The Experts below are selected from a list of 23595 Experts worldwide ranked by ideXlab platform
Margareta Wihersaari - One of the best experts on this subject based on the ideXlab platform.
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from wood pellets to wood chips risks of degradation and Emissions from the storage of woody biomass a short review
Renewable & Sustainable Energy Reviews, 2016Co-Authors: Esa Alakoski, Miia Jamsen, David Agar, Elina Tampio, Margareta WihersaariAbstract:The compounds in stored woody biomass degrade as a result of chemical and/or biological processes during storage. These processes produce Gaseous Emissions. Recent studies concerning Gaseous Emissions from wood pellet storages are reviewed herein. The applicability of the results from pellet research to wood chips is discussed. Thorough scientific understanding on the storage phenomena of wood chips is extremely important as the threat of climate change and the need to reduce greenhouse gas Emissions have led to an increased need to large scale wood chip storage to ensure supply. Typically the gases produced from stored woody biomasses are carbon monoxide (CO), carbon dioxide (CO2), methane (CH4), and other volatile hydrocarbons e.g. aldehydes and terpenes. CO2 and CH4 are greenhouse gases with high global warming potential. Chemical degradation via auto-oxidation of fats and fatty-acids seems to be the dominant mechanism for off-gassing from stored wood pellets, whereas biological processes are mainly responsible for the Gaseous Emission from wood chips. In confined storage spaces Gaseous Emissions may lead to oxygen depletion. Oxygen depletion together with a high CO concentration poses a serious health risk for those working in such conditions. The degradation processes also result in dry matter losses and in spontaneous heating and in the worst case, especially in large piles, spontaneous ignition of the stored material. Thorough and systematic scientific studies on degradation processes and their effects are needed in order to understand and minimise risks from large scale wood chips storage to human health, environment and property.
Mohd Ali Hassan - One of the best experts on this subject based on the ideXlab platform.
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microwave assisted pre carbonisation of palm kernel shell produced charcoal with high heating value and low Gaseous Emission
Journal of Cleaner Production, 2017Co-Authors: Nahrul Hayawin Zainal, Astimar Abdul Aziz, Juferi Idris, Ropandi Mamat, Ezyana Kamal Bahrin, Mohd Ali Hassan, Suraini AbdazizAbstract:Abstract Production of charcoal with a high higher heating value (HHV) while maintaining low Gaseous Emission requires high energy input and complicated methods. This paper presents a study of the production of charcoal with high HHV and low Gaseous Emission from palm kernel shell (PKS) within a microwave-assisted pre-carbonisation system. The maximum temperature was 300 °C, and three magnetrons were employed to assist with the pre-carbonisation process. The magnetrons were programmed to automatically shut down when the temperature reached 250 °C. Carbonisation took place when the PKS was combusted and the resulting heat was used to sustain the carbonisation. The Gaseous Emission was passed through a condensation unit and a scrubber system connected to the microwave reactor. Untreated PKS biomass with particle size of 6–15 mm was used in this study. A high HHV of 27.63 MJ/kg was obtained. The concentrations for the particulate matter with a size of 10 μm and below (PM10), CO, NO2, SO2 and HCl were below the standard limits set by the Malaysian Ambient Air Quality Standards (2014). Therefore, the microwave-assisted pre-carbonisation technology proposed in this study produced charcoal with high HHV and low Gaseous Emission which can be used as co-combustion for renewable energy generation.
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Self-sustained carbonization of oil palm biomass produced an acceptable heating value charcoal with low Gaseous Emission
Journal of Cleaner Production, 2015Co-Authors: Juferi Idris, Ahmad Amiruddin Mohd Ali, Izzudin Ibrahim, Mohd Ridzuan Othman, Yoshito Andou, Yoshihito Shirai, Mohd Ali HassanAbstract:Charcoal production with higher heating value (HHV) requires high capital investment and high energy requirement for large scale production. In this study, charcoal production under self-sustained carbonization from oil palm biomass was proposed and tested at pilot scale, whereby temperature and exhaust gas flow rate were monitored but not controlled. This proposed system under self-sustained carbonization, whereby oil palm biomass is combusted to provide the heat for carbonization in inadequate oxygen is preferable to the industry due to its simplicity, ease of operation and low energy requirement. Moreover, the Gaseous Emissions are below the permitted level set by the environmental authorities. The considerable HHV obtained was between 23 and 25 MJ/kg with low Gaseous Emissions. The results obtained are acceptable and comparable to other studies on oil palm biomass conducted under controlled conditions with electrical heating elements.
Antoni Sanchez - One of the best experts on this subject based on the ideXlab platform.
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Filling in sewage sludge biodrying gaps: Greenhouse gases, volatile organic compounds and odour Emissions.
Bioresource technology, 2019Co-Authors: Daniel González, Nagore Guerra, Joan Colón, David Gabriel, Sergio Ponsá, Antoni SanchezAbstract:Abstract In the present work, a complete study of the sewage sludge (SS) biodrying technology was conducted at bench-scale, aiming at assessing its performance and providing a valuable insight into the different Gaseous Emission patterns found for greenhouse gases (GHG) and odorant pollutants. As process key parameters, temperature, specific airflow, dynamic respiration index, final moisture content and Lower Calorific Value (LCV) were evaluated. At the end of the biodrying, a product with a 35.9% moisture content and a LCV of 7.1 MJ·kg−1product was obtained. GHGs Emission factor was 28.22 kgCO2eq per Mg of initial mass of dry matter in the SS (DM0-SS). During the biodrying process, maximum odour concentration measured was 3043 ou·m−3 and the estimated odour Emission factor of the biological treatment was 3.10E + 07 ou per Mg DM0-SS. Finally, VOCs were completely identified and quantified. The most abundant VOCs found in the biodrying Gaseous Emissions were terpenes, sulphur-compounds and ketones.
