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Journal articles on the topic 'Composition biomasse'
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1
Togouet, S. H. Zébazé, T. Njiné, N. Kemka, M. Nola, S. Foto Menbohan, D. Niyitegeka, P. Ngassam, and C. Boutin. "Composition et distribution spatio-temporelle des protozoaires ciliés dans un petit lac hypereutrophe du Cameroun (Afrique centrale)." Revue des sciences de l'eau 19, no. 3 (September 13, 2006): 151–62. http://dx.doi.org/10.7202/013535ar.
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RésuméLa composition et la distribution spatio-temporelle des ciliés du Lac Municipal de Yaoundé (Cameroun) ont été analysées d’avril à décembre 1997, en relation avec des paramètres physico-chimiques du milieu. Trois stations pélagiques et l’herbier littoral ont été échantillonnés. 58 espèces de protistes ciliés ont pu être identifiées, parmi lesquelles environ 60 % d’espèces littorales et périphytiques et 37 % d’espèces pélagiques. Les espèces les plus courantes sont les espèces pélagiquesUronema nigricansetColeps hirtus. L’abondance saisonnière des ciliés a atteint une valeur maximale de 21 800 ind•L-1, les valeurs les plus élevées étant enregistrées dans la couche trophogène du lac, particulièrement au cours de la grande saison des pluies. Les variations de la biomasse totale des ciliés sont plus faibles, avec des maxima correspondant également aux fortes pluies. Les espèces dominantes en matière de biomasse sontProrodon africanum,Coleps hirtusetUronema nigricans. Enfin, les fluctuations saisonnières de l’abondance et de la biomasse des ciliés sont discutées en relation avec les paramètres environnementaux, parmi lesquels le régime pluvial tient apparemment un rôle central.
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Diop, Amadou Tamsir. "La gestion des parcours de l'aire d'influence du forage de Tatki : relations entre données de végétation, taux d'exploitation et transhumance." Revue d’élevage et de médecine vétérinaire des pays tropicaux 45, no. 1 (January 1, 1992): 81–90. http://dx.doi.org/10.19182/remvt.8962.
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Cette étude vise à acquérir une meilleure connaissance de l'utilisation des parcours en saison sèche et de la mobilité des éleveurs en Zone Sylvopastorale du Sénégal. Elle s'est déroulée d'octobre 1989 à juillet 1990 au niveau de l'aire d'influence du forage de Tatki. Dans un premier temps, ont été déterminés les relations entre le taux d'exploitation des parcours et différents paramètres du milieu (biomasse et composition floristique de la strate herbacée en fin de saison des pluies, distance au forage et type de sol). Par la suite, l'incidence de la biomasse, de la composition floristique de la végétation herbacée et du taux d'exploitation des parcours sur les déplacements des éleveurs est envisagée. En conclusion, les limites de l'étude pour l'élaboration de modèles d'utilisation des parcours et pour une meilleure connaissance de la mobilité pastorale sont définies.
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Elfaki, Elsadig Ahmed, Slim Saïdi, Ali Mohamed Adeeb, and Alexandre Ickowicz. "Water harvesting model for improved rangeland productivity in Butana, Sudan." Revue d’élevage et de médecine vétérinaire des pays tropicaux 68, no. 2-3 (March 25, 2016): 143. http://dx.doi.org/10.19182/remvt.20601.
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La biomasse aérienne et la composition floristique des pâturages du Butana au Soudan ont été évaluées en 2006 à partir d’enquêtes de terrain sur 25 sites. La mise en œuvre de l’indice perpendiculaire de végétation, issu du traitement de l’image Spot, a été couplée aux enquêtes de terrain afin de cartographier la distribution spatiale de la production de biomasse (kg ha-1). La carte des précipitations de la région a été établie à partir des données météorologiques de la saison et du modèle numérique d’élévation. Le coefficient d’efficacité pluviale de la région, qui est le quotient de la production primaire annuelle (kg matière sèche ha-1) d’une saison par la quantité de pluie (mm) dans la même saison, a été utilisé comme indicateur de la dégradation et de la désertification des parcours du Butana. Afin de tester l’efficacité des techniques de récupération de l’eau sur la production de biomasse, deux saisons d’expérimentation ont été nécessaires (2006 et 2007). Les résultats obtenus ont permis de simuler le potentiel de production de biomasse à travers un modèle général impliquant conjointement les données télédétectées, les mesures de biomasse des sites de récolte ainsi que la quantité d’eau de surface reçue par chaque site.
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Igoud, Sadek, Insaf Tou, Salim Kehal, Noura Mansouri, and Abdelkader Touzi. "Première Approche de la Caractérisation du Biogaz Produit à Partir des Déjections Bovines." Journal of Renewable Energies 5, no. 2 (December 31, 2002): 123–28. http://dx.doi.org/10.54966/jreen.v5i2.891.
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La production du biogaz est une technique largement répandue dans le monde. Très riche en biométhane, ce gaz permet l’approvisionnement énergétique renouvelable notamment des zones agricoles et rurales où la biomasse organique est abondante. Dans ce contexte, la Division Biomasse prospecte la filière de la production du biogaz à partir des déchets organiques qui reste une source énergétique non exploitée en Algérie. L’article proposé présente une première approche de cette prospection qui consiste en l’installation d’un digesteur expérimental d’une capacité de 800 litres. Son utilisation pour une première biométhanisation mésophile a permis de produire 26,898 m3 de biogaz à partir de 440 Kilogrammes de bouses de vaches durant 77 jours. La composition moyenne du biogaz est de 61% de méthane et de 35,65% de gaz carbonique.
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Szelag-Wasielewska, E. "Distribution du picoplancton autotrophe dans la zone pélagique d'un lac méromictique (Lac Czane, Pologne)." Revue des sciences de l'eau 18 (April 12, 2005): 1–11. http://dx.doi.org/10.7202/705572ar.
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La composition, l'abondance et la biomasse de la communauté du picoplancton autotrophe (PPA, 0,2-2 m) ont été examinées dans un lac situé en Pologne et récemment considéré comme méromictique, le lac Czarne. Les échantillons d'eau ont été prélevés tous les mètres dans la colonne d'eau, en mars et en juillet 1998. Pendant ces deux dates, le PPA se caractérisait par des changements significatifs de densité dans la colonne d'eau. Au printemps, l'abondance la plus forte a été observée à 9 m (2,1·105 cellules·mL-1) tandis qu'en été elle est observée à 5 m (3,1·105 cellules·mL-1). À toutes les profondeurs, le PPA était dominé par des Cyanobactéries. Au printemps, dominent les cellules libres de picocyanobactéries, contrairement à l'été où les cellules coloniales étaient prépondérantes. La contribution des cellules eucaryotes était faible en termes d'abondance (<20%) et bien plus élevée en termes de biomasse, avec une valeur moyenne de 33% au printemps. La biomasse moyenne du PPA était plus élevée au printemps (12 µgC·L-1) qu'en été (8 µgC·L-1) et des différences nettes sont observées entre les saisons dans sa distribution en fonction de la profondeur.
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MANGAZA, Lisette, Jean-Remy MAKANA, Wannes HUBAU, Denis SONWA, Germain BATSI, and Adeline FAYOLLE. "Impacts du changement d’utilisation des terres sur la biomasse et la diversité dans le paysage forestier de la réserve de biosphère de Yangambi en République démocratique du Congo." BOIS & FORETS DES TROPIQUES 353 (October 1, 2022): 61–73. http://dx.doi.org/10.19182/bft2022.353.a36836.
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Les forêts tropicales de la République démocratique du Congo sont menacées par la déforestation et la dégradation forestière, qui affectent la structure et la diversité arborée. Cette étude a pour objectif de quantifier les pertes de biomasse et de diversité liées à la déforestation et à la dégradation, en se concentrant sur la réserve de biosphère de Yangambi. Quatre parcelles de 50 m x 50 m ont été inventoriées dans chacun des huit types d’utilisation des terres identifiés : la forêt mature mixte, la forêt mature à Gilbertiodendron dewevrei, les champs des cultures vivrières, les jachères (5 à 10 ans), les forêts secondaires (20 à 40 ans), les plantations de cacaoyers, les plantations de caféiers et les plantations de palmiers à huile. Les stocks de biomasse dans les forêts matures s’élèvent à environ 400 et 380 Mg/ha respectivement pour la forêt à G. dewevrei et la forêt mixte. Les résultats montrent que la forêt mature perd 50, 70 et 90 % de sa biomasse aérienne quand elle est convertie en plantations de cacaoyers, caféiers et palmiers, respectivement, et la quasi-totalité (99 %) lorsqu’elle est convertie en champs de cultures vivrières ; mais quand le champ est abandonné, la biomasse se reconstitue progressivement à 7,5 % après 5 à 10 ans et à 38,8 % après 20 à 40 ans. La diversité est aussi impactée par la conversion, et, bien que la richesse spécifique semble se reconstituer plus rapidement que la biomasse, la composition est fondamentalement modifiée. Ces résultats fournissent des informations essentielles pour quantifier les impacts des solutions « naturelles » pour lutter contre le changement climatique : la protection des forêts matures, l’amélioration de la gestion forestière et le reboisement ; même si l’approche doit être étendue à plus grande échelle.
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Loubota Panzou, Grace Jopaul. "Biomasse et stocks de carbone en Afrique centrale : importance de l’allométrie des arbres." BOIS & FORETS DES TROPIQUES 343 (March 31, 2020): 85–86. http://dx.doi.org/10.19182/bft2020.343.a31853.
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Quantifier les stocks de biomasse et de carbone dans les forêts tropicales est essentiel pour la mise en œuvre des stratégies d’atténuation des changements climatiques, et notamment le mécanisme de réduction des émissions dues à la déforestation et la dégradation des forêts. Les scientifiques s’accordent aujourd’hui à utiliser une équation allométrique de biomasse générale, combinée à une allométrie hauteur-diamètre ajustée sur des données locales non destructives. Or, l’allométrie des arbres varie entre les espèces et stratégies fonctionnelles d’une part, entre les types de forêts et conditions du milieu d’autre part. L’objectif de cette thèse de doctorat était d’étudier les variations de l’allométrie des arbres entre espèces coexistantes, et entre sites et types de forêts, en vue d’améliorer les estimations de la biomasse et des stocks de carbone en Afrique centrale. Les variations des allométries hauteur-diamètre et houppier-diamètre ont été rapportées pour les 45 espèces d’arbres coexistantes d’un site représentatif des forêts semi-décidues à Celtis du nord du Congo. Les relations entre les traits architecturaux dérivés à partir des allométries spécifiques aux espèces et les traits fonctionnels ont mis en évidence un continuum d’espèces entre les espèces de grande taille dominant la canopée et les espèces de petite taille dominant le sous-bois. Les espèces d’arbres de grande taille étaient exigeantes en lumière, dispersées par le vent, décidues avec une large contribution à la biomasse forestière, alors que les espèces d’arbres de petite taille étaient tolérantes à l’ombrage, dispersées par les animaux, sempervirentes et plus abondantes en densité de tiges. Les variations des allométries hauteur-diamètre et houppier-diamètre ont été également montrées entre les types de forêts en Afrique centrale. Ces tendances étaient en outre confirmées pour les espèces communes entre les types de forêts, suggérant un contrôle environnemental sur les variations de l’allométrie des arbres. Des attributs architecturaux dérivés des allométries spécifiques aux sites, en plus des attributs plus classiques de structure et de composition, ont pu être dérivés et reliés aux variations spatiales de la biomasse et des stocks de carbone. Cette thèse de doctorat a fourni de nouvelles données pour les futures cartes de biomasse dans le cadre du suivi du carbone forestier en Afrique centrale.
