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Search Results: 1 - 10 of 20816 matches for " Jean Koulidiati "
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α-Endosulfan Removal from Water by Adsorption over Natural Clays from Burkina Faso: An Isothermal Study  [PDF]
Arsène H. Yonli, Hermann A. Kabore, Jean Koulidiati
Journal of Materials Science and Chemical Engineering (MSCE) , 2014, DOI: 10.4236/msce.2014.211007
Abstract: The present study carried out the α-endosulfan removal from water by adsorption over natural clays from the western region of Burkina Faso. The adsorption experiments were performed over raw clay samples at room temperature in batch reactor and the obtained adsorption isotherms were well fitted by Fowler-Guggenheim model. It was pointed out for all samples that α-endosulfan was physisorbed in the interlayer space of the clay samples. The maximal adsorption capacities were respectively about 9.12, 6.98 and 4.13 mg/g for KO2, KO1 and KW1 samples. The differences in terms of adsorption capacity for the three samples were due to the presence of illite in the samples KO2 and KO1 when the KW1 sample contained essentially kaolinite in its structure. When the interlayer space was large enough as for samples with illite a greater amount of α-endosulfan molecules were adsorbed. It was also shown that the samples with the higher surface area were the most efficient for the removal of α-endosulfan molecules from water. Moreover, this study exhibited that the α-endosulfan adsorption depended on the crystallites size; the samples presenting largest crystallites had the greatest adsorption capacities.
A Convective Thin Layer Drying Model with Shrinkage for Kent Mango Slices  [PDF]
Alfa Oumar Dissa, Hélène Desmorieux, Jean Koulidiati
Advances in Chemical Engineering and Science (ACES) , 2016, DOI: 10.4236/aces.2016.61002
Abstract: In this work, a model of convective drying of mango slices was developed and validated by experiments. This model was established by considering slices shrinkage in the energy and the mass balances during the thin layer drying. The drying kinetics and the temperature curves of the product were simulated using the model at various drying temperatures. The simulated curves were then compared to the experimental curves obtained using a convective dryer controlled in temperature and moisture. The results showed that the drying curves were suitably fitted by the thin layer drying model with a correlation coefficient r2 = 0.997. Thus, taking shrinkage into account, it is possible to predict more effectively the thin layer drying kinetics of mango slices. This study therefore contributed to the mango drying modelling and to the mango dryer setting.
Characterization and Potential Recovery of Household Solid Waste in the City of Ouagadougou (Burkina Faso)  [PDF]
Kayaba Haro, Issoufou Ouarma, Bernard Nana, Antoine Bere, Jean Koulidiati
Journal of Environmental Protection (JEP) , 2018, DOI: 10.4236/jep.2018.94021
Abstract: This study on physical and physicochemical characteristics of household solid waste (HSW) in the city of Ouagadougou by using MODECOM, “Method of Characterization of Household waste” was done fifteen (15) years after the first study. Special attention has been paid to waste sampled and also to estimate energy content, namely the higher heating value (HHV) and the lower heating value (LHV). As a general tendency, the results showed a sensitive evolution in the physical parameters of waste (composition by size and composition by category) and also in the physicochemical parameters (moisture content and energy content). The results of HSW composition study showed that regardless the seasons, fermentable fraction is dominant (39% in the rainy season and 20% in the dry season) followed by plastics (18% in the rainy season and 20% in the dry season). The moisture content is measured to be 56.69% and 37.69% respectively in the rainy season and dry season. The results analysis of the potential of recovery showed that the organic recovery is more important (60% in the rainy season and 55% in the dry season) than the matter recovery (43% in the rainy season and 46% in the dry season). These results highlight the need for organic recovery and matter recovery of HSW in the city of Ouagadougou. The results from the analysis of the energy content showed that the HHV is estimated to be 17.94 MJ/kg in the rainy season and 17.96 MJ/kg in the dry season. The LHV is calculated to be 6.38 MJ/kg in the rainy season and 10.27 MJ/kg in the dry season. These results suggest that incineration as treatment of HSW in the city of Ouagadougou is not economically an appropriate option.