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a systematic study of the Gaseous Emissions from biosolids composting raw sludge versus anaerobically digested sludge
Bioresource Technology, 2013Co-Authors: Caterina Mauliniduran, Adriana Artola, Xavier Font, Antoni SanchezAbstract:Abstract Volatile organic compound (VOC) and ammonia, that contribute to odor pollution, and methane and nitrous oxide, with an important greenhouse effect, are compounds present in Gaseous Emission from waste treatment installations, including composting plants. In this work, Gaseous Emissions from the composting of raw (RS) and anaerobically digested sludge (ADS) have been investigated and compared at pilot scale aiming to provide Emission factors and to identify the different VOC families present. CH4 and N2O Emissions were higher in ADS composting (0.73 and 0.55 kg Mg−1 sludge, respectively) than in RS composting (0.01 kg Mg−1 sludge for both CH4 and N2O). NH3 and VOCs emitted were higher during the RS composting process (19.37 and 0.21 kg Mg−1 sludge, respectively) than in ADS composting (0.16 and 0.04 kg Mg−1 sludge). Significant differences were found in the VOC compositions emitted in ADS and RS composting, being more diverse in RS than ADS composting.
U. Fritze V. Alvensleben - One of the best experts on this subject based on the ideXlab platform.
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Spectral and photometric evolution of young stellar populations: The impact of Gaseous Emission at various metallicities
Astronomy & Astrophysics, 2003Co-Authors: Peter Anders, U. Fritze V. AlvenslebenAbstract:We include Gaseous continuum and line Emission into our galev models for the spectral and photometric evolution of Simple Stellar Populations (SSPs) for various metallicities in the range 0:02 Z=Z 2:5. This allows to extend them to significantly younger ages than before. They now cover the age range from 4 Myr all through 14 Gyr. We point out the very important contributions of Gaseous Emission to broad band fluxes and their strong metallicity dependence during very early evolutionary stages of star clusters, galaxies or subgalactic fragments with vigorous ongoing star formation. Emission- line contributions are commonly seen in these actively star-forming regions. Models without Gaseous Emission cannot explain their observed colors at all, or lead to wrong age estimates. We use up-to-date Lyman continuum (=Lyc) Emission rates and decided to use recent empirical determinations of Emission line ratios relative to H for subsolar metallicities. We justify this approach for all situations where no or not enough spectral information is available to determine all the parameters required by photoionization models. The eects of Gaseous line and continuum Emission on broad band fluxes are shown for dierent metallicities and as a function of age. In addition to the many filter systems already included in our earlier models, we here also include the HST NICMOS and Advanced Camera for Surveys (=ACS) filter systems.
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spectral and photometric evolution of young stellar populations the impact of Gaseous Emission at various metallicities
arXiv: Astrophysics, 2003Co-Authors: Peter Anders, U. Fritze V. AlvenslebenAbstract:We include Gaseous continuum and line Emission into our GALEV models for the spectral and photometric evolution of Simple Stellar Populations (SSPs) for various metallicities in the range 0.02 <= Z/Zsun <= 2.5. This allows to extend them to significantly younger ages than before. They now cover the age range from 4 Myr all through 14 Gyr. We point out the very important contributions of Gaseous Emission to broad band fluxes and their strong metallicity dependence during very early evolutionary stages of star clusters, galaxies or subgalactic fragments with vigorous ongoing star formation. Emission-line contributions are commonly seen in these actively star-forming regions. Models without Gaseous Emission cannot explain their observed colors at all, or lead to wrong age estimates. We use up-to-date Lyman continuum Emission rates and decided to use recent empirical determinations of Emission line ratios relative to Hbeta for subsolar metallicities. We justify this approach for all situations where no or not enough spectral information is available to determine all the parameters required by photoionization models. The effects of Gaseous line and continuum Emission on broad band fluxes are shown for different metallicities and as a function of age. In addition to the many filter systems already included in our earlier models, we here also include the HST NICMOS and Advanced Camera for Surveys (= ACS) filter systems.
Esa Alakoski - One of the best experts on this subject based on the ideXlab platform.
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from wood pellets to wood chips risks of degradation and Emissions from the storage of woody biomass a short review
Renewable & Sustainable Energy Reviews, 2016Co-Authors: Esa Alakoski, Miia Jamsen, David Agar, Elina Tampio, Margareta WihersaariAbstract:The compounds in stored woody biomass degrade as a result of chemical and/or biological processes during storage. These processes produce Gaseous Emissions. Recent studies concerning Gaseous Emissions from wood pellet storages are reviewed herein. The applicability of the results from pellet research to wood chips is discussed. Thorough scientific understanding on the storage phenomena of wood chips is extremely important as the threat of climate change and the need to reduce greenhouse gas Emissions have led to an increased need to large scale wood chip storage to ensure supply. Typically the gases produced from stored woody biomasses are carbon monoxide (CO), carbon dioxide (CO2), methane (CH4), and other volatile hydrocarbons e.g. aldehydes and terpenes. CO2 and CH4 are greenhouse gases with high global warming potential. Chemical degradation via auto-oxidation of fats and fatty-acids seems to be the dominant mechanism for off-gassing from stored wood pellets, whereas biological processes are mainly responsible for the Gaseous Emission from wood chips. In confined storage spaces Gaseous Emissions may lead to oxygen depletion. Oxygen depletion together with a high CO concentration poses a serious health risk for those working in such conditions. The degradation processes also result in dry matter losses and in spontaneous heating and in the worst case, especially in large piles, spontaneous ignition of the stored material. Thorough and systematic scientific studies on degradation processes and their effects are needed in order to understand and minimise risks from large scale wood chips storage to human health, environment and property.