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Lavoie, I., F. V. Warwick, P. Reinhard, and J. Painchaud. "Effet du débit sur la dynamique temporelle des algues périphytiques dans une rivière influencée par les activités agricoles." Revue des sciences de l'eau 16, no. 1 (April 12, 2005): 55–77. http://dx.doi.org/10.7202/705498ar.
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Le périphyton de la rivière Boyer Nord, une rivière affectée par les activités agricoles dans le sud du Québec (Canada), a été échantillonné toutes les deux semaines de la mi-mai à la fin septembre 1999 afin d'évaluer son évolution temporelle et d'identifier les variables potentielles qui le contrôlent. Les résultats montrent la grande variabilité temporelle de la biomasse périphytique (poids sec organique et chlorophylle a) et de la structure de la communauté de diatomées. La communauté d'algues benthiques dans la rivière Boyer était principalement composée de diatomées (Nitzschia, Cocconeis, Cymbella, Cyclotella), d'algues vertes (Scenedesmus, Pediastrum, Cosmarium, Closterium) et de cyanobactéries (Phormidium, Oscillatoria, Merismopedia). La pointe de débit observée durant la semaine précédant l'échantillonnage était fortement corrélée à plusieurs variables physico-chimiques (N-total, NH3-N, NO3-N, P-total, turbidité) et était le plus fortement corrélée aux changements temporels de la biomasse. La biomasse (chlorophylle a et poids sec organique) était négativement corrélée au phosphore total, ce qui reflète la relation avec le débit. Les changements temporels dans la composition spécifique des diatomées étaient régis par différentes variables physico-chimiques, selon les limites de tolérances et la valence écologique des espèces. Les algues périphytiques de cette communauté ont réagi aux variations de l'environnement à l'intérieur d'une période de 2 semaines puisque des changements majeurs dans la structure de l'assemblage de diatomées ont été observés lors de chaque échantillonnage. Ces observations montrent la forte variabilité de la biomasse et de la structure de la communauté périphytique dans les rivières enrichies par les éléments nutritifs et souligne l'influence majeure du débit dans ce type d'environnement.
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Jalal, W., B. Pinel-Alloul, and G. Méthot. "Suivi à moyen terme des impacts écologiques des feux et des coupes forestières sur la communauté zooplanctonique des lacs de l'écozone boréale." Revue des sciences de l'eau 18 (April 12, 2005): 221–48. http://dx.doi.org/10.7202/705585ar.
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Cet article vise à évaluer les effets à moyen terme des feux et des coupes de forêt sur la biomasse, la richesse spécifique et la composition du zooplancton des lacs de la forêt boréale au Québec. L'étude a été réalisée durant trois ans (1996-1998) après les perturbations sur 3 sous-ensembles de lacs similaires au niveau de leur morphométrie, incluant 7 lacs naturels non perturbés sur leur bassin versant, 7 lacs affectés par des coupes sur plus de 43% de la surface du bassin versant et 7 lacs affectés par des feux sur plus de 50% de la surface du bassin versant. Notre étude indique que le zooplancton a une forte résilience aux perturbations des lacs de la forêt boréale par les feux et les coupes. Les assemblages d'espèces sont très stables et varient peu entre les lacs naturels et les lacs perturbés. Les Rotifères sont le seul groupe affecté par les perturbations; leur richesse spécifique et leur biomasse sont plus fortes dans les lacs perturbés que dans les lacs naturels. Les feux ont un effet d'eutrophisation plus marqué que les coupes. Dans les lacs affectés par les feux, les apports accrus de nutriments favorisent la croissance du phytoplancton puis des rotifères. Toutefois, dans les lacs affectés par les coupes, la forte couleur de l'eau due aux apports accrus en carbone organique dissous est un facteur limitant, et la hausse du phytoplancton et des rotifères est moins accentuée. La richesse spécifique et la biomasse des Crustacés (Cladocères, Copépodes Calanoïdes et Cyclopoïdes) ne varient pas avec les perturbations. Sur l'ensemble du suivi, le niveau de perturbation n'est pas fortement relié aux changements dans la biomasse des groupes taxinomiques qui s'expliquent plutôt par les variations annuelles de la température de l'eau et des concentrations en chlorophylle a.
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Weaver, Peter L. "Changements à long terme de structure et de composition d'une forêt primaire humide de basse montagne suite au passage d'ouragans a Puerto Rico." BOIS & FORETS DES TROPIQUES 317, no. 317 (September 1, 2013): 7. http://dx.doi.org/10.19182/bft2013.317.a20525.
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Dacryodes excelsa, espèce arborée connue sous les noms de tabonuco à Puerto Rico et de gommier aux Petites Antilles, domine les sommets de la forêt tropicale humide de basse montagne (selon Beard) de l'archipel des Caraïbes ; où périodiquement les ouragans passent à travers les îles modifiant la structure des massifs forestiers, leur composition en essences et leur dynamique. Au nord-est de Puerto Rico, l'étude chronologique post-ouragans menée entre 1946 et 2010 a permis de suivre les modifications de la végétation sur une parcelle de 0,40 hectare à 380 metres d'altitude dans la forêt expérimentale de Luquillo. Celle-ci a montré : (1) la défoliation, la casse et les chablis provoqués par le vent induisant une mortalité immédiate entraînent une déstructuration de forêt en perte du nombre de tiges, de hauteur des arbres et de biomasse ; (2) la mortalité différée de d'autres arbres blessés s'accompagne d'un rapide et abondant recrutement de Cecropia schreberiana et d'espèces cicatricielles, augmentant le nombre de tiges dans la forêt ; (3) une accélération de la croissance en diamètre et l'accumulation de la biomasse pendant une vingtaine d'années après l'ouragan, suivie du déclin de leur ratio ; (4) un très fort taux de survie après l'ouragan et une augmentation de la vitesse de croissance en diamètre de Dacryodes excelsa ; (5) toujours suite à l'ouragan, une augmentation de la richesse en espèces pendant une période de 20 ans au cours de laquelle les espèces primaires et secondaires grandissent ensemble, suivie dune chute d'abondance liée la concurrence ; (6) enfin, des conditions d'évolution asymptotiques aussi bien pour les tiges et la biomasse que pour le nombre d'espèces, après plus de 40 ans. En outre, d'autres études connexes menées dans des types de forêts semblables ont montré que les ouragans et les coupes intensives induisent des réactions de croissance comparables. Cette étude s'avère être d'intérêt régional puisque la forêt humide de basse montagne de Puerto Rico partage des conditions environnementales semblables ainsi que les mêmes essences forestières avec les montagnes des Antilles.
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Damiri, L., M. Alaoui Mhamdi, and J. Bahhou. "Dynamique des populations microphytobenthiques couplée à leur composition biochimique au sein du réservoir Allal El Fassi (Maroc)." Revue des sciences de l'eau 15, no. 1 (April 12, 2005): 101–9. http://dx.doi.org/10.7202/705439ar.
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L'étude du métabolisme des populations microphytobenthiques par le biais des principaux constituants cellulaires à savoir les glucides, les protéines et les lipides a été réalisée du mois d'août 1996 au mois de juillet 1997 au sein du réservoir Allal El Fassi, situé sous climat semi-aride. Les résultats issus d'un échantillonnage sur substrats artificiels permettent de montrer que : - la température, l'oxygène, l'azote et le phosphore influencent l'orientation métabolique des populations microphytobenthiques ; - les plus fortes concentrations en glucides, en protéines et en lipides correspondent à des populations estivales ; - les lipides sont susceptibles de fournir une estimation satisfaisante de la biomasse microphytobenthiques ; - le métabolisme du microphytobenthos s'oriente vers la synthèse préférentielle des protéines.
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Weaver, Peter L. "Distribution des essences et structure forestière selon les gradients environnementaux de la forêt naine des monts Luquillo à Puerto Rico." BOIS & FORETS DES TROPIQUES 306, no. 306(4) (December 1, 2010): 33. http://dx.doi.org/10.19182/bft2010.306.a20429.
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Onze groupes de trois placettes stratifiées selon leur exposition (face au vent/sous le vent), la topographie (arête, pente ou ravin) et l'altitude, entre 880 et 1000 mètres environ, ont servi un échantillonnage de la structure forestière et de la composition floristique de la forêt naine des monts Luquillo Puerto Rico. La densité des tiges face au vent est sensiblement plus importante sur les pentes, et pour l'ensemble des topogra-phies, que sous le vent. Le couvert sous le vent est sensiblement plus élevé sur les pentes, et pour l'ensemble des topographies, que face au vent. En outre, dans tous les sites, la densité totale médiane décroît mesure que l'on descend de l'arête vers les pentes et jusqu'aux ravins, alors que cette tendance s'inverse pour la hauteur moyenne de l'ensemble du couvert. Pour les deux types d'exposition, la biomasse est plus importante sur les arêtes et les pentes que dans les ravins. La biomasse est plus importante sous le vent que face au vent pour l'ensemble des topographies; cependant, aucune relation biomasse n'est significative. Tabebuia rigida Urban est l'essence la plus abondante, avec plus de 23% des 3 619 tiges recensées, et Eugenia borinquensis Britton la plus largement présente, sur 90% des pla-cettes. La moitié des 42 essences recensées totalisent moins de 2% de l'ensem-ble des tiges. La forêt naine, adaptée la survie sous des conditions rudes, évolue sous l'influence de facteurs édaphiques, climatiques et physiologiques. Ces forêts naines apportent de nombreux bénéfices: elles représentent un habitat critique pour de nombreuses espèces de faune et flore endémiques, renferment de précieuses ressources en eau et offrent des paysages panoramiques et bon nombre d'opportunités récréatives. (Résumé d'auteur)
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Bounou Madja, Rabiou, Maman Kamal Abdou Habou, Issoufa Idrissa, Ibrahim Djibo Moussa, Boube Morou, and Ali Mahamane. "EVALUATIONS DE LA BIOMASSE FOURRAGERE FOLIAIRE ET DE LA COMPOSITION CHIMIQUE DES FEUILLES DUN LIGNEUXFOURRAGER SAHELIEN :MAERUA.CRASSIFOLIAFORSSK." International Journal of Advanced Research 11, no. 12 (December 31, 2023): 879–89. http://dx.doi.org/10.21474/ijar01/18054.
