Fuel cells for power generation and organic waste treatment on the island of Mull

In-situ use of biomass and organic waste streams have the potential to provide the key to energy self sustainability for islands and remote communities. Traditionally biogas fuels have been used in combustion engines for electric power generation. However, fuel cells offer the prospect of achieving higher generating efficiencies, and additionally, important environmental benefits can be achieved by way of mitigating greenhouse gas emissions, whilst providing a carbon sink. This paper presents the design details of a biogas gas plant and fuel cell installation that will provide a practical solution on an island (and be applicable in other remote and rural areas) where connection to the grid can be expensive, and where biofuels can be produced on site at no significant extra cost

Aerated compost tea (ACT) to improve soil biology and to act as a biofertiliser/biofungicide (OK-Net Arable Practice abstract)

There is a growing body of evidence supporting the benefits of aerated compost tea (ACT) application, but not all studies have shown this conclusively. Compost tea application helps build healthy soils which can lead to benefits for the crop including improved crop health and nutrition, improved crop quality, as well as growth promotion and plant protection through pathogen suppression. Additionally ACT may also help crops cope better with abiotic stress factors such as drought. Practical recommendation • Exact methods of composting and compost tea making (aerobic vs anaerobic) are open to debate, but this practice abstract will focus on the method for producing aerobic compost tea. • The most important step is to produce mature, well aerated compost full of the beneficial microorganisms needed in the soil and by the plant. Compost should be regularly turned to maintain levels of Oxygen while avoiding the build-up of CO2 (to avoid anaerobic conditions) and keeping the temperature below 65 degrees C. • Production of quality compost is the most important step in making high quality, beneficial compost tea. • Compost feedstocks can be adapted to give the right balance (50:50 by weight fungal/bacterial ratio) of microorganisms. • The composition of any compost tea will be affected by the ingredients used to make it, e.g. woodchip has been shown necessary to increase the proportion of fungi in composts. Using only farm manure and green waste will tend to produce composts which are relatively low in fungi. • Cereal crops benefit from a fungal dominant brew which can be created using certain feedstocks in the compost and by brewing the compost tea for a longer period of time (48 hrs). • Oxygenate the compost in a brewer for 24 to 48 hrs. If using tap water, remove chlorine by aerating the water in the brewer for a few hours prior to adding compost. To stimulate microbial growth, molasses can be used or more complex additions can be bought that may contain among other things seaweed extract. • Prior to spraying the compost tea must be filtered to remove any compost as this will cause blockages in the sprayer. Spray pressure should not exceed 2.5 bar (1-2 bar is preferable) and nozzle size should not be too fine as this will damage the delicate fungi in the brew. Spray volume should be around 250-300 l per ha. • Soil drench post drilling application followed by 2 or 3 more applications, while the crop is still young (around 2-3 leaves), and at the highest disease pressure point (typically GS37 to 65 for cereals) is a good approach. On-farm demonstrations have involved a 3-spray-strategy in April, May and June after a March drilling of a spring cereal

Performance of summer sunflower (Helianthus annuus L.) hybrids under different nutrient management practices in coastal Odisha

The field experiment was conducted at Department of Agronomy, College of Agriculture, OUAT, Bhubaneswar during summer 2014 to find out appropriate hybrids and nutrient management practices for summer sunflower. Application of recommended dose of Fertiliser(RDF) i.e. 60-80- 60 kg N, P2O5-K2O ha -1 + ZnSO4 @ 25 kg ha -1 recorded the maximum capitulum diameter (15.60cm), seed yield (2.17 t ha -1 ), stover yield (4.88 t ha -1 ) and oil yield (0.91 t ha -1 ), while application of RDF + Boron@ 1 kg ha-1 recorded the highest number of total seed (970) and filled seed per capitulum (890) with the lowest unfilled seed (80) and sterility percentage (9.0%). The hybrid ‘Super-48’ recorded the highest seed and oil yield of 2.17 and 0.91 t ha -1 , respectively, at recommended dose of fertiliser + ZnSO4 @ 25 kg ha -1 . Experiment was conducted in evaluating the new hybrids in addition to evaluate the response of variety to different nutrient management practices

