6 research outputs found
ÉTUDE ET CARACTÉRISATION DU CHARBON ÉCOLOGIQUE PRODUIT À PARTIR DES DÉCHETS AGRICOLES EN VUE DE SON UTILISATION DANS LES MÉNAGES AU CAMEROUN
No full textThis work focuses on the characterization of eco-friendly charcoal and highlights anenergy and economic analysis of the production and household use of eco-friendly charcoalin Cameroon. The aim of the study is to analyse the feasibility of adapting eco-friendlycharcoal produced from coconut shells, rattan waste, bagasse and banana peels as cookingfuel. The objectives are to assess the energy potential of agricultural biomass, determinethe physico-chemical characteristics of the charcoal produced, and analyse the energyand economic feasibility of the production and household cooking use of the charcoal. Atheoretical assessment of the energy potential of agricultural biomass is performed usingthe Residue/Product Ratio method. Water boiling tests and experimental protocols documented by the American Society for Testing and Materials (ASTM) and the EuropeanCommittee for Standardization (CEN) allow the characterization of charcoal. Data collection in an eco-friendly briquetting company leads to the energy analysis of the productionprocess. Simulation of the Net Present Value, profitability index, and life cycle cost modelsallows one to investigate the economic viability of charcoal production as well as its useas cooking fuel in a typical household in Cameroon. The results show that Cameroon hasa significant potential for agricultural biomass for briquette production. With an annualproduction of 46,236,156 tonnes, agricultural residues can produce 7,706,260 tonnes ofbriquettes each year for an energy potential of 106,139 TJ. This agricultural potential isunder-exploited because of inadequate technology, the choice of raw materials, and thelack of financial support from the public authorities, among others. The characterizationof charcoal produced from coconut husks, rattan waste, sugarcane bagasse, and bananapeels reveals that they have interesting combustion properties. The net calorific valuevaries between 16.98 and 32.16 MJ/kg, the moisture content is less than 8.00%, and thefixed carbon content ranges between 15.15 and 19.49%. An analysis of the productionshows that the process is energy efficient, with primary energy consumption ranging from0.09 to 0.56 kWh for one kilowatt-hour of energy produced. Economic calculations revealthat only the conversion of coconut husks and rattan waste is an economically viableprocess. The substitution of Liquefied Petroleum Gas, firewood or wood charcoal can beeconomically beneficial for households. Households can save up to 52% on their cookingfuel expenses. Eco-friendly charcoal could therefore be considered a suitable fuel for households in Cameroon. Eco-friendly charcoal can therefore be considered a suitable fuel forhouseholds in Cameroon, but other such considerations as the study of logistics or theviews of households need to be investigated to validate this.Ce travail porte sur la caractérisation du charbon écologique et met en exergue uneétude énergétique et économique de la production dudit charbon ainsi que son utilisation dans les ménages au Cameroun. Le but de l’étude est d’analyser la faisabilité del’adaptation du charbon écologique produit à partir de coques de noix de coco, déchets derotin, bagasse de et pelures de banane comme combustible de cuisson. Les objectifs sontd’évaluer le potentiel énergétique de la biomasse agricole, déterminer les caractéristiquesphysico-chimiques du charbon écologique produit, et faire une analyse énergétique et dela faisabilité économique de la production et de l’utilisation domestique dudit charbon.Une évaluation théorique du potentiel énergétique de la biomasse agricole a été faite parla méthode du Rapport Résidu/Produit ; les test d’ébulition de l’eau et les protocolesexpérimentaux documentés dans les normes American Society for Testing and Materials(ASTM) et Comité Européen de Normalisation (CEN) ont permis d’aboutir à la caractérisation du charbon. La collecte de données dans une industrie de