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A woodyfodderspecies, M. crassifoliaisparticularlysoughtafter by animals, especiallyduringthe dryseason. The overall objective of thisstudyis to evaluate the leaf production and the chemical composition of M. crassifolialeaves in the rural commune ofOurafane in the southernsahelianarea.Leaf production wasestimated using the standard branchmethodcombiningallometricequationswithdendrometricparameters. The phytochemicalstudy of the leaveswascarried out through the collection of 10 leafsamples of 50g each, takenfrom 10 individuals. Thesesampleswereanalyzedat the InternationlCropsResearch Institute for the Semi-AridTropics (ICRISAT)SoilAnalysislaboratory. Thus, leaf production wasestimatedusing the exponentialprediction model from the circumference of the trunk of the shrub:Pf = 0.0599e15.802CT (Pf, Leaf production in KgMS and CT, trunkcircumference in m). Leaf production is 23.65Kg DM/ha. The leaves are essentially made up of organicmatter (68.76±1.77%) and are rich in crudeproteins (26.63±1.66% MAT on average). Theyalsocontainminerals, the main onesbeing potassium (0.45±0.56) and phosphorus (0.13±0.02). The results of thisstudywill not onlycontribute to better management of the species but also and above all, theycanbeused by the livestock service for a rapid and reliableassessment of woodyfodder production.
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Gérard, Imani Mugisho, Zapfack Louis, Mangambu Mokoso Jean De Dieu, Penedimanja Pancrace, Mwanga Mwanga Ithe Jean-Claude, Boyemba Faustin, and Amani Christian. "Caractérisations Structurale, Floristique Et Biomasse Ligneuse Du Peuplement À Hagenia abyssinica Du Parc National De Kahuzi-Biega (Rift Albertin, RDC)." European Scientific Journal, ESJ 12, no. 15 (May 30, 2016): 189. http://dx.doi.org/10.19044/esj.2016.v12n15p189.
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Hagenia abyssinica is a characteristic species of mountain forests in the Albertine Rift. In Kahuzi Biega National Park, the species is found between 2000 and 2600 m altitude. This study intended to characterize Hagenia monospecific forest by providing an account for its floristic composition, structure and biomass. Data were collected from 9 different plots of 1 hectare each located in 3 different sites (Tshivanga 2000-2250m asl; Mugabe and Kasirusiru 2400-2600m asl). Parameters including tree diameter ≥ 10cm, height, dead individuals and young shoots of Hagenia abyssinica were wetting the plot. The results showed that species richness was significantly low, varying between 8-24 species (p < 0.05, Df = 35); while the specific density was 565 ± 121 individuals. The Richness decreased with the increment of the species density of Hagenia. The similarity analysis revealed the influence/impact of the site/altitude on the species composition. The diametric structure showed a regressive dynamism within the population found between 2000 and 2200 m altitude, in which Hagenia specimens were replaced by the specimens of secondary forest species such as Sapium ellipticum, Macaranga neomilbraediana, Neoboutonia macrocalyx. Whereas, between 2400-2600 m altitude, there was a progressive dynamism with several Hagenia young shoots, with no mortality (χ2 = 487, p < 0.001). The average woody biomass was estimated at 108t / ha. This increased as Hagenia density decreased and vegetation became heterogeneous. Human disturbance and climate change effects in the region, could be the causes of variability observed in this population in the Kahuzi-Biega National Park.
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ROBERTA DA SILVA FERREIRA, VITÓRIA, VIVIAN MIDORI TAKAHASHI, PEDRO HENRIQUE GONZALEZ DE CADEMARTORI, MAYARA ELITA CARNEIRO, and DIMAS AGOSTINHO DA SILVA. "QUALIDADE ENERGÉTICA DE RESÍDUOS MADEIREIROS PARICÁ E PINUS." ENERGIA NA AGRICULTURA 36, no. 2 (August 12, 2021): 230–38. http://dx.doi.org/10.17224/energagric.2021v36n2p230-238.
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QUALIDADE ENERGÉTICa de resíduos madeireiros paricá e pinus VIVIAN MIDORI TAKAHASHI1, VITÓRIA ROBERTA DA SILVA FERREIRA1, PEDRO HENRIQUE GONZALEZ DE CADEMARTORI1,2, MAYARA ELITA CARNEIRO2, DIMAS AGOSTINHO DA SILVA1,2 1 Programa de Pós-Graduação em Engenharia Florestal (PPGEF), Universidade Federal do Paraná, Av. Prefeito Lothário Meissner, 632 - Jardim Botânico, Curitiba - PR, 80210-170, viviantakahashi@hotmail.com; victoria_roberta19@hotmail.com 2 Departamento de Engenharia e Tecnologia Florestal (DETF), Universidade Federal do Paraná, Av. Prefeito Lothário Meissner, 632 - Jardim Botânico, Curitiba - PR, 80210-170, pedroc@ufpr.br; mayaraecarneiro@gmail.com; dimas.agostinho.silva@gmail.com RESUMO: O presente trabalho investigou a qualidade energética de resíduos de Paricá e Pinus. Para tal, foram investigadas as propriedades químicas, térmicas e energéticas das biomassas de paricá e pinus por meio da química elementar, química macromolecular e química imediata, além da obtenção do poder calorífico por meio de normas regulamentadoras. Além disso, realizou-se análise termogravimétrica em ambiente inerte e oxidativo para simular o comportamento das biomassas em processos de pirólise e combustão. Ambas as biomassas apresentaram teor de carbono próximo à 45%. O teor de lignina para a paricá e do pinus foi de 26 e de 31%, respectivamente. A madeira de paricá apresentou teor de cinzas cerca de três vezes maior que o pinus, enquanto o poder calorífico foi estatisticamente igual. Qualitativamente, as curvas termogravimétricas mostraram um comportamento de degradação similar, porém, denotou-se uma maior massa residual para a biomassa de pinus. Portanto, concluiu-se que a biomassa de paricá apresenta potencial como fonte alternativa para a geração de energia, porém, ressalta-se que potenciais rotas de conversão termoquímica devem levar em consideração o maior teor de cinzas da biomassa de paricá em comparação a biomassa de pinus, o que pode causar problemas durante a utilização desta espécie como biocombustível. Palavras-chave: biocombustível, biomassa residual, composição química, energia ENERGY QUALITY OF PARICÁ AND PINE WOOD RESIDUES This work investigated the energy quality of residues of Paricá and Pinus. Chemical, thermal and energetics properties of the biomasses were investigated by means of elemental analysis, macromolecular chemical components, proximate analysis, and high heating value. The thermogravimetry. Was investigated in an inert and oxidative environment to simulate the behavior of the biomasses in both pyrolysis and combustion processes. Both biomasses presented fixed carbon around 45%. The lignin content for paricá and pinus was 26 and 31%, respectively. The paricá wood presented an ash content of about three times higher than the pinus, while the calorific value was statistically equal. Qualitatively, the thermogravimetric curves showed a similar degradation behavior, however, a higher residual mass was denoted for the pinus biomass, showing the possibility of using nontraditional species for this purpose compared to pinus biomass. However, note that potential thermo-chemical conversion routes should consider the higher ash content of paricá biomass compared to pinus biomass, which can cause problems during the use of this species as biofuel. Keywords: biofuel, residual biomass, chemical composition, energy
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Weaver, Peter L. "Reprise précoce de la forêt sèche subtropicale au sud-ouest de Puerto Rico." BOIS & FORETS DES TROPIQUES 310, no. 310 (December 1, 2011): 11. http://dx.doi.org/10.19182/bft2011.310.a20455.
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Un inventaire de la couverture forestière et de la composition florale a été réalisé en 1998, 2003 et 2010 suite à l'élimination des pâturages et brûlis dans les 32 hectares inférieurs de la zone de Tinaja, au sein du refuge national de faune de Laguna Cartagena dans le Sud-Ouest de Puerto Rico. Les inventaires de la forêt sèche subtropicale montrent pour la période de 1998 à 2010 une augmentation de 3,9 fois pour les tiges, 6,7 fois pour les arbres, 3,3 fois pour la surface terrière et de 4,4 fois pour la biomasse, et cela avec des variations notables en fonction des sites. Sur 10 parcelles le long de la limite sud, plus proche de la couverture forestière résiduelle, ont été relevés un nombre plus important de tiges et d'arbres, une surface terrière plus grande et, en général, davantage de biomasse que sur les 22 parcelles du côté nord, et ce durant les trois années d'inventaire. Pour quatre parcelles situées dans des criques et une parcelle bordant une clôture, les valeurs sont également plus élevées que les moyennes respectives pour l'ensemble des 32 parcelles du Tinaja inférieur. Les autres tendances notables relevées pour la période de 1998 à 2010 sont les suivantes : les essences exotiques augmentent en proportion de 70 à 84 % en tiges et de 70 à 86 % en arbres ; le rapport entre tiges et arbres diminue de 2,3 à 1,3 ; Leucaena leucocephala (Lam.) DeWit augmente de 7 à 53 % en tiges et de 14 à 64 % en arbres ; Pilosocereus royenii (L.) Byles & Rowley décroît de 10 à 2 % en tiges et de 7 à 1 % en arbres, en raison surtout d'attaques d'une cochenille des cactus, Hypogeococcus pungens ; enfin, la richesse floristique des essences augmente de 30 à 34. (Résumé d'auteur)
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Kambale Muhindo, Z., F. Tendonkeng, E. Miegoue, and E. Pamo Tedonkeng. "Influence de la fréquence de fauche sur la production de biomasse et la composition chimique du foin de Pennisetum clandestinum." International Journal of Biological and Chemical Sciences 12, no. 3 (November 9, 2018): 1459. http://dx.doi.org/10.4314/ijbcs.v12i3.31.
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Duru, M., and I. Calvière. "Effets des niveaux de nutrition en phosphore et en azote et de la composition botanique de communautés prairiales sur l'accumulation de biomasse au printemps." Agronomie 16, no. 4 (1996): 217–29. http://dx.doi.org/10.1051/agro:19960402.
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ÉMILE, J. C., and Y. BARRIÈRE. "Effets de la teneur en grain de l’ensilage de maïs sur les performances zootechniques de vaches laitières." INRAE Productions Animales 5, no. 2 (May 29, 1992): 113–20. http://dx.doi.org/10.20870/productions-animales.1992.5.2.4225.
