130 research outputs found
Assessment of wash program in public secondary schools in south-western Nigeria
The provision of safe water, sanitation and hygiene in schools has been established to improve health, boost
educational achievement, and promote gender equity which has a positive impact on the society. The aim of this pilot study
is to ascertain the state of WASH program in public secondary schools in South-Western Nigeria. A total of twelve schools
which span across three Local Government areas in two States (Lagos and Ogun), in South-Western Nigeria were selected.
The standard for WASH in schools by UNICEF was used as the guiding principles to evaluate the adequacy of the various
WASH components. Out of the 12 public secondary schools visited, only 3 (25%) had drinking water points (boreholes)
and 40% of the schools do not have separate latrines for boys and girls, and for promoting privacy of older girls. Only 1
(10%) of the schools had hand washing points but without soap and there is no plan in the schools for advancing WASH
program. This study reveals that the present WASH practice in many of the schools is not adequate
Evaluation of the Influence of Reactor Design on the Treatment Performance of an Optimized Pilot-Scale Waste Stabilization Pond
Waste stabilization pond (WSP) is globally one of the most popular wastewater treatment options due to its high efficiency and low cost. A field scale prototype was designed and scaled down to a pilot-scale model using dimensional analysis in the development of the foot print size. Pilot-scale reactors were built with the specifications produced from literature suggested reactor geometric configurations and experimental study was conducted to evaluate the performance of optimized pilot-scale WSP configurations. The optimized pilot scale WSPs consisted of an anaerobic, facultative, and a maturation stage with varying baffle orientation, length to width ratio, and depth. Comparisons were made on the optimized pilot-scale WSP reactors. The removal performance of the experimental test was based on a number of parameters (Faecal coliform, pH, TDS, and Conductivity). Results showed that the significantly lower cost design displayed slightly better removal performance compared to other WSP design developed from literature data. This paper covers a relevant subject within the field of waste stabilization ponds, namely the representation of the influence of reactor design on the treatment performance of WSP
Environment, Health and Wealth: Towards an Analysis of Municipal Solid Waste Management in Ota, Ogun State, Nigeria
The management of municipal solid waste is one of the challenges facing the developing countries because
governments, institutions, and private sectors have given solid waste management low priority and ignoring
the implication it has on the general public. This is characterized by inefficient collection methods,
insufficient coverage of the collection system and improper disposal. This paper presents the current solid
waste management method adopted in Ado-Odo Ota local government and its associated challenges. Four
locations (Iganmode area, Joju area, Ota market and toll gate area) were selected. These sites are points
where the waste bins are located. A field work that involves the characterization and types of the waste
generated, and frequency of collection from each site was carried out. A representative sample of 280 kg
was used for the waste characterization and the result shows that about 64% of the wastes are recyclable
with lots of organic waste that comprises of food and agricultural waste which can be used as compost. The
only dump site in Ota was visited in order to obtain useful information concerning the present state of solid
waste management. The study revealed that there is presently no investment made to the existing
development plan to introduce a modern waste management system. The study suggests new approach
that could be used by institutions and government agencies for municipal solid waste management to
achieve sustainable and effective sanitation
Heavy Metal Concentrations in Road Side Soils from Selected Locations in the Lagos Metropolis, Nigeria
Assessing the concentration of potentially harmful heavy metals in road side soils in Lagos metropolis is imperative in order to evaluate the potential risks to people and the environment. This is due to rapid increase in the use of vehicles for day to day transportation coupled with lack of emission standards which has raised serious concern about vehicular pollution. This paper reports the results of the investigation of heavy metal concentration in road side soils of selected areas in Lagos metropolis as a result of vehicular pollution. Locations considered were motor parks, garages and roadsides in Alimosho-, Agege-, Ikeja-, and Oshodi/Isolo-LGA of Lagos State. Seven locations that spans across the four local governments were selected on the basis of their high concentration of vehicular traffic. Three sites with low traffic concentration were also selected outside the seven locations to act as control sites. Soil samples were collected at each location for a period of three months in the dry season. The concentrations of six heavy metals (manganese, nickel, lead, chromium, zinc, and iron) in the samples were determined with an atomic absorption spectrometer (AAS). All the monitored heavy metal pollutants where compared with European Union (EU) regulatory standard. Results show that the concentrations of heavy metals in the soil samples from the seven locations were within safe limits though higher than in the control sites. It is evident that as time goes on, these heavy metals may pose health hazards. The study reveals that vehicular-related pollution in Lagos metropolis is indeed significant with possible severe health consequences