Environmental Impacts of Waste Management Deficiencies and Health Issues: A Case Study in the City of Kaya, Burkina Faso  [PDF]
Patricia Kafando, Bila Gérard Segda, Jean Fidèle Nzihou, Jean Koulidiati
Journal of Environmental Protection (JEP) , 2013, DOI: 10.4236/jep.2013.410124
Abstract:

In this study, a stratified survey sampling was used in order to broaden our knowledge on the management systems of household waste in the town of Kaya/Burkina Faso. Population study consists of households of the town of Kaya. The sample size was fist determined using the sample size calculation formula. Then four (04) strata comprising the town of Kaya sectors that have a Health and Social Promotion Center (HSPC) have been considered. A random household selection method, used inside each stratum and a number of 468 households representative of the town’s population, was surveyed. We have addressed all solid and liquid waste management strategies in those four strata. For each stratum, waste disposal infrastructure, its management in the households and its impacts on the town’s environment and populations’ health were screened. Data collected are presented through descriptive statistics in mean of tables and graphs. Frequently reported diseases in the four HSPCs have been correlated with waste management and disposal methods in the town. Poor handling, evacuation and disposal of waste have numerous negatives impacts on the city’s environment such as proliferation of mosquitoes and flies, bad odors, visual pollution. These negatives impacts on the environment in turn have negatives impacts on the health of the city residents. Malaria appears the most encountered disease followed by Acute Respiratory Infection and Diarrhea. Suggestions aimed at improving waste management and the reduction of its deficiencies impacts on the health of the population has been made.

Thermal Degradation of Polyethylene Bags and Millet Stalks: Influence of the Temperature and the Local Concentration of Oxygen on the Conversion Rate of Carbon  [PDF]
Salifou K. Ouiminga, Thomas Rogaume, Tizane Daho, Franck Richard, Jean Koulidiati
Advances in Chemical Engineering and Science (ACES) , 2012, DOI: 10.4236/aces.2012.21019
Abstract: This paper concerns the influence of temperature and local concentration of oxygen on the conversion efficiency of carbon into CO, CO2, CH4, C3H8, C2H4, C2H2, C2H6, C6H6, during the thermal degradation of plastic bags and millet stalks. The experimental device used is the tubular kiln, coupled to an analyzer Fourier Transform Infrared (FTIR) and a Non Dispersive Infrared analyzer (NDIR). Temperatures are considered between 800 and 1000°C. Local concentrations of oxygen during thermal degradation are 0%, 10% and 21%. On the one hand results obtained on the influence of temperature show that for each type of thermal degradation and whatever the temperature of the combustion, the rate of conversion of carbon remains substantially the same. In the case of plastic bags, the rate of carbon converted during pyrolysis is about 90% of carbon converted during reductive combustion. On the other hand, with millet stalks, the carbon converted represents only 60% of the rate of carbon converted during combustion to 10% oxygen. 1 to 2% of carbon not analyzed is in the form of aromatic compounds that are found most often in the soot and/or tar from this combustion system. Moreover, whatever the temperature, the overall efficiency of carbon conversion increases linearly with the local concentration of oxygen. During the thermal degradation of plastic bags, we see that the reducer environment has fostered the conversion of 7% of carbon more while the presence of oxygen in double proportion promotes the conversion of 27% carbon. Regarding the influence of the local content of oxygen, it is clear that for plastic bags, the reactions of oxidation of CO into CO2 tend to be favored for the benefit of those of hydrocarbons into CO. The formation of CO and CO2 by oxidation of light hydrocarbons is primarily from gaseous compounds CH4 and C2H4. At 950°C, we have also acetylene (C2H2) which is involved in the production of carbon oxides. At 1000°C, benzene (C6H6) heavily involved in the formation of CO and CO2. However, with millet stalks, more the local content of oxygen increases, more combustion is better, that is to say that the oxidation reactions producing CO2 are faster than the oxidation reactions of hydrocarbons into CO. The rate of carbon converted into CO and CO2 is higher for millet stalks than for plastic
Contribution to the Design of a Pottery Kiln Using as Fuel a Mixture of Cellulosic and Plastic Materials: Influence of the Proportion of Plastic on the Emissions of NO, CO2, O2  [PDF]
Salifou K. Ouiminga, Thomas Rogaume, Alfa Oumar Dissa, Samuel Ouoba, Tizane Daho, Jean Koulidiati
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2012, DOI: 10.4236/jasmi.2012.23028