Nutrient Recovery by Biogas Digestate Processing

This report reviews various approaches for processing of biogas plant digestate for the purpose of nutrient recovery. It covers both established and emerging technologies and assesses technical performance and where possible economics. Techniques for nutrient recovery from digestate are developing rapidly and aiming to improve nutrient management in agriculture and in waste treatment systems. The report is aimed at biogas plant developers and operators as well as agriculture policy makers and was produced by IEA Bioenergy Task 37. IEA Bioenergy Task 37 addresses challenges related to the economic and environmental sustainability of biogas production and utilisation.JRC.F.8-Sustainable Transpor

Potential production of biogas from prinkly pear (opuntia ficus-indica L.) in sicilian uncultivated areas

The aim of this work is to evaluate the potential production of biogas and, indirectly, biomethane or electric and thermal energy, from prinkly pear (Opuntia ficus-indica L.), to be grown in a part of Sicilian uncultivated areas and co-digested together with the available livestock manure and slurry. In order to increase the Renewable Energy Sources (RES) and reduce the dependency from fossil ones, the conversion of biomass into biogas through Anaerobic Digestion (AD) process is paramount for producing biomethane, to be used as fuel for means of transport and agricultural machines or heating, or electric and thermal energy through Combined Heat and Power (CHP) plants. Moreover, the digestate produced through AD process can be applied to soils as organic fertiliser in the place of chemical ones. Prinkly pear was supposed to be grown, by mechanising the harvest of cladods (modified stems), in a part of the Sicilian Used Agricultural Area that is currently uncultivated (totally 600, 000 ha ca.), identified by means of a GIS software. Thus it was possible to compute the potential production of biogas and, indirectly, biomethane or electric and thermal energy. The results show that the Sicilian potential production of biogas is 612, 115 103m3, from which 342, 784 103m3of biomethane could be extracted or 67, 038 MWh of electric energy and 70, 390 MWh MWh of thermal energy could be generated. Moreover the obtained digestate would be used as biofertiliser, within both conventional and organic farming. This work demonstrates that the production of RES, such as biogas from prinkly pear, represents a very profitable way of using the uncultivated areas: the income of the farmer would include not only that deriving from the sale of biomethane or electric and thermal energy but also the saving for replacing chemical fertilisers with digestate and the subsidy for producing biomethane as fuel for means of transport or electric and thermal energy from biogas

Bio-Fertilizers via Co-Digestion: a Review

In diversifying the economies of most oil producing countries especially in regions with arable lands, Agriculture becomes the next choice aside mineral deposits. This has led to a search for an alternative to inorganic fertilizers, the alternatives are the biofertilizers. The paper discussed the classification of the anaerobic co-digestion process based on the application of inoculants to the biodigester feedstock to speed up the digestion process and the absence of inoculants. Biodigester feedstock also looked at the various mechanisms in the digestion process which includes hydrolysis, acidogenesis, acetogenesis, and methanogenesis, the pathways were illustrated with chemical equations and various microorganisms that take part in the anaerobic process were mentioned and tabulated. The types of biofertilizers, merits, and demerits, the difference between biofertilizers and organic fertilizers were comprehensively discussed. Current trends on the application of the co-digestion technique to improve the yield, nutrient, and safety of biofertilizers and also the recent progression on the technique were mentioned

The biogas value chains in the Swedish region of Skåne

Biogas systems are complex in the sense that they cut across several sectors, mainly agriculture, waste management and energy. Cooperation between actors in these sectors must work for biogas projects to be realised and successful. The aim of this report is to describe the biogas systems in Skåne from a value chain perspective, including important development pathways. The different segments in the value chain are mapped with regard to actors, actors in supporting activities, technologies and institutions (mainly regulations). Skåne is a fairly small part of Sweden in terms of land area but it is the most important agricultural and food producing region in Sweden and comparatively densely populated. These characteristics explain why Skåne is an important (if not the most important) biogas region in Sweden. The earliest applications of biogas were for the purpose of reducing the volume of sewage from waste water treatment plants. The biogas produced was used mainly for plant process needs and part of it was often flared. Much of the biogas today, from a variety of types of biogas plants, is upgraded and used for transport. The development towards transport applications can be traced back to the desire to reduce oil dependence and urban air pollution from diesel buses. Initially buses were converted to compressed natural gas, but with regional ambitions for fossil free public transport attention in recent years has turned to compressed biogas. Biogas value chains have developed in response to sustainability concerns in energy and transport, sewage sludge and waste handling, and in agriculture. The development has generated new business opportunities, especially in the field of upgrading. The production of biogas, for transport fuel, waste handling and fertiliser, is expected to continue to grow in Skåne