Rainfall-Runoff Relationships and flow forecasting, Ogun river Nigeria
An excess or a lack of rainfall are the major causes of most hydrological hazards, and the need
for a systematic approach to river flow forecasting based on rainfall is imperative, especially
in Nigeria. A study was carried out on three major gauging stations of the Ogun river basin
to determine the rainfall-discharge relationship and model equations for use in the basin and
similar basins. Stream flow and rainfall data for at least seven consecutive years for each
station were collected and analyzed. The rainfall-runoff data were subjected to linear,
exponential and higher order analysis. Stream flow data were also fitted to normal, log-normal
and log-Pearson Type III distributions. The selection of the appropriate probability distribution
model for each gauging station was based on graphical comparisons between observed
and predicted flows and goodness-of-fit tests using chi-square and probability correlation
coefficients. Results show that model equations with logarithmic and exponential relationships
between rainfall and discharge gave better and more realistic prediction estimates and can be
used for the basin. It was determined that the peak discharges occurred when the rainfall
values were at their maximum, and a distinct relationship between the discharge and rainfall
exists at each of the gauging stations
Hydraulic Modelling and Optimization of a Wastewater Treatment System for Developing Nations Using Computational Fluid Dynamics
Waste stabilization pond (WSP) is globally one of the most popular wastewater treatment options because
of its high efficiency and low cost. However, no rigorous assessment of WSPs that account for cost in
addition to hydrodynamics and treatment efficiency has been performed. A study was conducted that
utilized Computational Fluid Dynamics (CFD) coupled with an optimization program to optimize the
selection of the best WSP configuration based on cost and treatment efficiency. Several designs generated
by the CFD/optimization model showed that both shorter and longer baffles, alternative depths, and reactor
length to width ratios could improve the hydraulic efficiency of the ponds at a reduced overall construction
cost. In addition, a study was conducted on the optimized WSP which consisted of an anaerobic,
facultative, and a maturation stage whose baffle orientation, length to width ratio, was specified by a CFD
model prediction and was compared with a three stage WSP designed according to literature suggested
reactor geometric configurations. Experimental tests were performed on a pilot scale version of the threestage
WSP where the removal performance was based on a number of parameters (Faecal coliform, pH,
TDS, and Conductivity). Results showed that the significantly lower cost design based on the optimized
CFD simulations displayed slightly better removal performance compared to the standard WSP design
developed from literature data. The results of this study clearly showed that unit treatment process designs
based on rigorous numerical optimization can aid in producing cost effective designs that make it more
possible for developing nations to incorporate adequate and effective sanitation
Assessment of Vehicular Pollution of Road Side Soils in Ota Metropolis, Ogun State, Nigeria
Vehicular emission has been found to constitute one
of the major sources of soil pollution. We have investigated the
influence of vehicular emissions on the accumulation of heavy
metal in the roadside soils of Ota metropolis, Ogun State,
Nigeria. The main objective of this research was to determine the
impact of heavy metals such as copper, cadmium, lead,
manganese, nickel and sulphate from vehicular pollution on soil
around Ota. Seven locations were selected on the basis of their
high concentration of vehicular traffic. Three sites with low
traffic concentration were also selected outside the seven
locations to act as control sites. Samples were taken in a period of
three months in the dry season. The concentrations of five heavy
metals and sulphate in the samples were determined with an
atomic absorption spectrometer. The concentrations of the heavy
metals from the seven main sites were higher than in the control
sites. The concentration of each heavy metal and sulphate in the
seven locations was below the European Union regulatory
standard. Although these concentration are below the European
Union regulatory standard, these heavy metals and sulphate,
which over time are washed by erosion into the local areas used
for farming, may pose health hazards. The enhancement of fuel
quality and the adoption of emission standards to mitigate the
impact of vehicular emissions on human health should be made
mandatory
HYDRAULIC MODELING AND OPTIMIZATION OF WASTE STABILIZATION POND DESIGN FOR DEVELOPING NATIONS
Wastewater stabilization ponds (WSPs) have been identified and are used extensively to
provide wastewater treatment throughout the world. It is often preferred to the
conventional treatment systems due to its higher performance in terms of pathogen
removal, its low maintenance and operational cost. A review of the literature revealed that
there has been limited understanding on the fact that the hydraulics of waste stabilization
ponds is critical to their optimization. The research in this area has been relatively limited
and there is an inadequate understanding of the flow behavior that exists within these
systems. This work therefore focuses on the hydraulic study of a laboratory-scale model
WSP, operated under a controlled environment using computational fluid dynamics (CFD)
modelling and an identified optimization tools for WSP.
