548 research outputs found
Urban wind power and the private sector : community benefits, social acceptance and public engagement
Get PDFGiven the ambitious government targets for renewable energy generation in the UK, there has been a push by government and industry towards various types and scales of Renewable Energy Technologies (RETs). This paper explores the implications of commercial urban wind projects for local communities, drawing on a case study of proposals by ASDA to construct wind turbines in two semi-urban locations in the UK. The paper argues that community responses to the proposals were complex and varied and could not adequately be encapsulated by 'nimby' (not in my back yard) assignations. It concludes that while ASDA followed a process of consulting local people, this process highlighted the problems of the 'business as usual' approach to public engagement employed by ASDA, and assumptions made about public acceptance of RETs
Support af nye natur/teknik-lĂŠrere
Get PDFArtiklen fremlĂŠgger et forslag til en model for fremtidige tiltag til stĂžtte af nyuddannede danske natur/teknik-lĂŠrere med henblik pĂ„ at Ăžge deres udviklingsparathed og sandsynligheden for deres fastholdelse i lĂŠrerprofessionen. Modellen kombinerer resultater fra danske forsknings- og udviklingsprojekter og introducerer tre nye begreber (support, innovativ lĂŠrer, self-effi cacy) i den danske naturfagsdidaktiske diskurs i forhold til nyuddannede natur/teknik-lĂŠreres fastholdelse og udvikling. Der pĂ„vises en sammenhĂŠng mellem support fra skolens undervisningsmiljĂž og natur/teknik-lĂŠreres tiltro til egen formĂ„en og gennemslagskraft i en specifik sammenhĂŠng. Det beskrives hvordan support i et dansk udviklingsprojekt har vist sig givtigt for bĂ„de nye lĂŠrere og CVU-undervisere. Ăget opmĂŠrksomhed pĂ„ support fra skolernes side og mĂ„ske ogsĂ„ en direkte support fra CVUâerne bliver her anfĂžrt som potentielt nyttigt for nyuddannede natur/teknik-lĂŠrere
Characterization of Biochars Produced From Peanut Hulls and Pine Wood with Different Pyrolysis Conditions
Get PDFBackground
Application of modern biomass pyrolysis methods for production of biofuels and biochar is potentially a significant approach to enable global carbon capture and sequestration. To realize this potential, it is essential to develop methods that produce biochar with the characteristics needed for effective soil amendment.
Methods
Biochar materials were produced from peanut hulls and pine wood with different pyrolysis conditions, then characterized by cation exchange (CEC) capacity assays, nitrogen adsorptionâdesorption isotherm measurements, micro/nanostructural imaging, infrared spectra and elemental analyses.
Results
Under a standard assay condition of pH 8.5, the CEC values of the peanut hull-derived biochar materials, ranging from 6.22 to 66.56 cmol kgâ1, are significantly higher than those of the southern yellow pine-derived biochar, which are near zero or negative. The biochar produced from peanut hulls with a steam activation process yielded the highest CEC value of 66.56 cmol kgâ1, which is about 5 times higher than the cation exchange capacity (12.51 cmol kgâ1) of a reference soil sample. Notably, biochar produced from peanut hulls with batch barrel retort pyrolysis also has a much higher CEC value (60.12 cmol kgâ1) than that (12.45 cmol kgâ1) from Epridaâs H2-producing continuous steam injection process. The CEC values were shown to correlate well with the ratios of oxygen atoms to carbon atoms (O:C ratios) in the biochar materials. The higher O:C ratio in a biochar material may indicate the presence of more hydroxyl, carboxylate, and carbonyl groups that contribute to a higher CEC value for the biochar product. In addition, the increase in surface area can also play a role in increasing the CEC value of biochar, as in the case of the steam activation char.
Conclusion
Comparison of characterization results indicated that CEC value is determined not only by the type of the source biomass materials but also by the pyrolysis conditions. Biochar with the desirable characteristics of extremely high surface area (700 m2/g) and cation exchange capacity (\u3e 60 cmol kg) was created through steam activation
- âŠ