Abstract: This paper concerns the study of the influence of the proportion of plastic from polyethylene, on the yields of gas emissions during the combustion of the mixture of “millet stalks and polyethylene plastic bags”, in a prototype of kiln of potters. During these investigations, we looked at the rate of residual oxygen (O2) and emissions of carbon dioxide (CO2) and nitrogen monoxide (NO), as a function of primary air flow (Q1) and secondary airflow (Q2). The potter’s kilns are considered those fueled by natural air flow. The primary air flows ranging from 45 to 85 Nm3?h 1 and secondary air flows from 20 to 60 Nm3?h 1. To conduct this numerical study, the model used is “reactor” based on the code CHEMKIN II. The modeled area is composed into a multitude of perfectly stirred reactors (PSR) and the kinetic model has 893 species and 113 reversible chemical reactions. The results show that in our test conditions, the increasing of the rate of plastic in the mixture produces a decrease of the residual oxygen content, due to higher oxygen consumption regardless of the airflow. The CO2 emissions are an increasing function of the rate of plastic (polyethylene) in the fuel mixture. Finally, NO emissions are increasing functions of the mass of plastic for a proportions less than or equal to 20%, and are essentially controlled by the temperature of the reactional medium.
Simulation and Evaluation of Dust Emission with Polair3D-SIREAM Model over West Africa Focused on Ouagadougou (Burkina Faso)  [PDF]
Bernard Nana, Oumar Sanogo, Issoufou Ouarma, Antoine Béré, Jean Koulidiati
Journal of Environmental Protection (JEP) , 2019, DOI: 10.4236/jep.2019.101006
Abstract: The study of air pollution is recent in West Africa. There is a lack of data on air pollution. However, some studies conducted in West Africa show that air quality is a concern. Population growth and massive vehicles imports are contributing to the deterioration of this air quality. In this work, we present the modelling of desert aerosols using a CTM Polair3D-SIREAM. The objective is to evaluate the ability of Polair3D-SIREAM to reproduce observations of PM10 and Aerosol Optical Thicknesses (AOT). A simulation with Polair3D-SIREAM was carried out in West Africa, focused on Ouagadougou (Burkina Faso) for 2007. The model of Marticorena and Bergametti (1995), MB95, was used to estimate desert aerosols emissions. The total emission of dust modelled is 52.2 Tg. For the evaluation of PM10, the simulated averages remained within the same orders of magnitude as the observed averages. Correlations are low in all the observation sites. The other indicators are similar to those found by Schmechtig et al. (2011). Performance criteria of Boylan and Russel (2006) are met for the observation sites of Ouagadougou and Ilorin (Nigeria). For the AOTs, the correlations are significantly improved, in particular, at the sites of Ouagadougou and Ilorin. Performance criteria of Boylan are met for all observation sites. However, the performance goals are only achieved for Ouagadougou and Ilorin.
Contribution to the Modeling of a Solar Adsorption Refrigerator under the Climatic Conditions of Burkina Faso  [PDF]
Guy Christian Tubreoumya, Alfa Oumar Dissa, Eloi Salmwendé Tiendrebeogo, Xavier Chesneau, Aboubacar Compaoré, Kayaba Haro, Charles Didace Konseibo, Belkacem Zeghmati, Jean Koulidiati
Energy and Power Engineering (EPE) , 2017, DOI: 10.4236/epe.2017.92010
Abstract: This work concerns a dynamic modeling and a numerical simulation of the operation of an adsorption solar refrigeration system using the zeolite-water couple. For this, a mathematical model representing the evolution of heat and mass transfer at each component of the solar adsorption refrigerator has been developed. We have adopted the Dubinin-Astakhov model for the adsorption kinetics of the zeolite/water pair. This model allows to describe the phenomenon of adsorption and to calculate the rate of adsorbate (water) in the zeolite (adsorbent) as a function of the temperature and the pressure. The equations governing the operation of the solar adsorption refrigerator, deduced from the thermal and mass balances established at the collector adsorber, condenser and evaporator components, were solved by an implicit finite difference scheme and Gauss Seidel’s iterative method. We have validated the model established by applying it to the model of Allouhi et al. 2014. We analyzed the influence of the adsorbate/adsorbent couples, the solar flux, the ambient temperature on the adsorption and desorption process. The temperature profiles obtained representing the temperature evolution of the glass, the absorbent plate, the zeolite-water mixture, the condenser, the evaporator, as well as the pressure and the adsorbed mass allowed us to evaluate the performance of the solar adsorption refrigerator. SCOP is higher the higher the solar flux captured by the collector-adsorber.
