Experimental Characterization of a Small-Scale Downdraft Gasifier for Biomass Waste

Volume 5: Energy Systems Analysis, Thermodynamics and Sustainability; NanoEngineering for Energy; Engineering to Address Climate Change, Parts A and B ◽

10.1115/imece2010-37392 ◽

2010 ◽

Cited By ~ 2

Author(s):

Vaughn M. Emmerson ◽

Gerardo Diaz

Keyword(s):

Agricultural Waste ◽

Molar Fraction ◽

Global Scale ◽

Small Scale ◽

Fuel Wood ◽

Biomass Waste ◽

Yard Waste ◽

Downdraft Gasifier ◽

Many Sources

Biomass is essentially organic garbage obtained from many sources of dead or live vegetation including yard waste. According to recent data, approximately sixty million bone dry tons of biomass are produced in California each year [1]. Of this, only five million tons are used for the generation of electricity. At a global scale, 8700 Tg of biomass (dry matter) were burned without energy recovery in 1991. This number has increased especially in developing countries with the main sources being the savannas, agricultural waste, tropical forests, and fuel wood. Inefficient burning of waste, through combustion in open-air or in open dumps are a significant source of pollutants leading to possible health effects. An alternative to open air combustion is gasification, which involves the conversion of biomass to generate synthesis gas (syngas) by adding heat and limited amounts of oxygen. Several gasifying agents can be utilized, but air is commonly used in small-scale gasifiers. The use of air causes a large molar fraction of nitrogen in the syngas composition. This papers shows the experimental results obtained with a commercially available small-scale downdraft gasifier. Woodchips obtained from a nearby landfill are used as input to the gasifier and temperatures, flow rates, and syngas composition are reported and analyzed.

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Organic Waste in Composting: A brief review

International Journal of Current Engineering and Technology ◽

10.14741/ijcet.v8i01.10884 ◽

2018 ◽

Vol 8 (01) ◽

Cited By ~ 4

Author(s):

Suhas S. Gonawala ◽

Hemali Jardosh

Keyword(s):

Solid Waste ◽

Organic Waste ◽

Low Cost ◽

Agricultural Waste ◽

Negative Effects ◽

Yard Waste ◽

Composting Process ◽

Carbon Nitrogen Ratio ◽

Phosphorus And Potassium ◽

Many Sources

This work studied on the composting process of organic waste. Organic waste is the easily biodegradable waste. Organic wastes are produced from many sources Such as agricultural waste, market waste, kitchen waste, urban solid waste and municipal solid waste. Without proper management, this waste could create several environments problem. Therefore, composting is the best low-cost alternative solution to overcome this problem. The composting method can degrade all types of organic waste such as fruits, vegetables, plants, yard waste and others. The organic waste composition can be used as nutrients for crops, soil additives and for environmental management. However, many factors can contribute to the quality of compost products since different types of organic waste have different concentrations of nutrients, Nitrogen, Phosphorus and Potassium (N, P, K) that are the common macro energetics present in fertilizers. The presence of heavy metals shows how Composts can be applied to soils without contributing any negative effects. In terms of the factor affecting the composting process, temperature, pH, moisture content and carbon nitrogen ratio (C: N) are the main parameters that contribute to the efficiency of the composting process.

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Urban pollution control strategy: SBR technology to treat agricultural waste from pig farm in Indonesia

Sains & Teknologi ◽

10.24123/jst.v2i2.2250 ◽

2019 ◽

Vol 2 (2) ◽

pp. 21

Author(s):

Lindawati Lindawati

Keyword(s):

Cost Estimation ◽

Batch Reactor ◽

Agricultural Waste ◽

Cost Effective ◽

Land Application ◽

Pig Manure ◽

Small Scale ◽

Piggery Wastewater ◽

Pig Farm ◽

Number Of Customers

Reduction of food rations and shortages is one of the impacts of the increasing human population. Food sector industries then try to cope with the fast growing number of customers. Agribusiness sector gains its popularity in these recent years, including pig farm. The increase trend of animal farming industry is likely to bring increasing pollution problem unless effective treatment methods are used. The main problems related to the pig farm include odor nuisance and pig manure disposal. The existing land application of piggery wastewater is the traditional way to discharge the wastewater. This may yield in land and water contamination, due to the accumulation of unused nutrients by crop plant. A case study of a large commercial pig farm from Australia is proposed to apply in smaller scale in Indonesia. Operational strategies for the small-scale SBR (Sequencing Batch Reactor) treating piggery effluent were developed based on lab-scale experiments. Due to SBR characteristics, which are money-saving and space-saving, it is very suitable to be applied in urban area. An economic evaluation was made of various process options. The cost estimation showed that SBR is a cost effective process, allowing operational batches to be adjusted to reduce unnecessary aeration cost. A reduction in the aeration cost was achieved by shortening the batch time from 24-h to 8-h. A comparison of three different SBR options showed that smaller size reactors could be more flexible and cost effective when compared with the larger ones.