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Les performances zootechniques de vaches laitières alimentées avec un ensilage de maïs appauvri en épis lors de la récolte ont été comparées à celles de lots témoins recevant l’ensilage normal. En conditions d’apports énergétiques proches de la satisfaction des besoins (3 essais), la réduction de la teneur en grain de 50 à 44 % de la matière sèche n’a eu d’incidence majeure ni sur les quantitées ingérées, ni sur les productions laitières (22,9 et 22,8 kg de lait brut, en moyenne des essais, respectivement pour les lots appauvris et normaux) ou les reprises de poids. Lorsque les apports énergétiques étaient insuffisants (1 essai), on a observé une dégradation des taux butyreux et protéiques. Les estimations de valeurs énergétiques de ces ensilages, fournies par diverses méthodes (composition de la plante, digestibilité in uiuo, digestibilité in vitro par des enzymes ou du jus de rumen), ne permettaient pas de prédire ces résultats. L’appauvrissement en épis s’est traduit par une meilleure utilisation par l’animal de la partie non grain du maïs (0,71 UFL contre 0,66 UFL dans nos conditions). Il semble ainsi possible pour le sélectionneur d’améliorer notablement le rendement en biomasse de cette culture destinée à l’alimentation des vaches laitières en acceptant une diminution de la teneur en grain qui ne serait finalement pas préjudiciable à la qualité.
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Akinola, J. A., A. Larbi, J. A. Odedire, O. A. Aderinola, C. A. Lakpini, J. T. Amodu, J. R. Tanko, and A. Musa. "Effects of NPK Fertilizer application and plant density on forage yield and chemical composition of wild sunflower (Tithonia diversifolia)." Nigerian Journal of Animal Production 50, no. 1 (December 6, 2023): 46–60. http://dx.doi.org/10.51791/njap.v50i1.3903.
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A study was conducted in 2017 and 2018, in the Forest Zone of southwestern Nigeria, to evaluate the yield and chemical composition of wild sunflower (Tithonia diversifolia) fertilized with compound fertilizer (20N:10P2O5:10K2O), under different planting densities. Seedlings of 20-day old Tithonia diversifolia were transplanted on a site, in a split plot arrangement, with fertilizer application at 0, 50, 100, 200 and 400kg/ha, using a planting density of 83.3 ×103, 166.7 ×103, 222 ×103, 333 ×103, 500 ×103, and 1000 ×103 plants/ha. After 114-116 days of growth, the plants were harvested and analyzed for proximate composition. The highest whole plant DM yield occurred at 400 kg/ha fertilizer level and a population density of 333×103 plants/ha. Leaf and inflorescence DM yields peaked at 400 kg/ha fertilizer application while the best leaf yield and inflorescence response to density resulted from 333 ×103 plants/ha, regardless of year under investigation. Overall fertilizer treatments and across densities, the leaf and inflorescence fractions recorded 16.88-22.92 % and 14.38-15.10% CP, 12.09-13.24 % and 21.25-23.60 % CF, 4.89-5.60 % and 3.67-4.72 % EE and 13.42-14.84 % and 6.27-7.53 % ash, respectively. Results obtained suggest that the high biomass yield of Tithonia diversifolia combined with its satisfactory nutrient levels, qualifies the plant as a potential suitable feed supplement source for ruminant livestock.
Une étude a été menée en 2017 et 2018, dans la zone forestière du sud-ouest du Nigéria, pour évaluer le rendement et la composition chimique du tournesol sauvage (Tithonia diversifolia) fertilisé avec un engrais composé (20N:10P2O5:10K2O), sous différentes densités de plantation. Des semis de Tithonia diversifolia âgés de 20 jours ont été transplantés sur un site, dans une disposition en parcelles divisées, avec une application d'engrais à 0, 50, 100, 200 et 400 kg/ha, en utilisant une densité de plantation de 83,3 × 103, 166,7 × 103, 222. ×103, 333 ×103, 500 ×103 et 1 000 ×103 plants/ha. Après 114 à 116 jours de croissance, les plantes ont été récoltées et analysées pour déterminer leur composition immédiate. Le rendement le plus élevé en matière sèche de plante entière a été obtenu avec un niveau d'engrais de 400 kg/ha et une densité de population de 333 × 103 plantes/ha. Les rendements en matière sèche des feuilles et des inflorescences ont culminé à 400 kg/ha d'application d'engrais, tandis que le meilleur rendement foliaire et la meilleure réponse de l'inflorescence à la densité résultaient de 333 × 103 plantes/ha,quelle que soit l'année étudiée. Dans l'ensemble des traitements d'engrais et selon les densités, les fractions de feuilles et d'inflorescences ont enregistré 16,88-22,92 % et 14,38-15,10 % CP, 12,09 13,24 % et 21,25-23,60 % CF, 4,89-5,60 % et 3,67-4,72 % EE et 13,42-14,84 %. et 6,27 à 7,53 % de cendres, respectivement. Les résultats obtenus suggèrent que le rendement élevé en biomasse de Tithonia diversifolia, combiné à ses niveaux de nutriments satisfaisants, qualifie la plante comme une source potentielle de complément alimentaire appropriée pour le bétail des ruminants.
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Baltrėnaitė, Edita, Pranas Baltrėnas, and Donald Huisingh. "Technogenic metallic elements in biomass and their effects on biomass product properties." Journal of Water Supply: Research and Technology-Aqua 68, no. 8 (December 1, 2019): 623–44. http://dx.doi.org/10.2166/aqua.2019.082.
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Abstract Availability of clean water and sustainable management of water are among the 17 global ‘Sustainable Development Goals,’ established by the United Nations. The increasing technogenesis-related pollution causes increases the concentrations of many metallic elements (MEs) throughout the biosphere. The syngenetic bio-incorporation of MEs changes the biomass's chemical and physical composition and impacts the quality of products, e.g. biochar (BC). This has impacts upon BCs potential for adsorption of water pollutants. While direct, engineered modification of BC can improve its adsorption characteristics, the more indirect alterations of BC composition, based on syngenetic elements, also modifies BCs adsorption functionality. The objective of this study was to identify the characteristics of syngenetically accumulated MEs in ligneous biomass on the adsorptive properties of the BCs derived from such modified biomasses. The authors of this paper investigated the syngenetic pathway of MEs into the ligneous biomass and provided an overview of the forms and quantities of MEs in the biomass and their transformation to BC. The early results of the effects of syngenetic MEs on the adsorptive properties of BC from ligneous biomass are presented. The results suggest that additional syngenetical MEs result in increases in the adsorptive properties of the resultant biomass-derived BCs.
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Umrisu, Maria Lurumutin, Redi K. Pingak, and Albert Zicko Johannes. "PENGARUH KOMPOSISI SEKAM PADI TERHADAP PARAMETER FISIS BRIKET TEMPURUNG KELAPA." Jurnal Fisika : Fisika Sains dan Aplikasinya 3, no. 1 (December 16, 2018): 37–42. http://dx.doi.org/10.35508/fisa.v3i1.592.
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ABSTRAK
Briket bioarang merupakan salah satu bahan bakar yang berasal dari biomassa. Biomassa yang digunakan dalam penelitian ini adalah tempurung kelapa dan sekam padi. Penelitian ini bertujuan untuk mengetahui pengaruh variasi komposisi sekam padi dan variasi perekat terhadap parameter fisis briket tempurung kelapa. Hasil penelitian ini menunjukkan nilai densitas, nilai kadar air, nilai porositas dan nilai kadar abu, secara berturut-turut berkisar antara (0.69 - 1.12 ), (3,33% - 7,57%.), (16,66% - 31,88%.), (38,46% - 66,66%.). Analisis menunjukkan bahwa secara umum, komposisi sekam padi berbanding terbalik dengan nilai densitas, nilai kadar air dan nilai kadar abu briket dan berbanding lurus dengan nilai porositas briket. Berdasarkan nilai densitas, nilai kadar air, dan nilai kadar abu briket, dapat disimpulkan bahwa dalam penelitian ini briket dengan komposisi 40% tempurung kelapa dan 60% sekam padi memiliki kualitas yang lebih baik dibandingkan dengan komposisi lainnya.
Kata Kunci : Briket, Tempurung kelapa, Sekam padi, Densitas, Kadar air, Porositas dan Kadar abu.
ABSTRACT
Bio-briquette is one of the fuels that comes from biomass. The biomass used in this research is coconut shell and rice husk. The aims of this research are to know the influence of variation of rice husk composition and thickness variation on physical parameters of shell briquettes. The results of this study indicate that the density, moisture value, porosity and ash values, respectively ranged between (0.69 - 1.12 ), (3,33% - 7,57%.), (16,66% - 31,88%.), (38,46% - 66,66%.). The analysis showed that in general, the composittion of rice husk is inversely proportional to density, moisture value and briquette ash value, otherwise the composition of rice husk is directly proportional briquette porosity value. Based on density value, mositure value and ash value it can be concluded that in this research the quality of briquettes with composition 40% coconut shell and 60% rice husk is better than the other compositions.
Keywords: Briquette, Coconut shell, Rice husk, Density, Water content, Porosity and Ash content.
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Rizkiana, Meisa Legi, Saepulloh Saepulloh, Prima Besty Asthary, and Rahmaniar Mulyani. "Pengaruh Komposisi Air Limbah Industri Kertas sebagai Media Pertumbuhan dan Fotoperiode Terhadap Kultur Spirulina platensis." JURNAL SELULOSA 9, no. 01 (June 30, 2019): 9. http://dx.doi.org/10.25269/jsel.v9i01.268.
