This study was carried out at the Mamou Higher Institute of Technology during the period from March 10 to April 15, 2022, with the aim of designing and testing a solar dryer with forced convection by drying potatoes. ...This study was carried out at the Mamou Higher Institute of Technology during the period from March 10 to April 15, 2022, with the aim of designing and testing a solar dryer with forced convection by drying potatoes. The dryer was designed using local materials. Its main geometric parameters are: 1) height of the drying chamber (90 cm), 2) length of the drying chamber (50 cm), 3) width of the drying chamber (43 cm), 4) surface of the racks (0.1806 m<sup>2</sup>), 5) surface of the heat accumulator (0.2537 m<sup>2</sup>). The experiment focused on the vacuum test of the dryer for two days and that of the drying of the sweet potato for three days from 8:30 a.m. to 5:30 p.m. The average vacuum test temperature values of the three environments are respectively accumulator (43°C), dryer chamber (41°C) and ambient environment (34°C). Four kilograms (4 kg) of boiled sweet potato were dried. The average temperatures in the accumulator and in the drying chamber during the three days of drying are respectively 33°C and 39°C. The final mass of the dried product is 1.2 kg, with a quantity of water extracted of 2 liters or 63% of the initial mass of the product. The average drying rate is 0.074 kg/h. The drying kinetics showed a decreasing rate in the absence of the heating period and the constant rate period.展开更多
In the town of Mamou,all homes with sanitation systems are equipped with autonomous installations not connected to a sewer network.The emptying service is provided by manual emptiers and by the living environment and ...In the town of Mamou,all homes with sanitation systems are equipped with autonomous installations not connected to a sewer network.The emptying service is provided by manual emptiers and by the living environment and sanitation service of the urban municipality which has a single 6 m^(3)truck.The objective of this work is to determine the quantity of fecal sludge produced within the city for sustainable management.The methodology adopted is based on a field survey and the use of three methods for evaluating the quantities of sludge(specific production,quantity of sludge collected by the sludge truck and the total production of sludge produced in the various sludge works).The results obtained show that,out of the 2,940 sanitation works identified,2,936 works have been emptied at least once since their construction.Then 2,307 structures are emptied manually or 78.57%,against;619 structures emptied mechanically or 21.08%.The structures are emptied on average every 3 years for septic tanks and every 5 years for dry latrines.The specific production of sludge is 685,241,532 m^(3)/year;the production of sludge by the mechanical emptying technique varies from 588,641.57 m^(3)/year to 724,800.46 m^(3)/year and the production of sludge by manual emptying is 1,573,709.33 m^(3)/year,for a total quantity of sludge produced including between 2,162,350 m^(3)/year to 685,241,531.9 m^(3)/year.展开更多
文摘This study was carried out at the Mamou Higher Institute of Technology during the period from March 10 to April 15, 2022, with the aim of designing and testing a solar dryer with forced convection by drying potatoes. The dryer was designed using local materials. Its main geometric parameters are: 1) height of the drying chamber (90 cm), 2) length of the drying chamber (50 cm), 3) width of the drying chamber (43 cm), 4) surface of the racks (0.1806 m<sup>2</sup>), 5) surface of the heat accumulator (0.2537 m<sup>2</sup>). The experiment focused on the vacuum test of the dryer for two days and that of the drying of the sweet potato for three days from 8:30 a.m. to 5:30 p.m. The average vacuum test temperature values of the three environments are respectively accumulator (43°C), dryer chamber (41°C) and ambient environment (34°C). Four kilograms (4 kg) of boiled sweet potato were dried. The average temperatures in the accumulator and in the drying chamber during the three days of drying are respectively 33°C and 39°C. The final mass of the dried product is 1.2 kg, with a quantity of water extracted of 2 liters or 63% of the initial mass of the product. The average drying rate is 0.074 kg/h. The drying kinetics showed a decreasing rate in the absence of the heating period and the constant rate period.
文摘In the town of Mamou,all homes with sanitation systems are equipped with autonomous installations not connected to a sewer network.The emptying service is provided by manual emptiers and by the living environment and sanitation service of the urban municipality which has a single 6 m^(3)truck.The objective of this work is to determine the quantity of fecal sludge produced within the city for sustainable management.The methodology adopted is based on a field survey and the use of three methods for evaluating the quantities of sludge(specific production,quantity of sludge collected by the sludge truck and the total production of sludge produced in the various sludge works).The results obtained show that,out of the 2,940 sanitation works identified,2,936 works have been emptied at least once since their construction.Then 2,307 structures are emptied manually or 78.57%,against;619 structures emptied mechanically or 21.08%.The structures are emptied on average every 3 years for septic tanks and every 5 years for dry latrines.The specific production of sludge is 685,241,532 m^(3)/year;the production of sludge by the mechanical emptying technique varies from 588,641.57 m^(3)/year to 724,800.46 m^(3)/year and the production of sludge by manual emptying is 1,573,709.33 m^(3)/year,for a total quantity of sludge produced including between 2,162,350 m^(3)/year to 685,241,531.9 m^(3)/year.
