Poor wastewater management coupled with lack of sanitation facilities has aggravated the sanitation challenges in developing countries.?This study was aimed at providing information on the current state of sanitation ...Poor wastewater management coupled with lack of sanitation facilities has aggravated the sanitation challenges in developing countries.?This study was aimed at providing information on the current state of sanitation in Cotonou City through surveys. The most common sanitation facilities in the city were septic tanks, latrines and soakaway pits. Mechanical desulging was mainly used (94%) for desludging latrines and septic tanks with a frequency of less than once a year for 73% of the houses;manual desludging was most common for soakaway pits. 84% of sullage generated is disposed without treatment. The only existing stabilization pond plant, managed by a private company SIBEAU, is overloaded;the effluent is poor (up to 2250mg/l BOD5) and does not meet any quality standards. 96% of survey respondents recognise that the sanitation situation in the city is not good;it has to be improved by providing an appropriate and sustainable sanitation management system.展开更多
The Rehabilitated Mudor sewage treatment plant at James Town was monitored over a period of 4 months (October 2017 to January 2018). This study analyzed the physical, chemical and biological parameters of the raw sewa...The Rehabilitated Mudor sewage treatment plant at James Town was monitored over a period of 4 months (October 2017 to January 2018). This study analyzed the physical, chemical and biological parameters of the raw sewage and the treated effluent from the plant. The result indicates that the total removal efficiencies were 98.8%, 91.2%, 62.8%, 28.6%, 81.7%, 43.6%, 82.5% and 99.6% for BOD, COD, TSS, Nitrate-Nitrogen, Phosphate-Phosphorus, Ammonia-nitrogen, Sulphate and faecal coliform respectively. More than 13 parameters needed to be met according to the Ghana Environmental Protection Agency (EPA) guideline were satisfactorily met whiles ammonia, total suspended solids and phosphate were slightly out of range. From the results obtained, the overall performance of the rehabilitated plant was satisfactory and has seen some improvement with respect to the former recorded performance of the plant. With monitoring operation parameters for waste water plants discharge guidelines becoming stringent over the past years, it could be said that management of the Mudor rehabilitated treatment plant is on the right cause with full scale operation of the plant barely less than a year. Increase in the process steps through rehabilitation resulted in several significant improvements in effluent quality parameters.展开更多
In this study, downwind odour concentrations from a communal toilet facility were measured by trained human receptors using the plume method over a 10 day period from mid-May to mid-June 2015 over an approximate downw...In this study, downwind odour concentrations from a communal toilet facility were measured by trained human receptors using the plume method over a 10 day period from mid-May to mid-June 2015 over an approximate downwind area of 1000 m<sup>2</sup> (about 800 m long and 30 m). Source emission measurements and extensive meteorological data were collected along with the field odor concentration measurements. Modelling of the measurement events at specific receptor locations using the US EPA SCREEN3 model was compared to field odor measurements at the same locations. The study also showed how subjectivity in the use of the human nose in measuring odour strength could be reduced by selecting odour inspectors using the “Standard Procedure for Testing Individual Odour Sensitivity”. Also an odour dispersion model using the US EPA SCREEN3 model was built and simulated and the output of the simulated model compared with the measured data. A paired t-test, t(5) = -1.29, p = 0.902 (p > 0.05), showed that there was no statistically significant difference between simulated model output and measured data, hence the possible of using odour dispersion models improved operation of a communal toilet in relation to odour impact.展开更多
文摘Poor wastewater management coupled with lack of sanitation facilities has aggravated the sanitation challenges in developing countries.?This study was aimed at providing information on the current state of sanitation in Cotonou City through surveys. The most common sanitation facilities in the city were septic tanks, latrines and soakaway pits. Mechanical desulging was mainly used (94%) for desludging latrines and septic tanks with a frequency of less than once a year for 73% of the houses;manual desludging was most common for soakaway pits. 84% of sullage generated is disposed without treatment. The only existing stabilization pond plant, managed by a private company SIBEAU, is overloaded;the effluent is poor (up to 2250mg/l BOD5) and does not meet any quality standards. 96% of survey respondents recognise that the sanitation situation in the city is not good;it has to be improved by providing an appropriate and sustainable sanitation management system.
文摘The Rehabilitated Mudor sewage treatment plant at James Town was monitored over a period of 4 months (October 2017 to January 2018). This study analyzed the physical, chemical and biological parameters of the raw sewage and the treated effluent from the plant. The result indicates that the total removal efficiencies were 98.8%, 91.2%, 62.8%, 28.6%, 81.7%, 43.6%, 82.5% and 99.6% for BOD, COD, TSS, Nitrate-Nitrogen, Phosphate-Phosphorus, Ammonia-nitrogen, Sulphate and faecal coliform respectively. More than 13 parameters needed to be met according to the Ghana Environmental Protection Agency (EPA) guideline were satisfactorily met whiles ammonia, total suspended solids and phosphate were slightly out of range. From the results obtained, the overall performance of the rehabilitated plant was satisfactory and has seen some improvement with respect to the former recorded performance of the plant. With monitoring operation parameters for waste water plants discharge guidelines becoming stringent over the past years, it could be said that management of the Mudor rehabilitated treatment plant is on the right cause with full scale operation of the plant barely less than a year. Increase in the process steps through rehabilitation resulted in several significant improvements in effluent quality parameters.
文摘In this study, downwind odour concentrations from a communal toilet facility were measured by trained human receptors using the plume method over a 10 day period from mid-May to mid-June 2015 over an approximate downwind area of 1000 m<sup>2</sup> (about 800 m long and 30 m). Source emission measurements and extensive meteorological data were collected along with the field odor concentration measurements. Modelling of the measurement events at specific receptor locations using the US EPA SCREEN3 model was compared to field odor measurements at the same locations. The study also showed how subjectivity in the use of the human nose in measuring odour strength could be reduced by selecting odour inspectors using the “Standard Procedure for Testing Individual Odour Sensitivity”. Also an odour dispersion model using the US EPA SCREEN3 model was built and simulated and the output of the simulated model compared with the measured data. A paired t-test, t(5) = -1.29, p = 0.902 (p > 0.05), showed that there was no statistically significant difference between simulated model output and measured data, hence the possible of using odour dispersion models improved operation of a communal toilet in relation to odour impact.