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Industri kertas menghasilkan air limbah dari kegiatan produksi dan proses flue gas desulphurization (air limbah wet scrubber). Senyawa nutrisi (senyawa karbon, nitrogen, dan fosfat) yang masih terdapat dalam air limbah terolah dan air limbah wet scrubber belum dimanfaatkan secara optimal dan berpotensi sebagai media pertumbuhan Spirulina platensis. Penelitian dengan variasi komposisi air limbah dan fotoperiode (24 jam terang dan 12 jam terang/12 jam gelap) telah dilakukan dalam skala laboratorium selama 9 hari. Pengukuran pH media, pertumbuhan S. platensis (konsentrasi biomassa, laju pertumbuhan spesifik, dan waktu penggandaan), dan kandungan fikosianin dilakukan setiap hari untuk melihat pengaruh komposisi media dan perlakuan fotoperiode terhadap pertumbuhan S. platensis. Hasil menunjukkan bahwa S. platensis dapat tumbuh dengan baik pada semua komposisi air limbah terolah dan air limbah wet scrubber yang diujicobakan. Konsentrasi biomassa tertinggi sebesar 831 mg/L dan laju pertumbuhan spesifik tertinggi sebesar 0,52 hari-1 dengan waktu penggandaan 0,4 hari diperoleh dari perlakuan fotoperiode 24 jam terang. Komposisi air limbah terolah dan air limbah wet scrubber tidak memberikan pengaruh yang nyata terhadap konsentrasi biomassa, tetapi perbedaan fotoperiode sangat berpengaruh terhadap konsentrasi biomassa sehingga dalam aplikasi skala lapangan perlu mempertimbangkan sistem pencahayaan untuk pertumbuhan S. platensis yang optimal.Kata kunci: Spirulina platensis, media pertumbuhan, fotoperiode, air limbah terolah, air limbah wet scrubberThe Effect of Composition of Paper Industry Wastewater as A Growth Medium and Photoperiod on The Culture of Spirulina platensisAbstractThe paper industry produces wastewater from its production activities and the flue gas desulphurization process (wet scrubber wastewater). Nutritional compounds (carbon, nitrogen and phosphate compounds) which are still in treated wastewater and wet scrubber wastewater have not been utilized optimally and have potential as growth media of Spirulina platensis. Research on wastewater compositions and photoperiod variations (24 hours light and 12 hours light/12 hours dark) was carried out on a laboratory scale for 9 days. Measurements of medium pH, growth of S. platensis (biomass concentration, specific growth rate, and doubling time), and phycocyanin content were carried out every day to study the effect of wastewater composition and photoperiod treatment on the growth of S. platensis. The results showed that S. platensis can grow well on all compositions of treated wastewater and wet scrubber wastewater. The highest biomass concentration of 831 mg/L and the highest specific growth rate of 0.52 days-1 with a doubling time of 0,4 days is obtained from 24-hour light photoperiod treatment. The composition of treated wastewater and wet scrubber wastewater has no significant effect on the biomass concentration but the photoperiod differences greatly influence the biomass concentration so that in the field scale application it is necessary to consider the lighting system for optimal S. platensis growth. Keywords: Spirulina platensis, growth medium, photoperiod, treated wastewater, wet scrubber wastewater
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Siddo, Ibrahim Soumaïla, Mahaman Moustapha Adamou, Abdourahmane Tankari Dan Badjo, and Zaleyha Amadou Bana. "Evaluation de la production du Moringa oleifera Lam. sur substrat constitué de boue de vidange en fonction de la fertilisation et de la dose d’irrigation." International Journal of Biological and Chemical Sciences 15, no. 6 (February 22, 2022): 2417–25. http://dx.doi.org/10.4314/ijbcs.v15i6.14.
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Dans le contexte de développement durable, la gestion des déchets, quelle que soit leur nature occupe une place importante. La non valorisation des boues de la Société d’Exploitation des Eaux du Niger (SEEN) a motivé la réalisation de cette étude. Menée en condition semis contrôlée, elle avait pour objectif d’évaluer la production du Moringa oleifera sur boue de vidange en fonction de deux doses d’irrigation combinées à différents types de fertilisation. Le dispositif expérimental était un split plot à quatre répétitions et deux facteurs: la dose d’irrigation (0,5 L et 1 L) et la composition du substrat (B, BSC, BSE, BC, BS et S). Les paramètres observés sont : le taux de survie, la hauteur des plantules, le nombre de feuilles, le diamètre au collet de la plante, l’élongation racinaire et la biomasse totale. Les résultats ont montré que la dose d’irrigation de « 1 litre » a été plus favorable sur l’ensemble des substrats et que les plants issus des substrats Boue + Sol ; Boue + Sol + Engrais et Boue + Sol + Compost ont donné les meilleurs résultats. Par contre, une forte létalité des plantes sur les substrats composés uniquement de Boue a été observée. Cette boue pourrait être utilisée en agriculture à condition qu’elle soit supplémentée par des fertilisants organiques.
English title: Evaluation of the production of Moringa oleifera Lam. on the substrate based on mud of drain according to the fertilization and the dose of irrigation
In the context of durable context of development, the management of the waste, whatever the nature has an important place. The non-valorisation of the mud of the Niger Society of Exploitation of Water (NSEW) motivated the realization of this research leaded in seedling controlled condition. The research objective is evaluate the production of Moringa oleifera on the mud of drain according to two doses of irrigation combined on different types of fertilization. The experimental device was Split plot of four repetitions and the two factors: the dose of (0.5 L and 1 L) and the composition of the substrate (B, BSC BSE, BC and S). The parameters observed are the rate of survival, the height of the seedling, the number of leaves, the diameter collar of the seedling, the elongation of the roots and the total biomass. The results have showed that the dose of irrigation of 1 L was more favorable on the whole substractes whereas the seeds of substrates mud + Sol, mud + sol + fertilizer and mud + sol + compost had given the best results although a Big lethality of the seedling on the substractes composed only of mud was observed. This mud could be used in agriculture in condition that it may be followed by some organic fertilizers.
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PITOIS, F., and C. BARGUIL. "Cyanobactéries, eutrophisation et changement climatique dans l’Erdre navigable." Techniques Sciences Méthodes 4, no. 4 (April 23, 2021): 61–74. http://dx.doi.org/10.36904/tsm/202104061.
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Le bassin aval de l’Erdre, affluent rive droite de la Loire, subit chaque année des épisodes de proliférations de cyanobactéries (blooms), régulièrement associées à des productions de toxines qui peuvent remettre en question la pratique des activités de loisirs (pêche, nautisme) ou la production d’eau potable. Le syndicat mixte EDENN (Entente pour l’Erdre navigable et naturelle) a mis en place en 2004 un suivi extensif de la qualité des eaux de l’Erdre : mesures in situ, teneurs en nutriments, phytoplancton et cyanobactéries, toxines… Les chroniques disponibles ont été analysées afin d’évaluer si la composition de la flore et la typologie des cyanobactéries ou des toxines avaient évolué au cours des 15 dernières années, quels étaient les facteurs déterminants des proliférations, et comment l’ensemble du système était susceptible d’évoluer dans un contexte de changement climatique. Les résultats montrent que les blooms sont classiquement favorisés par les eaux chaudes et riches en phosphore, mais aussi largement dépendants du taux de renouvellement des eaux et de la fraction d’ammonium dans l’azote total disponible. Après modélisation, les simulations d’évolution montrent que l’augmentation à moyen terme des températures et de l’ensoleillement n’affectera pas significativement l’intensité annuelle des blooms et notamment la concentration en biomasse des cyanobactéries ; en revanche, la fréquence des épisodes les plus intenses augmentera au rythme de celle des étés chauds et/ou secs, qui a presque doublé depuis les années 1980. Ces simulations montrent également que les disponibilités du phosphore et de l’ammonium sont les principaux leviers d’action disponibles pour réduire l’intensité des blooms et compenser les effets activateurs du changement climatique.
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Riyanto, Hendi, Toto Hardianto, Willy Adriansyah, and Gavriel Y. Jeffry. "Studi Termodinamika Pembakaran Kombinasi Batu Bara dan Biomassa Limbah." JMPM (Jurnal Material dan Proses Manufaktur) 5, no. 2 (March 17, 2022): 82–90. http://dx.doi.org/10.18196/jmpm.v5i2.13903.
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Pembakaran bersama batubara dan biomassa di pembangkit listrik tenaga batubara yang ada sedang dipertimbangkan sebagai alternatif yang layak untuk transisi pemanfaatan energi yang tidak terbarukan ke terbarukan. Dalam hal ini, berbagai penelitian telah dilakukan dalam dua puluh tahun terakhir, yang sebagian besar kesimpulan umum adalah bahwa efisiensi boiler menurun sehubungan dengan peningkatan persentase biomassa dalam co-firing, namun studi tambahan dianggap diperlukan, terutama untuk limbah biomassa yang melimpah di Indonesia. Biomassa limbah yang akan digunakan dalam penelitian ini adalah tandan kosong kelapa sawit (TKKS), sekam padi, dan wood pellet yang dihasilkan dari serbuk gergaji. Karakteristik termodinamika pembakaran co-firing yang akan digunakan dalam penelitian ini adalah air-to-fuel ratio (AFR), emisi CO2 pembakaran, dan temperatur nyala adiabatik. Sebuah open source Cool Prop formulasi sifat termodinamika diimplementasikan untuk mengevaluasi sifat termodinamika bahan yang sesuai yang terlibat dalam penelitian ini. Hasil penelitian menunjukkan bahwa AFR menurun dengan bertambahnya komposisi biomassa dalam bahan bakar, dimana laju perubahan masing-masing AFR per persen biomassa adalah -0,018, -0,0406, dan -0,026 untuk campuran batubara-TKKS, batubara-sekam padi, dan batubara-kayu. Adapun karakteristik AFR, emisi karbon dioksida menurun dengan meningkatnya persen massa biomassa dalam komposisi bahan bakar. Laju perubahan CO2 sehubungan dengan persen biomassa dalam komposisi bahan bakar adalah masing-masing -6.3x10-3, -1.12x10-2, dan -6.48x10-3 untuk campuran batubara-TKKS, batubara-sekam padi, dan batubara-kayu. Suhu nyala adiabatik juga menurun sehubungan dengan peningkatan persentase massa biomassa dalam komposisi bahan bakar. Laju perubahan suhu nyala adiabatik dalam K/%biomassa berturut-turut adalah -13,93, -10,70, dan -12,81 untuk campuran TKKS batubara, sekam padi, dan kayu batubara.Co-firing of coal and biomass in an existing coal fired power plant is being considered as a viable alternative to transition from non-renewable-to-renewable energy utilization. In this regard, various researches have been conducted in the last twenty years, in most of which the general conclusion is that the boiler efficiency decreases with respect to increasing biomass percentage in co-firing, nonetheless, additional study is deemed to be required, especially for waste biomass which are abundantly available in Indonesia. The waste biomass to be employed in this study are palm empty fruit bunch (EFB), rice husk, and wood pellet produced from sawdust. Co-firing combustion thermodynamic characteristics which are to be deployed in this study are air-to-fuel ratio (AFR), combustion CO2 emission, and adiabatic flame temperature. An open source CoolProp of thermodynamics properties formulations were implemented in order to evaluate thermodynamic properties of corresponding materials involved in this study. The results of the study show that AFR decreases with increasing biomass composition in the fuel, where the AFR rate of change per percent of biomassa are -0.018, -0.0406, and -0.026 for blend of coal-EFB, coal-rice husk, and coal-wood, respectively. As to the AFR characteristic, the emission of carbon dioxide is decreasing with increasing percent mass of biomass in the fuel composition. The CO2 rate of change with respect to percent biomass in fuel composition are -6.3x10-3, -1.12x10-2, and -6.48x10-3 for the blend of coal-EFB, coal-rice husk, and coal-wood, respectively. The adiabatic flame temperature is also decreasing with respect to increasing biomass mass percentage in fuel composition. The adiabatic flame temperature rate of change in K/%biomass are -13.93, -10.70, and -12.81 for the blend of coal-EFB, coal-rice husk, and coal-wood, respectively.
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Townsend, Simon A., Ian T. Webster, Michele A. Burford, and Julia Schult. "Effects of autotrophic biomass and composition on photosynthesis, respiration and light utilisation efficiency for a tropical savanna river." Marine and Freshwater Research 69, no. 8 (2018): 1279. http://dx.doi.org/10.1071/mf17172.