A field scale prototype pond was designed for wastewater treatment using a typical
residential institution as a case study. This was reduced to a laboratory-scale model using
dimensional analysis. The laboratory-scale model was constructed and experiments were
run on them using the wastewater taken from the university wastewater treatment facility.
The study utilized Computational Fluid Dynamics (CFD) coupled with an optimization
program to efficiently optimize the selection of the best WSP configuration that satisfy
specific minimum cost objective without jeopardizing the treatment efficiency. This was
done to assess realistically the hydraulic performance and treatment efficiency of scaled
WSP under the effect of varying ponds configuration, number of baffles and length to
width ratio. Six different configurations including the optimized designs were tested in the
laboratory to determine the effect of baffles and pond configurations on the effluent
characteristics. The verification of the CFD model was based on faecal coliform
inactivation and other pollutant removal that was obtained from the experimental data.
The results of faecal coliform concentration at the outlets showed that the conventional
70% pond-width baffles is not always the best pond configuration as previously reported
in the literature. Several other designs generated by the optimization tool shows that both
shorter and longer baffles ranging between 49% and 83% for both single and multiobjective
optimizations could improve the hydraulic efficiency of the ponds with different
variation in depths and pond sizes. The inclusion of odd and even longitudinal baffle
arrangement which has not been previously reported shows that this configuration could
improve the hydraulic performance of WSP. A sensitivity analysis was performed on the
model parameters to determine the influence of first order constant (k) and temperature
(T) on the design configurations. The results obtained from the optimization algorithm
considering all the parameters showed that changing the two parameters had effect on the
effluent faecal coliform and the entire pond configurations.
This work has verified its use to the extent that it can be realistically applied for the
efficient assessment of alternative baffle, inlet and outlet configurations, thereby,
addressing a major knowledge gap in waste stabilization pond design. The significance of
CFD model results is that water and wastewater design engineers and regulators can use
CFD to reasonably assess the hydraulic performance in order to reduce significantly faecal
coliform concentrations and other wastewater pollutants to achieve the required level of
pathogen reduction for either restricted or unrestricted crop irrigation
Integrating Water, Sanitation and Hygiene (WaSH) Program into Educational Institutions Policy in Nigeria.
The provision of safe water, sanitation and hygiene (WASH) in educational institutions has been established to improve health, boost educational achievement, and promote gender equity which has a positive impact on the society. However, most public secondary schools in Nigeria are short of the basic water and sanitation facilities, and hygiene education programs are often inadequate. The aim of this study is to ascertain the state of WASH program in the educational institutions. This was assessed by investigating the causes of inadequate potable water supply, poor sanitation and deficient hygiene education in public secondary schools. A total of fifteen schools were selected for the study which span across three Cities (Lagos, Abeokuta and Ota) in two States (Lagos and Ogun), in South-Western Nigeria. The standard for WASH in schools by UNICEF was used as the guiding principles to evaluate the adequacy of the various WASH components. Out of the 12 public secondary schools visited, only 3 (25%) had drinking water points (boreholes) and 40% of the schools do not have separate latrines for boys and girls. Only 1 (10%) of the schools had hand washing points but without soap. One school reported giving hygiene talk once in a term whereas there are no facilities and program in the schools for promoting safety, privacy and security of older girls. In all the schools, open dump system of solid waste disposal that are not properly managed is the general practice. This study reveals that the present WASH facilities and practices in many of the schools are not satisfactory. Therefore, to maximize the potential of students as the most persuasive advocates of good WASH practices in the society, it is necessary to integrate WASH program into national education policy and schools should be provided with adequate facilities.
Assessment of Impact of Hydropower Dams Reservoir Outflow on the Downstream River Flood Regime – Nigeria’s Experience
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