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Optical and Chemical Characterization of Aerosols Emitted from Coal, Heavy and Light Fuel Oil, and Small-Scale Wood Combustion

Environmental Science & Technology ◽

10.1021/es4028698 ◽

2013 ◽

Vol 48 (1) ◽

pp. 827-836 ◽

Cited By ~ 11

Author(s):

Anna K. Frey ◽

Karri Saarnio ◽

Heikki Lamberg ◽

Fanni Mylläri ◽

Panu Karjalainen ◽

...

Keyword(s):

Chemical Characterization ◽

Fuel Oil ◽

Small Scale ◽

Wood Combustion

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SPEAR (Solar Pyrolysis Energy Access Reactor): Theoretical Design and Evaluation of a Small-Scale Low-Cost Pyrolysis Unit for Implementation in Rural Communities

Energies ◽

10.3390/en14082189 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2189

Author(s):

Cesare Caputo ◽

Ondřej Mašek

Keyword(s):

Waste Management ◽

Rural Areas ◽

Net Present Value ◽

Agricultural Waste ◽

Tracking Error ◽

Sub Saharan Africa ◽

Small Scale ◽

Energy Access ◽

Efficient System ◽

Pyrolysis Unit

Energy access and waste management are two of the most pressing developmental and environmental issues on a global level to help mitigate the accelerating impacts of climate change. They are particularly relevant in Sub–Saharan Africa where electrification rates are significantly below global averages and rural areas are lacking a formal waste management sector. This paper explores the potential of integrating solar energy into a biomass pyrolysis unit as a potentially synergetic solution to both issues. The full design of a slow pyrolysis batch reactor targeted at biochar production, following a strict cost minimization approach, is presented in light of the relevant considerations. SPEAR is powered using a Cassegrain optics parabolic dish system, integrated into the reactor via a manual tracking system and optically optimized with a Monte-Carlo ray tracing methodology. The design approach employed has led to the development an overall cost efficient system, with the potential to achieve optical efficiencies up 72% under a 1.5° tracking error. The outputs of the system are biochar and electricity, to be used for soil amendment and energy access purposes, respectively. There is potential to pyrolyze a number of agricultural waste streams for the region, producing at least 5 kg of biochar per unit per day depending on the feedstock employed. Financial assessment of SPEAR yields a positive Net Present Value (NPV) in nearly all scenarios evaluated and a reasonable competitiveness with small scale solar for electrification objectives. Finally, SPEAR presents important positive social and environmental externalities and should be feasibly implementable in the region in the near term.

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Remote Sensing Methods for the Biophysical Characterization of Protected Areas Globally: Challenges and Opportunities

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi10060384 ◽

2021 ◽

Vol 10 (6) ◽

pp. 384

Author(s):

Javier Martínez-López ◽

Bastian Bertzky ◽

Simon Willcock ◽

Marine Robuchon ◽

María Almagro ◽

...

Keyword(s):

Remote Sensing ◽

Protected Areas ◽

Large Scale ◽

Anthropogenic Activities ◽

Global Scale ◽

Area Network ◽

Biophysical Characterization ◽

Challenges And Opportunities ◽

Scale Characterization

Protected areas (PAs) are a key strategy to reverse global biodiversity declines, but they are under increasing pressure from anthropogenic activities and concomitant effects. Thus, the heterogeneous landscapes within PAs, containing a number of different habitats and ecosystem types, are in various degrees of disturbance. Characterizing habitats and ecosystems within the global protected area network requires large-scale monitoring over long time scales. This study reviews methods for the biophysical characterization of terrestrial PAs at a global scale by means of remote sensing (RS) and provides further recommendations. To this end, we first discuss the importance of taking into account the structural and functional attributes, as well as integrating a broad spectrum of variables, to account for the different ecosystem and habitat types within PAs, considering examples at local and regional scales. We then discuss potential variables, challenges and limitations of existing global environmental stratifications, as well as the biophysical characterization of PAs, and finally offer some recommendations. Computational and interoperability issues are also discussed, as well as the potential of cloud-based platforms linked to earth observations to support large-scale characterization of PAs. Using RS to characterize PAs globally is a crucial approach to help ensure sustainable development, but it requires further work before such studies are able to inform large-scale conservation actions. This study proposes 14 recommendations in order to improve existing initiatives to biophysically characterize PAs at a global scale.

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