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The efficiency of light used for photosynthesis, when standardised for areal chlorophyll (Chl)-a biomass, is summarised by the light utilisation efficiency parameter and is dependent on light at the water’s surface, the underwater light climate and autotroph characteristics. Herein we examined the relationships between light, photosynthesis, respiration and autotroph biomass in a tropical savanna river in northern Australia during the dry season when autotroph biomass accumulated following wet season disturbance. The river’s autotrophs comprised mainly benthic microalgae, macroalgae and macrophytes. Total Chl-a and dry weight biomasses increased 4- and 27-fold respectively over 5 months, whereas photosynthesis doubled. Photosynthesis was light limited and, when standardised for Chl-a and dry weight biomasses, declined with increasing biomass, despite increasing incident light through the study period. We surmised this was due to self-shading and autotrophic composition, which had variable Chl-a content and resulted in a 10-fold reduction in the light utilisation efficiency with increasing light and biomass. Because respiration was tightly coupled to photosynthesis, biomass-standardised respiration also decreased with increasing biomass. Autotrophic self-shading and composition can have significant effects on light utilisation efficiency and the biomass–photosynthesis relationship, and warrant consideration when interpreting photosynthesis for river health monitoring.
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Borges, Amadeu D. S., Miguel Oliveira, Bruno M. M. Teixeira, and Frederico Branco. "Co-Valorisation Energy Potential of Wastewater Treatment Sludge and Agroforestry Waste." Environments 11, no. 1 (January 9, 2024): 14. http://dx.doi.org/10.3390/environments11010014.
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The growing demand for sustainable and environment-friendly energy sources resulted in extensive research in the field of renewable energy. Biomass, derived from organic materials such as agricultural waste, forestry products, and wastewater treatment plant (WWTP) sludge, holds great potential as a renewable energy resource that can reduce greenhouse gas emissions and offer sustainable solutions for energy production. This study focused on diverse biomass materials, including sludge from WWTPs, forest biomass, swine waste, cork powder, and biochar. Chemical and physicochemical characterizations were performed to understand their energy potential, highlighting their elemental composition, proximate analysis, and calorific values. Results showed that different biomasses have varying energy content, with biochar and cork powder emerging as high-energy materials with net heating values of 32.56 MJ/kg and 25.73 MJ/kg, respectively. WWTP sludge also demonstrated considerable potential with net heating values of around 14.87 MJ/kg to 17.44 MJ/kg. The relationships between biomass compositions and their heating values were explored, indicating the significance of low nitrogen and sulphur content and favourable carbon, hydrogen, and moisture balances for energy production. Additionally, this study looked into the possibility of mixing different biomasses to optimize their use and overcome limitations like high ash and moisture contents. Mixtures, such as “75% Santo Emilião WWTP Sludge + 25% Biochar,” showed impressive net heating values of approximately 21.032 MJ/kg and demonstrated reduced emissions during combustion. The study’s findings contribute to renewable energy research, offering insights into efficient and sustainable energy production processes and emphasizing the environmental benefits of biomass energy sources with low nitrogen and sulphur content.
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Umar, Datin Fatia, and Tati Rohayati. "Study on chemical characteristics of coal and biomass blend and the tendency of its ash deposition." Indonesian Mining Journal 24, no. 2 (October 2021): 113–26. http://dx.doi.org/10.30556/imj.vol24.no2.2021.1242.
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A coal and biomasses of empty fruit bunch (EFB), mesocarp fiber (MF) and palm kernel shell (PKS) were characterized in terms of its proximate, ultimate, calorific value and ash chemical composition. Ash fusion temperature (AFT) was carried out on coal and biomass blends with a composition in weight % of 95-5; 90-10 and 85-15. The coal used in this research has high calorific value of 6,106 cal/g. Results indicate that based on the AFT, the coal-biomass blends at some composition shows a medium tendency to ash deposition. While based on the chemical composition, generally the coal-biomass blends have a low tendency to slagging but have a high tendency to fouling. Coal-biomass blend at the coal composition of 85 wt% and PKS of 15 wt% (85-15) is recommended to be applied. The less the coal is used, the less the CO2 emission, so it is expected to reduce the GHG significantly.
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Lalonde, Sophie, and John A. Downing. "Phytofaun of Eleven Macrophyte Beds of Differing Trophic Status, Depth, and Composition." Canadian Journal of Fisheries and Aquatic Sciences 49, no. 5 (May 1, 1992): 992–1000. http://dx.doi.org/10.1139/f92-111.
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Macrophyte beds in 11 lakes of differing trophic conditions were sampled intensively to examine the influence of macrophyte abundance and composition, epiphyton biomass, phytoplankton concentration, and water depth on the abundance of phytophilous invertebrates. Numerical abundance and biomass of phytofaunal taxa were only weakly correlated. Phytofauna biomass ranged from 17 to 270 mg dry mass∙g macrophyte dry mass−1(1–29 g dry mass∙m−2) among the macrophyte beds. Multiple regression analysis showed that total phytofaunal biomass was positively correlated with the biomass of the three primary producers in the littoral zone: macrophytes, epiphyton, and phytoplankton. Phytofauna biomasses in deeper macrophyte beds or near the water surface were lower than those found in shallower water or near the sediment surface. Correlations of phytofauna biomass with macrophytes, epiphyton, and depth varied somewhat among phytofaunal taxa. The phytofauna biomass was often dominated by chironomid larvae, but gastropods, water mites, and oligochaetes were also important components of the phytofauna biomass. Small crustaceans such as cladocerans and copepods frequently were numerically dominant but usually composed only a small fraction of the biomass. Preference of various invertebrate taxonomic groups for particular species of aquatic macrophyte was slight.
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Herout, M., J. Malaťák, L. Kučera, and T. Dlabaja. "Biogas composition depending on the type of plant biomass used." Research in Agricultural Engineering 57, No. 4 (December 14, 2011): 137–43. http://dx.doi.org/10.17221/41/2010-rae.
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The aim of the work is to determine and analyse concentrations of individual biogas components according to the used raw materials based on plant biomass. The measurement is focused on biogas production depending on input raw materials like maize silage, grass haylage and rye grain. The total amount of plant biomass entering the fermenter during the measurement varies at around 40% w/w, the rest is liquid beef manure. The measured values are statistically evaluated and optimised for the subsequent effective operation of the biogas plant. A biogas plant operating on the principle of wet anaerobic fermentation process is used for the measurement. The biogas production takes place during the wet fermentation process in the mesophile operation at an average temperature of 40°C. The technology of the biogas plant is based on the principle of using two fermenters. It follows from the measured results that maize silage with liquid beef manure in the ratio of 40:60 can produce biogas with a high content of methane; this performance is not stable. At this concentration of input raw material, the formation of undesirable high concentrations of hydrogen sulphide occurs as well. It is shown from the results that the process of biogas production is stabilised by the addition of other components of plant biomass like grass haylage and rye grain and a limitation of the formation of hydrogen sulphide occurs. It follows from the results that the maize silage should form about 80% w/w from the total amount of the plant biomass used.
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Chételat, J., F. R. Pick, A. Morin, and P. B. Hamilton. "Periphyton biomass and community composition in rivers of different nutrient status." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 4 (April 1, 1999): 560–69. http://dx.doi.org/10.1139/f98-197.
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Epilithic periphyton was investigated in riffle zones of 13 rivers in southern Ontario and western Quebec to describe how algal biomass and community composition vary with nutrient concentration and water velocity during summer. Algal biomass (milligrams chlorophyll a (Chl a) per square metre) was strongly correlated with total phosphorus concentration (r2 = 0.56, p < 0.001) and conductivity (r2 = 0.71, p < 0.001) of the overlying water but unrelated to water velocity over the range of 10-107 cm·s-1. Differences in periphyton Chl a were associated with changes in biomass of Chlorophyta (r2 = 0.51, p = 0.001) and Bacillariophyta (r2 = 0.64, p < 0.001) and were not related to Rhodophyta and Cyanophyta biomass (p > 0.10). The relative proportions of taxonomic divisions varied with total standing stock. Percent Chlorophyta biomass increased with periphyton Chl a and was the largest fraction at moderately eutrophic sites. Rhodophyta contributed the most biomass at sites with the lowest Chl a. Cladophora, Melosira, and Audouinella biomasses were positively correlated with total phosphorus concentration over the range of 6-82 µg·L-1 (r2 = 0.39-0.64, p < 0.005), and these genera were dominant at sites with the highest nutrient concentrations.
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Kulikova, M. V., A. Yu Krylova, F. G. Zhagfarov, K. O. Krysanova, and A. L. Lapidus. "Plant Biomass as a Raw Material for Obtaining Products of Basic Organic Synthesis." Chemistry and Technology of Fuels and Oils 629, no. 1 (2022): 50–56. http://dx.doi.org/10.32935/0023-1169-2022-629-1-50-56.
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The review considers plant biomass as a potential renewable raw material for the production of CO2-neutral fuel, which does not affect the balance of carbon dioxide in the atmosphere. Evaluation of the characteristics of biomasses will make it possible to determine the potential for their integration into modern processes of petrochemistry and biochemistry. The work investigates the most common types of plant biomasses for the territory of the Russian Federation - wood waste and peat, as well as microalgae. The main characteristics of biomasses, their structural and elemental compositions are described. An assessment of the amount and energy value of some types of plant biomass has been carried out.
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Asadollahzadeh, Mohammadtaghi, Ali Ghasemian, Ahmadreza Saraeia, Hossein Resalati, and Mohammad J. Taherzadeh. "Production of fungal biomass protein by filamentous fungi cultivation on liquid waste streams from pulping process." BioResources 13, no. 3 (May 15, 2018): 5013–31. http://dx.doi.org/10.15376/biores.13.3.5013-5031.
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The aim of this study was to convert the spent liquors obtained from acidic sulfite and neutral sulfite semi-chemical (NSSC) pulping processes into protein-rich fungal biomass. Three filamentous fungi, Aspergillus oryzae, Mucor indicus, and Rhizopus oryzae, were cultivated on the diluted spent liquors in an airlift bioreactor with airflow of 0.85 vvm at 35 °C and pH 5.5. Maximum values of 10.17 g, 6.14 g, and 5.47 g of biomass per liter of spent liquor were achieved in the cultivation of A. oryzae, M. indicus, and R. oryzae on the spent sulfite liquor (SSL) diluted to 60%, respectively, while A. oryzae cultivation on the spent NSSC liquor (SNL) diluted to 50% resulted in the production of 3.27 g biomass per liter SNL. The fungal biomasses contained 407 g to 477 g of protein, 31 g to 114 g of fat, 56 g to 89 g of ash, and 297 g to 384 g of alkali-insoluble material (AIM) per kg of dry biomass. The amino acids, fatty acids, and mineral elements composition of the fungal biomasses corresponded to the composition of commercial protein sources especially soybean meal. Among the fungi examined, A. oryzae showed better performance to produce protein-rich fungal biomass during cultivation in the spent liquors.