conversion de la biomasseagricole en charbon écologique a conduit à l’analyse énergétique du processus de production de charbon. La simulation des modèles de calculs de Valeur Actuelle Nette, Indicede Profitabilité et côuts de cycle de vie a permis d’évaluer la viabilité économique de laproduction des briquettes ainsi que leur utilisation comme combustible de cuisson dansun ménage. Les résultats montrent que le Cameroun dispose d’un potentiel importantde biomasse agricole pour la production de briquettes. Avec une production annuelle de46 236 156 tonnes, les résidus agricoles peuvent produire 7 706 260 tonnes de briquetteschaque année pour un potentiel énergétique de 106 139 TJ. Ce potentiel agricole estsous-exploité à cause de la technologie inadéquate, du choix des matières premières et lemanque d’accompagnement financier par les pouvoirs publics entre autres. La caractérisation du charbon produit à partir des coques de noix de coco, déchets de rotin, bagassede canne à sucre et pelures de banane révèle qu’elles ont des propriétés de combustionintéressantes. Le pouvoir calorifique inférieur varie de 16,98 à 32,16 MJ/kg, le taux d’humidité est inférieur à 8,00 % et le taux de carbone fixe est compris entre 15,15 et 19,49%. L’analyse du système de production de charbon écologique montre que ce processusest énergétiquement viable, l’énergie primaire consommée va de 0,09 à 0,56 kWh pour unkilo Wattheure d’énergie produite. Les calculs économiques révèlent que seule la conversion des coques de noix de coco et déchets de rotin est un processus économiquementrentable. La substitution du charbon écologique au Gaz de Pétrole Liquéfié, au bois dechauffe ou au charbon de bois peut être économiquement bénéfique pour les ménages.Ces derniers peuvent faire des économies allant jusqu’à 52,00 % de leurs dépenses liéesaux combustibles de cuisson. Le charbon écologique peut donc être considéré comme uncombustible adapté pour les ménages au Cameroun, mais d’autres aspects comme l’étudede la logistique ou le point de vue des ménages doivent être investigués pour le confirme
Water Source Management in the Peri-Urban Area in Subsaharan Africa: Environmental and Health Impacts Assessment in Yaounde-Cameroon
No full textThis study was carried out in the outskirts of the Yaoundé VII district had the main objective of assessing the social and environmental impacts of water management in the outskirts of Yaoundé VII.
This work was carried out from December 2021 to March 2022, followed by an appropriate methodology to meet the outlined objectives:(1) in-situ evaluation of physicochemical parameters of well water; (2) laboratory studies of groundwater samples for bacteria and heavy metals; and (3) questionnaire surveys to acquire water consumption demographics were all part of our study. It consisted of under taking site visits, take pictures, and make household surveys and direct observations, analysis at several water points.
The results show that the villages in the surrounding area of the district of Yaoundé VII obtain water through alternative resources such as wells at 60 %, sources 30 %, drillings, 7 %, rivers and others at 3 %, due to lack of Camwater network. Analysis at the water points has revealed that the physico-chemical parameters such as COD, BOD5, TSS, NO3, PO3, have average percentages respectively 83 mg/L, 35 mg/L, 14 mg/L, 0,33 mg/l and the biological parameters such as faecal coliforms faecal streptococci and total coliforms have percentages of 329,25 (UFC/100 ml), 115,5(UFC/100 ml), 835 (UFC/100 ml), These parameters in their majority do not meet with the MINEPDED environmental standards. This can be explained due to anthropogenic activities (fields, brick, factories, etc), that impact on the quality of water from different points of water villages covered. However, 10 positive and 02 negative impacts were identified. Alternative water resources in the villages do not meet certain environmental standards and human anthropogenic activities are a source of negative impacts such as poor well maintenance, which can cause many water borne diseases like typhoid fever.
