuel and technology-specific. All factors should therefore be taken into account and carefully assessed during planning and implementation of any small- and large-scale initiative aiming at promoting clean fuels for household cooking. CONCLUSIONS: Despite limitations in quantity and quality of the evidence this systematic review provides a useful starting point for the design, delivery and evaluation of programmes to ensure more effective adoption and use of LPG, biogas, alcohol fuels and solar cooking. FUNDING: This review was funded by the Department for International Development (DfID) of the United Kingdom. The authors would also like to thank the Evidence for Policy and Practice Information and Co-ordinating Centre (EPPI-Centre) for their technical support.