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Amusa, Abiodun Abdulhameed, Abdul Latif Ahmad, and Jimoh Kayode Adewole. "Mechanism and Compatibility of Pretreated Lignocellulosic Biomass and Polymeric Mixed Matrix Membranes: A Review." Membranes 10, no. 12 (November 26, 2020): 370. http://dx.doi.org/10.3390/membranes10120370.
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In this paper, a review of the compatibility of polymeric membranes with lignocellulosic biomass is presented. The structure and composition of lignocellulosic biomass which could enhance membrane fabrications are considered. However, strong cell walls and interchain hindrances have limited the commercial-scale applications of raw lignocellulosic biomasses. These shortcomings can be surpassed to improve lignocellulosic biomass applications by using the proposed pretreatment methods, including physical and chemical methods, before incorporation into a single-polymer or copolymer matrix. It is imperative to understand the characteristics of lignocellulosic biomass and polymeric membranes, as well as to investigate membrane materials and how the separation performance of polymeric membranes containing lignocellulosic biomass can be influenced. Hence, lignocellulosic biomass and polymer modification and interfacial morphology improvement become necessary in producing mixed matrix membranes (MMMs). In general, the present study has shown that future membrane generations could attain high performance, e.g., CO2 separation using MMMs containing pretreated lignocellulosic biomasses with reachable hydroxyl group radicals.
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Serba, Elena, Liubov Rimareva, Marina Overchenko, Nadezhda Ignatova, Polina Tadzhibova, and Sergey Zorin. "Production of peptides and amino acids from microbial biomass in food and feed industries: biotechnological aspects." Foods and Raw Materials 8, no. 2 (September 30, 2020): 268–76. http://dx.doi.org/10.21603/2308-4057-2020-2-268-276.
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Introduction. Microbial biomass is a popular source of food ingredients and feed additives. Its high use has made it focus of many relevant studies. Yeast and fungal biomasses proved to be useful substrates that improve the quality and biological value of functional products. They differ in the content and composition of proteins and polysaccharides. The present research dealt with the enzymatic decomposition of proteins found in a novel fungal and yeast biomass. The research objective was to describe the peptide and amino acid composition of their enzymatic hydrolysates.
Study objects and methods. The research featured a new fungal and yeast biomass mix. Aspergillus oryzae is a mycelial fungus and a popular industrial producer of hydrolytic enzymes in food industry. As for the yeast, it was the Saccharomyces cerevisiae strain, which is often used in baking.
Results and discussion. The total content of identified amino acids in the fungal and yeast biomass was 306.0 mg/g, which was 1.5 times higher than in the fungal biomass alone. The biomass mix demonstrated a higher biological value of proteins than the yeast biomass. A set of experiments made it possible to compile a scheme for the biocatalytic destruction of polymers in the fungal and yeast biomass under the effect of fungal intracellular and endogenous enzymes. The article also contains a thorough description of the obtained enzymatic hydrolysates with various fractional compositions of peptides and free amino acids. Peptides with the molecular weight in the range of up to 29.0 kDa decreased by 2.1 times after 5 h of hydrolysis and by 10.7 times after 18 h. The designed conditions doubled the release of amino acids and increased the content of low-molecular-weight peptides up to 75.3%.
Conclusion. The research provided a new algorithm for the biocatalytic conversion of microbial biomass. Regulating the conditions of enzymatic hydrolysis made it possible to obtain enzymatic hydrolysates with a desired degree of protein degradation. They could serve as peptides and amino acids in functional food and feed products.
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Martinelli, Tommaso. "Plant morphology, vegetative biomass composition and energy content of three different Silybum marianum accessions." Acta Scientiarum Polonorum Hortorum Cultus 19, no. 6 (December 31, 2020): 71–78. http://dx.doi.org/10.24326/asphc.2020.6.6.
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Silybum marianum (L.) Gaertn. (milk thistle) is plant species that has been utilized principally for medicinal purposes for more than 2000 years. Recently it was proposed for biomass production in marginal environments, but vegetative biomass compositional analyses had not been available so far. The study of plant morphology and biomass composition was conducted on three different S. marianum accessions grown under open field conditions. The results indicate that plant morphological traits show major differences between accessions: this suggests that the available natural variability can be further utilized in order to develop improved S. marianum cultivars. Biomass compositional analysis shows that extractives, ash, lignin and cellulose content are comparable to other herbaceous bioenergy crops and that these traits display only limited variability in the studied accessions. Hemicellulose fraction is composed only by xylans and its content appears averagely lower in comparison to other herbaceous biomasses. Interestingly, in S. marianum biomass total nitrogen content is lower if compared to other herbaceous species. The possible involvement of this specific biomass trait in S. marianum nitrogen utilization efficiency has to be further investigated.
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Tomlin, A. D., and J. J. Miller. "Composition of the soil fauna in forested and grassy plots at Delhi, Ontario." Canadian Journal of Zoology 65, no. 12 (December 1, 1987): 3048–55. http://dx.doi.org/10.1139/z87-462.
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There were several differences between invertebrate fauna collected from 15 cm deep cores taken from previously cultivated soil (now in grass) and fauna of a similar Fox loamy sand series in a nearby woodlot at Delhi, Ontario (42°51′ N, 80°30′W). Soil invertebrate populations in the grassy field were less dense (931 × 103 vs. 1853 × 103 animals/m2) and less diverse, had less than half of the biomass (1.2 vs. 2.9 g dry wt./m2), and exhibited little significant decrease in invertebrate densities with increasing soil depth compared with woodlot soil cores; woodlot soils exhibited significant decreases in invertebrate densities with increasing soil depth. The litter layer (LFH) of the woodlot provided the highest invertebrate densities and biomasses of any soil horizon tested over the 5-month sampling period. Percent abundances at both sites for most taxa were relatively similar; nematodes, protozoans, and mites were most abundant and earthworms, least abundant. The category "other arthropods" (including hexapods, myriapods, and araneids) was the largest contributor at both sites when taxa were ranked according to biomass. Earthworms were virtually nonexistent in the grassy field and were represented by only two species, Dendrobaena octaedra (Savigny) (which was dominant in both abundance and biomass) and Aporrectodea tuberculata (Eisen), in woodlot soil. Woodlot faunal densities and biomasses for most taxa were similar to comparable Eurasian sites of similar climate and vegetation.
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Vollenweider, Richard A. "Elemental and biochemical composition of plankton biomass; some comments and explorations." Archiv für Hydrobiologie 105, no. 1 (March 23, 1989): 11–29. http://dx.doi.org/10.1127/archiv-hydrobiol/105/1989/11.
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Thep-On, Laddawan, Shahariar Chowdhury, Kua-Anan Taechato, Anil Kumar, and Issara Chanakaewsomboon. "Optimization of Biomass Fuel Composition for Rubber Glove Manufacturing in Thailand." Sustainability 14, no. 19 (September 30, 2022): 12493. http://dx.doi.org/10.3390/su141912493.
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The demand for rubber gloves has significantly increased in both medical and non-medical fields due to the spread of the coronavirus in 2019. It is challenging for rubber glove manufacturing industries to balance the production and demand for the product. Additionally, they must determine techniques to decrease the production costs so as to make rubber gloves more economical for consumers. Generally, natural gas, fossil fuels, and renewable energy sources are used worldwide in the manufacturing of rubber gloves. In addition, Thailand uses biomass energy for rubber glove production, but biomass utilization is not economically friendly. This study used different biomasses as fuel in rubber glove production so as to reduce production costs and make the process more environmentally friendly. Wood chip (WC), palm kernel shells (PKS), and oil palm mesocarp fiber (OPMF) biomass were collected from local regions and used in different ratios. The samples of WC, PKS, and OPMF were prepared in four different ratios, namely, 88:12:0, 85:15:0, 85:13:2, and 85:10:5, for efficient biomass utilization. The 85:10:5 (WC: PKS: OPMF) ratio was found to be the optimal ratio as the annual production costs of rubber gloves significantly decreased to USD 1.64 per 1000 units of gloves. Furthermore, this biomass ratio also showed the best boiler efficiency of 74.87%. Therefore, WC, PKS, and OPMF biomass are recommended as fuel for rubber glove industries to make sustainable and economical production processes.
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Javed, Muhammad Amir, Naveed Ramzan, Umair Aslan, Hina Mukhtar, Iftikhar Hussain, and Abdul Zahir. "IMPACT OF HYDROFLUORIC (HF) ACID TREATMENT ON MORPHOLOGICAL AND CHEMICAL STRUCTURE OF AGRICULTURAL WASTES." International Journal of Biomass and Renewables 12, no. 1 (April 28, 2023): 13. http://dx.doi.org/10.61762/ijbrvol12iss1art22207.
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Acid, base and/or water treatments expand biomass utilisation by reducing ash contents and improving energy density and higher heating values. Dilute acid treatment results in negative impacts on the physiochemical structure of biomass. This study aimed to analyse the effects of hydrofluoric (HF) acid (5% w/w) on the morphological and chemical structure of Wheat Straw (WS), Cotton Stalk (CS) and Rice Husk (RH). Scanning Electron Microscopy (SEM) exposed physical changes after treatment, and Fourier Transform Infrared (FTIR) spectroscopy was used to evaluate the changes in available functional groups in the composition of biomass samples. Dilute HF resulted in pronounced changes in morphology and chemical functional groups of all biomasses. Proximate analysis showed carbonaceous material is also affected; the increment in volatiles (9.27%, 7.7% and 6.9% for RH, WS and CS, respectively) and fixed carbon was observed while ash contents reduced. Furthermore, the influence of all samples on the thermal processing of biomass is compared.
Keywords: biomasses, acidic pretreatment, ash contents, morphology, aromaticity
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Machado, Henrique, Ana F. Cristino, Sofia Orišková, and Rui Galhano dos Santos. "Bio-Oil: The Next-Generation Source of Chemicals." Reactions 3, no. 1 (January 28, 2022): 118–37. http://dx.doi.org/10.3390/reactions3010009.
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Bio-oil, although rich in chemical species, is primarily used as fuel oil, due to its greater calorific power when compared to the biomass from which it is made. The incomplete understanding of how to explore its chemical potential as a source of value-added chemicals and, therefore, a supply of intermediary chemical species is due to the diverse composition of bio-oil. Being biomass-based, making it subject to composition changes, bio-oil is obtained via different processes, the two most common being fast pyrolysis and hydrothermal liquefaction. Different methods result in different bio-oil compositions even from the same original biomass. Understanding which biomass source and process results in a particular chemical makeup is of interest to those concerned with the refinement or direct application in chemical reactions of bio-oil. This paper presents a summary of published bio-oil production methods, origin biomass, and the resulting composition.