Hydric Properties Evolution of Spirulina platensis during Drying: Experimental Analysis and Modeling  [PDF]
Eloi Salmwendé Tiendrebeogo, Guy Christian Tubreoumya, A. O. Dissa, A. Compaoré, Jean Koulidiati, F. Cherblanc, J.-C. Bénet, I. Youm
Food and Nutrition Sciences (FNS) , 2019, DOI: 10.4236/fns.2019.106041
Abstract: Hydric properties evolution during drying differs from one product to another and has been the subject of various studies due to its crucial importance in modeling the drying process. The variation of these parameters in the solid matrix and in time during the drying of Spirulina platensis has not known an advanced understanding. The objective of this study was to evaluate the evolution of the water content profile, the mass flow, the concentration gradient and the diffusion coefficient during the drying of Spirulina platensis taking into account the shrinkage. Modeling and experimental analysis (at 50°C and HR = 6%) by the cutting method a cylinder 20 mm in diameter and 40 mm thick were carried. The water content profiles of two different products grown in semi-industrial farms from Burkina Faso and France with initial water contents respectively of the range from 2.73 kgw/kgdb and 3.12 kgw/kgdb were determined. These profiles have been adjusted by a polynomial function. Identical water behavior is observed regardless of the origin of the samples. Water distribution is heterogeneous. Mass flow and concentration gradient are greater at the edge than inside the product. The water transport coefficient, ranging from 1.70 × 10?10 to 94 × 10?10 m2/s, is determined from a linear approach.
The Effect of Atmospheric Oxygen on the Puffing and Bursting Phenomena during Vegetable Oils Droplets Vaporization Process for Their Use as Biofuel in Diesel Engine  [PDF]
A. S. Zongo, T. Daho, G. Vaitilingom, B. Piriou, J. Valette, C. Caillol, B. G. Segda, P. Higelin, J. Koulidiati
Energy and Power Engineering (EPE) , 2018, DOI: 10.4236/epe.2018.1012033
Abstract: The past literature on the use of vegetable oils as fuel in diesel engine revealed that utilizing vegetable oil fuels in diesel engines may require property changes in the oil or perhaps, some minor engine modifications or operating changes. This study was conducted to search for the effect of atmospheric oxygen on the puffing and bursting phenomena that occur during vegetable oils droplet vaporization process in their use as fuel in diesel engine. The fiber-suspended droplet technique was used, and the normalized square droplet diameter as well as the temperature evolution vicinity the droplet was analyzed. The results show that puffing and bursting phenomena highly depend on oxygen. In presence of atmospheric oxygen, there is an increase of the puffing and bursting intensity and therefore the evaporation rate of the vegetable oil droplets, but in an inert environment or when the environment is oxygen-depleted puffing and bursting phenomena disappearing and make place of a series of explosions with lower magnitude. The lack of oxygen reduces the thermal degradation, polymerization and oxidation reactions and consequently the vaporization rate of vegetable oils droplets; and could therefore lead to the formation of deposits in the form of polymers. This is unsuitable for their use as a fuel in diesel engines. It can also be concluded that atmospheric oxygen has some positive effects on engine performance and emissions when operating with vegetable oil. These results help to address the challenge for the use of alternative fuels such as non-edible vegetable oils.
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