More supply in water like boreholes should be built, or establish the Camwater network for better water management by the populations of the peripheral zone of the district of Yaoundé VII
Economic Viability Investigation of Mixed-Biomass Briquettes Made from Agricultural Residues for Household Cooking Use
No full textThis paper presents a theoretical evaluation of the prices of mixed briquettes produced from coconut shells (CCS), banana peels (BNP), rattan waste (RWT), and sugarcane bagasse (SGC) and, on the other hand, an analysis of the economic viability of their use as a replacement for conventional household fuels (liquefied petroleum gas, fuelwood, and wood charcoal) in households in Cameroon. The investigation was carried out using the life cycle cost method on a typical household over a ten-year period with annual cooking energy requirements of 950 kWhth. The SGC–CCS and SGC–RWT mixed briquettes with ratios higher than 7.75% and 11.1%, respectively, have prices lower than EUR 0.063/kWhth. The Present Value of the Net Benefit is positive for the use of SGC–CCS and SGC–RWT mixed briquettes. The results show that by making the right mixes of residues, it is possible to obtain biomass briquettes that are less expensive than conventional fuels
Energy Performance Evaluation of a Solar PVT Thermal Energy Storage System Based on Small Size Borefield
No full textIn this study, a PVT-based solar-assisted ground source heat pump (SAGSHP) system with a small size borefield as the long-term heat storage component was energetically evaluated. The mathematical model of the system was formulated in TRNSYS and three cities with distinctive climates were chosen: Athens (Greece); Melbourne (Australia); and Ottawa (Canada). The parametric analyses were carried out for 10 years by varying the number of the PVT collectors and the size of the earth energy bank (EEB). The evaluation of the systems was made via two energy indicators, and the heat flow across the EEB was analyzed. The under-consideration system was found capable of establishing self-sufficiency as regards the energy consumption (renewable power fraction RPF > 1) for all locations. Namely, for Athens, any system with more than four PVT collectors, and for Melbourne, any system with more than eight PVTs was found with an RPF higher than 1, regardless of the EEB size. For Ottawa, self-sufficiency can be achieved with PVT arrays larger than 12 collectors for small EEBs, and with eight collectors for larger EEBs. The storage capacity was found to be an important parameter for the energy performance of the system. In particular, it was determined that, as the storage capacity enlarges the RPF and the seasonal performance factor (SPF) of the system improves, mainly due to the reduction of the electricity consumed by the heat pump and the auxiliary heating. Moreover, a larger storage capacity facilitates solar heat production by enlarging the available heat storage volume and by maintaining the EEB at relatively low temperatures
First Law Comparison of a Forced-Circulation Solar Water Heating System with an Identical Thermosyphon
No full textThe main categories of solar water heating systems (SWHSs) are the thermosyphon and the forced circulation (FC). This paper presents an experiment carried out with the aim to compare the energy performance of the FC with a thermosyphon SHWS. Identical SWHSs were installed side by side at the University of West Attica in Athens, Greece. Domestic hot water load was applied to both systems via a microcontroller-based dispensing unit which mimics the demand profile. The trial period comprised the last two months of spring (April and May). For the first law assessment, two energy indicators were utilized: the solar fraction (SF) and the thermal efficiency of the system (ηth). On days with distinctive weather conditions, both systems obtained approximately equal SF and ηth values, without a specific preference between the ambient conditions and the type of SWHS. Regarding a four-day nonstop operation, the FC overperformed the thermosyphon system at both energy indicators. Namely, for the FC and the thermosyphon SWHS, the SF was calculated to be 0.62 and 0.48, and the ηth was 68.2% and 53.3%, respectively
Techno-economic analysis of viability of two stand-alone water pumping systems for rural areas of Kanem oasis: Case studies of solar photovoltaic (PV) and solar organic Rankine cycle (ORC) systems
No full textThis study addresses the challenge of providing affordable water through stand-alone systems. The aim is to identify the most cost-effective system in terms of energy and economics. An innovative, multi-criteria approach combining financial and energy analysis is used to achieve this objective. It was found at the first time, that the average stable operating irradiation for both systems was 6500 Wh/m2, with a saving energy ratio of 0.0063 for PV and 0.062 for ORC, corresponding to a maximum pumping flow rate of 30 m3/h for a geometric head ranging from 50m to 80m. The total surface area covered by the solar field is 206.1 m2 for PV compared to 200 m2 for the ORC system operating with R134a. Economic analysis revealed that PV has a LCOE of 0.308 USD/kWh for the ORC, corresponding to NPV of 6573.1 USD, respectively, for all organic fluids chosen in the ORC system. Furthermore, under the same operational conditions, PV has a Payback Period (PBP) of 2.3 years compared to 3.5 years for the ORC. Water pumping by autonomous systems saves 0.08 USD/kWh for the PV. The carbon saving is 15632 kgCO2 for ORC system and 16000 kgCO2 for PV system, the corresponding carbon cost is respectively 10942 USD. The multi-criteria sensitivity analysis showed that the ORC system is more profitable than the PV system at higher geometric heights. Even during low sunshine periods, the ORC maintains stable power production. These results demonstrate that the ORC is versatile and suitable for applications like water pumping, offering a strong alternative to mature and efficient PV systems. This finding contribute advances knowledge on ORC sustainability and applications