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Moretti, Linda, Fausto Arpino, Gino Cortellessa, Simona Di Fraia, Maria Di Palma, and Laura Vanoli. "Reliability of Equilibrium Gasification Models for Selected Biomass Types and Compositions: An Overview." Energies 15, no. 1 (December 22, 2021): 61. http://dx.doi.org/10.3390/en15010061.
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In this paper, the authors present an overview of biomass gasification modeling approaches with the aim of evaluating their effectiveness as a modeling tool for the design and optimization of polygeneration plants based on biomass gasification. In fact, the necessity to build plant operating maps for efficiency optimization requires a significant number of simulations, and non-stoichiometry equilibrium models may allow fast computations thanks to their relative simplicity. The main objective consists of the assessment of thermodynamic equilibrium models performance as a function of biomass type and composition to better understand in which conditions of practical interest such models can be applied with acceptable reliability. To this aim, the authors developed two equilibrium models using both a commercial software (referred as Aspen model) and a simulation tool implemented in a non-commercial script (referred as analytical model). To assess their advantages and disadvantages, the two models were applied to the gasification simulation of different biomasses, employing experimental data available from the scientific literature. The obtained results highlighted strengths and limitations of using equilibrium models as a function of biomass type and composition. For example, they showed that the analytical model predicted syngas composition with better accuracy for biomass types characterized by a low ash content, whereas the Aspen model appeared to fairly predict the syngas composition at different conditions of ER; however, its accuracy might be reduced if the properties of the treated biomass changed.
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Delesalle, B. "Le phytoplancton de l'atoll de Takapoto (archipel des Tuamotu, Polynésie française) : variabilité spatiale et temporelle de la biomasse, la production primaire et la composition sur une période de 24 ans." Aquatic Living Resources 14, no. 3 (June 2001): 175–82. http://dx.doi.org/10.1016/s0990-7440(00)01098-6.
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Xu, Yun, and Wolfgang Schrader. "Studying the Complexity of Biomass Derived Biofuels." Energies 14, no. 8 (April 7, 2021): 2032. http://dx.doi.org/10.3390/en14082032.
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Biofuel produced from biomass pyrolysis is a good example of a highly complex mixture. Detailed understanding of its composition is a prerequisite for optimizing transformation processes and further upgrading conditions. The major challenge in understanding the composition of biofuel derived from biomass is the wide range of compounds with high diversity in polarity and abundance that can be present. In this work, a comprehensive analysis using mass spectrometry is reported. Different operation conditions are studied by utilizing multiple ionization methods (positive mode atmospheric pressure photo ionization (APPI), atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI) and negative mode ESI) and applying different resolving power set-ups (120 k, 240 k, 480 k and 960 k) and scan techniques (full scan and spectral stitching method) to study the complexity of a pyrolysis biofuel. Using a mass resolution of 960 k and the spectral stitching scan technique gives a total of 21,703 assigned compositions for one ionization technique alone. The number of total compositions is significantly expanded by the combination of different ionization methods.
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Yaiche Achour, Hafsa, Cristina Blanco Llamero, Sid Ahmed Saadi, Abdelghani Zitouni, and Fransisco Javier Señoráns. "Ultrasound assisted extraction of carotenoids from green and orange biomasses of Dunaliella Salina DunaDZ1." Annals of the University Dunarea de Jos of Galati. Fascicle VI - Food Technology 46, no. 2 (September 1, 2022): 22–34. http://dx.doi.org/10.35219/foodtechnology.2022.2.02.
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Microalgae are described as a potential alternative source of bioactive compounds that are environmentally friendly. Dunaliella on its own is well known due to its potential to accumulate large amounts of carotenoids, especially β-carotene. Green and orange biomasses from a new Dunaliella salina strain DunaDZ1 isolated from an Algerian Salt Lake were evaluated for carotenoids composition and antioxidant activity. Ultrasound-Assisted Extraction (UAE) was employed using different extracting solvents. Furthermore, UAE extracts were then analyzed for their chemical composition by TLC, HPLC-DAD and for the antioxidant activity. Lutein was the main carotenoid in the green biomass, with the highest amount for ethyl acetate extract (393.19 mg/g). However, for the orange biomass, the main carotenoid was trans, β-carotene (131.83 mg/g) in the acetonic extract. Moreover, several others carotenoids were detected, belonging to xanthophylls and carotenes. Additionally, ultrasonic-assisted extraction with ethyl acetate produced the extract with the highest antioxidant activity for both D. salina biomasses. These extracts could be used as a natural antioxidant and as an ingredient for functional foods formulation.
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Peni, Dumitru, Marcin Dębowski, and Mariusz Jerzy Stolarski. "Influence of the Fertilization Method on the Silphium perfoliatum Biomass Composition and Methane Fermentation Efficiency." Energies 15, no. 3 (January 27, 2022): 927. http://dx.doi.org/10.3390/en15030927.
Full textAbstract:
Biogas production is one of the solutions for replacing fossil fuels, which promotes the widespread use of green energy. The aim of this study was to determine the potential of Silphium perfoliatum as an energy crop for biogas production, as well as the effect of different fertilization doses (0, 85 and 170 kg N ha−1) on the production potential (NL CH4 kg−1 VS) of Silphium perfoliatum. The study investigated the use of different feedstocks, such as raw and ensiled Silphium perfoliatum biomass. The methane production ranged between 193.59 and 243.61 NL CH4 kg−1 VS. The highest biogas production potential was achieved with the biomasses which were cultivated with the highest fertilization dose (170 kg N ha−1), both for raw and ensiled crop biomasses, although the difference from the other fertilization doses was not significant. The feedstock (biomass and silage) and digestate parameters were investigated as well. The use of Silphium perfoliatum for biogas production seems very promising since its methane production potential was found to be similar to that of the most common energy crop, such as maize, indicating that Silphium perfoliatum can compete in the future with maize.
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Alvarez-Barreto, Jose F., Fernando Larrea, Maria C. Pinos C, Jose Benalcázar, Daniela Oña, Daniela A. Viteri, Marco Leon, and Daniela Almeida-Streitwieser D. "Chemical Pretreatments on Residual Cocoa Pod Shell Biomass for Bioethanol Production." Bionatura 6, no. 1 (February 15, 2021): 1490–500. http://dx.doi.org/10.21931/rb/2020.06.01.9.
Full textAbstract:
Cocoa pod shell is an essential agricultural residue in Ecuador, and this study addressed its potential valorization for bioethanol production. For this, three types of pretreatments, acid, alkaline, and autohydrolysis, were applied to pod shells from two different cocoa types, national and CCN-51. to remove the lignin. Untreated and treated biomasses were characterized by composition, thermal stability, Fourier transformed infrared spectroscopy (FITR), and scanning electron microscopy (SEM). The treated biomass was then enzymatically hydrolyzed with cellulase. Reducing sugars were quantified after pretreatments and enzymatic hydrolysis, and the pretreatment liquors and the enzymatic hydrolysates were subjected to alcoholic fermentation with Saccharomyces cerevisiae. There were substantial differences in composition between both biomasses, particularly in lignin content, with national cocoa having the lowest values. All pretreatment conditions had significant effects on biomass composition, structure, and thermal properties. After alkaline pretreatment, the biomass presented the highest cellulose and lowest lignin contents, resulting in the highest reducing sugar concentration in the pretreatment liquor. The highest lignin content was found after the acid pretreatment, which resulted in low, reducing sugar concentrations. Autohydrolysis produced similar results as the acid pretreatment; however, it resulted in the highest sugar concentration after enzymatic hydrolysis, while the acid-treated sample had negligible levels. After fermentation, there were no differences in productivity among the pretreatment liquors, but autohydrolysis had the largest ethanol yield. In the hydrolysates, it was also autohydrolysis that resulted in higher productivity and yield. Thus, there is an indication of the formation of inhibitors, both enzymatic activity and ethanol production, in the acid and alkaline pretreatments, and this should be tackled in future research. Nonetheless, given the crucial changes observed in biomass, we believe that cocoa pod shell pretreatment has potential for the generation of reducing sugars that could be further used in different bioprocesses, nor only bioethanol production.
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Origenes, M. G., and R. L. Lapitan. "Carbon stock assessment through above-ground biomass of trees at different forest composition in Mt. Malindawag, Lubilan, Naawan, Misamis Oriental, Philippines." International Journal of Forestry, Ecology and Environment 11, no. 01 (January 15, 2021): 100–113. http://dx.doi.org/10.18801/ijfee.030121.11.
Full textAbstract:
It is documented that the amounts of carbon stored and its level of degradation in different forests compositions and different types of forest is mostly unknown, Philippines is no exemption as little was done in some places of this country. This study was conducted to assess carbon stock through above ground biomass of trees at different forest composition in Mt. Malindawag. There were three (3) 20m x 20m sample plots (quadrats) (400m2 equivalent to 0.04 ha) established as replicate plots provided with 50m intervals. Forest composition such as the Agroforestry area, mixed forest area and the Plantation forest were assessed in terms of the number of individuals, number of species, diameter, and height to calculate the biomass, tree biomass density as well as the carbon stock. Based on the results of the study conducted in different forest compositions of Mt. Malindawag, plantation forest has the highest carbon stocking rate. However, these results were not significantly different from the other forest composition. This was associated with a higher accumulated diameter, which resulted in higher biomass and eventually carbon stock. Species found in this forest composition are productive and have lesser number of individuals; therefore, there is lesser competition for resources such as light. Such a mechanism might contribute to the higher biomass and carbon stock. However, the result may not be right to other areas due to uncontrollable factors, anthropogenic and environmental factors. Hence, it is recommended to have further studies on areas where trees have similar age, species diversity index as well as stand development and site productivity for a more accurate and quantifiable carbon stock.
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Štolcová, J. "Secondary succession on an early abandoned field: vegetation composition and production of biomass." Plant Protection Science 38, No. 4 (February 6, 2012): 149–54. http://dx.doi.org/10.17221/4871-pps.
Full textAbstract:
During 1996–2000 the secondary succession on a field left fallow was investigated. The experimental area was divided into a ploughed and an unploughed part. Both parts were divided into 5 × 5 m plots that were either left intact (control), mowed in June or July, or superficially cultivated in June. The position of the plots was identical each year. In successive years total dry matter production decreased in all experimental plots; in unploughed plots more than in ploughed ones. The spread of Cirsium arvense (L.) Scop. was increased by ploughing and superficial cultivation. Ploughing stimulated the spread of perennial dicotyledonous plants more than mowing in June and July. Superficial cultivation increased the spread of perennial dicotyledonous plants in the first years. Later on the proportion of perennial dicotyledonous plants decreased and after 5 years the plots were dominated by Anisantha sterilis (L.) Nevski. The incidence of Elytrigia repens (L.) Desv. was highest in the 5th year on unploughed control plots. The spread of perennial monocotyledonous plants was lowest in ploughed and superficially cultivated plots.